hooks: add --fix option to auto-apply hook fixes

Pass the --fix flag as a keyword argument "fix" to the hook main
function. This allows hooks (such as git-repohooks) to decouple
automated fix application from the -y/--yes flag so that -y can
answer yes to upload confirmation prompts without triggering file
mutations.

Companion change in git-repohooks:
https://gerrit-review.googlesource.com/c/git-repohooks/+/621761

Bug: 546510319
Test: python3 -m pytest tests/test_hooks.py

Change-Id: If0288d4791fc0a2aba6e88854e3aa81b0923b664
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/619281
Commit-Queue: Rahul Yadav <yadavrah@google.com>
Tested-by: Rahul Yadav <yadavrah@google.com>
Reviewed-by: Gavin Mak <gavinmak@google.com>

6 files changed, 98 insertions, 7 deletions

diff --git a/completion.zsh b/completion.zsh
index 704e584f8..ac82ce78d 100644
--- a/completion.zsh
+++ b/completion.zsh
@@ -400,6 +400,7 @@ _repo() {
         '--no-verify[Do not verify]' \
         '--verify[Verify]' \
         '--ignore-hooks[Ignore hooks]' \
+        '--fix[Automatically fix]' \
         '*: :->project'
       ;;
     version)
diff --git a/docs/repo-hooks.md b/docs/repo-hooks.md
index c3adee8ad..7f69217da 100644
--- a/docs/repo-hooks.md
+++ b/docs/repo-hooks.md
@@ -88,7 +88,14 @@ be useful when deploying automatic fixes.
 If the repo command that triggered the hook supports a "yes" option (e.g.,
 `repo upload --yes`), this option is propagated to the hook's `main` function
 as `yes` parameter (defaulting to `False`).  Hooks can use this to bypass
-interactive confirmation prompts when they can automatically fix issues.
+interactive confirmation prompts for safe non-modifying operations.
+
+### Automated Fixes
+
+If the repo command that triggered the hook supports a "fix" option (e.g.,
+`repo upload --fix`), this option is propagated to the hook's `main` function
+as `fix` parameter (defaulting to `False`).  Hooks can use this to automatically
+apply fixes without prompting the user.
 
