Clarify that graph JSON is required only for graph executor

Plus other clean ups

python/tvm/driver/tvmc/model.py

@@ -336,10 +336,8 @@ def import_package(self, package_path: str):
             with open(temp.relpath("metadata.json")) as metadata_json:
                 metadata = json.load(metadata_json)
 
-            if "graph" in metadata["runtimes"]:
-                graph = temp.relpath("runtime-config/graph/graph.json")
-            else:
-                graph = None
+            is_graph_runtime = "graph" in metadata["runtimes"]
+            graph = temp.relpath("runtime-config/graph/graph.json") if is_graph_runtime else None
             params = temp.relpath("parameters/default.params")
 
             self.type = "mlf"

tests/python/driver/tvmc/conftest.py

@@ -149,7 +149,7 @@ def onnx_mnist():
 
 
 @pytest.fixture
-def tflite_tvmc_compiler(tmpdir_factory):
+def tflite_compile_model(tmpdir_factory):
     """Support function that returns a TFLite compiled module"""
 
     def model_compiler(model_file, **overrides):

tests/python/driver/tvmc/test_mlf.py

@@ -85,10 +85,10 @@ def test_tvmc_export_package_mlf(tflite_mobilenet_v1_1_quant, tmpdir_factory):
     assert str(exp.value) == expected_reason, on_error
 
 
-def test_tvmc_import_package_mlf(tflite_mobilenet_v1_1_quant, tflite_tvmc_compiler):
+def test_tvmc_import_package_mlf_graph(tflite_mobilenet_v1_1_quant, tflite_compile_model):
     pytest.importorskip("tflite")
 
-    tflite_compiled_model_mlf = tflite_tvmc_compiler(
+    tflite_compiled_model_mlf = tflite_compile_model(
         tflite_mobilenet_v1_1_quant, output_format="mlf"
     )
 
@@ -101,15 +101,17 @@ def test_tvmc_import_package_mlf(tflite_mobilenet_v1_1_quant, tflite_tvmc_compil
 
     assert tvmc_package.lib_name is None, ".lib_name must not be set in the MLF archive."
     assert tvmc_package.lib_path is None, ".lib_path must not be set in the MLF archive."
-    assert tvmc_package.graph is not None, ".graph must be set in the MLF archive."
+    assert (
+        tvmc_package.graph is not None
+    ), ".graph must be set in the MLF archive for Graph executor."
     assert tvmc_package.params is not None, ".params must be set in the MLF archive."
     assert tvmc_package.type == "mlf", ".type must be set to 'mlf' in the MLF format."
 
 
-def test_tvmc_import_package_mlf_aot(tflite_mobilenet_v1_1_quant, tflite_tvmc_compiler):
+def test_tvmc_import_package_mlf_aot(tflite_mobilenet_v1_1_quant, tflite_compile_model):
     pytest.importorskip("tflite")
 
-    tflite_compiled_model_mlf = tflite_tvmc_compiler(
+    tflite_compiled_model_mlf = tflite_compile_model(
         tflite_mobilenet_v1_1_quant,
         target="c --executor=aot",
         output_format="mlf",
@@ -125,6 +127,6 @@ def test_tvmc_import_package_mlf_aot(tflite_mobilenet_v1_1_quant, tflite_tvmc_co
 
     assert tvmc_package.lib_name is None, ".lib_name must not be set in the MLF archive."
     assert tvmc_package.lib_path is None, ".lib_path must not be set in the MLF archive."
-    assert tvmc_package.graph is None, ".graph must not be set in the MLF archive for AOT."
+    assert tvmc_package.graph is None, ".graph must not be set in the MLF archive for AOT executor."
     assert tvmc_package.params is not None, ".params must be set in the MLF archive."
     assert tvmc_package.type == "mlf", ".type must be set to 'mlf' in the MLF format."

tests/python/driver/tvmc/test_runner.py

@@ -72,14 +72,14 @@ def test_get_top_results_keep_results():
 
 
 def test_run_tflite_module__with_profile__valid_input(
-    tflite_mobilenet_v1_1_quant, tflite_tvmc_compiler, imagenet_cat
+    tflite_mobilenet_v1_1_quant, tflite_compile_model, imagenet_cat
 ):
     # some CI environments wont offer TFLite, so skip in case it is not present
     pytest.importorskip("tflite")
 
     inputs = np.load(imagenet_cat)
 
-    tflite_compiled_model = tflite_tvmc_compiler(tflite_mobilenet_v1_1_quant)
+    tflite_compiled_model = tflite_compile_model(tflite_mobilenet_v1_1_quant)
     result = tvmc.run(
         tflite_compiled_model,
         inputs=inputs,