generator: add support for "graph_config" verifications (#802)

Author: jcristau

src/taskgraph/generator.py

@@ -378,6 +378,7 @@ def _run(self):
 
         # Initial verifications that don't depend on any generation state.
         self.verify("initial")
+        self.verify("graph_config", graph_config)
 
         if callable(self._parameters):
             parameters = self._parameters(graph_config)

src/taskgraph/util/verify.py

@@ -36,6 +36,12 @@ def verify(self):
         self.func()
 
 
+@dataclass(frozen=True)
+class GraphConfigVerification(Verification):
+    def verify(self, graph_config: GraphConfig):
+        self.func(graph_config)
+
+
 @dataclass(frozen=True)
 class GraphVerification(Verification):
     """Verification for a TaskGraph object."""
@@ -95,6 +101,7 @@ class VerificationSequence:
     _verifications: dict = field(default_factory=dict)
     _verification_types = {
         "graph": GraphVerification,
+        "graph_config": GraphConfigVerification,
         "initial": InitialVerification,
         "kinds": KindsVerification,
         "parameters": ParametersVerification,

test/test_generator.py

@@ -175,7 +175,7 @@ def test_verifications(mocker, maketgg):
     m = mocker.patch.object(generator, "verifications")
     tgg = maketgg(["_fake-t-2"], enable_verifications=True)
     tgg.morphed_task_graph
-    assert m.call_count == 9
+    assert m.call_count == 10
 
     m = mocker.patch.object(generator, "verifications")
     tgg = maketgg(["_fake-t-2"], enable_verifications=False)

test/test_util_verify.py

@@ -11,6 +11,7 @@
 from taskgraph.task import Task
 from taskgraph.util.treeherder import split_symbol
 from taskgraph.util.verify import (
+    GraphConfigVerification,
     GraphVerification,
     ParametersVerification,
     VerificationSequence,
@@ -38,6 +39,8 @@ def inner(name, **kwargs):
 
         if isinstance(v, GraphVerification):
             assert "graph" in kwargs
+
+        if isinstance(v, (GraphVerification, GraphConfigVerification)):
             kwargs.setdefault("graph_config", graph_config)
 
         if isinstance(v, (GraphVerification, ParametersVerification)):
@@ -94,6 +97,13 @@ def assert_simple_verification(arg):
             1,
             id="ParametersVerification",
         ),
+        pytest.param(
+            "graph_config",
+            ("passed-thru",),
+            assert_simple_verification,
+            1,
+            id="GraphConfigVerification",
+        ),
     ),
 )
 def test_verification_types(name, input, run_assertions, expected_called):