feat: add tests and assert coverage (#71)

### Explanation

_No response_

### Issue

_No response_

### Attestations

- [ ] I have read and agree to the [Code of Conduct](https://docs.nhcarrigan.com/community/coc/)
- [ ] I have read and agree to the [Community Guidelines](https://docs.nhcarrigan.com/community/guide/).
- [ ] My contribution complies with the [Contributor Covenant](https://docs.nhcarrigan.com/dev/covenant/).

### Dependencies

- [ ] I have pinned the dependencies to a specific patch version.

### Style

- [ ] I have run the linter and resolved any errors.
- [ ] My pull request uses an appropriate title, matching the conventional commit standards.
- [ ] My scope of feat/fix/chore/etc. correctly matches the nature of changes in my pull request.

### Tests

- [ ] My contribution adds new code, and I have added tests to cover it.
- [ ] My contribution modifies existing code, and I have updated the tests to reflect these changes.
- [ ] All new and existing tests pass locally with my changes.
- [ ] Code coverage remains at or above the configured threshold.

### Documentation

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### Versioning

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Co-authored-by: Hikari <hikari@nhcarrigan.com>
Reviewed-on: #71
Co-authored-by: Naomi Carrigan <commits@nhcarrigan.com>
Co-committed-by: Naomi Carrigan <commits@nhcarrigan.com>

src-tauri/src/clipboard.rs

@@ -257,3 +257,468 @@ pub fn update_clipboard_language(
     save_history(&app, &history)?;
     Ok(updated_entry)
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    // ==================== ClipboardEntry tests ====================
+
+    #[test]
+    fn test_clipboard_entry_new() {
+        let entry = ClipboardEntry::new(
+            "let x = 42;".to_string(),
+            Some("rust".to_string()),
+            Some("main.rs".to_string()),
+        );
+
+        assert_eq!(entry.content, "let x = 42;");
+        assert_eq!(entry.language, Some("rust".to_string()));
+        assert_eq!(entry.source, Some("main.rs".to_string()));
+        assert!(!entry.is_pinned);
+        assert!(!entry.id.is_empty());
+        assert!(!entry.timestamp.is_empty());
+    }
+
+    #[test]
+    fn test_clipboard_entry_new_without_optional_fields() {
+        let entry = ClipboardEntry::new("some content".to_string(), None, None);
+
+        assert_eq!(entry.content, "some content");
+        assert!(entry.language.is_none());
+        assert!(entry.source.is_none());
+        assert!(!entry.is_pinned);
+    }
+
+    #[test]
+    fn test_clipboard_entry_unique_ids() {
+        let entry1 = ClipboardEntry::new("content1".to_string(), None, None);
+        let entry2 = ClipboardEntry::new("content2".to_string(), None, None);
+
+        assert_ne!(entry1.id, entry2.id);
+    }
+
+    #[test]
+    fn test_clipboard_entry_serialization() {
+        let entry = ClipboardEntry::new(
+            "fn main() {}".to_string(),
+            Some("rust".to_string()),
+            Some("lib.rs".to_string()),
+        );
+
+        let json = serde_json::to_string(&entry).unwrap();
+        assert!(json.contains("fn main() {}"));
+        assert!(json.contains("rust"));
+        assert!(json.contains("lib.rs"));
+        assert!(json.contains("is_pinned"));
+
+        let deserialized: ClipboardEntry = serde_json::from_str(&json).unwrap();
+        assert_eq!(deserialized.content, entry.content);
+        assert_eq!(deserialized.language, entry.language);
+        assert_eq!(deserialized.source, entry.source);
+        assert_eq!(deserialized.id, entry.id);
+    }
+
+    #[test]
+    fn test_clipboard_entry_clone() {
+        let entry = ClipboardEntry::new(
+            "original".to_string(),
+            Some("python".to_string()),
+            None,
+        );
+
+        let cloned = entry.clone();
+        assert_eq!(cloned.content, entry.content);
+        assert_eq!(cloned.id, entry.id);
+        assert_eq!(cloned.language, entry.language);
+    }
+
+    #[test]
+    fn test_clipboard_entry_timestamp_is_rfc3339() {
+        let entry = ClipboardEntry::new("test".to_string(), None, None);
+
+        // RFC3339 timestamp should parse successfully
+        let parsed = chrono::DateTime::parse_from_rfc3339(&entry.timestamp);
+        assert!(parsed.is_ok());
+    }
+
+    // ==================== ClipboardHistory tests ====================
+
+    #[test]
+    fn test_clipboard_history_default() {
+        let history = ClipboardHistory::default();
+        assert!(history.entries.is_empty());
+    }
+
+    #[test]
+    fn test_clipboard_history_serialization() {
+        let mut history = ClipboardHistory::default();
+        history.entries.push(ClipboardEntry::new(
+            "entry1".to_string(),
+            Some("js".to_string()),
+            None,
+        ));
+        history.entries.push(ClipboardEntry::new(
+            "entry2".to_string(),
+            None,
+            Some("file.txt".to_string()),
+        ));
+
+        let json = serde_json::to_string(&history).unwrap();
+        assert!(json.contains("entry1"));
+        assert!(json.contains("entry2"));
+        assert!(json.contains("js"));
+        assert!(json.contains("file.txt"));
+
+        let deserialized: ClipboardHistory = serde_json::from_str(&json).unwrap();
+        assert_eq!(deserialized.entries.len(), 2);
+    }
+
+    #[test]
+    fn test_clipboard_history_entries_order() {
+        let mut history = ClipboardHistory::default();
+
+        history.entries.push(ClipboardEntry::new("first".to_string(), None, None));
+        history.entries.push(ClipboardEntry::new("second".to_string(), None, None));
+        history.entries.push(ClipboardEntry::new("third".to_string(), None, None));
+
+        assert_eq!(history.entries[0].content, "first");
+        assert_eq!(history.entries[1].content, "second");
+        assert_eq!(history.entries[2].content, "third");
+    }
+
+    // ==================== ClipboardState tests ====================
+
+    #[test]
+    fn test_clipboard_state_default() {
+        let state = ClipboardState::default();
+        assert!(state.last_content.is_none());
+    }
+
+    #[test]
+    fn test_clipboard_state_with_content() {
+        let state = ClipboardState {
+            last_content: Some("cached content".to_string()),
+        };
+        assert_eq!(state.last_content, Some("cached content".to_string()));
+    }
+
+    // ==================== MAX_HISTORY_SIZE constant test ====================
+
+    #[test]
+    fn test_max_history_size_is_reasonable() {
+        assert_eq!(MAX_HISTORY_SIZE, 100);
+        // Compile-time assertions for constant bounds
+        const _: () = assert!(MAX_HISTORY_SIZE > 0);
+        const _: () = assert!(MAX_HISTORY_SIZE <= 1000); // Sanity check
+    }
+
+    // ==================== Pinned entry sorting tests ====================
+
+    #[test]
+    #[allow(clippy::useless_vec)]
+    fn test_pinned_entries_sorting() {
+        let mut entries = vec![
+            ClipboardEntry {
+                id: "1".to_string(),
+                content: "unpinned older".to_string(),
+                language: None,
+                source: None,
+                timestamp: "2024-01-01T00:00:00Z".to_string(),
+                is_pinned: false,
+            },
+            ClipboardEntry {
+                id: "2".to_string(),
+                content: "pinned".to_string(),
+                language: None,
+                source: None,
+                timestamp: "2024-01-02T00:00:00Z".to_string(),
+                is_pinned: true,
+            },
+            ClipboardEntry {
+                id: "3".to_string(),
+                content: "unpinned newer".to_string(),
+                language: None,
+                source: None,
+                timestamp: "2024-01-03T00:00:00Z".to_string(),
+                is_pinned: false,
+            },
+        ];
+
+        // Apply the same sorting logic as used in the module
+        entries.sort_by(|a, b| {
+            if a.is_pinned && !b.is_pinned {
+                std::cmp::Ordering::Less
+            } else if !a.is_pinned && b.is_pinned {
+                std::cmp::Ordering::Greater
+            } else {
+                b.timestamp.cmp(&a.timestamp)
+            }
+        });
+
+        // Pinned should be first
+        assert!(entries[0].is_pinned);
+        assert_eq!(entries[0].id, "2");
+
+        // Then unpinned sorted by timestamp descending (newest first)
+        assert_eq!(entries[1].id, "3"); // newer unpinned
+        assert_eq!(entries[2].id, "1"); // older unpinned
+    }
+
+    #[test]
+    #[allow(clippy::useless_vec)]
+    fn test_multiple_pinned_entries_sorting() {
+        let mut entries = vec![
+            ClipboardEntry {
+                id: "1".to_string(),
+                content: "pinned older".to_string(),
+                language: None,
+                source: None,
+                timestamp: "2024-01-01T00:00:00Z".to_string(),
+                is_pinned: true,
+            },
+            ClipboardEntry {
+                id: "2".to_string(),
+                content: "unpinned".to_string(),
+                language: None,
+                source: None,
+                timestamp: "2024-01-02T00:00:00Z".to_string(),
+                is_pinned: false,
+            },
+            ClipboardEntry {
+                id: "3".to_string(),
+                content: "pinned newer".to_string(),
+                language: None,
+                source: None,
+                timestamp: "2024-01-03T00:00:00Z".to_string(),
+                is_pinned: true,
+            },
+        ];
+
+        entries.sort_by(|a, b| {
+            if a.is_pinned && !b.is_pinned {
+                std::cmp::Ordering::Less
+            } else if !a.is_pinned && b.is_pinned {
+                std::cmp::Ordering::Greater
+            } else {
+                b.timestamp.cmp(&a.timestamp)
+            }
+        });
+
+        // Both pinned first, sorted by timestamp
+        assert!(entries[0].is_pinned);
+        assert_eq!(entries[0].id, "3"); // pinned newer
+        assert!(entries[1].is_pinned);
+        assert_eq!(entries[1].id, "1"); // pinned older
+        // Then unpinned
+        assert!(!entries[2].is_pinned);
+        assert_eq!(entries[2].id, "2");
+    }
+
+    // ==================== Entry filtering tests ====================
+
+    #[test]
+    fn test_filter_entries_by_language() {
+        let history = ClipboardHistory {
+            entries: vec![
+                ClipboardEntry {
+                    id: "1".to_string(),
+                    content: "rust code".to_string(),
+                    language: Some("rust".to_string()),
+                    source: None,
+                    timestamp: "2024-01-01T00:00:00Z".to_string(),
+                    is_pinned: false,
+                },
+                ClipboardEntry {
+                    id: "2".to_string(),
+                    content: "js code".to_string(),
+                    language: Some("javascript".to_string()),
+                    source: None,
+                    timestamp: "2024-01-02T00:00:00Z".to_string(),
+                    is_pinned: false,
+                },
+                ClipboardEntry {
+                    id: "3".to_string(),
+                    content: "more rust".to_string(),
+                    language: Some("rust".to_string()),
+                    source: None,
+                    timestamp: "2024-01-03T00:00:00Z".to_string(),
+                    is_pinned: false,
+                },
+            ],
+        };
+
+        let filtered: Vec<_> = history
+            .entries
+            .iter()
+            .filter(|e| e.language.as_ref() == Some(&"rust".to_string()))
+            .collect();
+
+        assert_eq!(filtered.len(), 2);
+        assert!(filtered.iter().all(|e| e.language == Some("rust".to_string())));
+    }
+
+    #[test]
+    fn test_search_entries_by_content() {
+        let history = ClipboardHistory {
+            entries: vec![
+                ClipboardEntry {
+                    id: "1".to_string(),
+                    content: "fn hello_world()".to_string(),
+                    language: Some("rust".to_string()),
+                    source: None,
+                    timestamp: "2024-01-01T00:00:00Z".to_string(),
+                    is_pinned: false,
+                },
+                ClipboardEntry {
+                    id: "2".to_string(),
+                    content: "function hello()".to_string(),
+                    language: Some("javascript".to_string()),
+                    source: None,
+                    timestamp: "2024-01-02T00:00:00Z".to_string(),
+                    is_pinned: false,
+                },
+                ClipboardEntry {
+                    id: "3".to_string(),
+                    content: "def goodbye()".to_string(),
+                    language: Some("python".to_string()),
+                    source: None,
+                    timestamp: "2024-01-03T00:00:00Z".to_string(),
+                    is_pinned: false,
+                },
+            ],
+        };
+
+        let query = "hello";
+        let query_lower = query.to_lowercase();
+        let filtered: Vec<_> = history
+            .entries
+            .iter()
+            .filter(|e| e.content.to_lowercase().contains(&query_lower))
+            .collect();
+
+        assert_eq!(filtered.len(), 2);
+        assert!(filtered[0].content.contains("hello"));
+        assert!(filtered[1].content.contains("hello"));
+    }
+
+    #[test]
+    fn test_search_entries_case_insensitive() {
+        let history = ClipboardHistory {
+            entries: vec![
+                ClipboardEntry {
+                    id: "1".to_string(),
+                    content: "HELLO WORLD".to_string(),
+                    language: None,
+                    source: None,
+                    timestamp: "2024-01-01T00:00:00Z".to_string(),
+                    is_pinned: false,
+                },
+            ],
+        };
+
+        let query = "hello";
+        let query_lower = query.to_lowercase();
+        let filtered: Vec<_> = history
+            .entries
+            .iter()
+            .filter(|e| e.content.to_lowercase().contains(&query_lower))
+            .collect();
+
+        assert_eq!(filtered.len(), 1);
+    }
+
+    // ==================== Unique languages extraction test ====================
+
+    #[test]
+    fn test_extract_unique_languages() {
+        let history = ClipboardHistory {
+            entries: vec![
+                ClipboardEntry {
+                    id: "1".to_string(),
+                    content: "".to_string(),
+                    language: Some("rust".to_string()),
+                    source: None,
+                    timestamp: "".to_string(),
+                    is_pinned: false,
+                },
+                ClipboardEntry {
+                    id: "2".to_string(),
+                    content: "".to_string(),
+                    language: Some("javascript".to_string()),
+                    source: None,
+                    timestamp: "".to_string(),
+                    is_pinned: false,
+                },
+                ClipboardEntry {
+                    id: "3".to_string(),
+                    content: "".to_string(),
+                    language: Some("rust".to_string()), // Duplicate
+                    source: None,
+                    timestamp: "".to_string(),
+                    is_pinned: false,
+                },
+                ClipboardEntry {
+                    id: "4".to_string(),
+                    content: "".to_string(),
+                    language: None, // No language
+                    source: None,
+                    timestamp: "".to_string(),
+                    is_pinned: false,
+                },
+            ],
+        };
+
+        let mut languages: Vec<String> = history
+            .entries
+            .iter()
+            .filter_map(|e| e.language.clone())
+            .collect();
+        languages.sort();
+        languages.dedup();
+
+        assert_eq!(languages.len(), 2);
+        assert!(languages.contains(&"rust".to_string()));
+        assert!(languages.contains(&"javascript".to_string()));
+    }
+
+    // ==================== Retain pinned entries test ====================
+
+    #[test]
+    fn test_retain_pinned_on_clear() {
+        let mut history = ClipboardHistory {
+            entries: vec![
+                ClipboardEntry {
+                    id: "1".to_string(),
+                    content: "pinned".to_string(),
+                    language: None,
+                    source: None,
+                    timestamp: "".to_string(),
+                    is_pinned: true,
+                },
+                ClipboardEntry {
+                    id: "2".to_string(),
+                    content: "unpinned".to_string(),
+                    language: None,
+                    source: None,
+                    timestamp: "".to_string(),
+                    is_pinned: false,
+                },
+                ClipboardEntry {
+                    id: "3".to_string(),
+                    content: "another pinned".to_string(),
+                    language: None,
+                    source: None,
+                    timestamp: "".to_string(),
+                    is_pinned: true,
+                },
+            ],
+        };
+
+        // Simulate clear (keep only pinned)
+        history.entries.retain(|e| e.is_pinned);
+
+        assert_eq!(history.entries.len(), 2);
+        assert!(history.entries.iter().all(|e| e.is_pinned));
+    }
+}

