[ENHANCEMENT]

[purujawa06-bot]

Problem (one or two sentences)

Why are all the files in node_modules going into 'database indexing'?

Context (who is affected and when)

Indexing performance

Desired behavior (conceptual, not technical)

Null

Constraints / preferences (optional)

No response

Request checklist

• I've searched existing Issues and Discussions for duplicates
• This describes a specific problem with clear context and impact

Roo Code Task Links (optional)

No response

Acceptance criteria (optional)

No response

Proposed approach (optional)

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Trade-offs / risks (optional)

No response

[roomote-v0]

I've analyzed this issue and here's my proposed implementation plan:

Analysis

The code indexing system has two paths for discovering files:

1. Initial scan (src/services/code-index/processors/scanner.ts): Uses listFiles() with ripgrep, which respects .gitignore and explicitly adds exclusion globs for DIRS_TO_IGNORE (which includes node_modules). After listing, it also double-checks with isPathInIgnoredDirectory(). This path properly excludes node_modules.

2. File watcher (src/services/code-index/processors/file-watcher.ts): Uses a VS Code FileSystemWatcher with a glob pattern **/*{extensions} that does not exclude node_modules. The event handlers (handleFileCreated, handleFileChanged, handleFileDeleted) accumulate events into accumulatedEvents without any filtering. Filtering only happens later in processFile() when events are batch-processed.

This means that when npm install runs (or similar package manager operations), thousands of file events from node_modules are accumulated, debounced, and then processed one by one -- only to be filtered out in processFile(). This causes unnecessary overhead and likely triggers visible indexing activity in the UI, even though the files ultimately get skipped.

Proposed Fix

Add early filtering in the file watcher event handlers to skip files in ignored directories before they are accumulated:

1. Add a private helper method shouldIgnoreFile(uri: vscode.Uri): boolean to FileWatcher that checks isPathInIgnoredDirectory() on the relative path.

2. Guard the three event handlers (handleFileCreated, handleFileChanged, handleFileDeleted) with this check so that node_modules events are discarded immediately and never reach accumulatedEvents.

3. Add tests to verify that file watcher events for paths inside node_modules (and other ignored directories) are not accumulated or processed.

This approach is minimal and surgical -- it prevents the unnecessary accumulation and processing at the earliest possible point, without changing any other behavior.

Please mention @roomote in a comment saying that you approve this plan, and I'll proceed with the implementation.