1 files changed, 94 insertions, 0 deletions
diff --git a/support/git-set-file-times b/support/git-set-file-times
new file mode 100755
index 0000000..e06f073
--- /dev/null
+++ b/support/git-set-file-times
@@ -0,0 +1,94 @@
+#!/usr/bin/env python3
+
+import os, re, argparse, subprocess
+from datetime import datetime
+
+NULL_COMMIT_RE = re.compile(r'\0\0commit [a-f0-9]{40}$|\0$')
+
+def main():
+    if not args.git_dir:
+        cmd = 'git rev-parse --show-toplevel 2>/dev/null || echo .'
+        top_dir = subprocess.check_output(cmd, shell=True, encoding='utf-8').strip()
+        args.git_dir = os.path.join(top_dir, '.git')
+        if not args.prefix:
+            os.chdir(top_dir)
+
+    git = [ 'git', '--git-dir=' + args.git_dir ]
+
+    if args.tree:
+        cmd = git + 'ls-tree -z -r --name-only'.split() + [ args.tree ]
+    else:
+        cmd = git + 'ls-files -z'.split()
+
+    proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, encoding='utf-8')
+    out = proc.communicate()[0]
+    ls = set(out.split('\0'))
+    ls.discard('')
+
+    if not args.tree:
+        # All modified files keep their current mtime.
+        proc = subprocess.Popen(git + 'status -z --no-renames'.split(), stdout=subprocess.PIPE, encoding='utf-8')
+        out = proc.communicate()[0]
+        for fn in out.split('\0'):
+            if fn == '' or (fn[0] != 'M' and fn[1] != 'M'):
+                continue
+            fn = fn[3:]
+            if args.list:
+                mtime = os.lstat(fn).st_mtime
+                print_line(fn, mtime, mtime)
+            ls.discard(fn)
+
+    cmd = git + 'log -r --name-only --format=%x00commit%x20%H%n%x00commit_time%x20%ct%n --no-renames -z'.split()
+    if args.tree:
+        cmd.append(args.tree)
+    cmd += ['--'] + args.files
+
+    proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, encoding='utf-8')
+    for line in proc.stdout:
+        line = line.strip()
+        m = re.match(r'^\0commit_time (\d+)$', line)
+        if m:
+            commit_time = int(m[1])
+        elif NULL_COMMIT_RE.search(line):
+            line = NULL_COMMIT_RE.sub('', line)
+            files = set(fn for fn in line.split('\0') if fn in ls)
+            if not files:
+                continue
+            for fn in files:
+                if args.prefix:
+                    fn = args.prefix + fn
+                mtime = os.lstat(fn).st_mtime
+                if args.list:
+                    print_line(fn, mtime, commit_time)
+                elif mtime != commit_time:
+                    if not args.quiet:
+                        print(f"Setting {fn}")
+                    os.utime(fn, (commit_time, commit_time), follow_symlinks = False)
+            ls -= files
+            if not ls:
+                break
+    proc.communicate()
+
+
+def print_line(fn, mtime, commit_time):
+    if args.list > 1:
+        ts = str(commit_time).rjust(10)
+    else:
+        ts = datetime.utcfromtimestamp(commit_time).strftime("%Y-%m-%d %H:%M:%S")
+    chg = '.' if mtime == commit_time else '*'
+    print(chg, ts, fn)
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(description="Set the times of the files in the current git checkout to their last-changed time.", add_help=False)
+    parser.add_argument('--git-dir', metavar='GIT_DIR', help="The git dir to query (defaults to affecting the current git checkout).")
+    parser.add_argument('--tree', metavar='TREE-ISH', help="The tree-ish to query (defaults to the current branch).")
+    parser.add_argument('--prefix', metavar='PREFIX_STR', help="Prepend the PREFIX_STR to each filename we tweak (defaults to the top of current checkout).")
+    parser.add_argument('--quiet', '-q', action='store_true', help="Don't output the changed-file information.")
+    parser.add_argument('--list', '-l', action='count', help="List files & times instead of changing them. Repeat for Unix timestamp instead of human readable.")
+    parser.add_argument('files', metavar='FILE', nargs='*', help="Specify a subset of checked-out files to tweak.")
+    parser.add_argument("--help", "-h", action="help", help="Output this help message and exit.")
+    args = parser.parse_args()
+    main()
+
+# vim: sw=4 et