test_simple_diff.py

#!/usr/bin/env python3
"""
Simple test to verify diff parsing with the correct file structure
"""

def apply_unified_diff_to_content(original_content: str, diff_content: str) -> str:
    """
    Applies a unified diff or git diff string to the original content string.
    Returns the patched content.
    Raises ValueError if the patch cannot be applied cleanly.
    """
    diff_content = diff_content.strip()

    # Check if this is a git diff format (starts with diff --git)
    if diff_content.startswith("diff --git") or diff_content.startswith("---"):
        try:
            # Parse the unified diff properly
            lines = diff_content.split('\n')
            original_lines = original_content.split('\n')
            new_lines = original_lines.copy()
            
            # Find all hunks in the diff
            hunks = []
            current_hunk = None
            
            for line in lines:
                if line.startswith('@@ '):
                    # Parse the hunk header: @@ -start,count +start,count @@
                    # Example: @@ -69,7 +69,9 @@
                    parts = line.split(' ')
                    if len(parts) >= 3:
                        old_range = parts[1]  # -69,7
                        new_range = parts[2]  # +69,9
                        
                        old_start = int(old_range.split(',')[0][1:])  # 69
                        new_start = int(new_range.split(',')[0][1:])  # 69
                        
                        current_hunk = {
                            'old_start': old_start,
                            'new_start': new_start,
                            'lines': []
                        }
                        hunks.append(current_hunk)
                elif current_hunk is not None:
                    current_hunk['lines'].append(line)
            
            # Apply hunks in reverse order to maintain line numbers
            for hunk in reversed(hunks):
                old_start = hunk['old_start'] - 1  # Convert to 0-based index
                new_start = hunk['new_start'] - 1  # Convert to 0-based index
                
                # Calculate how many lines to remove
                lines_to_remove = 0
                lines_to_add = []
                
                for line in hunk['lines']:
                    if line.startswith('-'):
                        lines_to_remove += 1
                    elif line.startswith('+'):
                        lines_to_add.append(line[1:])
                    elif line.startswith(' '):
                        # Context line, skip
                        pass
                
                # Apply the changes
                if lines_to_remove > 0:
                    del new_lines[old_start:old_start + lines_to_remove]
                
                if lines_to_add:
                    new_lines[old_start:old_start] = lines_to_add
            
            # Join the lines back together
            new_content = '\n'.join(new_lines)
            return new_content
            
        except Exception as e:
            raise ValueError(f"Failed to parse unified diff: {str(e)}")

    raise ValueError("Could not parse diff content. Ensure it's in the correct format.")

def test_diff_parsing():
    """Test the diff parsing with a simple file structure"""
    
    # This is the file structure that the diff expects
    original_content = '''from flask import Flask, request, jsonify
import os

app = Flask(__name__)

@app.route('/trigger-error', methods=['GET'])
def trigger_error():
    error_enabled = request.args.get('error', 'false').lower() == 'true'
    
    if error_enabled:
        # INTENTIONAL ERROR: This will cause a NameError because 'undefined_variable' is not defined
        # This is the error that can be fixed in a PR
        result = undefined_variable + "This should cause an error"
        return jsonify({'result': result})
    else:
        return jsonify({
            'message': 'Error not triggered. Add ?error=true to trigger the error.',
            'status': 'ok'
        })

@app.route('/health', methods=['GET'])
def health_check():
    return jsonify({'status': 'healthy'})

@app.errorhandler(404)
def not_found(error):
    return jsonify({'error': 'Not found'}), 404

@app.errorhandler(500)
def internal_error(error):
    return jsonify({'error': 'Internal server error'}), 500

if __name__ == '__main__':
    port = int(os.environ.get('PORT', 5000))
    app.run(host='0.0.0.0', port=port, debug=True) '''

    # The actual diff from the user's curl command
    diff_content = '''diff --git a/app.py b/app.py
index c8cba05..d3349e5 100644
--- a/app.py
+++ b/app.py
@@ -69,7 +69,9 @@ def trigger_error():
     if error_enabled:
         # INTENTIONAL ERROR: This will cause a NameError because 'undefined_variable' is not defined
         # This is the error that can be fixed in a PR
+        #result = undefined_variable + "This should cause an error"
         result = undefined_variable + "This should cause an error"
+        result1 = undefined_variable + "This should cause an error"
         return jsonify({'result': result})
     else:
         return jsonify({
@@ -117,4 +119,4 @@ def internal_error(error):
 
 if __name__ == '__main__':
     port = int(os.environ.get('PORT', 5000))
-    app.run(host='0.0.0.0', port=port, debug=True) \n\\ No newline at end of file
+    app.run(host='0.0.0.0', port=port, debug=True) "'''

    print("Testing diff parsing with correct file structure...")
    print("=" * 60)
    
    try:
        # Apply the diff
        result = apply_unified_diff_to_content(original_content, diff_content)
        
        print("✅ Diff applied successfully!")
        print(f"Original content length: {len(original_content)} characters")
        print(f"Modified content length: {len(result)} characters")
        
        # Show the differences
        original_lines = original_content.split('\n')
        result_lines = result.split('\n')
        
        print(f"\nOriginal file has {len(original_lines)} lines")
        print(f"Modified file has {len(result_lines)} lines")
        
        # Show the specific changes around line 69-77
        print("\nChanges around line 69-77:")
        print("-" * 30)
        for i in range(68, 80):
            if i < len(original_lines):
                print(f"Original {i+1:3d}: {original_lines[i]}")
            if i < len(result_lines):
                print(f"Modified {i+1:3d}: {result_lines[i]}")
            print()
        
        # Show the end of file changes
        print("End of file changes:")
        print("-" * 30)
        for i in range(max(0, len(original_lines)-5), len(original_lines)):
            if i < len(original_lines):
                print(f"Original {i+1:3d}: {original_lines[i]}")
        print()
        for i in range(max(0, len(result_lines)-5), len(result_lines)):
            if i < len(result_lines):
                print(f"Modified {i+1:3d}: {result_lines[i]}")
        
    except Exception as e:
        print(f"❌ Error applying diff: {str(e)}")
        import traceback
        traceback.print_exc()

if __name__ == "__main__":
    test_diff_parsing()