manual_slop/conductor/tracks/tier4_auto_patching_20260306/spec.md

Track Specification: Advanced Tier 4 QA Auto-Patching (tier4_auto_patching_20260306)

Overview

Elevate Tier 4 from log summarizer to auto-patcher. When verification tests fail, Tier 4 generates a unified diff patch. GUI displays side-by-side diff; user clicks Apply Patch to resume pipeline.

Current State Audit

Already Implemented (DO NOT re-implement)

Tier 4 Analysis (ai_client.py)

• run_tier4_analysis(stderr: str) -> str: Analyzes error, returns summary
• Prompt: Uses mma_prompts.PROMPTS["tier4_error_triage"]
• Output: Text analysis, no code generation

Error Interception (shell_runner.py)

• run_powershell(): Accepts qa_callback parameter
• On failure: Calls qa_callback(stderr) and appends to output
• Integrated: ai_client._run_script() passes qa_callback

MCP Tools (mcp_client.py)

• set_file_slice(): Replace line range in file
• py_update_definition(): Replace class/function via AST
• edit_file(): String replacement in file
• No diff generation or patch application

Gaps to Fill (This Track's Scope)

• Tier 4 doesn't generate patches
• No diff visualization in GUI
• No patch application mechanism
• No rollback capability

Architectural Constraints

Safe Preview

• Patches MUST be previewed before application
• User MUST see exactly what will change
• No automatic application without approval

Atomic Application

• Patch applies all changes or none
• If partial application fails, rollback

Rollback Support

• Backup created before patch
• User can undo applied patch
• Backup stored temporarily

Architecture Reference

Key Integration Points

File	Lines	Purpose
src/ai_client.py	~700-750	run_tier4_analysis()
src/shell_runner.py	50-100	run_powershell() with qa_callback
src/mcp_client.py	300-350	set_file_slice(), edit_file()
src/gui_2.py	2400-2500	Confirmation dialogs pattern

Proposed Patch Workflow

1. Test fails → stderr captured
2. Tier 4 analyzes → generates unified diff
3. GUI shows diff viewer with Apply/Reject buttons
4. User clicks Apply:
   a. Backup original file(s)
   b. Apply patch via subprocess or difflib
   c. Verify patch applied cleanly
   d. If fails, restore from backup
5. Pipeline resumes with patched code

Unified Diff Format

--- a/src/target_file.py
+++ b/src/target_file.py
@@ -10,5 +10,6 @@
 def existing_function():
-    old_line
+    new_line
+    additional_line

Functional Requirements

FR1: Patch Generation

• Tier 4 prompt enhanced to generate unified diff
• Output format: standard diff -u format
• Include file path in diff header
• Multiple files supported

FR2: Diff Viewer GUI

• Side-by-side or unified view
• Color-coded additions (green) and deletions (red)
• Line numbers visible
• Scrollable for large diffs

FR3: Apply Button

• Creates backup: file.py.backup
• Applies patch: patch -p1 < diff.patch or Python difflib
• Verifies success
• Shows confirmation or error

FR4: Rollback

• Restore from backup if patch fails
• Manual rollback button after successful patch
• Backup deleted after explicit user action

Non-Functional Requirements

Requirement	Constraint
Patch Generation	<5s for typical errors
Diff Rendering	<100ms for 100-line diff
Backup Storage	Temp dir, cleaned on exit

Testing Requirements

Unit Tests

• Test diff generation format
• Test patch application logic
• Test backup/rollback

Integration Tests (via live_gui fixture)

• Trigger test failure, verify patch generated
• Apply patch, verify file changed correctly
• Rollback, verify file restored

Out of Scope

• Automatic patch application (always requires approval)
• Patch conflict resolution (reject if conflict)
• Multi-file patch coordination

Acceptance Criteria

• Tier 4 generates valid unified diff on test failure
• GUI displays readable side-by-side diff
• User can approve/reject patch
• Approved patches applied correctly
• Rollback available on failure
• Backup files cleaned up
• 1-space indentation maintained