fix(loop): resolve P0-1 (B-7) git diff CWD isolation and untracked file capture (20/20 PASS)

2026-08-11 09:39:57 +09:00
parent 64cde54e89
commit f8084cd927
8 changed files with 533 additions and 23 deletions
@@ -0,0 +1,132 @@
+#!/usr/bin/env bash
+# diff_collect.sh — Helper module for collecting git changes and untracked files (B-7)
+# Single source of truth for collecting review diffs.
+
+MAM_DIFF_UNAVAILABLE_MARKER="!!! CHANGE SET UNAVAILABLE !!!"
+MAM_DIFF_TRUNCATED_MARKER="!!! DIFF TRUNCATED !!!"
+MAM_DIFF_NESTED_MARKER="!!! NOT EXPANDED IN THIS DIFF !!!"
+
+MAM_DIFF_MAX_BYTES="${MAM_DIFF_MAX_BYTES:-200000}"
+MAM_DIFF_MAX_LINES="${MAM_DIFF_MAX_LINES:-4000}"
+
+_mam_nested_dir_diff() {
+  local d="$1" outer_top="$2" inner_top=""
+  inner_top=$(git -C "$d" rev-parse --show-toplevel 2>/dev/null || printf '')
+
+  if [ -n "$inner_top" ] && [ "$inner_top" != "$outer_top" ]; then
+    printf '%s %s\n' "$MAM_DIFF_NESTED_MARKER" "$d"
+    printf 'Untracked NESTED GIT REPOSITORY. Its contents are listed through its own\n'
+    printf 'git, so its .gitignore applies; the outer diff cannot describe it.\n\n'
+    git -C "$d" diff 2>/dev/null || true
+    git -C "$d" ls-files -o --exclude-standard -z 2>/dev/null | while IFS= read -r -d '' s; do
+      [ -n "$s" ] || continue
+      git -C "$d" diff --no-index -- /dev/null "$s" 2>/dev/null || true
+    done
+    printf '\n'
+    return 0
+  fi
+
+  printf '%s %s (untracked directory)\n' "$MAM_DIFF_NESTED_MARKER" "$d"
+  git ls-files -o --exclude-standard -z -- "$d" 2>/dev/null | while IFS= read -r -d '' s; do
+    [ -n "$s" ] || continue
+    [ -f "$s" ] && [ ! -L "$s" ] || continue
+    git diff --no-index -- /dev/null "$s" 2>/dev/null || true
+  done
+}
+
+_mam_untracked_diff() {
+  local outer_top
+  outer_top=$(git rev-parse --show-toplevel 2>/dev/null || printf '%s' "$PWD")
+  git ls-files -o --exclude-standard -z 2>/dev/null | while IFS= read -r -d '' f; do
+    [ -n "$f" ] || continue
+    if [ -L "$f" ]; then
+      printf '%s %s -> %s (symlink, not expanded)\n' \
+        "$MAM_DIFF_NESTED_MARKER" "$f" "$(readlink "$f" 2>/dev/null)"
+    elif [ -d "$f" ]; then
+      _mam_nested_dir_diff "$f" "$outer_top"
+    elif [ -f "$f" ]; then
+      git diff --no-index -- /dev/null "$f" 2>/dev/null || true
+    else
+      printf '%s %s (unreadable entry, not shown)\n' "$MAM_DIFF_NESTED_MARKER" "$f"
+    fi
+  done
+}
+
+mam_collect_changes_diff() {
+  local repo_root="${1:-}"
+  local base_commit="${2:-}"
+
+  if [ -z "$repo_root" ]; then
+    printf '%s\nreason: repo_root parameter is required\n' "$MAM_DIFF_UNAVAILABLE_MARKER"
+    return 2
+  fi
+
+  if [ ! -d "$repo_root" ]; then
+    printf '%s\nreason: repo_root directory %s does not exist\n' "$MAM_DIFF_UNAVAILABLE_MARKER" "$repo_root"
+    return 2
+  fi
+
+  local raw_diff="" rc=0
+  raw_diff=$(
+    cd -P "$repo_root" 2>/dev/null || exit 3
+    git rev-parse --git-dir >/dev/null 2>&1 || exit 4
+    if [ -n "$base_commit" ] && git cat-file -e "${base_commit}^{commit}" 2>/dev/null; then
+      git diff "$base_commit" || exit 5
+    else
+      git diff || exit 5
+    fi
+    _mam_untracked_diff
+  ) || rc=$?
+
+  if [ "$rc" -ne 0 ]; then
+    local reason="not a git repository or git command failed (exit code $rc)"
+    if [ "$rc" -eq 3 ]; then
+      reason="cannot cd into repo_root $repo_root"
+    elif [ "$rc" -eq 4 ]; then
+      reason="not a git repository: $repo_root"
+    elif [ "$rc" -eq 5 ]; then
+      reason="git diff command failed"
+    fi
+    printf '%s\nreason: %s\n' "$MAM_DIFF_UNAVAILABLE_MARKER" "$reason"
+    return 2
+  fi
+
+  if [ -z "$(printf '%s' "$raw_diff" | tr -d '[:space:]')" ]; then
+    printf '(no changes since base commit)\n'
+    return 0
+  fi
+
+  local byte_cnt line_cnt
+  byte_cnt=$(printf '%s' "$raw_diff" | wc -c | tr -d '[:space:]')
+  line_cnt=$(printf '%s' "$raw_diff" | wc -l | tr -d '[:space:]')
+
+  if [ "$byte_cnt" -gt "$MAM_DIFF_MAX_BYTES" ] || [ "$line_cnt" -gt "$MAM_DIFF_MAX_LINES" ]; then
+    local stat_summary=""
+    stat_summary=$(
+      cd -P "$repo_root" 2>/dev/null || exit 0
+      if [ -n "$base_commit" ] && git cat-file -e "${base_commit}^{commit}" 2>/dev/null; then
+        git diff "$base_commit" --stat 2>/dev/null || true
+      else
+        git diff --stat 2>/dev/null || true
+      fi
+      printf '\nUntracked files:\n'
+      git ls-files -o --exclude-standard 2>/dev/null || true
+    )
+
+    printf '%s\n' "$MAM_DIFF_TRUNCATED_MARKER"
+    printf 'The change set is %s bytes / %s lines, over the review limit (%s bytes / %s lines).\n' \
+      "$byte_cnt" "$line_cnt" "$MAM_DIFF_MAX_BYTES" "$MAM_DIFF_MAX_LINES"
+    printf 'Only the file-level summary is shown below. You have NOT been shown the\n'
+    printf 'full change set -- inspect the working tree directly before voting.\n\n'
+    printf '%s\n\n' "$stat_summary"
+    printf '%s\n' "$MAM_DIFF_TRUNCATED_MARKER"
+    return 0
+  fi
+
+  printf '%s\n' "$raw_diff"
+  return 0
+}
+
+if [ "${BASH_SOURCE[0]}" = "$0" ]; then
+  mam_collect_changes_diff "$@"
+fi