afdo_tools: move git utilities into cros_utils

These will be useful soon for an llvm patch cleanup script I'm working
on. Factor them out to reduce maintenance.

BUG=b:332589934
TEST=Unittests & new script

Change-Id: I69114cc8df0a94a8edc9525571d1a7d45d04d369
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/5417086
Reviewed-by: Jordan Abrahams-Whitehead <ajordanr@google.com>
Commit-Queue: George Burgess <gbiv@chromium.org>
Tested-by: George Burgess <gbiv@chromium.org>

4 files changed, 193 insertions, 120 deletions

diff --git a/afdo_tools/update_kernel_afdo.py b/afdo_tools/update_kernel_afdo.py
index fd7ae16c..a7e40763 100755
--- a/afdo_tools/update_kernel_afdo.py
+++ b/afdo_tools/update_kernel_afdo.py
@@ -24,11 +24,11 @@ import sys
 import tempfile
 from typing import Dict, Generator, Iterable, List, Optional, Tuple
 
+from cros_utils import git_utils
+
 
 # Folks who should be on the R-line of any CLs that get uploaded.
-# Note that `c-compiler-chrome@` is managed by gwsq - it'll replace
-# `R=c-compiler-chrome` with the current detective.
-CL_REVIEWERS = ("c-compiler-chrome@google.com",)
+CL_REVIEWERS = (git_utils.REVIEWER_DETECTIVE,)
 
 # Folks who should be on the CC-line of any CLs that get uploaded.
 CL_CC = (
@@ -737,55 +737,24 @@ def commit_new_profiles(
     )
 
 
-def parse_cl_from_upload_output(upload_output: str) -> str:
-    """Returns the CL number in the given upload output."""
-    id_regex = re.compile(
-        r"^remote:\s+https://chromium-review\S+/\+/(\d+)\s", re.MULTILINE
-    )
-
-    results = id_regex.findall(upload_output)
-    if len(results) != 1:
-        raise ValueError(
-            f"Wanted exactly one match for {id_regex} in {upload_output!r}; "
-            f"found {len(results)}"
-        )
-    return results[0]
-
-
 def upload_head_to_gerrit(
     toolchain_utils: Path,
     chromeos_tree: Optional[Path],
     branch: GitBranch,
 ):
     """Uploads HEAD to gerrit as a CL, and sets reviewers/CCs."""
-    option_list = [f"r={x}" for x in CL_REVIEWERS]
-    option_list += (f"cc={x}" for x in CL_CC)
-    options = ",".join(option_list)
-    run_result = subprocess.run(
-        [
-            "git",
-            "push",
-            branch.remote,
-            # https://gerrit-review.googlesource.com/Documentation/user-upload.html#reviewers
-            # for more info on the `%` params.
-            f"HEAD:refs/for/{branch.branch_name}%{options}",
-        ],
-        cwd=toolchain_utils,
-        check=False,
-        stdin=subprocess.DEVNULL,
-        stdout=subprocess.PIPE,
-        stderr=subprocess.STDOUT,
-        encoding="utf-8",
-    )
-
-    logging.info(
-        "`git push`ing to %s had this output:\n%s",
+    cl_ids = git_utils.upload_to_gerrit(
+        toolchain_utils,
+        branch.remote,
         branch.branch_name,
-        run_result.stdout,
+        CL_REVIEWERS,
+        CL_CC,
     )
-    run_result.check_returncode()
 
-    cl_id = parse_cl_from_upload_output(run_result.stdout)
+    if len(cl_ids) > 1:
+        raise ValueError(f"Unexpected: wanted just one CL upload; got {cl_ids}")
+
+    cl_id = cl_ids[0]
     logging.info("Uploaded CL http://crrev.com/c/%s successfully.", cl_id)
 
     if chromeos_tree is None:
@@ -795,29 +764,7 @@ def upload_head_to_gerrit(
         )
         return
 
-    # To make the life of the reviewers marginally easier, click buttons
-    # automatically.
-    gerrit_commands = (
-        ["gerrit", "label-as", cl_id, "1"],
-        ["gerrit", "label-cq", cl_id, "1"],
-        ["gerrit", "label-v", cl_id, "1"],
-    )
-    for cmd in gerrit_commands:
-        # Run the gerrit commands inside of toolchain_utils, since `gerrit`
-        # needs to be run inside of a ChromeOS tree to work. While
-        # `toolchain-utils` can be checked out on its own, that's not how this
-        # script is expeted to be used.
-        return_code = subprocess.run(
-            cmd,
-            cwd=chromeos_tree,
-            check=False,
-            stdin=subprocess.DEVNULL,
-        ).returncode
-        if return_code:
-            logging.warning(
-                "Failed to run gerrit command %s. Ignoring.",
-                shlex.join(cmd),
-            )
+    git_utils.try_set_autosubmit_labels(chromeos_tree, cl_id)
 
 
 def find_chromeos_tree_root(a_dir: Path) -> Optional[Path]:
diff --git a/afdo_tools/update_kernel_afdo_test.py b/afdo_tools/update_kernel_afdo_test.py
index 79ed9d1c..1f365959 100755
--- a/afdo_tools/update_kernel_afdo_test.py
+++ b/afdo_tools/update_kernel_afdo_test.py
@@ -17,44 +17,6 @@ from unittest import mock
 import update_kernel_afdo
 
