refactor(init): extract _read_pre_commit_config

Author: bearomorphism

commitizen/commands/init.py

@@ -2,6 +2,7 @@
 
 import os
 import shutil
+from typing import Any
 
 import questionary
 import yaml
@@ -73,6 +74,8 @@ def is_pre_commit_installed(self) -> bool:
 
 
 class Init:
+    _PRE_COMMIT_CONFIG_FILENAME = ".pre-commit-config.yaml"
+
     def __init__(self, config: BaseConfig, *args):
         self.config: BaseConfig = config
         self.encoding = config.settings["encoding"]
@@ -322,7 +325,20 @@ def _install_pre_commit_hook(self, hook_types: list[str] | None):
         if not hook_types:
             return
 
-        PRE_COMMIT_CONFIG_FILENAME = ".pre-commit-config.yaml"
+        config_data = self._read_pre_commit_config()
+
+        with smart_open(
+            self._PRE_COMMIT_CONFIG_FILENAME, "w", encoding=self.encoding
+        ) as config_file:
+            yaml.safe_dump(config_data, stream=config_file)
+
+        if not self.project_info.is_pre_commit_installed:
+            raise InitFailedError("pre-commit is not installed in current environment.")
+
+        self._exec_install_pre_commit_hook(hook_types)
+        out.write("commitizen pre-commit hook is now installed in your '.git'\n")
+
+    def _read_pre_commit_config(self) -> dict[Any, Any]:
         CZ_HOOK_CONFIG = {
             "repo": "https://github.com/commitizen-tools/commitizen",
             "rev": f"v{__version__}",
@@ -332,33 +348,28 @@ def _install_pre_commit_hook(self, hook_types: list[str] | None):
             ],
         }
 
-        config_data = {}
-        if self.project_info.has_pre_commit_config:
-            with open(
-                PRE_COMMIT_CONFIG_FILENAME, encoding=self.encoding
-            ) as config_file:
-                if yaml_data := yaml.safe_load(config_file):
-                    config_data = yaml_data
-
-            if repos := config_data.get("repos"):
-                for pre_commit_hook in repos:
-                    if "commitizen" in pre_commit_hook["repo"]:
-                        out.write("commitizen already in pre-commit config")
-                        break
-                else:
-                    repos.append(CZ_HOOK_CONFIG)
-        config_data.setdefault("repos", [CZ_HOOK_CONFIG])
+        DEFAULT_CONFIG = {"repos": [CZ_HOOK_CONFIG]}
 
-        with smart_open(
-            PRE_COMMIT_CONFIG_FILENAME, "w", encoding=self.encoding
+        if not self.project_info.has_pre_commit_config:
+            return DEFAULT_CONFIG
+
+        with open(
+            self._PRE_COMMIT_CONFIG_FILENAME, encoding=self.encoding
         ) as config_file:
-            yaml.safe_dump(config_data, stream=config_file)
+            config_data = yaml.safe_load(config_file)
+            if not isinstance(config_data, dict):
+                return DEFAULT_CONFIG
 
-        if not self.project_info.is_pre_commit_installed:
-            raise InitFailedError("pre-commit is not installed in current environment.")
+            repos = config_data.get("repos")
+            if not repos:
+                return DEFAULT_CONFIG
 
-        self._exec_install_pre_commit_hook(hook_types)
-        out.write("commitizen pre-commit hook is now installed in your '.git'\n")
+            if any("commitizen" in hook["repo"] for hook in repos):
+                out.write("commitizen already in pre-commit config")
+            else:
+                config_data["repos"].append(CZ_HOOK_CONFIG)
+
+            return config_data
 
     def _update_config_file(
         self, version_provider: str, version: VersionScheme, **kwargs