_workspaces.py: Increment format version, drop support for old versions

Do not accept old versions as bst 1.x workspaces do not separate source
and build files.

2 files changed, 13 insertions, 81 deletions

diff --git a/src/buildstream/_workspaces.py b/src/buildstream/_workspaces.py
index 5c3b4af8f..edc0564c5 100644
--- a/src/buildstream/_workspaces.py
+++ b/src/buildstream/_workspaces.py
@@ -21,12 +21,11 @@ import os
 from . import utils
 from . import _yaml
 
-from .node import MappingNode, ScalarNode
 from ._exceptions import LoadError
 from .exceptions import LoadErrorReason
 
 
-BST_WORKSPACE_FORMAT_VERSION = 3
+BST_WORKSPACE_FORMAT_VERSION = 4
 BST_WORKSPACE_PROJECT_FORMAT_VERSION = 1
 WORKSPACE_PROJECT_FILE = ".bstproject.yaml"
 
@@ -526,38 +525,17 @@ class Workspaces:
                 "Format version is not an integer in workspace configuration", LoadErrorReason.INVALID_DATA
             )
 
-        if version == 0:
-            # Pre-versioning format can be of two forms
-            for element, config in workspaces.items():
-                config_type = type(config)
-
-                if config_type is ScalarNode:
-                    pass
-
-                elif config_type is MappingNode:
-                    sources = list(config.values())
-                    if len(sources) > 1:
-                        detail = (
-                            "There are multiple workspaces open for '{}'.\n"
-                            + "This is not supported anymore.\n"
-                            + "Please remove this element from '{}'."
-                        )
-                        raise LoadError(detail.format(element, self._get_filename()), LoadErrorReason.INVALID_DATA)
-
-                    workspaces[element] = sources[0]
-
-                else:
-                    raise LoadError("Workspace config is in unexpected format.", LoadErrorReason.INVALID_DATA)
-
-            res = {
-                element: Workspace(self._toplevel_project, path=config.as_str())
-                for element, config in workspaces.items()
-            }
+        if version < 4:
+            # bst 1.x workspaces do not separate source and build files.
+            raise LoadError(
+                "Workspace configuration format version {} not supported."
+                "Please recreate this workspace.".format(version),
+                LoadErrorReason.INVALID_DATA,
+            )
 
-        elif 1 <= version <= BST_WORKSPACE_FORMAT_VERSION:
+        if 4 <= version <= BST_WORKSPACE_FORMAT_VERSION:
             workspaces = workspaces.get_mapping("workspaces", default={})
             res = {element: self._load_workspace(node) for element, node in workspaces.items()}
-
         else:
             raise LoadError(
                 "Workspace configuration format version {} not supported."
diff --git a/tests/frontend/workspace.py b/tests/frontend/workspace.py
index e05b6bd1f..5b3ec7b7c 100644
--- a/tests/frontend/workspace.py
+++ b/tests/frontend/workspace.py
@@ -821,6 +821,8 @@ def test_detect_modifications(cli, tmpdir, datafiles, modification, strict):
         {"format-version": 0, "alpha.bst": {0: "/workspaces/bravo", 1: "/workspaces/charlie",}},
         # Test loading a version with decimals
         {"format-version": 0.5},
+        # Test loading an unsupported old version
+        {"format-version": 3},
         # Test loading a future version
         {"format-version": BST_WORKSPACE_FORMAT_VERSION + 1},
     ],
@@ -842,58 +844,10 @@ def test_list_unsupported_workspace(cli, datafiles, workspace_cfg):
 @pytest.mark.parametrize(
     "workspace_cfg,expected",
     [
-        # Test loading version 0 without a dict
+        # Test loading version 4
         (
-            {"alpha.bst": "/workspaces/bravo"},
             {
-                "format-version": BST_WORKSPACE_FORMAT_VERSION,
-                "workspaces": {"alpha.bst": {"prepared": False, "path": "/workspaces/bravo", "running_files": {}}},
-            },
-        ),
-        # Test loading version 0 with only one source
-        (
-            {"alpha.bst": {0: "/workspaces/bravo"}},
-            {
-                "format-version": BST_WORKSPACE_FORMAT_VERSION,
-                "workspaces": {"alpha.bst": {"prepared": False, "path": "/workspaces/bravo", "running_files": {}}},
-            },
-        ),
-        # Test loading version 1
-        (
-            {"format-version": 1, "workspaces": {"alpha.bst": {"path": "/workspaces/bravo"}}},
-            {
-                "format-version": BST_WORKSPACE_FORMAT_VERSION,
-                "workspaces": {"alpha.bst": {"prepared": False, "path": "/workspaces/bravo", "running_files": {}}},
-            },
-        ),
-        # Test loading version 2
-        (
-            {
-                "format-version": 2,
-                "workspaces": {
-                    "alpha.bst": {
-                        "path": "/workspaces/bravo",
-                        "last_successful": "some_key",
-                        "running_files": {"beta.bst": ["some_file"]},
-                    }
-                },
-            },
-            {
-                "format-version": BST_WORKSPACE_FORMAT_VERSION,
-                "workspaces": {
-                    "alpha.bst": {
-                        "prepared": False,
-                        "path": "/workspaces/bravo",
-                        "last_successful": "some_key",
-                        "running_files": {"beta.bst": ["some_file"]},
-                    }
-                },
-            },
-        ),
-        # Test loading version 3
-        (
-            {
-                "format-version": 3,
+                "format-version": 4,
                 "workspaces": {"alpha.bst": {"prepared": True, "path": "/workspaces/bravo", "running_files": {}}},
             },
             {