 
-GERRIT_OUTPUT_WITH_ONE_CL = """
-Enumerating objects: 4, done.
-Counting objects: 100% (4/4), done.
-Delta compression using up to 128 threads
-Compressing objects: 100% (2/2), done.
-Writing objects: 100% (3/3), 320 bytes | 106.00 KiB/s, done.
-Total 3 (delta 1), reused 1 (delta 0), pack-reused 0 (from 0)
-remote: Resolving deltas: 100% (1/1)
-remote: Processing changes: refs: 1, new: 1, done
-remote:
-remote: SUCCESS
-remote:
-remote:   https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/5375204 DO NOT COMMIT [WIP] [NEW]
-remote:
-To https://chromium.googlesource.com/chromiumos/third_party/toolchain-utils
- * [new reference]     HEAD -> refs/for/main
-"""
-
-GERRIT_OUTPUT_WITH_TWO_CLS = """
-Enumerating objects: 4, done.
-Counting objects: 100% (4/4), done.
-Delta compression using up to 128 threads
-Compressing objects: 100% (2/2), done.
-Writing objects: 100% (3/3), 320 bytes | 106.00 KiB/s, done.
-Total 3 (delta 1), reused 1 (delta 0), pack-reused 0 (from 0)
-remote: Resolving deltas: 100% (1/1)
-remote: Processing changes: refs: 1, new: 1, done
-remote:
-remote: SUCCESS
-remote:
-remote:   https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/5375204 DO NOT COMMIT [WIP] [NEW]
-remote:   https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/5375205 DO NOT COMMIT [WIP] [NEW]
-remote:
-To https://chromium.googlesource.com/chromiumos/third_party/toolchain-utils
- * [new reference]     HEAD -> refs/for/main
-"""
-
-
 class Test(unittest.TestCase):
     """Tests for update_kernel_afdo."""
 
@@ -321,22 +283,6 @@ TOTAL: 2 objects, 1234 bytes (1.1KiB)
             update_kernel_afdo.write_afdo_descriptor_file(file_path, contents)
         )
 
