Merge pull request #561 from projectsyn/fix/package-update-commit

Don't create empty commits with `package update`

commodore/dependency_templater.py

@@ -4,6 +4,7 @@
 import re
 import tempfile
 import shutil
+import textwrap
 
 from abc import ABC, abstractmethod
 from pathlib import Path
@@ -158,11 +159,25 @@ def create(self) -> None:
             f"{self.deptype.capitalize()} {self.name} successfully added 🎉", bold=True
         )
 
-    def commit(self, msg: str, amend=False, init=True) -> None:
+    def commit(self, msg: str, amend=False, init=True) -> bool:
         # If we're amending an existing commit, we don't want to force initialize the
         # repo.
         repo = GitRepo(self.repo_url, self.target_dir, force_init=not amend and init)
 
-        repo.stage_all()
+        # stage_all() returns the full diff compared to the last commit. Therefore, we
+        # do stage_files() first and then stage_all(), to ensure we get the complete
+        # diff.
         repo.stage_files(self.additional_files)
-        repo.commit(msg, amend=amend)
+        diff_text, changed = repo.stage_all()
+
+        if changed:
+            indented = textwrap.indent(diff_text, "     ")
+            message = f" > Changes:\n{indented}"
+        else:
+            message = " > No changes."
+        click.echo(message)
+
+        if changed:
+            # Only create a new commmit if there are any changes.
+            repo.commit(msg, amend=amend)
+        return changed

commodore/package/template.py

@@ -157,12 +157,19 @@ def update(self):
             extra_context=self.cookiecutter_args,
         )
 
-        self.commit(
+        updated = self.commit(
             "Update from template\n\n"
             + f"Template version: {self.template_version} ({self.template_commit[:7]})",
             init=False,
         )
 
-        click.secho(
-            f"{self.deptype.capitalize()} {self.name} successfully updated 🎉", bold=True
-        )
+        if updated:
+            click.secho(
+                f"{self.deptype.capitalize()} {self.name} successfully updated 🎉",
+                bold=True,
+            )
+        else:
+            click.secho(
+                f"{self.deptype.capitalize()} {self.name} already up-to-date 🎉",
+                bold=True,
+            )

tests/test_package_template.py

@@ -248,6 +248,7 @@ def test_package_update_copyright_holder(
 @pytest.mark.parametrize(
     "initial_test_cases,additional_test_cases,remove_test_cases",
     (
+        ([], [], []),
         ([], ["foo"], []),
         (["foo"], ["bar"], ["foo"]),
         (["foo", "bar"], ["baz"], ["foo", "bar"]),
@@ -291,7 +292,10 @@ def test_package_update_test_cases(
     r = GitRepo(None, pkg_dir)
     assert not r.repo.is_dirty()
     assert len(r.repo.untracked_files) == 0
-    assert r.repo.head.commit.message.startswith("Update from template\n\n")
+    if additional_test_cases == [] and remove_test_cases == []:
+        assert r.repo.head.commit.message.startswith("Initial commit")
+    else:
+        assert r.repo.head.commit.message.startswith("Update from template\n\n")
 
 
 def test_package_templater_from_existing_nonexistent(tmp_path: Path, config: Config):