Add ktfmt hook. am: df057d3b9a

Original change: https://android-review.googlesource.com/c/platform/tools/repohooks/+/2075314

Change-Id: I85107d487da5e67d3597579d5f06aabc098fab3b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

3 files changed, 66 insertions, 0 deletions

diff --git a/README.md b/README.md
index 1954d0a..47bd40b 100644
--- a/README.md
+++ b/README.md
@@ -193,6 +193,9 @@ canned hooks already included geared towards AOSP style guidelines.
 * `google_java_format`: Run Java code through
   [`google-java-format`](https://github.com/google/google-java-format)
 * `jsonlint`: Verify JSON code is sane.
+* `ktfmt`: Run Kotlin code through `ktfmt`. Supports an additional option
+  --include-dirs, which if specified will limit enforcement to only files under
+  the specified directories.
 * `pylint`: Alias of `pylint2`.  Will change to `pylint3` by end of 2019.
 * `pylint2`: Run Python code through `pylint` using Python 2.
 * `pylint3`: Run Python code through `pylint` using Python 3.
@@ -274,6 +277,7 @@ distros/versions.  The following tools are recognized:
 * `gofmt`: used for the `gofmt` builtin hook.
 * `google-java-format`: used for the `google_java_format` builtin hook.
 * `google-java-format-diff`: used for the `google_java_format` builtin hook.
+* `ktfmt`: used for the `ktfmt` builtin hook.
 * `pylint`: used for the `pylint` builtin hook.
 * `rustfmt`: used for the `rustfmt` builtin hook.
 
diff --git a/rh/hooks.py b/rh/hooks.py
index d473cb9..643001c 100644
--- a/rh/hooks.py
+++ b/rh/hooks.py
@@ -397,6 +397,42 @@ def check_google_java_format(project, commit, _desc, _diff, options=None):
                       fixup_func=fixup_func)
 
 
+def check_ktfmt(project, commit, _desc, diff, options=None):
+    """Checks that kotlin files are formatted with ktfmt."""
+
+    include_dir_args = [x for x in options.args()
+                        if x.startswith('--include-dirs=')]
+    include_dirs = [x.removeprefix('--include-dirs=').split(',')
+                    for x in include_dir_args]
+    patterns = [fr'^{x}/.*\.kt$' for dir_list in include_dirs
+                for x in dir_list]
+    if not patterns:
+        patterns = [r'\.kt$']
+
+    filtered = _filter_diff(diff, patterns)
+
+    if not filtered:
+        return None
+
+    args = [x for x in options.args() if x not in include_dir_args]
+
+    ktfmt = options.tool_path('ktfmt')
+    cmd = [ktfmt, '--dry-run'] + args + HookOptions.expand_vars(
+        ('${PREUPLOAD_FILES}',), filtered)
+    result = _run(cmd)
+    if result.stdout:
+        paths = [os.path.join(project.dir, x.file) for x in filtered]
+        error = (
+            f'\nKotlin files need formatting.\n'
+            'To reformat the kotlin files in this commit:\n'
+            f'{ktfmt} {" ".join(paths)}'
+        )
+        fixup_func = _fixup_func_caller([ktfmt] + paths)
+        return [rh.results.HookResult('ktfmt', project, commit, error=error,
+                                      files=paths, fixup_func=fixup_func)]
+    return None
+
+
 def check_commit_msg_bug_field(project, commit, desc, _diff, options=None):
     """Check the commit message for a 'Bug:' line."""
     field = 'Bug'
@@ -1014,6 +1050,7 @@ BUILTIN_HOOKS = {
     'gofmt': check_gofmt,
     'google_java_format': check_google_java_format,
     'jsonlint': check_json,
+    'ktfmt': check_ktfmt,
     'pylint': check_pylint2,
     'pylint2': check_pylint2,
     'pylint3': check_pylint3,
@@ -1034,6 +1071,7 @@ TOOL_PATHS = {
     'gofmt': 'gofmt',
     'google-java-format': 'google-java-format',
     'google-java-format-diff': 'google-java-format-diff.py',
+    'ktfmt': 'ktfmt',
     'pylint': 'pylint',
     'rustfmt': 'rustfmt',
 }
diff --git a/rh/hooks_unittest.py b/rh/hooks_unittest.py
index 03f45ca..389aad8 100755
--- a/rh/hooks_unittest.py
+++ b/rh/hooks_unittest.py
@@ -776,6 +776,30 @@ class BuiltinHooksTests(unittest.TestCase):
 
         # TODO: Actually pass some valid/invalid json data down.
 
+    def test_ktfmt(self, mock_check, _mock_run):
+        """Verify the ktfmt builtin hook."""
+        # First call should do nothing as there are no files to check.
+        ret = rh.hooks.check_ktfmt(
+            self.project, 'commit', 'desc', (), options=self.options)
+        self.assertIsNone(ret)
+        self.assertFalse(mock_check.called)
+        # Check that .kt files are included by default.
+        diff = [rh.git.RawDiffEntry(file='foo.kt'),
+                rh.git.RawDiffEntry(file='bar.java'),
+                rh.git.RawDiffEntry(file='baz/blah.kt')]
+        ret = rh.hooks.check_ktfmt(
+            self.project, 'commit', 'desc', diff, options=self.options)
+        self.assertListEqual(ret[0].files, ['/.../repo/dir/foo.kt',
+                                            '/.../repo/dir/baz/blah.kt'])
+        diff = [rh.git.RawDiffEntry(file='foo/f1.kt'),
+                rh.git.RawDiffEntry(file='bar/f2.kt'),
+                rh.git.RawDiffEntry(file='baz/f2.kt')]
+        ret = rh.hooks.check_ktfmt(self.project, 'commit', 'desc', diff,
+                                   options=rh.hooks.HookOptions('hook name', [
+                                       '--include-dirs=foo,baz'], {}))
+        self.assertListEqual(ret[0].files, ['/.../repo/dir/foo/f1.kt',
+                                            '/.../repo/dir/baz/f2.kt'])
+
     def test_pylint(self, mock_check, _mock_run):
         """Verify the pylint builtin hook."""
         self._test_file_filter(mock_check, rh.hooks.check_pylint2,