-    def test_cl_parsing_from_gerrit_output(self):
-        self.assertEqual(
-            update_kernel_afdo.parse_cl_from_upload_output(
-                GERRIT_OUTPUT_WITH_ONE_CL
-            ),
-            "5375204",
-        )
-
-        with self.assertRaisesRegex(ValueError, ".*; found 0"):
-            update_kernel_afdo.parse_cl_from_upload_output("")
-
-        with self.assertRaisesRegex(ValueError, ".*; found 2"):
-            update_kernel_afdo.parse_cl_from_upload_output(
-                GERRIT_OUTPUT_WITH_TWO_CLS
-            )
-
     def test_repo_autodetects_nothing_if_no_repo_dir(self):
         self.assertIsNone(
             update_kernel_afdo.find_chromeos_tree_root(
diff --git a/cros_utils/git_utils.py b/cros_utils/git_utils.py
new file mode 100644
index 00000000..1ae02ae0
--- /dev/null
+++ b/cros_utils/git_utils.py
@@ -0,0 +1,107 @@
+# Copyright 2024 The ChromiumOS Authors
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Shared utilities for working with git."""
+
+import logging
+from pathlib import Path
+import re
+import shlex
+import subprocess
+from typing import Iterable, List
+
+
+# Email address used to tag the detective as a reviewer.
+REVIEWER_DETECTIVE = "c-compiler-chrome@google.com"
+
+
+def _parse_cls_from_upload_output(upload_output: str) -> List[int]:
+    """Returns the CL number in the given upload output."""
+    id_regex = re.compile(
+        r"^remote:\s+https://chromium-review\S+/\+/(\d+)\s", re.MULTILINE
+    )
+
+    results = id_regex.findall(upload_output)
+    if not results:
+        raise ValueError(
+            f"Wanted at least one match for {id_regex} in {upload_output!r}; "
+            "found 0"
+        )
+    return [int(x) for x in results]
+
+
+def upload_to_gerrit(
+    git_repo: Path,
+    remote: str,
+    branch: str,
+    reviewers: Iterable[str] = (),
+    cc: Iterable[str] = (),
+    ref: str = "HEAD",
+) -> List[int]:
+    """Uploads `ref` to gerrit, optionally adding reviewers/CCs."""
+    # https://gerrit-review.googlesource.com/Documentation/user-upload.html#reviewers
+    # for more info on the `%` params.
+    option_list = [f"r={x}" for x in reviewers]
+    option_list += (f"cc={x}" for x in cc)
+    if option_list:
+        trailing_options = "%" + ",".join(option_list)
+    else:
+        trailing_options = ""
+
+    run_result = subprocess.run(
+        [
+            "git",
+            "push",
+            remote,
+            # https://gerrit-review.googlesource.com/Documentation/user-upload.html#reviewers
+            # for more info on the `%` params.
+            f"{ref}:refs/for/{branch}{trailing_options}",
+        ],
+        cwd=git_repo,
+        check=False,
+        stdin=subprocess.DEVNULL,
+        stdout=subprocess.PIPE,
+        stderr=subprocess.STDOUT,
+        encoding="utf-8",
+    )
+
+    logging.info(
+        "`git push`ing %s to %s/%s had this output:\n%s",
+        ref,
+        remote,
+        branch,
+        run_result.stdout,
+    )
+    run_result.check_returncode()
+    return _parse_cls_from_upload_output(run_result.stdout)
+
+
+def try_set_autosubmit_labels(chromeos_tree: Path, cl_id: int) -> None:
+    """Sets autosubmit on a CL. Logs - not raises - on failure.
+
+    This sets a series of convenience labels on the given cl_number, so landing
+    it (e.g., for the detective) is as easy as possible.
+    """
+    gerrit_cl_id = str(cl_id)
+    gerrit_commands = (
+        ["gerrit", "label-as", gerrit_cl_id, "1"],
+        ["gerrit", "label-cq", gerrit_cl_id, "1"],
+        ["gerrit", "label-v", gerrit_cl_id, "1"],
+    )
+    for cmd in gerrit_commands:
+        # Run the gerrit commands inside of toolchain_utils, since `gerrit`
+        # needs to be run inside of a ChromeOS tree to work. While
+        # `toolchain-utils` can be checked out on its own, that's not how this
+        # script is expeted to be used.
+        return_code = subprocess.run(
+            cmd,
+            cwd=chromeos_tree,
+            check=False,
+            stdin=subprocess.DEVNULL,
+        ).returncode
+        if return_code:
+            logging.warning(
+                "Failed to run gerrit command %s. Ignoring.",
+                shlex.join(cmd),
+            )
diff --git a/cros_utils/git_utils_test.py b/cros_utils/git_utils_test.py
new file mode 100755
index 00000000..2edf1591
--- /dev/null
+++ b/cros_utils/git_utils_test.py
@@ -0,0 +1,73 @@
+#!/usr/bin/env python3
+# Copyright 2024 The ChromiumOS Authors
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+"""Tests for git_utils."""
+
+import unittest
+
+from cros_utils import git_utils
+
+
+# pylint: disable=protected-access
+
+GERRIT_OUTPUT_WITH_ONE_CL = """
+Enumerating objects: 4, done.
+Counting objects: 100% (4/4), done.
+Delta compression using up to 128 threads
+Compressing objects: 100% (2/2), done.
+Writing objects: 100% (3/3), 320 bytes | 106.00 KiB/s, done.
+Total 3 (delta 1), reused 1 (delta 0), pack-reused 0 (from 0)
+remote: Resolving deltas: 100% (1/1)
+remote: Processing changes: refs: 1, new: 1, done
+remote:
+remote: SUCCESS
+remote:
+remote:   https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/5375204 DO NOT COMMIT [WIP] [NEW]
+remote:
+To https://chromium.googlesource.com/chromiumos/third_party/toolchain-utils
+ * [new reference]     HEAD -> refs/for/main
+"""
+
+GERRIT_OUTPUT_WITH_TWO_CLS = """
+Enumerating objects: 4, done.
+Counting objects: 100% (4/4), done.
+Delta compression using up to 128 threads
+Compressing objects: 100% (2/2), done.
+Writing objects: 100% (3/3), 320 bytes | 106.00 KiB/s, done.
+Total 3 (delta 1), reused 1 (delta 0), pack-reused 0 (from 0)
+remote: Resolving deltas: 100% (1/1)
+remote: Processing changes: refs: 1, new: 1, done
+remote:
+remote: SUCCESS
+remote:
+remote:   https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/5375204 DO NOT COMMIT [WIP] [NEW]
+remote:   https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/5375205 DO NOT COMMIT [WIP] [NEW]
+remote:
+To https://chromium.googlesource.com/chromiumos/third_party/toolchain-utils
+ * [new reference]     HEAD -> refs/for/main
+"""
+
+
+class Test(unittest.TestCase):
+    """Tests for git_utils."""
+
+    def test_cl_parsing_complains_if_no_output(self):
+        with self.assertRaisesRegex(ValueError, ".*; found 0"):
+            git_utils._parse_cls_from_upload_output("")
+
+    def test_cl_parsing_works_with_one_cl(self):
+        self.assertEqual(
+            git_utils._parse_cls_from_upload_output(GERRIT_OUTPUT_WITH_ONE_CL),
+            [5375204],
+        )
+
+    def test_cl_parsing_works_with_two_cls(self):
+        self.assertEqual(
+            git_utils._parse_cls_from_upload_output(GERRIT_OUTPUT_WITH_TWO_CLS),
+            [5375204, 5375205],
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()