 ### Shebang Handling
 
@@ -126,7 +133,7 @@ This hook runs when people run `repo upload`.
 The `pre-upload.py` file should be defined like:
 
 ```py
-def main(project_list, worktree_list=None, yes=False, **kwargs):
+def main(project_list, worktree_list=None, fix=False, yes=False, **kwargs):
     """Main function invoked directly by repo.
 
     We must use the name "main" as that is what repo requires.
@@ -137,6 +144,7 @@ def main(project_list, worktree_list=None, yes=False, **kwargs):
           project_list, so that each entry in project_list matches with a
           directory in worktree_list.  If None, we will attempt to calculate
           the directories automatically.
+      fix: Whether to automatically apply fixes without prompting.
       yes: Whether to answer yes to all safe prompts (see
           [Safe Prompts](#safe-prompts)).
       kwargs: Leave this here for forward-compatibility.
diff --git a/hooks.py b/hooks.py
index 5c763db5e..af3134d5e 100644
--- a/hooks.py
+++ b/hooks.py
@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import optparse
 import os
 import re
 import sys
@@ -69,6 +70,7 @@ class RepoHook:
         ignore_hooks=False,
         abort_if_user_denies=False,
         yes=False,
+        fix=False,
     ):
         """RepoHook constructor.
 
@@ -91,6 +93,7 @@ class RepoHook:
             abort_if_user_denies: If True, we'll abort running the hook if the
                 user doesn't allow us to run the hook.
             yes: If True, then 'Yes' is assumed for any prompts.
+            fix: If True, then 'Fix' is assumed for any fixup prompts.
         """
         self._hook_type = hook_type
         self._hooks_project = hooks_project
@@ -102,6 +105,7 @@ class RepoHook:
         self._ignore_hooks = ignore_hooks
         self._abort_if_user_denies = abort_if_user_denies
         self._yes = yes
+        self._fix = fix
 
         # Store the full path to the script for convenience.
         self._script_fullpath = None
@@ -380,6 +384,7 @@ class RepoHook:
             kwargs = {
                 **kwargs,
                 "hook_should_take_kwargs": True,
+                "fix": self._fix,
                 "yes": self._yes,
             }
 
@@ -504,12 +509,17 @@ class RepoHook:
                 ).url,
                 "bug_url": manifest.contactinfo.bugurl,
                 "yes": getattr(opt, "yes", False),
+                "fix": getattr(opt, "fix", False),
             }
         )
         return cls(*args, **kwargs)
 
     @staticmethod
-    def AddOptionGroup(parser, name):
+    def AddOptionGroup(
+        parser: optparse.OptionParser,
+        name: str,
+        allow_fix: bool = False,
+    ) -> None:
         """Help options relating to the various hooks."""
 
         # Note that verify and no-verify are NOT opposites of each other, which
@@ -533,3 +543,10 @@ class RepoHook:
             action="store_true",
             help="Do not abort if %s hooks fail." % name,
         )
+        if allow_fix:
+            group.add_option(
+                "--fix",
+                action="store_true",
+                default=False,
+                help="Automatically apply %s fixes without prompting." % name,
+            )
diff --git a/man/repo-upload.1 b/man/repo-upload.1
index 02de7b533..ad17b6987 100644
--- a/man/repo-upload.1
+++ b/man/repo-upload.1
@@ -1,5 +1,5 @@
 .\" DO NOT MODIFY THIS FILE!  It was generated by help2man.
-.TH REPO "1" "June 2026" "repo upload" "Repo Manual"
+.TH REPO "1" "August 2026" "repo upload" "Repo Manual"
 .SH NAME
 repo \- repo upload - manual page for repo upload
 .SH SYNOPSIS
@@ -112,6 +112,9 @@ Run the pre\-upload hook without prompting.
 .TP
 \fB\-\-ignore\-hooks\fR
 Do not abort if pre\-upload hooks fail.
+.TP
+\fB\-\-fix\fR
+Automatically apply pre\-upload fixes without prompting.
 .PP
 Run `repo help upload` to view the detailed manual.
 .SH DETAILS
diff --git a/subcmds/upload.py b/subcmds/upload.py
index 56a2066e7..31cdde191 100644
--- a/subcmds/upload.py
+++ b/subcmds/upload.py
@@ -379,7 +379,7 @@ Gerrit Code Review:  https://www.gerritcodereview.com/
             default=True,
             help="disable verifying ssl certs (unsafe)",
         )
-        RepoHook.AddOptionGroup(p, "pre-upload")
+        RepoHook.AddOptionGroup(p, "pre-upload", allow_fix=True)
 
     def _SingleBranch(self, opt, branch, people):
         project = branch.project
diff --git a/tests/test_hooks.py b/tests/test_hooks.py
index 33ccba7b6..3c05d4fe4 100644
--- a/tests/test_hooks.py
+++ b/tests/test_hooks.py
@@ -15,6 +15,7 @@
 """Unittests for the hooks.py module."""
 
 from io import StringIO
+from pathlib import Path
 import sys
 
 import pytest
@@ -108,11 +109,11 @@ def test_post_sync_argument_validation() -> None:
 
 
 @pytest.mark.parametrize("yes_val", (True, False))
-def test_repo_upload_yes_arg(tmp_path, yes_val: bool) -> None:
+def test_repo_upload_yes_arg(tmp_path: Path, yes_val: bool) -> None:
     """Test that yes is passed in kwargs during hook execution."""
 
     class FakeProject:
-        def __init__(self, worktree):
+        def __init__(self, worktree: str) -> None:
             self.worktree = worktree
             self.enabled_repo_hooks = ["pre-upload"]
             self.config = None
@@ -139,3 +140,64 @@ def main(project_list, **kwargs):
 
     assert res is True
     assert project_list == [yes_val]
+
+
+@pytest.mark.parametrize("fix_val", (True, False))
+def test_repo_upload_fix_arg(tmp_path: Path, fix_val: bool) -> None:
+    """Test that fix is passed in kwargs during hook execution."""
+
+    class FakeProject:
+        def __init__(self, worktree: str) -> None:
+            self.worktree = worktree
+            self.enabled_repo_hooks = ["pre-upload"]
+            self.config = None
+
+    hook_file = tmp_path / "pre-upload.py"
+
+    hook_content = """
+def main(project_list, **kwargs):
+    project_list.append(kwargs.get("fix"))
+"""
+    hook_file.write_text(hook_content)
+
+    hook = hooks.RepoHook(
+        hook_type="pre-upload",
+        hooks_project=FakeProject(str(tmp_path)),
+        repo_topdir=str(tmp_path),
+        manifest_url="https://gerrit",
+        allow_all_hooks=True,
+        fix=fix_val,
+    )
+
+    project_list = []
+    res = hook.Run(project_list=project_list, worktree_list=[])
+
+    assert res is True
+    assert project_list == [fix_val]
+
+
+def test_from_subcmd_without_fix_option() -> None:
+    """Test that FromSubcmd works when opt does not have fix attribute."""
+
+    class Remote:
+        url = "https://gerrit"
+
+    class FakeManifest:
+        repo_hooks_project = None
+        topdir = "/fake/topdir"
+
+        class manifestProject:
+            @staticmethod
+            def GetRemote(name: str) -> "Remote":
+                return Remote()
+
+        class contactinfo:
+            bugurl = "https://bugs"
+
+    class FakeOpt:
+        bypass_hooks = False
+        allow_all_hooks = False
+        ignore_hooks = False
+
+    hook = hooks.RepoHook.FromSubcmd(FakeManifest(), FakeOpt(), "post-sync")
+    assert hook._fix is False