refactor: overwrite always on updates

Updates not only overwrite files when actually updating, but also when applying the git diff.

Since only git-tracked subprojects can be updated, in reality there's no problem when overwriting. I find myself always overwriting and later fixing stuff with git tools.

BREAKING CHANGE: Updates will overwrite existing files always. If you need to select only some files, just use `git mergetool` or `git difftool` after updating.

BREAKING CHANGE: Flag `--overwrite/-w` disappeared from `copier update`. It is now implicit.

BREAKING CHANGE: To update via API, `overwrite=True` is now required.

Fix #741.

copier/cli.py

@@ -129,18 +129,6 @@ class _Subcommand(cli.Application):
         ),
     )
     pretend = cli.Flag(["-n", "--pretend"], help="Run but do not make any changes")
-    force = cli.Flag(
-        ["-f", "--force"],
-        help="Same as `--defaults --overwrite`.",
-    )
-    defaults = cli.Flag(
-        ["-l", "--defaults"],
-        help="Use default answers to questions, which might be null if not specified.",
-    )
-    overwrite = cli.Flag(
-        ["-w", "--overwrite"],
-        help="Overwrite files that already exist, without asking.",
-    )
     skip = cli.SwitchAttr(
         ["-s", "--skip"],
         str,
@@ -185,8 +173,6 @@ def _worker(self, src_path: OptStr = None, dst_path: str = ".", **kwargs) -> Wor
             dst_path=Path(dst_path),
             answers_file=self.answers_file,
             exclude=self.exclude,
-            defaults=self.force or self.defaults,
-            overwrite=self.force or self.overwrite,
             pretend=self.pretend,
             skip_if_exists=self.skip,
             quiet=self.quiet,
@@ -212,6 +198,18 @@ class CopierCopySubApp(_Subcommand):
         default=True,
         help="On error, do not delete destination if it was created by Copier.",
     )
+    defaults = cli.Flag(
+        ["-l", "--defaults"],
+        help="Use default answers to questions, which might be null if not specified.",
+    )
+    force = cli.Flag(
+        ["-f", "--force"],
+        help="Same as `--defaults --overwrite`.",
+    )
+    overwrite = cli.Flag(
+        ["-w", "--overwrite"],
+        help="Overwrite files that already exist, without asking.",
+    )
 
     @handle_exceptions
     def main(self, template_src: str, destination_path: str) -> int:
@@ -230,6 +228,8 @@ def main(self, template_src: str, destination_path: str) -> int:
             template_src,
             destination_path,
             cleanup_on_error=self.cleanup_on_error,
+            defaults=self.force or self.defaults,
+            overwrite=self.force or self.overwrite,
         ).run_copy()
         return 0
 
@@ -260,6 +260,19 @@ class CopierRecopySubApp(_Subcommand):
         """
     )
 
+    defaults = cli.Flag(
+        ["-l", "--defaults"],
+        help="Use default answers to questions, which might be null if not specified.",
+    )
+    force = cli.Flag(
+        ["-f", "--force"],
+        help="Same as `--defaults --overwrite`.",
+    )
+    overwrite = cli.Flag(
+        ["-w", "--overwrite"],
+        help="Overwrite files that already exist, without asking.",
+    )
+
     @handle_exceptions
     def main(self, destination_path: cli.ExistingDirectory = ".") -> int:
         """Call [run_recopy][copier.main.Worker.run_recopy].
@@ -274,6 +287,8 @@ def main(self, destination_path: cli.ExistingDirectory = ".") -> int:
         """
         self._worker(
             dst_path=destination_path,
+            defaults=self.force or self.defaults,
+            overwrite=self.force or self.overwrite,
         ).run_recopy()
         return 0
 
@@ -318,6 +333,10 @@ class CopierUpdateSubApp(_Subcommand):
             "accuracy, decrease for resilience."
         ),
     )
+    defaults = cli.Flag(
+        ["-l", "-f", "--defaults"],
+        help="Use default answers to questions, which might be null if not specified.",
+    )
 