src-tauri/src/commands.rs

@@ -393,3 +393,263 @@ pub async fn get_file_size(file_path: String) -> Result<u64, String> {
         .map_err(|e| format!("Failed to get file metadata: {}", e))?;
     Ok(metadata.len())
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::fs::{self, File};
+    use std::io::Write;
+    use tempfile::TempDir;
+
+    // Helper to run async tests
+    fn run_async<F: std::future::Future>(f: F) -> F::Output {
+        tokio::runtime::Runtime::new().unwrap().block_on(f)
+    }
+
+    // ==================== validate_directory tests ====================
+
+    #[test]
+    fn test_validate_directory_absolute_path_exists() {
+        let temp_dir = TempDir::new().unwrap();
+        let path = temp_dir.path().to_string_lossy().to_string();
+
+        let result = run_async(validate_directory(path.clone(), None));
+        assert!(result.is_ok());
+        // Canonicalized path should be returned
+        assert!(result.unwrap().contains(&temp_dir.path().file_name().unwrap().to_string_lossy().to_string()));
+    }
+
+    #[test]
+    fn test_validate_directory_path_not_exists() {
+        let result = run_async(validate_directory(
+            "/nonexistent/path/that/does/not/exist".to_string(),
+            None,
+        ));
+        assert!(result.is_err());
+        assert!(result.unwrap_err().contains("does not exist"));
+    }
+
+    #[test]
+    fn test_validate_directory_path_is_file() {
+        let temp_dir = TempDir::new().unwrap();
+        let file_path = temp_dir.path().join("test_file.txt");
+        File::create(&file_path).unwrap();
+
+        let result = run_async(validate_directory(
+            file_path.to_string_lossy().to_string(),
+            None,
+        ));
+        assert!(result.is_err());
+        assert!(result.unwrap_err().contains("not a directory"));
+    }
+
+    #[test]
+    fn test_validate_directory_home_expansion() {
+        // This test assumes HOME is set (which it should be on most systems)
+        if std::env::var_os("HOME").is_some() {
+            let result = run_async(validate_directory("~".to_string(), None));
+            assert!(result.is_ok());
+            // Should not contain ~ after expansion
+            assert!(!result.unwrap().contains("~"));
+        }
+    }
+
+    #[test]
+    fn test_validate_directory_home_subpath_expansion() {
+        // This test assumes HOME is set and has some subdirectory
+        if let Some(home) = std::env::var_os("HOME") {
+            let home_path = std::path::Path::new(&home);
+            // Find any subdirectory in home
+            if let Ok(entries) = fs::read_dir(home_path) {
+                for entry in entries.flatten() {
+                    if entry.path().is_dir() {
+                        let subdir_name = entry.file_name().to_string_lossy().to_string();
+                        let tilde_path = format!("~/{}", subdir_name);
+                        let result = run_async(validate_directory(tilde_path, None));
+                        assert!(result.is_ok());
+                        assert!(!result.unwrap().contains("~"));
+                        break;
+                    }
+                }
+            }
+        }
+    }
+
+    #[test]
+    fn test_validate_directory_relative_path_with_current_dir() {
+        let temp_dir = TempDir::new().unwrap();
+        let subdir = temp_dir.path().join("subdir");
+        fs::create_dir(&subdir).unwrap();
+
+        let result = run_async(validate_directory(
+            "subdir".to_string(),
+            Some(temp_dir.path().to_string_lossy().to_string()),
+        ));
+        assert!(result.is_ok());
+        assert!(result.unwrap().contains("subdir"));
+    }
+
+    #[test]
+    fn test_validate_directory_dot_path() {
+        let temp_dir = TempDir::new().unwrap();
+
+        let result = run_async(validate_directory(
+            ".".to_string(),
+            Some(temp_dir.path().to_string_lossy().to_string()),
+        ));
+        assert!(result.is_ok());
+    }
+
+    #[test]
+    fn test_validate_directory_dotdot_path() {
+        let temp_dir = TempDir::new().unwrap();
+        let subdir = temp_dir.path().join("subdir");
+        fs::create_dir(&subdir).unwrap();
+
+        let result = run_async(validate_directory(
+            "..".to_string(),
+            Some(subdir.to_string_lossy().to_string()),
+        ));
+        assert!(result.is_ok());
+        // Should resolve to parent
+        let resolved = result.unwrap();
+        assert!(resolved.contains(&temp_dir.path().file_name().unwrap().to_string_lossy().to_string()));
+    }
+
+    #[test]
+    fn test_validate_directory_relative_without_current_dir() {
+        // Relative path without current_dir - should fail since relative path likely won't exist
+        let result = run_async(validate_directory(
+            "some_random_nonexistent_relative_path".to_string(),
+            None,
+        ));
+        assert!(result.is_err());
+    }
+
+    // ==================== get_file_size tests ====================
+
+    #[test]
+    fn test_get_file_size_empty_file() {
+        let temp_dir = TempDir::new().unwrap();
+        let file_path = temp_dir.path().join("empty.txt");
+        File::create(&file_path).unwrap();
+
+        let result = run_async(get_file_size(file_path.to_string_lossy().to_string()));
+        assert!(result.is_ok());
+        assert_eq!(result.unwrap(), 0);
+    }
+
+    #[test]
+    fn test_get_file_size_with_content() {
+        let temp_dir = TempDir::new().unwrap();
+        let file_path = temp_dir.path().join("content.txt");
+        let mut file = File::create(&file_path).unwrap();
+        file.write_all(b"Hello, Hikari!").unwrap();
+
+        let result = run_async(get_file_size(file_path.to_string_lossy().to_string()));
+        assert!(result.is_ok());
+        assert_eq!(result.unwrap(), 14); // "Hello, Hikari!" is 14 bytes
+    }
+
+    #[test]
+    fn test_get_file_size_larger_file() {
+        let temp_dir = TempDir::new().unwrap();
+        let file_path = temp_dir.path().join("large.txt");
+        let mut file = File::create(&file_path).unwrap();
+        // Write 1000 bytes
+        let data = vec![b'x'; 1000];
+        file.write_all(&data).unwrap();
+
+        let result = run_async(get_file_size(file_path.to_string_lossy().to_string()));
+        assert!(result.is_ok());
+        assert_eq!(result.unwrap(), 1000);
+    }
+
+    #[test]
+    fn test_get_file_size_nonexistent_file() {
+        let result = run_async(get_file_size(
+            "/nonexistent/path/file.txt".to_string(),
+        ));
+        assert!(result.is_err());
+        assert!(result.unwrap_err().contains("Failed to get file metadata"));
+    }
+
+    #[test]
+    fn test_get_file_size_directory() {
+        let temp_dir = TempDir::new().unwrap();
+
+        // Getting "size" of a directory should work but return directory metadata
+        // This is actually valid - directories have metadata too
+        let result = run_async(get_file_size(temp_dir.path().to_string_lossy().to_string()));
+        assert!(result.is_ok());
+        // Directory size is platform-dependent, just check it returns something
+    }
+
+    // ==================== list_skills tests ====================
+
+    #[test]
+    fn test_list_skills_no_skills_dir() {
+        // This test is tricky because it depends on HOME being set
+        // and potentially affecting real user data, so we'll just
+        // verify the function doesn't panic
+        let result = run_async(list_skills());
+        // Should either return Ok with a list or Ok with empty vec
+        assert!(result.is_ok());
+    }
+
+    // ==================== select_wsl_directory tests ====================
+
+    #[test]
+    fn test_select_wsl_directory_returns_home() {
+        let result = run_async(select_wsl_directory());
+        assert!(result.is_ok());
+        assert_eq!(result.unwrap(), "/home");
+    }
+
+    // ==================== UpdateInfo struct tests ====================
+
+    #[test]
+    fn test_update_info_serialization() {
+        let info = UpdateInfo {
+            current_version: "0.3.0".to_string(),
+            latest_version: "0.4.0".to_string(),
+            has_update: true,
+            release_url: "https://example.com/release".to_string(),
+            release_notes: Some("New features!".to_string()),
+        };
+
+        let json = serde_json::to_string(&info).unwrap();
+        assert!(json.contains("0.3.0"));
+        assert!(json.contains("0.4.0"));
+        assert!(json.contains("true"));
+        assert!(json.contains("New features!"));
+    }
+
+    #[test]
+    fn test_update_info_without_notes() {
+        let info = UpdateInfo {
+            current_version: "0.3.0".to_string(),
+            latest_version: "0.3.0".to_string(),
+            has_update: false,
+            release_url: "https://example.com/release".to_string(),
+            release_notes: None,
+        };
+
+        let json = serde_json::to_string(&info).unwrap();
+        assert!(json.contains("null") || json.contains("release_notes"));
+    }
+
+    // ==================== SavedFileInfo struct tests ====================
+
+    #[test]
+    fn test_saved_file_info_serialization() {
+        let info = SavedFileInfo {
+            path: "/tmp/test.txt".to_string(),
+            filename: "test.txt".to_string(),
+        };
+
+        let json = serde_json::to_string(&info).unwrap();
+        assert!(json.contains("/tmp/test.txt"));
+        assert!(json.contains("test.txt"));
+    }
+}

