refactor(gui_2,patch_modal): merge diff_viewer ops into gui_2; data classes (DiffHunk/DiffFile) move to patch_modal.py alongside PendingPatch; git rm src/diff_viewer.py

Per spec FR1 + Phase 1.4 + architecture feedback (data != view):
  - Data classes DiffHunk, DiffFile -> src/patch_modal.py (alongside PendingPatch; all patch-domain data)
  - Operations parse_diff/parse_hunk_header/get_line_color/apply_patch_to_file (called by gui_2) -> src/gui_2.py
  - GUI is a pure view; data lives elsewhere; no new files per AGENTS.md

Tests: tests/test_diff_viewer.py imports from src.gui_2 (parse_diff/apply_patch_to_file) and src.patch_modal (DiffFile/DiffHunk).

src/diff_viewer.py

@@ -1,173 +0,0 @@
-import difflib
-import shutil
-import os
-
-from dataclasses import dataclass
-from pathlib     import Path
-from typing      import List, Dict, Optional, Tuple
-
-from src.result_types import ErrorInfo, ErrorKind, Result
-
-
-@dataclass
-class DiffHunk:
- header:    str
- lines:     List[str]
- old_start: int
- old_count: int
- new_start: int
- new_count: int
-
-@dataclass  
-class DiffFile:
- old_path: str
- new_path: str
- hunks:    List[DiffHunk]
-
-def parse_hunk_header(line: str) -> tuple[int, int, int, int]:
- """
- [C: tests/test_diff_viewer.py:test_parse_hunk_header]
- """
- if not line.startswith("@@"): return (-1, -1, -1, -1)
- 
- parts = line.split()
- if len(parts) < 2: return (-1, -1, -1, -1)
- 
- old_part = parts[1][1:]
- new_part = parts[2][1:]
- 
- old_parts = old_part.split(",")
- new_parts = new_part.split(",")
- 
- old_start = int(old_parts[0])
- old_count = int(old_parts[1]) if len(old_parts) > 1 else 1
- new_start = int(new_parts[0])
- new_count = int(new_parts[1]) if len(new_parts) > 1 else 1
- 
- return (old_start, old_count, new_start, new_count)
-
-def parse_diff(diff_text: str) -> List[DiffFile]:
- """
-  [C: src/gui_2.py:App.request_patch_from_tier4, tests/test_diff_viewer.py:test_diff_line_classification, tests/test_diff_viewer.py:test_parse_diff_empty, tests/test_diff_viewer.py:test_parse_diff_none, tests/test_diff_viewer.py:test_parse_diff_with_context, tests/test_diff_viewer.py:test_parse_multiple_files, tests/test_diff_viewer.py:test_parse_simple_diff]
- """
- if not diff_text or not diff_text.strip():
-  return []
- 
- files:        List[DiffFile] = []
- current_file: Optional[DiffFile] = None
- current_hunk: Optional[DiffHunk] = None
- 
- for line in diff_text.split("\n"):
-  if line.startswith("--- "):
-   if current_file:
-    if current_hunk:
-     current_file.hunks.append(current_hunk)
-     current_hunk = None
-    files.append(current_file)
-   
-   path = line[4:]
-   if path.startswith("a/"):
-    path = path[2:]
-   current_file = DiffFile(old_path=path, new_path="", hunks=[])
-   
-  elif line.startswith("+++ ") and current_file:
-   path = line[4:]
-   if path.startswith("b/"):
-    path = path[2:]
-   current_file.new_path = path
-   
-  elif line.startswith("@@") and current_file:
-   if current_hunk:
-    current_file.hunks.append(current_hunk)
-   
-   hunk_info = parse_hunk_header(line)
-   if hunk_info:
-    old_start, old_count, new_start, new_count = hunk_info
-    current_hunk = DiffHunk(
-     header    = line,
-     lines     = [],
-     old_start = old_start,
-     old_count = old_count,
-     new_start = new_start,
-     new_count = new_count
-    )
-   else:
-    current_hunk = DiffHunk(
-     header    = line,
-     lines     = [],
-     old_start = 0,
-     old_count = 0,
-     new_start = 0,
-     new_count = 0
-    )
-    
-  elif current_hunk is not None:
-   current_hunk.lines.append(line)
-   
-  elif line and not line.startswith("diff ") and not line.startswith("index "):
-   pass
- 
- if current_file:
-  if current_hunk:
-   current_file.hunks.append(current_hunk)
-  files.append(current_file)
- 
- return files
-
-def get_line_color(line: str) -> str:
- """
- [C: tests/test_diff_viewer.py:test_get_line_color]
- """
- if   line.startswith("+"):  return "green"
- elif line.startswith("-"):  return "red"
- elif line.startswith("@@"): return "cyan"
- return ""
-
-def apply_patch_to_file(patch_text: str, base_dir: str = ".") -> Tuple[bool, str]:
- """
- [C: src/gui_2.py:App._apply_pending_patch, tests/test_diff_viewer.py:test_apply_patch_simple, tests/test_diff_viewer.py:test_apply_patch_with_context]
- """
- diff_files = parse_diff(patch_text)
- if not diff_files:
-  return False, "No valid diff found"
- 
- results = []
- for df in diff_files:
-  file_path = Path(base_dir) / df.old_path
-  if not file_path.exists():
-   results.append(f"File not found: {file_path}")
-   continue
-  
-  try:
-   with open(file_path, "r", encoding="utf-8") as f:
-    original_lines = f.read().splitlines(keepends=True)
-   
-   new_lines = original_lines.copy()
-   offset    = 0
-   
-   for hunk in df.hunks:
-    hunk_old_start = hunk.old_start - 1
-    hunk_old_count = hunk.old_count
-    
-    replace_start = hunk_old_start + offset
-    replace_count = hunk_old_count
-    
-    hunk_new_content: List[str] = []
-    for line in hunk.lines:
-     if line.startswith("+") and not line.startswith("+++"): 
-      hunk_new_content.append(line[1:] + "\n")
-     elif line.startswith(" ") or (line and not line.startswith(("-", "+", "@@"))):
-      hunk_new_content.append(line + "\n")
-    
-    new_lines = new_lines[:replace_start] + hunk_new_content + new_lines[replace_start + replace_count:]
-    offset   += len(hunk_new_content) - replace_count
-   
-   with open(file_path, "w", encoding="utf-8", newline="") as f:
-    f.writelines(new_lines)
-   
-   results.append(f"Patched: {file_path}")
-  except (OSError, ValueError, IndexError) as e:
-   _patch_err_result = Result(data=False, errors=[ErrorInfo(kind=ErrorKind.INTERNAL, message=f"Error patching {file_path}: {e}", source="diff_viewer.apply_patch_to_file", original=e)])
-   return _patch_err_result.data, _patch_err_result.errors[0].message
- 
- return True, "\n".join(results)

