Major fixes and new features

venv/lib/python3.12/site-packages/mypy/test/testgraph.py

@@ -0,0 +1,83 @@
+"""Test cases for graph processing code in build.py."""
+
+from __future__ import annotations
+
+import sys
+from typing import AbstractSet
+
+from mypy.build import BuildManager, BuildSourceSet, State, order_ascc, sorted_components
+from mypy.errors import Errors
+from mypy.fscache import FileSystemCache
+from mypy.graph_utils import strongly_connected_components, topsort
+from mypy.modulefinder import SearchPaths
+from mypy.options import Options
+from mypy.plugin import Plugin
+from mypy.report import Reports
+from mypy.test.helpers import Suite, assert_equal
+from mypy.version import __version__
+
+
+class GraphSuite(Suite):
+    def test_topsort(self) -> None:
+        a = frozenset({"A"})
+        b = frozenset({"B"})
+        c = frozenset({"C"})
+        d = frozenset({"D"})
+        data: dict[AbstractSet[str], set[AbstractSet[str]]] = {a: {b, c}, b: {d}, c: {d}}
+        res = list(topsort(data))
+        assert_equal(res, [{d}, {b, c}, {a}])
+
+    def test_scc(self) -> None:
+        vertices = {"A", "B", "C", "D"}
+        edges: dict[str, list[str]] = {"A": ["B", "C"], "B": ["C"], "C": ["B", "D"], "D": []}
+        sccs = {frozenset(x) for x in strongly_connected_components(vertices, edges)}
+        assert_equal(sccs, {frozenset({"A"}), frozenset({"B", "C"}), frozenset({"D"})})
+
+    def _make_manager(self) -> BuildManager:
+        options = Options()
+        options.use_builtins_fixtures = True
+        errors = Errors(options)
+        fscache = FileSystemCache()
+        search_paths = SearchPaths((), (), (), ())
+        manager = BuildManager(
+            data_dir="",
+            search_paths=search_paths,
+            ignore_prefix="",
+            source_set=BuildSourceSet([]),
+            reports=Reports("", {}),
+            options=options,
+            version_id=__version__,
+            plugin=Plugin(options),
+            plugins_snapshot={},
+            errors=errors,
+            flush_errors=lambda msgs, serious: None,
+            fscache=fscache,
+            stdout=sys.stdout,
+            stderr=sys.stderr,
+        )
+        return manager
+
+    def test_sorted_components(self) -> None:
+        manager = self._make_manager()
+        graph = {
+            "a": State("a", None, "import b, c", manager),
+            "d": State("d", None, "pass", manager),
+            "b": State("b", None, "import c", manager),
+            "c": State("c", None, "import b, d", manager),
+        }
+        res = sorted_components(graph)
+        assert_equal(res, [frozenset({"d"}), frozenset({"c", "b"}), frozenset({"a"})])
+
+    def test_order_ascc(self) -> None:
+        manager = self._make_manager()
+        graph = {
+            "a": State("a", None, "import b, c", manager),
+            "d": State("d", None, "def f(): import a", manager),
+            "b": State("b", None, "import c", manager),
+            "c": State("c", None, "import b, d", manager),
+        }
+        res = sorted_components(graph)
+        assert_equal(res, [frozenset({"a", "d", "c", "b"})])
+        ascc = res[0]
+        scc = order_ascc(graph, ascc)
+        assert_equal(scc, ["d", "c", "b", "a"])