src-tauri/src/git.rs

@@ -286,3 +286,593 @@ pub fn git_discard(working_dir: String, file_path: String) -> Result<String, Str
 pub fn git_create_branch(working_dir: String, branch_name: String) -> Result<String, String> {
     run_git_command(&working_dir, &["checkout", "-b", &branch_name])
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::fs::{self, File};
+    use std::io::Write;
+    use tempfile::TempDir;
+
+    // Helper to create a git repository in a temp directory
+    fn create_test_repo() -> TempDir {
+        let temp_dir = TempDir::new().unwrap();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        // Initialize git repo
+        run_git_command(&working_dir, &["init"]).unwrap();
+
+        // Configure git user for commits
+        run_git_command(&working_dir, &["config", "user.email", "test@example.com"]).unwrap();
+        run_git_command(&working_dir, &["config", "user.name", "Test User"]).unwrap();
+
+        // Disable GPG signing for tests (user may have it enabled globally)
+        run_git_command(&working_dir, &["config", "commit.gpgsign", "false"]).unwrap();
+
+        temp_dir
+    }
+
+    // Helper to create a file in the test repo
+    fn create_file(dir: &TempDir, name: &str, content: &str) {
+        let file_path = dir.path().join(name);
+        let mut file = File::create(file_path).unwrap();
+        file.write_all(content.as_bytes()).unwrap();
+    }
+
+    // ==================== GitStatus struct tests ====================
+
+    #[test]
+    fn test_git_status_serialization() {
+        let status = GitStatus {
+            is_repo: true,
+            branch: Some("main".to_string()),
+            upstream: Some("origin/main".to_string()),
+            ahead: 2,
+            behind: 1,
+            staged: vec![GitFileChange {
+                path: "file.txt".to_string(),
+                status: "modified".to_string(),
+            }],
+            unstaged: vec![],
+            untracked: vec!["new_file.txt".to_string()],
+        };
+
+        let json = serde_json::to_string(&status).unwrap();
+        assert!(json.contains("\"is_repo\":true"));
+        assert!(json.contains("\"branch\":\"main\""));
+        assert!(json.contains("\"ahead\":2"));
+        assert!(json.contains("\"behind\":1"));
+    }
+
+    #[test]
+    fn test_git_status_not_a_repo() {
+        let status = GitStatus {
+            is_repo: false,
+            branch: None,
+            upstream: None,
+            ahead: 0,
+            behind: 0,
+            staged: vec![],
+            unstaged: vec![],
+            untracked: vec![],
+        };
+
+        let json = serde_json::to_string(&status).unwrap();
+        let deserialized: GitStatus = serde_json::from_str(&json).unwrap();
+        assert!(!deserialized.is_repo);
+        assert!(deserialized.branch.is_none());
+    }
+
+    // ==================== GitFileChange struct tests ====================
+
+    #[test]
+    fn test_git_file_change_serialization() {
+        let change = GitFileChange {
+            path: "src/main.rs".to_string(),
+            status: "added".to_string(),
+        };
+
+        let json = serde_json::to_string(&change).unwrap();
+        assert!(json.contains("src/main.rs"));
+        assert!(json.contains("added"));
+
+        let deserialized: GitFileChange = serde_json::from_str(&json).unwrap();
+        assert_eq!(deserialized.path, "src/main.rs");
+        assert_eq!(deserialized.status, "added");
+    }
+
+    // ==================== GitBranch struct tests ====================
+
+    #[test]
+    fn test_git_branch_serialization() {
+        let branch = GitBranch {
+            name: "feature/new-feature".to_string(),
+            is_current: true,
+            is_remote: false,
+        };
+
+        let json = serde_json::to_string(&branch).unwrap();
+        assert!(json.contains("feature/new-feature"));
+        assert!(json.contains("\"is_current\":true"));
+        assert!(json.contains("\"is_remote\":false"));
+    }
+
+    #[test]
+    fn test_git_branch_remote() {
+        let branch = GitBranch {
+            name: "origin/main".to_string(),
+            is_current: false,
+            is_remote: true,
+        };
+
+        let json = serde_json::to_string(&branch).unwrap();
+        let deserialized: GitBranch = serde_json::from_str(&json).unwrap();
+        assert!(deserialized.is_remote);
+        assert!(!deserialized.is_current);
+    }
+
+    // ==================== GitLogEntry struct tests ====================
+
+    #[test]
+    fn test_git_log_entry_serialization() {
+        let entry = GitLogEntry {
+            hash: "abc123def456".to_string(),
+            short_hash: "abc123d".to_string(),
+            author: "Hikari".to_string(),
+            date: "2 hours ago".to_string(),
+            message: "feat: add new feature".to_string(),
+        };
+
+        let json = serde_json::to_string(&entry).unwrap();
+        assert!(json.contains("abc123def456"));
+        assert!(json.contains("Hikari"));
+        assert!(json.contains("feat: add new feature"));
+    }
+
+    // ==================== git_status integration tests ====================
+
+    #[test]
+    fn test_git_status_not_a_git_repo() {
+        let temp_dir = TempDir::new().unwrap();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        let result = git_status(working_dir);
+        assert!(result.is_ok());
+
+        let status = result.unwrap();
+        assert!(!status.is_repo);
+        assert!(status.branch.is_none());
+        assert!(status.staged.is_empty());
+    }
+
+    #[test]
+    fn test_git_status_empty_repo() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        let result = git_status(working_dir);
+        assert!(result.is_ok());
+
+        let status = result.unwrap();
+        assert!(status.is_repo);
+        assert!(status.staged.is_empty());
+        assert!(status.unstaged.is_empty());
+        assert!(status.untracked.is_empty());
+    }
+
+    #[test]
+    fn test_git_status_with_untracked_file() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        // Create an untracked file
+        create_file(&temp_dir, "untracked.txt", "hello");
+
+        let result = git_status(working_dir);
+        assert!(result.is_ok());
+
+        let status = result.unwrap();
+        assert!(status.is_repo);
+        assert!(status.untracked.contains(&"untracked.txt".to_string()));
+    }
+
+    #[test]
+    fn test_git_status_with_staged_file() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        // Create and stage a file
+        create_file(&temp_dir, "staged.txt", "hello");
+        run_git_command(&working_dir, &["add", "staged.txt"]).unwrap();
+
+        let result = git_status(working_dir);
+        assert!(result.is_ok());
+
+        let status = result.unwrap();
+        assert!(status.is_repo);
+        assert!(!status.staged.is_empty());
+        assert_eq!(status.staged[0].path, "staged.txt");
+        assert_eq!(status.staged[0].status, "added");
+    }
+
+    #[test]
+    fn test_git_status_with_modified_file() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        // Create, stage, and commit a file
+        create_file(&temp_dir, "file.txt", "initial content");
+        run_git_command(&working_dir, &["add", "file.txt"]).unwrap();
+        run_git_command(&working_dir, &["commit", "-m", "initial commit"]).unwrap();
+
+        // Modify the file
+        create_file(&temp_dir, "file.txt", "modified content");
+
+        let result = git_status(working_dir);
+        assert!(result.is_ok());
+
+        let status = result.unwrap();
+        assert!(status.is_repo);
+        assert!(!status.unstaged.is_empty());
+        assert_eq!(status.unstaged[0].path, "file.txt");
+        assert_eq!(status.unstaged[0].status, "modified");
+    }
+
+    // ==================== git_diff integration tests ====================
+
+    #[test]
+    fn test_git_diff_no_changes() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        let result = git_diff(working_dir, None, false);
+        assert!(result.is_ok());
+        assert!(result.unwrap().is_empty());
+    }
+
+    #[test]
+    fn test_git_diff_with_changes() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        // Create and commit a file
+        create_file(&temp_dir, "file.txt", "initial content");
+        run_git_command(&working_dir, &["add", "file.txt"]).unwrap();
+        run_git_command(&working_dir, &["commit", "-m", "initial"]).unwrap();
+
+        // Modify the file
+        create_file(&temp_dir, "file.txt", "modified content");
+
+        let result = git_diff(working_dir, None, false);
+        assert!(result.is_ok());
+        let diff = result.unwrap();
+        assert!(diff.contains("diff"));
+        assert!(diff.contains("file.txt"));
+    }
+
+    #[test]
+    fn test_git_diff_staged() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        // Create and commit a file
+        create_file(&temp_dir, "file.txt", "initial content");
+        run_git_command(&working_dir, &["add", "file.txt"]).unwrap();
+        run_git_command(&working_dir, &["commit", "-m", "initial"]).unwrap();
+
+        // Modify and stage the file
+        create_file(&temp_dir, "file.txt", "modified content");
+        run_git_command(&working_dir, &["add", "file.txt"]).unwrap();
+
+        let result = git_diff(working_dir, None, true);
+        assert!(result.is_ok());
+        let diff = result.unwrap();
+        assert!(diff.contains("diff"));
+    }
+
+    #[test]
+    fn test_git_diff_specific_file() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        // Create and commit files
+        create_file(&temp_dir, "file1.txt", "content1");
+        create_file(&temp_dir, "file2.txt", "content2");
+        run_git_command(&working_dir, &["add", "-A"]).unwrap();
+        run_git_command(&working_dir, &["commit", "-m", "initial"]).unwrap();
+
+        // Modify both files
+        create_file(&temp_dir, "file1.txt", "modified1");
+        create_file(&temp_dir, "file2.txt", "modified2");
