implement support for local extensions

cruft/_commands/check.py

@@ -17,7 +17,7 @@ def check(
     used to generate this project."""
     cruft_file = utils.cruft.get_cruft_file(project_dir)
     cruft_state = json.loads(cruft_file.read_text())
-    with AltTemporaryDirectory() as cookiecutter_template_dir:
+    with AltTemporaryDirectory(cruft_state.get("directory")) as cookiecutter_template_dir:
         with utils.cookiecutter.get_cookiecutter_repo(
             cruft_state["template"],
             Path(cookiecutter_template_dir),

cruft/_commands/create.py

@@ -23,7 +23,7 @@ def create(
 ) -> Path:
     """Expand a Git based Cookiecutter template into a new project on disk."""
     template_git_url = utils.cookiecutter.resolve_template_url(template_git_url)
-    with AltTemporaryDirectory() as cookiecutter_template_dir_str:
+    with AltTemporaryDirectory(directory) as cookiecutter_template_dir_str:
         cookiecutter_template_dir = Path(cookiecutter_template_dir_str)
         with utils.cookiecutter.get_cookiecutter_repo(
             template_git_url, cookiecutter_template_dir, checkout

cruft/_commands/diff.py

@@ -19,7 +19,7 @@ def diff(
     checkout = checkout or cruft_state.get("commit")
 
     has_diff = False
-    with AltTemporaryDirectory() as tmpdir_:
+    with AltTemporaryDirectory(cruft_state.get("directory")) as tmpdir_:
         tmpdir = Path(tmpdir_)
         repo_dir = tmpdir / "repo"
         remote_template_dir = tmpdir / "remote"

cruft/_commands/link.py

@@ -22,7 +22,7 @@ def link(
     """Links an existing project created from a template, to the template it was created from."""
     cruft_file = utils.cruft.get_cruft_file(project_dir, exists=False)
     template_git_url = utils.cookiecutter.resolve_template_url(template_git_url)
-    with AltTemporaryDirectory() as cookiecutter_template_dir_str:
+    with AltTemporaryDirectory(directory) as cookiecutter_template_dir_str:
         cookiecutter_template_dir = Path(cookiecutter_template_dir_str)
         with utils.cookiecutter.get_cookiecutter_repo(
             template_git_url, cookiecutter_template_dir, checkout

cruft/_commands/update.py

@@ -38,7 +38,13 @@ def update(
 
     cruft_state = json.loads(cruft_file.read_text())
 
-    with AltTemporaryDirectory() as tmpdir_:
+    directory = cruft_state.get("directory", "")
+    if directory:
+        directory = str(Path("repo") / directory)
+    else:
+        directory = "repo"
+
+    with AltTemporaryDirectory(directory) as tmpdir_:
         # Initial setup
         tmpdir = Path(tmpdir_)
         repo_dir = tmpdir / "repo"

cruft/_commands/utils/generate.py

@@ -85,7 +85,7 @@ def _generate_output(
     # Therefore we have to move the directory content to the expected output_dir.
     # See https://github.com/cookiecutter/cookiecutter/pull/907
     output_dir.mkdir(parents=True, exist_ok=True)
-    with AltTemporaryDirectory() as tmpdir:
+    with AltTemporaryDirectory(cruft_state.get("directory")) as tmpdir:
 
         # Kindly ask cookiecutter to generate the template
         template_dir = generate_files(

cruft/_commands/utils/iohelper.py

@@ -1,15 +1,28 @@
+import sys
+from pathlib import Path
 from tempfile import TemporaryDirectory
 from time import sleep
+from typing import Optional
 
 
 class AltTemporaryDirectory:
-    def __init__(self):
+    def __init__(self, directory: Optional[str] = None):
         self.tmpdir = TemporaryDirectory()
+        self._extended_path = False
+        self._directory = directory or ""
+        name = str(Path(self.tmpdir.name) / self._directory)
+        if name not in sys.path:
+            self._extended_path = True
+            sys.path.append(name)
 
     def __enter__(self):
         return self.tmpdir.name
 
     def cleanup(self, cnt=0):
+        if self._extended_path:
+            name = str(Path(self.tmpdir.name) / self._directory)
+            if name in sys.path:
+                sys.path.remove(name)
         if cnt >= 5:  # pragma: no cover
             raise RuntimeError("Could not delete TemporaryDirectory!")
         try:

tests/test_cli.py

@@ -471,3 +471,38 @@ def test_diff_skip_git_dir(args, expected_exit_code, cruft_runner, cookiecutter_
     print(result.stdout)
     assert result.exit_code == expected_exit_code
     assert ".git" not in result.stdout
+
+
+def test_local_extension(cruft_runner, tmpdir):
+    result = cruft_runner(
+        [
+            "create",
+            "--output-dir",
+            str(tmpdir),
+            "https://github.com/cruft/cookiecutter-test",
+            "--directory",
+            "dir",
+            "--checkout",
+            "extensions",
+            "-y",
+        ]
+    )
+    assert result.exit_code == 0
+    assert result.stdout == ""
+
+
+def test_local_extension_update(cruft_runner, tmpdir):
+    test_local_extension(cruft_runner, tmpdir)
+    result = cruft_runner(
+        [
+            "update",
+            "--project-dir",
+            str(tmpdir / "test"),
+            "--checkout",
+            "extensions-update",
+            "--skip-apply-ask",
+        ]
+    )
+    assert result.exit_code == 0
+    with open(tmpdir / "test" / "README.md") as f:
+        assert "Updated11" in f.read()