     @handle_exceptions
     def main(self, destination_path: cli.ExistingDirectory = ".") -> int:
@@ -335,6 +354,8 @@ def main(self, destination_path: cli.ExistingDirectory = ".") -> int:
             dst_path=destination_path,
             conflict=self.conflict,
             context_lines=self.context_lines,
+            defaults=self.defaults,
+            overwrite=True,
         ).run_update()
         return 0
 

copier/main.py

@@ -755,6 +755,11 @@ def run_update(self) -> None:
                 f"Your are downgrading from {self.subproject.template.version} to {self.template.version}. "
                 "Downgrades are not supported."
             )
+        if not self.overwrite:
+            # Only git-tracked subprojects can be updated, so the user can
+            # review the diff before committing; so we can safely avoid
+            # asking for confirmation
+            raise UserMessageError("Enable overwrite to update a subproject.")
         if not self.quiet:
             # TODO Unify printing tools
             print(

tests/test_conditional_file_name.py

@@ -101,7 +101,7 @@ def test_answer_changes(
         git("commit", "-mv1")
 
     if interactive:
-        tui = spawn(COPIER_PATH + ("update", "--overwrite", str(dst)), timeout=10)
+        tui = spawn(COPIER_PATH + ("update", str(dst)), timeout=10)
         expect_prompt(tui, "condition", "bool")
         tui.expect_exact("(Y/n)")
         tui.sendline("n")

tests/test_updatediff.py

@@ -11,6 +11,7 @@
 from plumbum.cmd import git
 
 from copier.cli import CopierApp
+from copier.errors import UserMessageError
 from copier.main import Worker, run_copy, run_update
 from copier.types import Literal
 
@@ -201,7 +202,7 @@ def test_updatediff(tmp_path_factory: pytest.TempPathFactory) -> None:
         )
         commit("-m", "I prefer grog")
         # Update target to latest tag and check it's updated in answers file
-        CopierApp.run(["copier", "update", "--defaults", "--overwrite"], exit=False)
+        CopierApp.run(["copier", "update", "--defaults"], exit=False)
         assert answers.read_text() == dedent(
             f"""\
             # Changes here will be overwritten by Copier
@@ -223,7 +224,7 @@ def test_updatediff(tmp_path_factory: pytest.TempPathFactory) -> None:
         commit("-m", "Update template to v0.0.2")
         # Update target to latest commit, which is still untagged
         CopierApp.run(
-            ["copier", "update", "--defaults", "--overwrite", "--vcs-ref=HEAD"],
+            ["copier", "update", "--defaults", "--vcs-ref=HEAD"],
             exit=False,
         )
         # Check no new migrations were executed
@@ -258,7 +259,7 @@ def test_updatediff(tmp_path_factory: pytest.TempPathFactory) -> None:
         assert not git("status", "--porcelain")
         # No more updates exist, so updating again should change nothing
         CopierApp.run(
-            ["copier", "update", "--defaults", "--overwrite", "--vcs-ref=HEAD"],
+            ["copier", "update", "--defaults", "--vcs-ref=HEAD"],
             exit=False,
         )
         assert not git("status", "--porcelain")
@@ -575,7 +576,7 @@ def test_overwrite_answers_file_always(
         git("commit", "-m1")
         # When updating, the only thing to overwrite is the copier answers file,
         # which shouldn't ask, so also this shouldn't hang with overwrite=False
-        run_update(defaults=True, answers_file=answers_file)
+        run_update(defaults=True, overwrite=True, answers_file=answers_file)
     answers = yaml.safe_load(
         (dst / (answers_file or ".copier-answers.yml")).read_bytes()
     )
@@ -641,7 +642,11 @@ def test_file_removed(tmp_path_factory: pytest.TempPathFactory) -> None:
         git("tag", "2")
     # Subproject updates
     with local.cwd(dst):
-        run_update(conflict="rej")
+        with pytest.raises(
+            UserMessageError, match="Enable overwrite to update a subproject."
+        ):
+            run_update(conflict="rej")
+        run_update(conflict="rej", overwrite=True)
     # Check what must still exist
     assert (dst / ".copier-answers.yml").is_file()
     assert (dst / "I.txt").is_file()
@@ -730,7 +735,7 @@ def test_update_inline_changed_answers_and_questions(
         git("commit", "-am2")
         # Update from template, inline, with answer changes
         if interactive:
-            tui = spawn(COPIER_PATH + ("update", "-w", "--conflict=inline"), timeout=10)
+            tui = spawn(COPIER_PATH + ("update", "--conflict=inline"), timeout=10)
             tui.expect_exact("b (bool)")
             tui.expect_exact("(Y/n)")
             tui.sendline()
@@ -941,7 +946,6 @@ def function_two():
     else:
         COPIER_CMD(
             "update",
-            "--overwrite",
             str(dst),
             "--conflict=inline",
             f"--context-lines={context_lines}",