+
+        // Get diff for only file1.txt
+        let result = git_diff(working_dir, Some("file1.txt".to_string()), false);
+        assert!(result.is_ok());
+        let diff = result.unwrap();
+        assert!(diff.contains("file1.txt"));
+        assert!(!diff.contains("file2.txt"));
+    }
+
+    // ==================== git_branches integration tests ====================
+
+    #[test]
+    fn test_git_branches_single_branch() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        // Need at least one commit for branches to show
+        create_file(&temp_dir, "file.txt", "content");
+        run_git_command(&working_dir, &["add", "file.txt"]).unwrap();
+        run_git_command(&working_dir, &["commit", "-m", "initial"]).unwrap();
+
+        let result = git_branches(working_dir);
+        assert!(result.is_ok());
+
+        let branches = result.unwrap();
+        assert!(!branches.is_empty());
+        // Should have at least one branch (main or master)
+    }
+
+    #[test]
+    fn test_git_branches_multiple_branches() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        // Initial commit
+        create_file(&temp_dir, "file.txt", "content");
+        run_git_command(&working_dir, &["add", "file.txt"]).unwrap();
+        run_git_command(&working_dir, &["commit", "-m", "initial"]).unwrap();
+
+        // Create additional branch
+        run_git_command(&working_dir, &["branch", "feature-branch"]).unwrap();
+
+        let result = git_branches(working_dir);
+        assert!(result.is_ok());
+
+        let branches = result.unwrap();
+        assert!(branches.len() >= 2);
+        assert!(branches.iter().any(|b| b.name == "feature-branch"));
+    }
+
+    // ==================== git_stage and git_unstage tests ====================
+
+    #[test]
+    fn test_git_stage_file() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        create_file(&temp_dir, "file.txt", "content");
+
+        let result = git_stage(working_dir.clone(), "file.txt".to_string());
+        assert!(result.is_ok());
+
+        // Verify file is staged
+        let status = git_status(working_dir).unwrap();
+        assert!(status.staged.iter().any(|f| f.path == "file.txt"));
+    }
+
+    #[test]
+    fn test_git_unstage_file() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        // First, commit a file so we have a HEAD to restore from
+        create_file(&temp_dir, "file.txt", "initial content");
+        run_git_command(&working_dir, &["add", "file.txt"]).unwrap();
+        run_git_command(&working_dir, &["commit", "-m", "initial"]).unwrap();
+
+        // Modify and stage the file
+        create_file(&temp_dir, "file.txt", "modified content");
+        run_git_command(&working_dir, &["add", "file.txt"]).unwrap();
+
+        let result = git_unstage(working_dir.clone(), "file.txt".to_string());
+        assert!(result.is_ok());
+
+        // Verify file is unstaged (should now be in unstaged/modified, not staged)
+        let status = git_status(working_dir).unwrap();
+        assert!(!status.staged.iter().any(|f| f.path == "file.txt"));
+        assert!(status.unstaged.iter().any(|f| f.path == "file.txt"));
+    }
+
+    #[test]
+    fn test_git_stage_all() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        create_file(&temp_dir, "file1.txt", "content1");
+        create_file(&temp_dir, "file2.txt", "content2");
+
+        let result = git_stage_all(working_dir.clone());
+        assert!(result.is_ok());
+
+        // Verify all files are staged
+        let status = git_status(working_dir).unwrap();
+        assert_eq!(status.staged.len(), 2);
+    }
+
+    // ==================== git_commit tests ====================
+
+    #[test]
+    fn test_git_commit() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        create_file(&temp_dir, "file.txt", "content");
+        run_git_command(&working_dir, &["add", "file.txt"]).unwrap();
+
+        let result = git_commit(working_dir.clone(), "test commit message".to_string());
+        assert!(result.is_ok());
+
+        // Verify commit was made
+        let log = git_log(working_dir, Some(1)).unwrap();
+        assert!(!log.is_empty());
+        assert!(log[0].message.contains("test commit message"));
+    }
+
+    #[test]
+    fn test_git_commit_nothing_to_commit() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        // Need initial commit first
+        create_file(&temp_dir, "file.txt", "content");
+        run_git_command(&working_dir, &["add", "file.txt"]).unwrap();
+        run_git_command(&working_dir, &["commit", "-m", "initial"]).unwrap();
+
+        // Try to commit with nothing staged
+        let result = git_commit(working_dir, "empty commit".to_string());
+        assert!(result.is_err()); // Should fail because nothing to commit
+    }
+
+    // ==================== git_log tests ====================
+
+    #[test]
+    fn test_git_log_empty_repo() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        let result = git_log(working_dir, Some(10));
+        // May fail on empty repo or return empty
+        if let Ok(commits) = result {
+            assert!(commits.is_empty());
+        }
+    }
+
+    #[test]
+    fn test_git_log_with_commits() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        // Make multiple commits
+        for i in 1..=3 {
+            create_file(&temp_dir, &format!("file{}.txt", i), "content");
+            run_git_command(&working_dir, &["add", "-A"]).unwrap();
+            run_git_command(&working_dir, &["commit", "-m", &format!("commit {}", i)]).unwrap();
+        }
+
+        let result = git_log(working_dir, Some(10));
+        assert!(result.is_ok());
+
+        let log = result.unwrap();
+        assert_eq!(log.len(), 3);
+        assert!(log[0].message.contains("commit 3")); // Most recent first
+        assert!(log[2].message.contains("commit 1"));
+    }
+
+    #[test]
+    fn test_git_log_limit() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        // Make 5 commits
+        for i in 1..=5 {
+            create_file(&temp_dir, &format!("file{}.txt", i), "content");
+            run_git_command(&working_dir, &["add", "-A"]).unwrap();
+            run_git_command(&working_dir, &["commit", "-m", &format!("commit {}", i)]).unwrap();
+        }
+
+        // Only get last 2
+        let result = git_log(working_dir, Some(2));
+        assert!(result.is_ok());
+
+        let log = result.unwrap();
+        assert_eq!(log.len(), 2);
+    }
+
+    // ==================== git_discard tests ====================
+
+    #[test]
+    fn test_git_discard_changes() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        // Create and commit a file
+        create_file(&temp_dir, "file.txt", "original content");
+        run_git_command(&working_dir, &["add", "file.txt"]).unwrap();
+        run_git_command(&working_dir, &["commit", "-m", "initial"]).unwrap();
+
+        // Modify the file
+        create_file(&temp_dir, "file.txt", "modified content");
+
+        // Discard changes
+        let result = git_discard(working_dir.clone(), "file.txt".to_string());
+        assert!(result.is_ok());
+
+        // Verify file contents are restored
+        let content = fs::read_to_string(temp_dir.path().join("file.txt")).unwrap();
+        assert_eq!(content, "original content");
+    }
+
+    // ==================== git_create_branch tests ====================
+
+    #[test]
+    fn test_git_create_branch() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        // Initial commit required
+        create_file(&temp_dir, "file.txt", "content");
+        run_git_command(&working_dir, &["add", "file.txt"]).unwrap();
+        run_git_command(&working_dir, &["commit", "-m", "initial"]).unwrap();
+
+        let result = git_create_branch(working_dir.clone(), "new-branch".to_string());
+        assert!(result.is_ok());
+
+        // Verify branch exists and is current
+        let branches = git_branches(working_dir).unwrap();
+        assert!(branches.iter().any(|b| b.name == "new-branch" && b.is_current));
+    }
+
+    // ==================== git_checkout tests ====================
+
+    #[test]
+    fn test_git_checkout() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        // Initial commit required
+        create_file(&temp_dir, "file.txt", "content");
+        run_git_command(&working_dir, &["add", "file.txt"]).unwrap();
+        run_git_command(&working_dir, &["commit", "-m", "initial"]).unwrap();
+
+        // Create a branch
+        run_git_command(&working_dir, &["branch", "other-branch"]).unwrap();
+
+        // Checkout the branch
+        let result = git_checkout(working_dir.clone(), "other-branch".to_string());
+        assert!(result.is_ok());
+
+        // Verify current branch
+        let branches = git_branches(working_dir).unwrap();
+        let current = branches.iter().find(|b| b.is_current);
+        assert!(current.is_some());
+        assert_eq!(current.unwrap().name, "other-branch");
+    }
+
+    // ==================== run_git_command tests ====================
+
+    #[test]
+    fn test_run_git_command_success() {
+        let temp_dir = create_test_repo();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        let result = run_git_command(&working_dir, &["status"]);
+        assert!(result.is_ok());
+    }
+
+    #[test]
+    fn test_run_git_command_failure() {
+        let temp_dir = TempDir::new().unwrap();
+        let working_dir = temp_dir.path().to_string_lossy().to_string();
+
+        // This should fail because it's not a git repo
+        let result = run_git_command(&working_dir, &["log"]);
+        assert!(result.is_err());
+    }
+
+    #[test]
+    fn test_run_git_command_invalid_dir() {
+        let result = run_git_command("/nonexistent/path", &["status"]);
+        assert!(result.is_err());
+    }
+}

src-tauri/src/quick_actions.rs

@@ -171,6 +171,18 @@ pub async fn reset_default_quick_actions(app: AppHandle) -> Result<(), String> {
 mod tests {
     use super::*;
 
