fix(changelog): include latest change when dry run and incremental

Closes #1024

commitizen/commands/changelog.py

@@ -133,10 +133,6 @@ def write_changelog(
             if changelog_hook:
                 changelog_out = changelog_hook(changelog_out, partial_changelog)
 
-            if self.dry_run:
-                out.write(changelog_out)
-                raise DryRunExit()
-
             changelog_file.write(changelog_out)
 
     def export_template(self):
@@ -221,6 +217,14 @@ def __call__(self):
         )
         changelog_out = changelog_out.lstrip("\n")
 
+        # Dry_run is executed here to avoid checking and reading the files
+        if self.dry_run:
+            changelog_hook: Callable | None = self.cz.changelog_hook
+            if changelog_hook:
+                changelog_out = changelog_hook(changelog_out, "")
+            out.write(changelog_out)
+            raise DryRunExit()
+
         lines = []
         if self.incremental and os.path.isfile(self.file_name):
             with open(self.file_name, encoding=self.encoding) as changelog_file:

tests/commands/test_bump_command.py

@@ -1406,3 +1406,36 @@ def test_bump_template_extra_quotes(
 
     changelog = project_root / any_changelog_format.default_changelog_file
     assert changelog.read_text() == "no-quote - single quotes - double quotes"
+
+
+def test_bump_changelog_contains_increment_only(mocker, tmp_commitizen_project, capsys):
+    """Issue 1024"""
+    # Initialize commitizen up to v1.0.0
+    project_root = Path(tmp_commitizen_project)
+    tmp_commitizen_cfg_file = project_root / "pyproject.toml"
+    tmp_commitizen_cfg_file.write_text(
+        "[tool.commitizen]\n" 'version="1.0.0"\n' "update_changelog_on_bump = true\n"
+    )
+    tmp_changelog_file = project_root / "CHANGELOG.md"
+    tmp_changelog_file.write_text("## v1.0.0")
+    create_file_and_commit("feat(user): new file")
+    create_tag("v1.0.0")
+
+    # Add a commit and bump to v2.0.0
+    create_file_and_commit("feat(user)!: new file")
+    testargs = ["cz", "bump", "--yes"]
+    mocker.patch.object(sys, "argv", testargs)
+    cli.main()
+    _ = capsys.readouterr()
+
+    # Add a commit and create the incremental changelog to v3.0.0
+    # it should only include v3 changes
+    create_file_and_commit("feat(next)!: next version")
+    testargs = ["cz", "bump", "--yes", "--files-only", "--changelog-to-stdout"]
+    mocker.patch.object(sys, "argv", testargs)
+    with pytest.raises(ExpectedExit):
+        cli.main()
+    out, _ = capsys.readouterr()
+
+    assert "3.0.0" in out
+    assert "2.0.0" not in out

tests/commands/test_changelog_command.py

@@ -294,11 +294,15 @@ def test_changelog_hook(mocker: MockFixture, config: BaseConfig, dry_run: bool):
         changelog()
     except DryRunExit:
         pass
+
     full_changelog = (
         "## Unreleased\n\n### Refactor\n\n- is in changelog\n\n### Feat\n\n- new file\n"
     )
+    partial_changelog = full_changelog
+    if dry_run:
+        partial_changelog = ""
 
-    changelog_hook_mock.assert_called_with(full_changelog, full_changelog)
+    changelog_hook_mock.assert_called_with(full_changelog, partial_changelog)
 
 
 @pytest.mark.usefixtures("tmp_commitizen_project")