feat(commands/commit): apply prepare-commit-msg hook

add --commit-msg-file argument

Author: saygox

.pre-commit-hooks.yaml

@@ -25,3 +25,12 @@
   language: python
   language_version: python3
   minimum_pre_commit_version: "1.4.3"
+
+- id: commitizen-prepare-commit-msg
+  name: commitizen prepare commit msg
+  description: "prepare commit message"
+  entry: cz commit --commit-msg-file
+  language: python
+  language_version: python3
+  require_serial: true
+  minimum_pre_commit_version: "1.4.3"

commitizen/cli.py

@@ -174,6 +174,14 @@ def __call__(
                         "dest": "double_dash",
                         "help": "Positional arguments separator (recommended)",
                     },
+                    {
+                        "name": "--commit-msg-file",
+                        "help": (
+                            "ask for the name of the temporal file that contains "
+                            "the commit message. "
+                            "Using it in a git hook script: MSG_FILE=$1"
+                        ),
+                    },
                 ],
             },
             {

commitizen/commands/commit.py

@@ -4,6 +4,7 @@
 import os
 import shutil
 import subprocess
+import sys
 import tempfile
 
 import questionary
@@ -26,6 +27,21 @@
 from commitizen.git import smart_open
 
 
+class WrapStdin:
+    def __init__(self):
+        fd = os.open("/dev/tty", os.O_RDWR | os.O_NOCTTY)
+        tty = open(fd, "wb+", buffering=0)
+        self.tty = tty
+
+    def __getattr__(self, key):
+        if key == "encoding":
+            return "UTF-8"
+        return getattr(self.tty, key)
+
+    def __del__(self):
+        self.tty.close()
+
+
 class Commit:
     """Show prompt for the user to create a guided commit."""
 
@@ -105,6 +121,15 @@ def __call__(self):
         if is_all:
             c = git.add("-u")
 
+        commit_msg_file: str = self.arguments.get("commit_msg_file")
+        if commit_msg_file:
+            old_stdin = sys.stdin
+            old_stdout = sys.stdout
+            old_stderr = sys.stderr
+            sys.stdin = WrapStdin()
+            sys.stdout = open("/dev/tty", "w")
+            sys.stderr = open("/dev/tty", "w")
+
         if git.is_staging_clean() and not (dry_run or allow_empty):
             raise NothingToCommitError("No files added to staging!")
 
@@ -138,9 +163,24 @@ def __call__(self):
         if dry_run:
             raise DryRunExit()
 
+        if commit_msg_file:
+            sys.stdin.close()
+            sys.stdout.close()
+            sys.stderr.close()
+            sys.stdin = old_stdin
+            sys.stdout = old_stdout
+            sys.stderr = old_stderr
+            defaultmesaage = ""
+            with open(commit_msg_file) as f:
+                defaultmesaage = f.read()
+            with open(commit_msg_file, "w") as f:
+                f.write(m)
+                f.write(defaultmesaage)
+                out.success("Commit message is successful!")
+                return
+
         always_signoff: bool = self.config.settings["always_signoff"]
         signoff: bool = self.arguments.get("signoff")
-
         if signoff:
             out.warn(
                 "signoff mechanic is deprecated, please use `cz commit -- -s` instead."

docs/getting_started.md

@@ -95,12 +95,14 @@ repos:
       - id: commitizen
       - id: commitizen-branch
         stages: [push]
+      - id: commitizen-prepare-commit-msg
+        stages: [prepare-commit-msg]
 ```
 
 After the configuration is added, you'll need to run:
 
 ```sh
-pre-commit install --hook-type commit-msg --hook-type pre-push
+pre-commit install --hook-type commit-msg --hook-type pre-push --hook-type prepare-commit-msg
 ```
 
 If you aren't using both hooks, you needn't install both stages.
@@ -109,6 +111,7 @@ If you aren't using both hooks, you needn't install both stages.
 | ----------------- | ----------------- |
 | commitizen        | commit-msg        |
 | commitizen-branch | pre-push          |
+| commitizen-prepare-commit-msg | prepare-commit-msg |
 
 Note that pre-commit discourages using `master` as a revision, and the above command will print a warning. You should replace the `master` revision with the [latest tag](https://github.com/commitizen-tools/commitizen/tags). This can be done automatically with:
 

tests/commands/test_commit_command.py

@@ -525,3 +525,41 @@ def test_commit_command_shows_description_when_use_help_option(
 
     out, _ = capsys.readouterr()
     file_regression.check(out, extension=".txt")
+
+
+def test_commit_from_pre_commit_msg_hook(config, mocker, capsys):
+    testargs = ["cz", "commit", "--commit-msg-file", "some_file"]
+    mocker.patch.object(sys, "argv", testargs)
+
+    prompt_mock = mocker.patch("questionary.prompt")
+    prompt_mock.return_value = {
+        "prefix": "feat",
+        "subject": "user created",
+        "scope": "",
+        "is_breaking_change": False,
+        "body": "",
+        "footer": "",
+    }
+
+    commit_mock = mocker.patch("commitizen.git.commit")
+    mocker.patch("commitizen.commands.commit.WrapStdin")
+    mocker.patch("os.open")
+    reader_mock = mocker.mock_open(read_data="\n\n#test\n")
+    mocker.patch("builtins.open", reader_mock, create=True)
+
+    cli.main()
+
+    out, _ = capsys.readouterr()
+    assert "Commit message is successful!" in out
+    commit_mock.assert_not_called()
+
+
+def test_WrapStdin(mocker):
+    mocker.patch("os.open")
+    reader_mock = mocker.mock_open(read_data="data")
+    mocker.patch("builtins.open", reader_mock, create=True)
+
+    wrap_stdin = commands.commit.WrapStdin()
+
+    assert wrap_stdin.encoding == "UTF-8"
+    assert wrap_stdin.read() == "data"