+    fn create_test_action(id: &str, name: &str, is_default: bool) -> QuickAction {
+        QuickAction {
+            id: id.to_string(),
+            name: name.to_string(),
+            prompt: "Test prompt".to_string(),
+            icon: "star".to_string(),
+            is_default,
+            created_at: Utc::now(),
+            updated_at: Utc::now(),
+        }
+    }
+
     #[test]
     fn test_default_quick_actions_exist() {
         let defaults = get_default_quick_actions();
@@ -188,4 +200,174 @@ mod tests {
             assert!(!action.icon.is_empty());
         }
     }
+
+    #[test]
+    fn test_default_quick_actions_count() {
+        let defaults = get_default_quick_actions();
+        // Should have 6 default actions
+        assert_eq!(defaults.len(), 6);
+    }
+
+    #[test]
+    fn test_default_quick_actions_have_unique_ids() {
+        let defaults = get_default_quick_actions();
+        let mut ids: Vec<&String> = defaults.iter().map(|a| &a.id).collect();
+        ids.sort();
+        ids.dedup();
+        assert_eq!(ids.len(), defaults.len());
+    }
+
+    #[test]
+    fn test_default_quick_actions_ids_start_with_default() {
+        let defaults = get_default_quick_actions();
+        assert!(defaults.iter().all(|a| a.id.starts_with("default-")));
+    }
+
+    #[test]
+    fn test_quick_action_serialization() {
+        let action = create_test_action("test-1", "Test Action", false);
+        let json = serde_json::to_string(&action).expect("Failed to serialize");
+        let parsed: QuickAction = serde_json::from_str(&json).expect("Failed to deserialize");
+
+        assert_eq!(parsed.id, action.id);
+        assert_eq!(parsed.name, action.name);
+        assert_eq!(parsed.prompt, action.prompt);
+        assert_eq!(parsed.icon, action.icon);
+        assert_eq!(parsed.is_default, action.is_default);
+    }
+
+    #[test]
+    fn test_quick_action_clone() {
+        let original = create_test_action("clone-test", "Clone Test", true);
+        let cloned = original.clone();
+
+        assert_eq!(original.id, cloned.id);
+        assert_eq!(original.name, cloned.name);
+        assert_eq!(original.is_default, cloned.is_default);
+    }
+
+    #[test]
+    #[allow(clippy::useless_vec)]
+    fn test_quick_action_sorting_defaults_first() {
+        let mut actions = vec![
+            create_test_action("custom-z", "Zebra", false),
+            create_test_action("default-a", "Apple", true),
+            create_test_action("custom-a", "Alpha", false),
+            create_test_action("default-z", "Zulu", true),
+        ];
+
+        // Sort by: defaults first, then alphabetically by name
+        actions.sort_by(|a, b| {
+            let default_cmp = b.is_default.cmp(&a.is_default);
+            if default_cmp == std::cmp::Ordering::Equal {
+                a.name.cmp(&b.name)
+            } else {
+                default_cmp
+            }
+        });
+
+        // Defaults should come first
+        assert!(actions[0].is_default);
+        assert!(actions[1].is_default);
+        assert!(!actions[2].is_default);
+        assert!(!actions[3].is_default);
+
+        // Within defaults, alphabetically sorted
+        assert_eq!(actions[0].name, "Apple");
+        assert_eq!(actions[1].name, "Zulu");
+
+        // Within non-defaults, alphabetically sorted
+        assert_eq!(actions[2].name, "Alpha");
+        assert_eq!(actions[3].name, "Zebra");
+    }
+
+    #[test]
+    fn test_known_default_actions() {
+        let defaults = get_default_quick_actions();
+        let ids: Vec<&str> = defaults.iter().map(|a| a.id.as_str()).collect();
+
+        assert!(ids.contains(&"default-review-pr"));
+        assert!(ids.contains(&"default-run-tests"));
+        assert!(ids.contains(&"default-explain-file"));
+        assert!(ids.contains(&"default-fix-error"));
+        assert!(ids.contains(&"default-write-tests"));
+        assert!(ids.contains(&"default-refactor"));
+    }
+
+    #[test]
+    fn test_default_action_icons() {
+        let defaults = get_default_quick_actions();
+        let icons: Vec<&str> = defaults.iter().map(|a| a.icon.as_str()).collect();
+
+        assert!(icons.contains(&"git-pull-request"));
+        assert!(icons.contains(&"play"));
+        assert!(icons.contains(&"file-text"));
+        assert!(icons.contains(&"alert-circle"));
+        assert!(icons.contains(&"check-square"));
+        assert!(icons.contains(&"refresh-cw"));
+    }
+
+    #[test]
+    fn test_quick_action_prompts_not_empty() {
+        let defaults = get_default_quick_actions();
+        for action in defaults {
+            assert!(
+                action.prompt.len() > 10,
+                "Prompt should be meaningful: {}",
+                action.name
+            );
+        }
+    }
+
+    #[test]
+    fn test_quick_action_timestamps() {
+        let action = create_test_action("time-test", "Time Test", false);
+        assert!(action.created_at <= action.updated_at);
+    }
+
+    #[test]
+    fn test_default_actions_have_same_timestamps() {
+        let defaults = get_default_quick_actions();
+        // All defaults are created at the same instant
+        let first_created = defaults[0].created_at;
+        let first_updated = defaults[0].updated_at;
+
+        for action in &defaults {
+            assert_eq!(action.created_at, first_created);
+            assert_eq!(action.updated_at, first_updated);
+        }
+    }
+
+    #[test]
+    fn test_action_retain_non_default() {
+        let mut actions = vec![
+            create_test_action("default-1", "Default 1", true),
+            create_test_action("custom-1", "Custom 1", false),
+            create_test_action("default-2", "Default 2", true),
+            create_test_action("custom-2", "Custom 2", false),
+        ];
+
+        // Mimics reset_default_quick_actions behavior (retain non-defaults)
+        actions.retain(|a| !a.is_default);
+
+        assert_eq!(actions.len(), 2);
+        assert!(actions.iter().all(|a| !a.is_default));
+    }
+
+    #[test]
+    #[allow(clippy::useless_vec)]
+    fn test_action_find_by_id() {
+        let actions = vec![
+            create_test_action("action-1", "First", false),
+            create_test_action("action-2", "Second", false),
+            create_test_action("action-3", "Third", false),
+        ];
+
+        let found = actions.iter().find(|a| a.id == "action-2");
+        assert!(found.is_some());
+        assert_eq!(found.unwrap().name, "Second");
+
+        let not_found = actions.iter().find(|a| a.id == "action-999");
+        assert!(not_found.is_none());
+    }
 }

src-tauri/src/sessions.rs

@@ -145,6 +145,30 @@ pub async fn clear_all_sessions(app: AppHandle) -> Result<(), String> {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use chrono::TimeZone;
+
+    fn create_test_session(id: &str, name: &str) -> SavedSession {
+        SavedSession {
+            id: id.to_string(),
+            name: name.to_string(),
+            created_at: Utc::now(),
+            last_activity_at: Utc::now(),
+            working_directory: "/home/test".to_string(),
+            message_count: 5,
+            preview: "Hello world".to_string(),
+            messages: vec![],
+        }
+    }
+
+    fn create_test_message(id: &str, content: &str, msg_type: &str) -> SavedMessage {
+        SavedMessage {
+            id: id.to_string(),
+            message_type: msg_type.to_string(),
+            content: content.to_string(),
+            timestamp: Utc::now(),
+            tool_name: None,
+        }
+    }
 
     #[test]
     fn test_session_list_item_from_saved_session() {
@@ -164,4 +188,187 @@ mod tests {
         assert_eq!(item.name, "Test Session");
         assert_eq!(item.message_count, 5);
     }
+
+    #[test]
+    fn test_session_list_item_preserves_all_fields() {
+        let created = Utc.with_ymd_and_hms(2024, 1, 15, 10, 30, 0).unwrap();
+        let last_activity = Utc.with_ymd_and_hms(2024, 1, 15, 14, 45, 0).unwrap();
+
+        let session = SavedSession {
+            id: "sess-123".to_string(),
+            name: "My Chat".to_string(),
+            created_at: created,
+            last_activity_at: last_activity,
+            working_directory: "/home/naomi/project".to_string(),
+            message_count: 42,
+            preview: "What is the meaning of life?".to_string(),
+            messages: vec![],
+        };
+
+        let item = SessionListItem::from(&session);
+
+        assert_eq!(item.id, "sess-123");
+        assert_eq!(item.name, "My Chat");
+        assert_eq!(item.created_at, created);
+        assert_eq!(item.last_activity_at, last_activity);
+        assert_eq!(item.working_directory, "/home/naomi/project");
+        assert_eq!(item.message_count, 42);
+        assert_eq!(item.preview, "What is the meaning of life?");
+    }
+
+    #[test]
+    fn test_saved_session_serialization() {
+        let session = create_test_session("test-1", "Test Session");
+        let json = serde_json::to_string(&session).expect("Failed to serialize");
+        let parsed: SavedSession = serde_json::from_str(&json).expect("Failed to deserialize");
+
+        assert_eq!(parsed.id, session.id);
+        assert_eq!(parsed.name, session.name);
+        assert_eq!(parsed.working_directory, session.working_directory);
+    }
+
+    #[test]
+    fn test_saved_message_serialization() {
+        let message = create_test_message("msg-1", "Hello!", "user");
+        let json = serde_json::to_string(&message).expect("Failed to serialize");
+        let parsed: SavedMessage = serde_json::from_str(&json).expect("Failed to deserialize");
+
+        assert_eq!(parsed.id, message.id);
+        assert_eq!(parsed.content, message.content);
+        assert_eq!(parsed.message_type, "user");
+    }
+
+    #[test]
+    fn test_saved_message_with_tool_name() {
+        let message = SavedMessage {
+            id: "msg-tool-1".to_string(),
+            message_type: "tool".to_string(),
+            content: "File read successfully".to_string(),
+            timestamp: Utc::now(),
+            tool_name: Some("Read".to_string()),
+        };
+
+        let json = serde_json::to_string(&message).expect("Failed to serialize");
+        let parsed: SavedMessage = serde_json::from_str(&json).expect("Failed to deserialize");
+
+        assert_eq!(parsed.tool_name, Some("Read".to_string()));
+    }
+
+    #[test]
+    fn test_session_with_messages_serialization() {
+        let mut session = create_test_session("sess-full", "Full Session");
+        session.messages = vec![
+            create_test_message("msg-1", "Hello!", "user"),
+            create_test_message("msg-2", "Hi there!", "assistant"),
+            create_test_message("msg-3", "Read file", "tool"),
+        ];
+        session.message_count = 3;
+
+        let json = serde_json::to_string(&session).expect("Failed to serialize");
+        let parsed: SavedSession = serde_json::from_str(&json).expect("Failed to deserialize");
+
+        assert_eq!(parsed.messages.len(), 3);
+        assert_eq!(parsed.messages[0].content, "Hello!");
+        assert_eq!(parsed.messages[1].message_type, "assistant");
+        assert_eq!(parsed.messages[2].message_type, "tool");
+    }
+
+    #[test]
+    fn test_session_list_item_serialization() {
+        let item = SessionListItem {
+            id: "list-item-1".to_string(),
+            name: "Quick Chat".to_string(),
+            created_at: Utc::now(),
+            last_activity_at: Utc::now(),
+            working_directory: "/tmp".to_string(),
+            message_count: 10,
+            preview: "Short preview...".to_string(),
+        };
+
+        let json = serde_json::to_string(&item).expect("Failed to serialize");
+        let parsed: SessionListItem = serde_json::from_str(&json).expect("Failed to deserialize");
+
+        assert_eq!(parsed.id, item.id);
+        assert_eq!(parsed.name, item.name);
+        assert_eq!(parsed.preview, item.preview);
+    }
+
+    #[test]
+    fn test_message_type_field_rename() {
+        // The message_type field is renamed to "type" in JSON
+        let message = create_test_message("msg-1", "Test", "assistant");
+        let json = serde_json::to_string(&message).expect("Failed to serialize");
+
+        assert!(json.contains("\"type\":"));
+        assert!(!json.contains("\"message_type\":"));
+    }
+
+    #[test]
+    fn test_session_default_empty_messages() {
+        let session = SavedSession {
+            id: "empty".to_string(),
+            name: "Empty".to_string(),
+            created_at: Utc::now(),
+            last_activity_at: Utc::now(),
+            working_directory: "/".to_string(),
+            message_count: 0,
+            preview: "".to_string(),
+            messages: vec![],
+        };
+
+        assert!(session.messages.is_empty());
+        assert_eq!(session.message_count, 0);
+    }
+
+    #[test]
+    #[allow(clippy::useless_vec)]
+    fn test_session_sorting_by_activity() {
+        let old_time = Utc.with_ymd_and_hms(2024, 1, 1, 0, 0, 0).unwrap();
+        let new_time = Utc.with_ymd_and_hms(2024, 6, 15, 12, 0, 0).unwrap();
+
+        let mut sessions = vec![
+            SessionListItem {
+                id: "old".to_string(),
+                name: "Old Session".to_string(),
+                created_at: old_time,
+                last_activity_at: old_time,
+                working_directory: "/old".to_string(),
+                message_count: 1,
+                preview: "Old".to_string(),
+            },
+            SessionListItem {
+                id: "new".to_string(),
+                name: "New Session".to_string(),
+                created_at: new_time,
+                last_activity_at: new_time,
+                working_directory: "/new".to_string(),
+                message_count: 1,
+                preview: "New".to_string(),
+            },
+        ];
+
+        // Sort by last activity, most recent first (mimics list_sessions behavior)
+        sessions.sort_by(|a, b| b.last_activity_at.cmp(&a.last_activity_at));
+
+        assert_eq!(sessions[0].id, "new");
+        assert_eq!(sessions[1].id, "old");
+    }
+
+    #[test]
+    fn test_session_clone() {
+        let original = create_test_session("clone-test", "Clone Test");
+        let cloned = original.clone();
+
+        assert_eq!(original.id, cloned.id);
+        assert_eq!(original.name, cloned.name);
+    }
+
+    #[test]
+    fn test_message_clone() {
+        let original = create_test_message("msg-clone", "Content", "user");
+        let cloned = original.clone();
+
+        assert_eq!(original.id, cloned.id);
+        assert_eq!(original.content, cloned.content);
+    }
 }

