Description

This PR lays the groundwork for Multi-Workspace Folder Support in Cline, addressing the need for enterprise users and modern development workflows to work across multiple repositories simultaneously.

Problem Solved

Currently, Cline is limited to a single root directory (cwd), which prevents users from:

• Working on microservices architectures with multiple repositories
• Coordinating changes across frontend/backend/shared library projects
• Managing monorepo sub-projects effectively

What This PR Introduces

Phase 0 Implementation - Infrastructure and Migration Preparation:

1. WorkspaceRootManager Class (src/core/workspace/WorkspaceRootManager.ts)

   • Central manager for multi-workspace operations
   • Handles workspace root resolution and path mapping
   • Provides backward compatibility through fromLegacyCwd() method
   • Supports Git/Mercurial VCS detection

2. WorkspaceResolver Tracer Functions (src/core/workspace/WorkspaceResolver.ts)

   • Non-breaking tracer functions to track single-root assumptions
   • Already deployed across 52+ files in the codebase
   • Provides telemetry for migration planning

Technical Approach

The implementation follows a phased migration strategy:

• Phase 0 (This PR): Infrastructure setup and migration tracking
• Phase 1: Core state management migration (cwd → workspaceRoots[])
• Phase 2: RPC & Task integration
• Phase 3: Tool migration (18 tool handlers)
• Phase 4: Distributed checkpoint system
• Phase 5: Testing & validation

This approach ensures backward compatibility while gradually introducing multi-workspace capabilities.

Test Procedure

Testing Approach

1. Backward Compatibility Testing

   • Verified existing single-root tasks continue to work unchanged
   • Tested WorkspaceRootManager.fromLegacyCwd() conversion
   • Ensured tracer functions don't break existing path operations

2. WorkspaceRootManager Testing

   • Path resolution with nested workspaces
   • VCS detection (Git/Mercurial/None)
   • Serialization/deserialization for task persistence
   • Primary workspace management

3. Integration Points Verified

   • All 52+ files with tracer functions continue to work
   • No performance degradation in path operations
   • Module exports properly configured

What Could Break & Verification

• Path Resolution: Tested with absolute/relative paths, symlinks
• Task Initialization: Verified legacy task loading still works
• Tool Handlers: Confirmed tracer functions don't affect tool execution
• Performance: Measured overhead of tracer functions (<1ms average)

Confidence Level

This PR is ready for merge because:

• It's non-breaking (Phase 0 is purely additive)
• All existing functionality remains intact
• Comprehensive testing of backward compatibility
• Clear migration path documented

Type of Change

• 🐛 Bug fix (non-breaking change which fixes an issue)
• ✨ New feature (non-breaking change which adds functionality)
• 💥 Breaking change (fix or feature that would cause existing functionality to not work as expected)
• ♻️ Refactor Changes
• 💅 Cosmetic Changes
• 📚 Documentation update
• 🏃 Workflow Changes

Pre-flight Checklist

• Changes are limited to a single feature, bugfix or chore (split larger changes into separate PRs)
• Tests are passing (npm test) and code is formatted and linted (npm run format && npm run lint)
• I have created a changeset using npm run changeset (required for user-facing changes)
• I have reviewed contributor guidelines

Screenshots

Migration Report Output Example

# Multi-Workspace Migration Report

## Executive Summary
- Total Components Tracked: 52 files
- Total Path Operations: 300+
- Performance Impact: <1ms average overhead

## Component Analysis
### Tool Handlers (18 files)
- High Usage: ExecuteCommandToolHandler (45 calls)
- Medium Usage: ReadFileToolHandler (32 calls)
...

## Risk Assessment
⚠️ High-Risk Components:
- CheckpointTracker: Complex refactor needed
- Terminal Management: Command context required

WorkspaceRootManager API

// Backward compatibility
const manager = await WorkspaceRootManager.fromLegacyCwd('/single/root')

// Multi-workspace
const manager = new WorkspaceRootManager([
  { path: '/frontend', name: 'frontend', vcs: VcsType.Git },
  { path: '/backend', name: 'backend', vcs: VcsType.Git }
], 0) // primary index

// Path resolution
const root = manager.resolvePathToRoot('/frontend/src/App.tsx')
// Returns: { path: '/frontend', name: 'frontend', ... }

Additional Notes

Important Notes for Reviewers:

1. This is Phase 0 of a larger feature - This PR sets up the infrastructure without changing existing behavior. The actual multi-workspace functionality will come in subsequent PRs (Phases 1-5).

2. Performance Considerations - The tracer functions add minimal overhead (<1ms) and can be disabled via environment variable if needed.

3. Migration Strategy - The phased approach allows for gradual rollout with ability to pause/rollback at any phase if issues arise.

4. Enterprise Focus - This feature primarily benefits enterprise users with multi-repository workflows, but maintains full backward compatibility for single-root users.

5. Next Steps After Merge:

   • Phase 1 PR: Core state management migration
   • Phase 2 PR: RPC & task integration
   • Phase 3 PR: Tool migration
   • Phase 4 PR: Checkpoint distribution
   • Phase 5 PR: Final testing & documentation

Questions for Maintainers:

• Should we add feature flag for gradual rollout?
• Any concerns about the WorkspaceRoot data structure?
• Preferences on checkpoint system architecture for multi-repo?

Related Documentation:

• Implementation Breakdown
• Migration Report Guide