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Validate before expensive operations

Perform lightweight validation checks before executing expensive operations to avoid unnecessary resource consumption. This is especially important in hot paths or frequently called functions.

raw .md Performance Optimization TypeScript

Perform lightweight validation checks before executing expensive operations to avoid unnecessary resource consumption. This is especially important in hot paths or frequently called functions.

Key practices:

Use file system operations instead of process spawning
Check file sizes before reading entire files
Filter collections before heavy processing
Use specific API methods instead of broad queries

Example - Before:

async function getWorktrees(): Promise<Worktree[]> {
    // Spawns process on hot path
    const result = await spawn('git', ['worktree', 'list']);
    return parseWorktrees(result);
}

After:

async function getWorktrees(): Promise<Worktree[]> {
    // Use fs operations first
    const hasWorktrees = await fs.exists('.git/worktrees');
    if (!hasWorktrees) {
        return [];
    }
    // Only spawn process if needed
    const result = await spawn('git', ['worktree', 'list']);
    return parseWorktrees(result);
}