src-tauri/src/snippets.rs

@@ -205,6 +205,19 @@ pub async fn reset_default_snippets(app: AppHandle) -> Result<(), String> {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use std::collections::HashSet;
+
+    fn create_test_snippet(id: &str, name: &str, category: &str, is_default: bool) -> Snippet {
+        Snippet {
+            id: id.to_string(),
+            name: name.to_string(),
+            content: "Test content".to_string(),
+            category: category.to_string(),
+            is_default,
+            created_at: Utc::now(),
+            updated_at: Utc::now(),
+        }
+    }
 
     #[test]
     fn test_default_snippets_exist() {
@@ -223,4 +236,204 @@ mod tests {
             assert!(!snippet.category.is_empty());
         }
     }
+
+    #[test]
+    fn test_default_snippets_count() {
+        let defaults = get_default_snippets();
+        // Should have 8 default snippets
+        assert_eq!(defaults.len(), 8);
+    }
+
+    #[test]
+    fn test_default_snippets_have_unique_ids() {
+        let defaults = get_default_snippets();
+        let ids: HashSet<&String> = defaults.iter().map(|s| &s.id).collect();
+        assert_eq!(ids.len(), defaults.len());
+    }
+
+    #[test]
+    fn test_default_snippets_ids_start_with_default() {
+        let defaults = get_default_snippets();
+        assert!(defaults.iter().all(|s| s.id.starts_with("default-")));
+    }
+
+    #[test]
+    fn test_snippet_serialization() {
+        let snippet = create_test_snippet("test-1", "Test Snippet", "Testing", false);
+        let json = serde_json::to_string(&snippet).expect("Failed to serialize");
+        let parsed: Snippet = serde_json::from_str(&json).expect("Failed to deserialize");
+
+        assert_eq!(parsed.id, snippet.id);
+        assert_eq!(parsed.name, snippet.name);
+        assert_eq!(parsed.content, snippet.content);
+        assert_eq!(parsed.category, snippet.category);
+        assert_eq!(parsed.is_default, snippet.is_default);
+    }
+
+    #[test]
+    fn test_snippet_clone() {
+        let original = create_test_snippet("clone-test", "Clone Test", "Category", true);
+        let cloned = original.clone();
+
+        assert_eq!(original.id, cloned.id);
+        assert_eq!(original.name, cloned.name);
+        assert_eq!(original.is_default, cloned.is_default);
+    }
+
+    #[test]
+    #[allow(clippy::useless_vec)]
+    fn test_snippet_sorting_by_category_then_name() {
+        let mut snippets = vec![
+            create_test_snippet("s1", "Zebra", "B-Category", false),
+            create_test_snippet("s2", "Apple", "A-Category", false),
+            create_test_snippet("s3", "Banana", "B-Category", false),
+            create_test_snippet("s4", "Alpha", "A-Category", false),
+        ];
+
+        // Sort by category, then by name (mimics list_snippets behavior)
+        snippets.sort_by(|a, b| {
+            let cat_cmp = a.category.cmp(&b.category);
+            if cat_cmp == std::cmp::Ordering::Equal {
+                a.name.cmp(&b.name)
+            } else {
+                cat_cmp
+            }
+        });
+
+        // A-Category should come first
+        assert_eq!(snippets[0].category, "A-Category");
+        assert_eq!(snippets[1].category, "A-Category");
+        assert_eq!(snippets[2].category, "B-Category");
+        assert_eq!(snippets[3].category, "B-Category");
+
+        // Within categories, alphabetically by name
+        assert_eq!(snippets[0].name, "Alpha");
+        assert_eq!(snippets[1].name, "Apple");
+        assert_eq!(snippets[2].name, "Banana");
+        assert_eq!(snippets[3].name, "Zebra");
+    }
+
+    #[test]
+    fn test_known_default_snippets() {
+        let defaults = get_default_snippets();
+        let ids: Vec<&str> = defaults.iter().map(|s| s.id.as_str()).collect();
+
+        assert!(ids.contains(&"default-explain-code"));
+        assert!(ids.contains(&"default-fix-error"));
+        assert!(ids.contains(&"default-write-tests"));
+        assert!(ids.contains(&"default-refactor"));
+        assert!(ids.contains(&"default-optimize"));
+        assert!(ids.contains(&"default-review-pr"));
+        assert!(ids.contains(&"default-add-comments"));
+        assert!(ids.contains(&"default-security-review"));
+    }
+
+    #[test]
+    fn test_default_snippet_categories() {
+        let defaults = get_default_snippets();
+        let categories: HashSet<&String> = defaults.iter().map(|s| &s.category).collect();
+
+        assert!(categories.contains(&"Code Review".to_string()));
+        assert!(categories.contains(&"Debugging".to_string()));
+        assert!(categories.contains(&"Testing".to_string()));
+        assert!(categories.contains(&"Performance".to_string()));
+        assert!(categories.contains(&"Documentation".to_string()));
+        assert!(categories.contains(&"Security".to_string()));
+    }
+
+    #[test]
+    fn test_snippet_content_not_empty() {
+        let defaults = get_default_snippets();
+        for snippet in defaults {
+            assert!(
+                snippet.content.len() > 10,
+                "Content should be meaningful: {}",
+                snippet.name
+            );
+        }
+    }
+
+    #[test]
+    fn test_snippet_timestamps() {
+        let snippet = create_test_snippet("time-test", "Time Test", "Cat", false);
+        assert!(snippet.created_at <= snippet.updated_at);
+    }
+
+    #[test]
+    fn test_default_snippets_have_same_timestamps() {
+        let defaults = get_default_snippets();
+        // All defaults are created at the same instant
+        let first_created = defaults[0].created_at;
+        let first_updated = defaults[0].updated_at;
+
+        for snippet in &defaults {
+            assert_eq!(snippet.created_at, first_created);
+            assert_eq!(snippet.updated_at, first_updated);
+        }
+    }
+
+    #[test]
+    fn test_snippet_retain_non_default() {
+        let mut snippets = vec![
+            create_test_snippet("default-1", "Default 1", "Cat", true),
+            create_test_snippet("custom-1", "Custom 1", "Cat", false),
+            create_test_snippet("default-2", "Default 2", "Cat", true),
+            create_test_snippet("custom-2", "Custom 2", "Cat", false),
+        ];
+
+        // Mimics reset_default_snippets behavior (retain non-defaults)
+        snippets.retain(|s| !s.is_default);
+
+        assert_eq!(snippets.len(), 2);
+        assert!(snippets.iter().all(|s| !s.is_default));
+    }
+
+    #[test]
+    #[allow(clippy::useless_vec)]
+    fn test_snippet_find_by_id() {
+        let snippets = vec![
+            create_test_snippet("snippet-1", "First", "Cat", false),
+            create_test_snippet("snippet-2", "Second", "Cat", false),
+            create_test_snippet("snippet-3", "Third", "Cat", false),
+        ];
+
+        let found = snippets.iter().find(|s| s.id == "snippet-2");
+        assert!(found.is_some());
+        assert_eq!(found.unwrap().name, "Second");
+
+        let not_found = snippets.iter().find(|s| s.id == "snippet-999");
+        assert!(not_found.is_none());
+    }
+
+    #[test]
+    #[allow(clippy::useless_vec)]
+    fn test_extract_categories_sorted_and_deduped() {
+        let snippets = vec![
+            create_test_snippet("s1", "S1", "Zebra", false),
+            create_test_snippet("s2", "S2", "Alpha", false),
+            create_test_snippet("s3", "S3", "Beta", false),
+            create_test_snippet("s4", "S4", "Alpha", false), // Duplicate
+        ];
+
+        let mut categories: Vec<String> = snippets.iter().map(|s| s.category.clone()).collect();
+        categories.sort();
+        categories.dedup();
+
+        assert_eq!(categories.len(), 3);
+        assert_eq!(categories[0], "Alpha");
+        assert_eq!(categories[1], "Beta");
+        assert_eq!(categories[2], "Zebra");
+    }
+
+    #[test]
+    fn test_snippet_category_code_review_count() {
+        let defaults = get_default_snippets();
+        let code_review_count = defaults
+            .iter()
+            .filter(|s| s.category == "Code Review")
+            .count();
+
+        // There should be multiple code review snippets
+        assert!(code_review_count >= 2);
+    }
 }

src-tauri/src/stats.rs

@@ -369,6 +369,36 @@ mod tests {
         assert!((cost - 0.165).abs() < 0.0001);
     }
 
