rust-patterns

name	rust-patterns
description	Rust-specific coding patterns and conventions used in the Grove codebase. Loaded for Builder and Reviewer agents working on Rust code.
applies_to	["builder","reviewer"]

Grove Rust Patterns

Error Handling

• Use GroveResult<T> (alias for Result<T, GroveError>) everywhere
• Use ? operator for propagation — no .unwrap() in production code
• Map external errors: external_call().map_err(|e| GroveError::External(e.to_string()))?
• Use GroveError::NotFound for missing resources, GroveError::Config for config issues

Database (rusqlite)

• All DB operations through rusqlite::Connection
• Use conn.execute() for writes, conn.query_row() for single reads
• Use conn.prepare() + stmt.query_map() for multi-row reads
• Always use parameterized queries: [&run_id], never string interpolation
• Migrations in crates/grove-core/src/db/migrations/ — numbered sequentially

Serialization

• #[derive(Serialize, Deserialize)] on all IPC types
• #[serde(rename_all = "snake_case")] for enums
• #[serde(default)] for optional fields that may be missing in older data

File I/O

• Use std::fs for sync file operations
• Always create parent directories: fs::create_dir_all(parent)?
• Use Path and PathBuf — never string concatenation for paths

Tauri Commands

• All commands are #[tauri::command] async functions
• Use spawn_blocking for sync operations (DB, git, file I/O)
• Return Result<T, String> where T: Serialize
• Error conversion: .map_err(|e| e.to_string())?

Testing

• #[cfg(test)] mod tests at bottom of each module
• Use tempfile::tempdir() for filesystem tests
• Use in-memory SQLite: Connection::open_in_memory()
• Test names: snake_case_describing_behavior