fix: make workspace reset accept either --all or elements list

src/buildstream/_frontend/cli.py

@@ -1211,15 +1211,22 @@ def workspace_close(app, remove_dir, all_, elements):
     is_flag=True,
     help="Mark workspace to re-execute configuration steps (if any) on next build. Does not alter workspace contents.",
 )
-@click.option("--all", "-a", "all_", is_flag=True, help="Reset all open workspaces")
+@click.option("--all", "-a", "all_", is_flag=True, help="Reset all open workspaces. Cannot be combined with ELEMENTS.")
 @click.argument("elements", nargs=-1, type=click.Path(readable=False))
 @click.pass_obj
 def workspace_reset(app, soft, all_, elements):
-    """Reset a workspace to its original state"""
+    """Reset a workspace to its original state.
+
+    Specify either one or more ELEMENTS, or use -a to target all
+    workspaces at once. These options are mutually exclusive.
+    """
 
     # Check that the workspaces in question exist
     with app.initialized():
 
+        if all_ and elements:
+            raise AppError("Specify either --all or elements, not both")
+
         if not (all_ or elements):
             element = app.stream.get_default_target()
             if element:

tests/frontend/workspace.py

@@ -634,6 +634,49 @@ def test_reset_all(cli, tmpdir, datafiles):
     assert not os.path.exists(os.path.join(workspace_beta, "etc", "pony.conf"))
 
 
+@pytest.mark.datafiles(DATA_DIR)
+def test_reset_all_with_elements_error(cli, tmpdir, datafiles):
+    # Open a workspace
+    tmpdir_alpha = os.path.join(str(tmpdir), "alpha")
+    element_name, project, workspace = open_workspace(cli, tmpdir_alpha, datafiles, "tar", suffix="-alpha")
+
+    # Modify workspace
+    shutil.rmtree(os.path.join(workspace, "usr", "bin"))
+    os.makedirs(os.path.join(workspace, "etc"))
+    with open(os.path.join(workspace, "etc", "pony.conf"), "w", encoding="utf-8") as f:
+        f.write("PONY='pink'")
+
+    # Reset with --all and elements should fail
+    result = cli.run(project=project, args=["workspace", "reset", "--all", element_name])
+    result.assert_main_error(ErrorDomain.APP, None)
+
+    # Verify workspace content was NOT modified
+    assert not os.path.exists(os.path.join(workspace, "usr", "bin", "hello"))
+    assert os.path.exists(os.path.join(workspace, "etc", "pony.conf"))
+
+
+@pytest.mark.datafiles(DATA_DIR)
+def test_reset_en_dash_soft_all_error(cli, tmpdir, datafiles):
+    # Open a workspace
+    tmpdir_alpha = os.path.join(str(tmpdir), "alpha")
+    element_name, project, workspace = open_workspace(cli, tmpdir_alpha, datafiles, "tar", suffix="-alpha")
+
+    # Modify workspace
+    shutil.rmtree(os.path.join(workspace, "usr", "bin"))
+    os.makedirs(os.path.join(workspace, "etc"))
+    with open(os.path.join(workspace, "etc", "pony.conf"), "w", encoding="utf-8") as f:
+        f.write("PONY='pink'")
+
+    # Reset with en-dash-soft (copy-pasted from docs) should be treated as element
+    # and combined with --all should error
+    result = cli.run(project=project, args=["workspace", "reset", "\u2013-soft", "--all"])
+    result.assert_main_error(ErrorDomain.APP, None)
+
+    # Verify workspace content was NOT modified
+    assert not os.path.exists(os.path.join(workspace, "usr", "bin", "hello"))
+    assert os.path.exists(os.path.join(workspace, "etc", "pony.conf"))
+
+
 @pytest.mark.datafiles(DATA_DIR)
 def test_list(cli, tmpdir, datafiles):
     element_name, project, workspace = open_workspace(cli, tmpdir, datafiles, "tar")