+    #[test]
+    fn test_cost_calculation_opus_45() {
+        let cost = calculate_cost(1000, 2000, "claude-opus-4-5-20251101");
+        // Same pricing as Opus 4
+        assert!((cost - 0.165).abs() < 0.0001);
+    }
+
+    #[test]
+    fn test_cost_calculation_haiku() {
+        let cost = calculate_cost(1000, 2000, "claude-3-5-haiku-20241022");
+        // 1000 input * $1/M = $0.001
+        // 2000 output * $5/M = $0.010
+        // Total = $0.011
+        assert!((cost - 0.011).abs() < 0.0001);
+    }
+
+    #[test]
+    fn test_cost_calculation_unknown_defaults_to_sonnet() {
+        let cost = calculate_cost(1000, 2000, "some-unknown-model");
+        // Should default to Sonnet pricing
+        assert!((cost - 0.033).abs() < 0.0001);
+    }
+
+    #[test]
+    fn test_cost_calculation_legacy_sonnet() {
+        let cost = calculate_cost(1000, 2000, "claude-3-5-sonnet-20241022");
+        // Same as Sonnet 4 pricing
+        assert!((cost - 0.033).abs() < 0.0001);
+    }
+
     #[test]
     fn test_usage_stats_accumulation() {
         let mut stats = UsageStats::new();
@@ -381,6 +411,28 @@ mod tests {
         assert!((stats.total_cost_usd - 0.033).abs() < 0.0001);
     }
 
+    #[test]
+    fn test_usage_stats_multiple_accumulations() {
+        let mut stats = UsageStats::new();
+        stats.add_usage(1000, 1000, "claude-sonnet-4-20250514");
+        stats.add_usage(500, 500, "claude-sonnet-4-20250514");
+
+        assert_eq!(stats.total_input_tokens, 1500);
+        assert_eq!(stats.total_output_tokens, 1500);
+        assert_eq!(stats.session_input_tokens, 1500);
+        assert_eq!(stats.session_output_tokens, 1500);
+    }
+
+    #[test]
+    fn test_usage_stats_model_updated() {
+        let mut stats = UsageStats::new();
+        stats.add_usage(1000, 1000, "claude-sonnet-4-20250514");
+        assert_eq!(stats.model, Some("claude-sonnet-4-20250514".to_string()));
+
+        stats.add_usage(500, 500, "claude-opus-4-20250514");
+        assert_eq!(stats.model, Some("claude-opus-4-20250514".to_string()));
+    }
+
     #[test]
     fn test_session_reset() {
         let mut stats = UsageStats::new();
@@ -394,4 +446,230 @@ mod tests {
         assert_eq!(stats.session_cost_usd, 0.0);
         assert!(stats.total_cost_usd > 0.0);
     }
+
+    #[test]
+    fn test_session_reset_clears_session_stats() {
+        let mut stats = UsageStats::new();
+        stats.increment_messages();
+        stats.increment_messages();
+        stats.increment_code_blocks();
+        stats.increment_files_edited();
+        stats.increment_files_created();
+        stats.increment_tool_usage("Read");
+
+        stats.reset_session();
+
+        assert_eq!(stats.session_messages_exchanged, 0);
+        assert_eq!(stats.session_code_blocks_generated, 0);
+        assert_eq!(stats.session_files_edited, 0);
+        assert_eq!(stats.session_files_created, 0);
+        assert!(stats.session_tools_usage.is_empty());
+    }
+
+    #[test]
+    fn test_increment_messages() {
+        let mut stats = UsageStats::new();
+        stats.increment_messages();
+        stats.increment_messages();
+        stats.increment_messages();
+
+        assert_eq!(stats.messages_exchanged, 3);
+        assert_eq!(stats.session_messages_exchanged, 3);
+    }
+
+    #[test]
+    fn test_increment_code_blocks() {
+        let mut stats = UsageStats::new();
+        stats.increment_code_blocks();
+        stats.increment_code_blocks();
+
+        assert_eq!(stats.code_blocks_generated, 2);
+        assert_eq!(stats.session_code_blocks_generated, 2);
+    }
+
+    #[test]
+    fn test_increment_files_edited() {
+        let mut stats = UsageStats::new();
+        stats.increment_files_edited();
+
+        assert_eq!(stats.files_edited, 1);
+        assert_eq!(stats.session_files_edited, 1);
+    }
+
+    #[test]
+    fn test_increment_files_created() {
+        let mut stats = UsageStats::new();
+        stats.increment_files_created();
+
+        assert_eq!(stats.files_created, 1);
+        assert_eq!(stats.session_files_created, 1);
+    }
+
+    #[test]
+    fn test_increment_tool_usage() {
+        let mut stats = UsageStats::new();
+        stats.increment_tool_usage("Read");
+        stats.increment_tool_usage("Read");
+        stats.increment_tool_usage("Write");
+
+        assert_eq!(stats.tools_usage.get("Read"), Some(&2));
+        assert_eq!(stats.tools_usage.get("Write"), Some(&1));
+        assert_eq!(stats.session_tools_usage.get("Read"), Some(&2));
+        assert_eq!(stats.session_tools_usage.get("Write"), Some(&1));
+    }
+
+    #[test]
+    fn test_session_duration_tracking() {
+        let mut stats = UsageStats::new();
+        stats.session_start = Some(Instant::now());
+
+        // Verify duration is returned (u64 is always non-negative)
+        let _duration = stats.get_session_duration();
+    }
+
+    #[test]
+    fn test_session_duration_without_start() {
+        let mut stats = UsageStats::new();
+        stats.session_start = None;
+        stats.session_duration_seconds = 100;
+
+        // Should return the stored value when no start time
+        let duration = stats.get_session_duration();
+        assert_eq!(duration, 100);
+    }
+
+    #[test]
+    fn test_is_consecutive_day_true() {
+        assert!(is_consecutive_day("2024-01-15", "2024-01-16"));
+        assert!(is_consecutive_day("2024-12-31", "2025-01-01"));
+    }
+
+    #[test]
+    fn test_is_consecutive_day_false() {
+        assert!(!is_consecutive_day("2024-01-15", "2024-01-15")); // Same day
+        assert!(!is_consecutive_day("2024-01-15", "2024-01-17")); // Gap
+        assert!(!is_consecutive_day("2024-01-15", "2024-01-14")); // Backwards
+    }
+
+    #[test]
+    fn test_is_consecutive_day_invalid_dates() {
+        assert!(!is_consecutive_day("invalid", "2024-01-01"));
+        assert!(!is_consecutive_day("2024-01-01", "invalid"));
+        assert!(!is_consecutive_day("invalid", "also-invalid"));
+    }
+
+    #[test]
+    fn test_persisted_stats_from_usage_stats() {
+        let mut stats = UsageStats::new();
+        stats.total_input_tokens = 5000;
+        stats.total_output_tokens = 10000;
+        stats.total_cost_usd = 1.23;
+        stats.messages_exchanged = 50;
+        stats.sessions_started = 5;
+        stats.consecutive_days = 3;
+
+        let persisted = PersistedStats::from(&stats);
+
+        assert_eq!(persisted.total_input_tokens, 5000);
+        assert_eq!(persisted.total_output_tokens, 10000);
+        assert_eq!(persisted.total_cost_usd, 1.23);
+        assert_eq!(persisted.messages_exchanged, 50);
+        assert_eq!(persisted.sessions_started, 5);
+        assert_eq!(persisted.consecutive_days, 3);
+    }
+
+    #[test]
+    fn test_apply_persisted_stats() {
+        let persisted = PersistedStats {
+            total_input_tokens: 10000,
+            total_output_tokens: 20000,
+            total_cost_usd: 5.50,
+            messages_exchanged: 100,
+            code_blocks_generated: 25,
+            files_edited: 10,
+            files_created: 5,
+            tools_usage: {
+                let mut map = HashMap::new();
+                map.insert("Read".to_string(), 50);
+                map
+            },
+            sessions_started: 10,
+            consecutive_days: 7,
+            total_days_used: 14,
+            morning_sessions: 3,
+            night_sessions: 2,
+            last_session_date: Some("2024-06-15".to_string()),
+        };
+
+        let mut stats = UsageStats::new();
+        stats.apply_persisted(persisted);
+
+        assert_eq!(stats.total_input_tokens, 10000);
+        assert_eq!(stats.total_output_tokens, 20000);
+        assert_eq!(stats.total_cost_usd, 5.50);
+        assert_eq!(stats.messages_exchanged, 100);
+        assert_eq!(stats.tools_usage.get("Read"), Some(&50));
+        assert_eq!(stats.consecutive_days, 7);
+        assert_eq!(stats.morning_sessions, 3);
+        assert_eq!(stats.last_session_date, Some("2024-06-15".to_string()));
+    }
+
+    #[test]
+    fn test_usage_stats_default() {
+        let stats = UsageStats::default();
+
+        assert_eq!(stats.total_input_tokens, 0);
+        assert_eq!(stats.total_output_tokens, 0);
+        assert_eq!(stats.total_cost_usd, 0.0);
+        assert!(stats.model.is_none());
+    }
+
+    #[test]
+    fn test_persisted_stats_default() {
+        let persisted = PersistedStats::default();
+
+        assert_eq!(persisted.total_input_tokens, 0);
+        assert!(persisted.last_session_date.is_none());
+    }
+
+    #[test]
+    fn test_usage_stats_serialization() {
+        let mut stats = UsageStats::new();
+        stats.add_usage(1000, 2000, "claude-sonnet-4-20250514");
+        stats.increment_messages();
+
+        // UsageStats should be serializable (for events)
+        let json = serde_json::to_string(&stats).expect("Failed to serialize");
+        assert!(json.contains("total_input_tokens"));
+        assert!(json.contains("1000"));
+    }
+
+    #[test]
+    fn test_persisted_stats_serialization() {
+        let persisted = PersistedStats {
+            total_input_tokens: 1234,
+            total_output_tokens: 5678,
+            total_cost_usd: 0.99,
+            ..Default::default()
+        };
+
+        let json = serde_json::to_string(&persisted).expect("Failed to serialize");
+        let parsed: PersistedStats = serde_json::from_str(&json).expect("Failed to deserialize");
+
+        assert_eq!(parsed.total_input_tokens, 1234);
+        assert_eq!(parsed.total_output_tokens, 5678);
+        assert!((parsed.total_cost_usd - 0.99).abs() < 0.0001);
+    }
+
+    #[test]
+    fn test_stats_update_event_serialization() {
+        let mut stats = UsageStats::new();
+        stats.add_usage(100, 200, "claude-sonnet-4-20250514");
+
+        let event = StatsUpdateEvent { stats };
+        let json = serde_json::to_string(&event).expect("Failed to serialize");
+
+        assert!(json.contains("stats"));
+        assert!(json.contains("total_input_tokens"));
+    }
 }