src/gui_2.py

@@ -96,7 +96,6 @@ np         = _LazyModule("numpy")  # was: import numpy as np
 filedialog = _LazyModule("tkinter", "filedialog")  # was: from tkinter import filedialog
 Tk         = _LazyModule("tkinter", "Tk")  # was: from tkinter import Tk
 
-from src.diff_viewer import apply_patch_to_file
 from src import ai_client
 from src import aggregate
 from src import api_hooks
@@ -8115,7 +8114,6 @@ def request_patch_from_tier4_result(app: "App", error: str, file_context: str) -
 
  [C: src/gui_2.py:App.request_patch_from_tier4 (L1428 legacy wrapper)]
  """
- from src.diff_viewer import parse_diff
  try:
   patch_text = ai_client.run_tier4_patch_generation(error, file_context)
   if patch_text and "---" in patch_text and "+++" in patch_text:
@@ -8508,6 +8506,149 @@ def draw_soft_shadow(draw_list: imgui.ImDrawList, p_min: imgui.ImVec2, p_max: im
   )
 #endregion: Shaders
 
+#region: Diff Viewer Operations (data classes live in src/patch_modal.py alongside PendingPatch; ops that gui_2 calls live here)
+import difflib as _diff_difflib
+import shutil as _diff_shutil
+import os as _diff_os
+from pathlib     import Path as _diff_Path
+from typing      import List as _diff_List, Optional as _diff_Optional, Tuple as _diff_Tuple
+from src.patch_modal import DiffHunk, DiffFile
+
+def parse_hunk_header(line: str) -> tuple[int, int, int, int]:
+ if not line.startswith("@@"): return (-1, -1, -1, -1)
+ parts = line.split()
+ if len(parts) < 2: return (-1, -1, -1, -1)
+ old_part = parts[1][1:]
+ new_part = parts[2][1:]
+ old_parts = old_part.split(",")
+ new_parts = new_part.split(",")
+ old_start = int(old_parts[0])
+ old_count = int(old_parts[1]) if len(old_parts) > 1 else 1
+ new_start = int(new_parts[0])
+ new_count = int(new_parts[1]) if len(new_parts) > 1 else 1
+ return (old_start, old_count, new_start, new_count)
+
+def parse_diff(diff_text: str) -> _diff_List[DiffFile]:
+ if not diff_text or not diff_text.strip():
+  return []
+ files:        _diff_List[DiffFile] = []
+ current_file: _diff_Optional[DiffFile] = None
+ current_hunk: _diff_Optional[DiffHunk] = None
+ for line in diff_text.split("\n"):
+  if line.startswith("--- "):
+   if current_file:
+    if current_hunk:
+     current_file.hunks.append(current_hunk)
+     current_hunk = None
+    files.append(current_file)
+   path = line[4:]
+   if path.startswith("a/"):
+    path = path[2:]
+   current_file = DiffFile(old_path=path, new_path="", hunks=[])
+  elif line.startswith("+++ ") and current_file:
+   path = line[4:]
+   if path.startswith("b/"):
+    path = path[2:]
+   current_file.new_path = path
+  elif line.startswith("@@") and current_file:
+   if current_hunk:
+    current_file.hunks.append(current_hunk)
+   hunk_info = parse_hunk_header(line)
+   if hunk_info:
+    old_start, old_count, new_start, new_count = hunk_info
+    current_hunk = DiffHunk(
+     header    = line,
+     lines     = [],
+     old_start = old_start,
+     old_count = old_count,
+     new_start = new_start,
+     new_count = new_count
+    )
+   else:
+    current_hunk = DiffHunk(
+     header    = line,
+     lines     = [],
+     old_start = 0,
+     old_count = 0,
+     new_start = 0,
+     new_count = 0
+    )
+  elif current_hunk is not None:
+   current_hunk.lines.append(line)
+  elif line and not line.startswith("diff ") and not line.startswith("index "):
+   pass
+ if current_file:
+  if current_hunk:
+   current_file.hunks.append(current_hunk)
+  files.append(current_file)
+ return files
+
+def get_line_color(line: str) -> str:
+ if   line.startswith("+"):  return "green"
+ elif line.startswith("-"):  return "red"
