Also test validity and correctness of extruder definitions

This makes a few things slightly simpler as well since it now parameterises the tests with the entire path of the definition file so we don't have to reconstruct that in every test.

tests/Settings/TestDefinitionContainer.py

@@ -17,6 +17,10 @@ Resources.addSearchPath(os.path.abspath(os.path.join(os.path.dirname(__file__),
 
 
 machine_filepaths = sorted(os.listdir(os.path.join(os.path.dirname(__file__), "..", "..", "resources", "definitions")))
+machine_filepaths = [os.path.join(os.path.dirname(__file__), "..", "..", "resources", "definitions", filename) for filename in machine_filepaths]
+extruder_filepaths = sorted(os.listdir(os.path.join(os.path.dirname(__file__), "..", "..", "resources", "extruders")))
+extruder_filepaths = [os.path.join(os.path.dirname(__file__), "..", "..", "resources", "extruders", filename) for filename in extruder_filepaths]
+definition_filepaths = machine_filepaths + extruder_filepaths
 all_meshes = os.listdir(os.path.join(os.path.dirname(__file__), "..", "..", "resources", "meshes"))
 all_images = os.listdir(os.path.join(os.path.dirname(__file__), "..", "..", "resources", "images"))
 
@@ -29,17 +33,16 @@ def definition_container():
 
 
 ##  Tests all definition containers
-@pytest.mark.parametrize("file_name", machine_filepaths)
-def test_validateMachineDefinitionContainer(file_name, definition_container):
+@pytest.mark.parametrize("file_path", definition_filepaths)
+def test_validateMachineDefinitionContainer(file_path, definition_container):
+    file_name = os.path.basename(file_path)
     if file_name == "fdmprinter.def.json" or file_name == "fdmextruder.def.json":
         return  # Stop checking, these are root files.
 
-    definition_path = os.path.join(os.path.dirname(__file__), "..", "..", "resources", "definitions")
-    assertIsDefinitionValid(definition_container, definition_path, file_name)
+    assertIsDefinitionValid(definition_container, file_path)
 
-
-def assertIsDefinitionValid(definition_container, path, file_name):
-    with open(os.path.join(path, file_name), encoding = "utf-8") as data:
+def assertIsDefinitionValid(definition_container, file_path):
+    with open(file_path, encoding = "utf-8") as data:
         json = data.read()
         parser, is_valid = definition_container.readAndValidateSerialized(json)
         assert is_valid #The definition has invalid JSON structure.
@@ -57,10 +60,9 @@ def assertIsDefinitionValid(definition_container, path, file_name):
 #   When a definition container defines a "default_value" but inherits from a
 #   definition that defines a "value", the "default_value" is ineffective. This
 #   test fails on those things.
-@pytest.mark.parametrize("file_name", machine_filepaths)
-def test_validateOverridingDefaultValue(file_name: str):
-    definition_path = os.path.join(os.path.dirname(__file__), "..", "..", "resources", "definitions", file_name)
-    with open(definition_path, encoding = "utf-8") as f:
+@pytest.mark.parametrize("file_path", machine_filepaths)
+def test_validateOverridingDefaultValue(file_path: str):
+    with open(file_path, encoding = "utf-8") as f:
         doc = json.load(f)
 
     if "inherits" not in doc:
@@ -70,7 +72,7 @@ def test_validateOverridingDefaultValue(file_name: str):
     parent_settings = getInheritedSettings(doc["inherits"])
     for key, val in doc["overrides"].items():
         if "value" in parent_settings[key]:
-            assert "default_value" not in val, "Unnecessary default_value for {key} in {file_name}".format(key = key, file_name = file_name)  # If there is a value in the parent settings, then the default_value is not effective.
+            assert "default_value" not in val, "Unnecessary default_value for {key} in {file_name}".format(key = key, file_name = file_path)  # If there is a value in the parent settings, then the default_value is not effective.
 
 ##  Get all settings and their properties from a definition we're inheriting
 #   from.
@@ -130,10 +132,9 @@ def merge_dicts(base: Dict[str, Any], overrides: Dict[str, Any]) -> Dict[str, An
 #
 #   ID fields are legacy. They should not be used any more. This is legacy that
 #   people don't seem to be able to get used to.
-@pytest.mark.parametrize("file_name", machine_filepaths)
-def test_noId(file_name):
-    definition_path = os.path.join(os.path.dirname(__file__), "..", "..", "resources", "definitions", file_name)
-    with open(definition_path, encoding = "utf-8") as f:
+@pytest.mark.parametrize("file_path", machine_filepaths)
+def test_noId(file_path: str):
+    with open(file_path, encoding = "utf-8") as f:
         doc = json.load(f)
 
     assert "id" not in doc, "Definitions should not have an ID field."