src-tauri/src/temp_manager.rs

@@ -137,3 +137,290 @@ pub type SharedTempFileManager = Arc<Mutex<TempFileManager>>;
 pub fn create_shared_temp_manager() -> Result<SharedTempFileManager, String> {
     Ok(Arc::new(Mutex::new(TempFileManager::new()?)))
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::fs;
+    use tempfile::TempDir;
+
+    // Helper to create a TempFileManager with a custom base directory for testing
+    fn create_test_manager(base_dir: PathBuf) -> TempFileManager {
+        if !base_dir.exists() {
+            fs::create_dir_all(&base_dir).expect("Failed to create test temp dir");
+        }
+        TempFileManager {
+            base_dir,
+            files: HashMap::new(),
+        }
+    }
+
+    #[test]
+    fn test_new_creates_base_directory() {
+        let manager = TempFileManager::new().expect("Failed to create TempFileManager");
+        assert!(manager.base_dir.exists());
+    }
+
+    #[test]
+    fn test_get_base_dir_returns_correct_path() {
+        let temp_dir = TempDir::new().expect("Failed to create temp dir");
+        let base_path = temp_dir.path().join("hikari-test");
+        let manager = create_test_manager(base_path.clone());
+
+        assert_eq!(manager.get_base_dir(), base_path.as_path());
+    }
+
+    #[test]
+    fn test_save_file_creates_file_with_content() {
+        let temp_dir = TempDir::new().expect("Failed to create temp dir");
+        let base_path = temp_dir.path().join("hikari-test");
+        let mut manager = create_test_manager(base_path);
+
+        let data = b"Hello, world!";
+        let result = manager.save_file("conv-1", data, Some("test.txt"));
+
+        assert!(result.is_ok());
+        let file_path = result.unwrap();
+        assert!(file_path.exists());
+
+        let content = fs::read(&file_path).expect("Failed to read file");
+        assert_eq!(content, data);
+    }
+
+    #[test]
+    fn test_save_file_uses_correct_extension() {
+        let temp_dir = TempDir::new().expect("Failed to create temp dir");
+        let base_path = temp_dir.path().join("hikari-test");
+        let mut manager = create_test_manager(base_path);
+
+        let data = b"test data";
+        let result = manager.save_file("conv-1", data, Some("document.pdf"));
+
+        assert!(result.is_ok());
+        let file_path = result.unwrap();
+        assert_eq!(file_path.extension().unwrap(), "pdf");
+    }
+
+    #[test]
+    fn test_save_file_uses_bin_extension_when_no_filename() {
+        let temp_dir = TempDir::new().expect("Failed to create temp dir");
+        let base_path = temp_dir.path().join("hikari-test");
+        let mut manager = create_test_manager(base_path);
+
+        let data = b"binary data";
+        let result = manager.save_file("conv-1", data, None);
+
+        assert!(result.is_ok());
+        let file_path = result.unwrap();
+        assert_eq!(file_path.extension().unwrap(), "bin");
+    }
+
+    #[test]
+    fn test_register_file_tracks_file_path() {
+        let temp_dir = TempDir::new().expect("Failed to create temp dir");
+        let base_path = temp_dir.path().join("hikari-test");
+        let mut manager = create_test_manager(base_path);
+
+        let file_path = PathBuf::from("/some/path/file.txt");
+        manager.register_file("conv-1", file_path.clone());
+
+        let files = manager.get_files_for_conversation("conv-1");
+        assert_eq!(files.len(), 1);
+        assert_eq!(files[0], file_path);
+    }
+
+    #[test]
+    fn test_get_files_for_conversation_returns_empty_for_unknown() {
+        let temp_dir = TempDir::new().expect("Failed to create temp dir");
+        let base_path = temp_dir.path().join("hikari-test");
+        let manager = create_test_manager(base_path);
+
+        let files = manager.get_files_for_conversation("unknown-conv");
+        assert!(files.is_empty());
+    }
+
+    #[test]
+    fn test_get_files_for_conversation_returns_all_files() {
+        let temp_dir = TempDir::new().expect("Failed to create temp dir");
+        let base_path = temp_dir.path().join("hikari-test");
+        let mut manager = create_test_manager(base_path);
+
+        let data = b"test";
+        manager.save_file("conv-1", data, Some("file1.txt")).unwrap();
+        manager.save_file("conv-1", data, Some("file2.txt")).unwrap();
+        manager.save_file("conv-2", data, Some("file3.txt")).unwrap();
+
+        let files_conv1 = manager.get_files_for_conversation("conv-1");
+        let files_conv2 = manager.get_files_for_conversation("conv-2");
+
+        assert_eq!(files_conv1.len(), 2);
+        assert_eq!(files_conv2.len(), 1);
+    }
+
+    #[test]
+    fn test_cleanup_conversation_removes_files() {
+        let temp_dir = TempDir::new().expect("Failed to create temp dir");
+        let base_path = temp_dir.path().join("hikari-test");
+        let mut manager = create_test_manager(base_path);
+
+        let data = b"test";
+        let file_path = manager.save_file("conv-1", data, Some("test.txt")).unwrap();
+        assert!(file_path.exists());
+
+        let result = manager.cleanup_conversation("conv-1");
+        assert!(result.is_ok());
+        assert!(!file_path.exists());
+        assert!(manager.get_files_for_conversation("conv-1").is_empty());
+    }
+
+    #[test]
+    fn test_cleanup_conversation_handles_missing_files() {
+        let temp_dir = TempDir::new().expect("Failed to create temp dir");
+        let base_path = temp_dir.path().join("hikari-test");
+        let mut manager = create_test_manager(base_path);
+
+        // Register a file that doesn't exist
+        manager.register_file("conv-1", PathBuf::from("/nonexistent/file.txt"));
+
+        // Should not error, just skip missing files
+        let result = manager.cleanup_conversation("conv-1");
+        assert!(result.is_ok());
+    }
+
+    #[test]
+    fn test_cleanup_conversation_for_unknown_returns_ok() {
+        let temp_dir = TempDir::new().expect("Failed to create temp dir");
+        let base_path = temp_dir.path().join("hikari-test");
+        let mut manager = create_test_manager(base_path);
+
+        let result = manager.cleanup_conversation("unknown-conv");
+        assert!(result.is_ok());
+    }
+
+    #[test]
+    fn test_cleanup_all_removes_all_files() {
+        let temp_dir = TempDir::new().expect("Failed to create temp dir");
+        let base_path = temp_dir.path().join("hikari-test");
+        let mut manager = create_test_manager(base_path);
+
+        let data = b"test";
+        let file1 = manager.save_file("conv-1", data, Some("f1.txt")).unwrap();
+        let file2 = manager.save_file("conv-2", data, Some("f2.txt")).unwrap();
+
+        assert!(file1.exists());
+        assert!(file2.exists());
+
+        let result = manager.cleanup_all();
+        assert!(result.is_ok());
+
+        assert!(!file1.exists());
+        assert!(!file2.exists());
+        assert!(manager.files.is_empty());
+    }
+
+    #[test]
+    fn test_cleanup_orphaned_files_removes_untracked() {
+        let temp_dir = TempDir::new().expect("Failed to create temp dir");
+        let base_path = temp_dir.path().join("hikari-test");
+        let mut manager = create_test_manager(base_path.clone());
+
+        // Create a tracked file
+        let data = b"tracked";
+        let tracked_path = manager.save_file("conv-1", data, Some("tracked.txt")).unwrap();
+
+        // Create an untracked (orphaned) file directly in the temp directory
+        let orphan_path = base_path.join("orphan.txt");
+        fs::write(&orphan_path, b"orphan").expect("Failed to create orphan file");
+
+        assert!(tracked_path.exists());
+        assert!(orphan_path.exists());
+
+        let result = manager.cleanup_orphaned_files();
+        assert!(result.is_ok());
+        assert_eq!(result.unwrap(), 1); // One orphan removed
+
+        assert!(tracked_path.exists()); // Tracked file still exists
+        assert!(!orphan_path.exists()); // Orphan removed
+    }
+
+    #[test]
+    fn test_cleanup_orphaned_returns_zero_when_none() {
+        let temp_dir = TempDir::new().expect("Failed to create temp dir");
+        let base_path = temp_dir.path().join("hikari-test");
+        let mut manager = create_test_manager(base_path);
+
+        let data = b"test";
+        manager.save_file("conv-1", data, Some("test.txt")).unwrap();
+
+        let result = manager.cleanup_orphaned_files();
+        assert!(result.is_ok());
+        assert_eq!(result.unwrap(), 0);
+    }
+
+    #[test]
+    fn test_cleanup_orphaned_returns_zero_when_dir_missing() {
+        let mut manager = TempFileManager {
+            base_dir: PathBuf::from("/nonexistent/dir"),
+            files: HashMap::new(),
+        };
+
+        let result = manager.cleanup_orphaned_files();
+        assert!(result.is_ok());
+        assert_eq!(result.unwrap(), 0);
+    }
+
+    #[test]
+    fn test_default_creates_manager() {
+        // Default should work as long as we can create temp directories
+        let manager = TempFileManager::default();
+        assert!(manager.base_dir.exists());
+    }
+
+    #[test]
+    fn test_create_shared_temp_manager() {
+        let result = create_shared_temp_manager();
+        assert!(result.is_ok());
+
+        let shared = result.unwrap();
+        let manager = shared.lock();
+        assert!(manager.base_dir.exists());
+    }
+
+    #[test]
+    fn test_multiple_files_same_conversation() {
+        let temp_dir = TempDir::new().expect("Failed to create temp dir");
+        let base_path = temp_dir.path().join("hikari-test");
+        let mut manager = create_test_manager(base_path);
+
+        // Save multiple files to same conversation
+        for i in 0..5 {
+            let data = format!("content {}", i);
+            manager
+                .save_file("conv-1", data.as_bytes(), Some(&format!("file{}.txt", i)))
+                .unwrap();
+        }
+
+        let files = manager.get_files_for_conversation("conv-1");
+        assert_eq!(files.len(), 5);
+
+        // Each file should have unique content
+        for (i, file_path) in files.iter().enumerate() {
+            let content = fs::read_to_string(file_path).expect("Failed to read");
+            assert_eq!(content, format!("content {}", i));
+        }
+    }
+
+    #[test]
+    fn test_file_paths_contain_conversation_id() {
+        let temp_dir = TempDir::new().expect("Failed to create temp dir");
+        let base_path = temp_dir.path().join("hikari-test");
+        let mut manager = create_test_manager(base_path);
+
+        let file_path = manager
+            .save_file("my-conversation-id", b"test", Some("test.txt"))
+            .unwrap();
+
+        let filename = file_path.file_name().unwrap().to_str().unwrap();
+        assert!(filename.starts_with("my-conversation-id_"));
+    }
+}