+ elif line.startswith("@@"): return "cyan"
+ return ""
+
+def apply_patch_to_file(patch_text: str, base_dir: str = ".") -> _diff_Tuple[bool, str]:
+ diff_files = parse_diff(patch_text)
+ if not diff_files:
+  return False, "No valid diff found"
+ results = []
+ for df in diff_files:
+  file_path = _diff_Path(base_dir) / df.old_path
+  if not file_path.exists():
+   results.append(f"File not found: {file_path}")
+   continue
+  try:
+   with open(file_path, "r", encoding="utf-8") as f:
+    original_lines = f.read().splitlines(keepends=True)
+   new_lines = original_lines.copy()
+   offset    = 0
+   for hunk in df.hunks:
+    hunk_old_start = hunk.old_start - 1
+    hunk_old_count = hunk.old_count
+    replace_start = hunk_old_start + offset
+    replace_count = hunk_old_count
+    hunk_new_content: _diff_List[str] = []
+    for line in hunk.lines:
+     if line.startswith("+") and not line.startswith("+++"):
+      hunk_new_content.append(line[1:] + "\n")
+     elif line.startswith(" ") or (line and not line.startswith(("-", "+", "@@"))):
+      hunk_new_content.append(line + "\n")
+    new_lines = new_lines[:replace_start] + hunk_new_content + new_lines[replace_start + replace_count:]
+    offset   += len(hunk_new_content) - replace_count
+   with open(file_path, "w", encoding="utf-8", newline="") as f:
+    f.writelines(new_lines)
+   results.append(f"Patched: {file_path}")
+  except (OSError, ValueError, IndexError) as e:
+   _patch_err_result = Result(data=False, errors=[ErrorInfo(kind=ErrorKind.INTERNAL, message=f"Error patching {file_path}: {e}", source="diff_viewer.apply_patch_to_file", original=e)])
+   return _patch_err_result.data, _patch_err_result.errors[0].message
+ return True, "\n".join(results)
+#endregion: Diff Viewer Operations
+def draw_soft_shadow(draw_list: imgui.ImDrawList, p_min: imgui.ImVec2, p_max: imgui.ImVec2, color: imgui.ImVec4, shadow_size: float = 10.0, rounding: float = 0.0) -> None:
+ r, g, b, a = color.x, color.y, color.z, color.w
+ steps      = int(shadow_size)
+ if steps <= 0: return
+ alpha_step = a / steps
+ for i in range(steps):
+  current_alpha = a - (i * alpha_step)
+  current_alpha = current_alpha * (1.0 - (i / steps)**2)
+  if current_alpha <= 0.01:
+   continue
+  expand = float(i)
+  c_min = imgui.ImVec2(p_min.x - expand, p_min.y - expand)
+  c_max = imgui.ImVec2(p_max.x + expand, p_max.y + expand)
+  u32_color = imgui.get_color_u32(imgui.ImVec4(r, g, b, current_alpha))
+  draw_list.add_rect(
+   c_min,
+   c_max,
+   u32_color,
+   rounding + expand if rounding > 0 else 0.0,
+   flags=imgui.ImDrawFlags_.round_corners_all if rounding > 0 else imgui.ImDrawFlags_.none,
+   thickness=1.0
+  )
+#endregion: Shaders
+
 #region: Command Palette Modal (rendering only; registry lives in src/commands.py)
 from src.commands import Command as _CpCommand, fuzzy_match as _cp_fuzzy_match, _close_palette, _execute as _cp_execute
 

src/patch_modal.py

@@ -2,6 +2,21 @@ from dataclasses import dataclass, field
 from typing      import Optional, Callable, List
 
 
+@dataclass
+class DiffHunk:
+ header:    str
+ lines:     List[str]
+ old_start: int
+ old_count: int
+ new_start: int
+ new_count: int
+
+@dataclass
+class DiffFile:
+ old_path: str
+ new_path: str
+ hunks:    List[DiffHunk] = field(default_factory=list)
+
 @dataclass
 class PendingPatch:
  patch_text:   str = ""

tests/test_diff_viewer.py

@@ -2,7 +2,7 @@ import pytest
 import tempfile
 import os
 from pathlib import Path
-from src.diff_viewer import (
+from src.gui_2 import (
  parse_diff, DiffFile, DiffHunk, parse_hunk_header,
  get_line_color, apply_patch_to_file
 )