Report failed action names on dispatch failure

src/dotbot/cli.py

@@ -131,7 +131,8 @@ def main() -> None:
         if success:
             log.info("All tasks executed successfully")
         else:
-            msg = "Some tasks were not executed successfully"
+            failed_str = ", ".join(dispatcher.get_failed_actions())
+            msg = f"Some tasks were not executed successfully: {failed_str}"
             raise DispatchError(msg)  # noqa: TRY301
     except (ReadingError, DispatchError) as e:
         log.error(str(e))  # noqa: TRY400

src/dotbot/dispatcher.py

@@ -49,6 +49,7 @@ def _setup_context(
 
     def dispatch(self, tasks: List[Dict[str, Any]]) -> bool:
         success = True
+        self._failed_actions: List[str] = []
         for task in tasks:
             for action in task:
                 if (
@@ -77,6 +78,7 @@ def dispatch(self, tasks: List[Dict[str, Any]]) -> bool:
                             success = False
                     if not success:
                         self._log.error("Some plugins could not be loaded")
+                        self._failed_actions.append(action)
                         if self._exit:
                             self._log.error("Action plugins failed")
                             return False
@@ -90,26 +92,34 @@ def dispatch(self, tasks: List[Dict[str, Any]]) -> bool:
                             continue
                         try:
                             local_success = plugin.handle(action, task[action])
-                            if not local_success and self._exit:
-                                # The action has failed, exit
-                                self._log.error(f"Action {action} failed")
-                                return False
+                            if not local_success:
+                                self._failed_actions.append(action)
+                                if self._exit:
+                                    # The action has failed, exit
+                                    self._log.error(f"Action {action} failed")
+                                    return False
                             success &= local_success
                             handled = True
                         except Exception as err:  # noqa: BLE001
                             self._log.error(f"An error was encountered while executing action {action}")
                             self._log.debug(str(err))
+                            self._failed_actions.append(action)
                             if self._exit:
                                 # There was an exception, exit
                                 return False
                 if not handled:
                     success = False
+                    self._failed_actions.append(action)
                     self._log.error(f"Action {action} not handled")
                     if self._exit:
                         # Invalid action exit
                         return False
         return success
 
+    def get_failed_actions(self) -> List[str]:
+        """Return the list of action names that failed during the last dispatch."""
+        return self._failed_actions
+
 
 class DispatchError(Exception):
     pass

tests/dotbot_plugin_raises.py

@@ -0,0 +1,16 @@
+from typing import Any
+
+import dotbot
+
+
+class Raises(dotbot.Plugin):
+    def can_handle(self, directive: str) -> bool:
+        return directive == "plugin_raises"
+
+    def handle(self, directive: str, data: Any) -> bool:
+        _ = data
+        if directive != "plugin_raises":
+            msg = f"Raises cannot handle directive {directive}"
+            raise ValueError(msg)
+        msg = "test exception"
+        raise RuntimeError(msg)

tests/test_cli.py

@@ -25,8 +25,9 @@ def test_except_create(
     run_dotbot("--except", "create")
 
     assert not os.path.exists(os.path.join(home, "a"))
-    stdout = capfd.readouterr().out.splitlines()
-    assert any(line.startswith("success") for line in stdout)
+    stdout = capfd.readouterr().out
+    assert any(line.startswith("success") for line in stdout.splitlines())
+    assert "Some tasks were not executed successfully" not in stdout
 
 
 def test_except_shell(
@@ -73,7 +74,9 @@ def test_except_multiples(
     assert not any(line.startswith("failure") for line in stdout)
 
 
-def test_exit_on_failure(home: str, dotfiles: Dotfiles, run_dotbot: Callable[..., None]) -> None:
+def test_exit_on_failure(
+    capfd: pytest.CaptureFixture[str], home: str, dotfiles: Dotfiles, run_dotbot: Callable[..., None]
+) -> None:
     """Verify that processing can halt immediately on failures."""
 
     dotfiles.write_config(
@@ -89,6 +92,44 @@ def test_exit_on_failure(home: str, dotfiles: Dotfiles, run_dotbot: Callable[...
     assert os.path.isdir(os.path.join(home, "a"))
     assert not os.path.isdir(os.path.join(home, "b"))
 
+    stdout = capfd.readouterr().out
+    assert "Some tasks were not executed successfully: shell" in stdout
+
+
+def test_exit_on_failure_reports_multiple(
+    capfd: pytest.CaptureFixture[str], home: str, dotfiles: Dotfiles, run_dotbot: Callable[..., None]
+) -> None:
+    """Verify that multiple failed action names are reported."""
+
+    _ = home
+    dotfiles.write_config(
+        [
+            {"shell": ["this_is_not_a_command"]},
+            {"link": {"~/.f": "nonexistent_source"}},
+        ]
+    )
+    with pytest.raises(SystemExit):
+        run_dotbot()
+
+    stdout = capfd.readouterr().out
+    assert "Some tasks were not executed successfully: shell, link" in stdout
+
+
+def test_exit_on_failure_reports_exception(
+    capfd: pytest.CaptureFixture[str], home: str, dotfiles: Dotfiles, run_dotbot: Callable[..., None]
+) -> None:
+    """Verify that an action whose plugin raises an exception is reported as failed."""
+
+    _ = home
+    plugin_file = os.path.join(os.path.dirname(os.path.abspath(__file__)), "dotbot_plugin_raises.py")
+    shutil.copy(plugin_file, os.path.join(dotfiles.directory, "raises.py"))
+    dotfiles.write_config([{"plugin_raises": "~"}])
+    with pytest.raises(SystemExit):
+        run_dotbot("--plugin", os.path.join(dotfiles.directory, "raises.py"))
+
+    stdout = capfd.readouterr().out
+    assert "Some tasks were not executed successfully: plugin_raises" in stdout
+
 
 def test_only(
     capfd: pytest.CaptureFixture[str], home: str, dotfiles: Dotfiles, run_dotbot: Callable[..., None]