Detect entry-point of tests automatically

README.md

@@ -312,7 +312,7 @@ $ pip install -e .
 
 This project enforces [black](https://github.com/psf/black) python code formatting.
 
-Before commiting changes run:
+Before committing changes run:
 
 ```bash
 pipenv run black .
@@ -333,7 +333,7 @@ Adding a standard test case is easy.
 
 - Create a new directory `betterproto/tests/inputs/<name>`
   - add `<name>.proto`  with a message called `Test`
-  - add `<name>.json` with some test data
+  - add `<name>.json` with some test data (optional)
 
 It will be picked up automatically when you run the tests.
 

betterproto/tests/README.md

@@ -12,12 +12,12 @@ inputs/
 
 ## Test case directory structure
 
-Each testcase has a `<name>.proto` file with a message called `Test`, a matching `.json` file and optionally a custom test file called `test_*.py`.
+Each testcase has a `<name>.proto` file with a message called `Test`, and optionally a matching `.json` file and a custom test called `test_*.py`.
 
 ```bash
 bool/
   bool.proto
-  bool.json
+  bool.json     # optional
   test_bool.py  # optional
 ```
 
@@ -61,21 +61,22 @@ def test_value():
 
 The following tests are automatically executed for all cases:
 
-- [x] Can the generated python code imported?
+- [x] Can the generated python code be imported?
 - [x] Can the generated message class be instantiated?
 - [x] Is the generated code compatible with the Google's `grpc_tools.protoc` implementation?
+  - _when `.json` is present_ 
 
 ## Running the tests
 
 - `pipenv run generate`  
-  This generates
+  This generates:
   - `betterproto/tests/output_betterproto` &mdash; *the plugin generated python classes*
   - `betterproto/tests/output_reference` &mdash; *reference implementation classes*
 - `pipenv run test`
 
 ## Intentionally Failing tests
 
-The standard test suite includes tests that fail by intention. These tests document known bugs and missing features that are intended to be corrented in the future.
+The standard test suite includes tests that fail by intention. These tests document known bugs and missing features that are intended to be corrected in the future.
 
 When running `pytest`, they show up as `x` or  `X` in the test results.
 

betterproto/tests/inputs/config.py

@@ -1,6 +1,6 @@
 # Test cases that are expected to fail, e.g. unimplemented features or bug-fixes.
 # Remove from list when fixed.
-tests = {
+xfail = {
     "import_circular_dependency",
     "oneof_enum",  # 63
     "casing_message_field_uppercase",  # 11
@@ -10,19 +10,6 @@ tests = {
     "googletypes_value",  # 9
 }
 
-
-# Defines where the main package for this test resides.
-# Needed to test relative package imports.
-packages = {
-    "import_root_package_from_child": ".child",
-    "import_parent_package_from_child": ".parent.child",
-    "import_root_package_from_nested_child": ".nested.child",
-    "import_cousin_package": ".test.subpackage",
-    "import_cousin_package_same_name": ".test.subpackage",
-    "repeatedmessage": ".repeatedmessage",
-    "service": ".service",
-}
-
 services = {
     "googletypes_response",
     "googletypes_response_embedded",

betterproto/tests/test_inputs.py

@@ -3,6 +3,7 @@ import json
 import os
 import sys
 from collections import namedtuple
+from types import ModuleType
 from typing import Set
 
 import pytest
@@ -10,7 +11,12 @@ import pytest
 import betterproto
 from betterproto.tests.inputs import config as test_input_config
 from betterproto.tests.mocks import MockChannel
-from betterproto.tests.util import get_directories, get_test_case_json_data, inputs_path
+from betterproto.tests.util import (
+    find_module,
+    get_directories,
+    get_test_case_json_data,
+    inputs_path,
+)
 
 # Force pure-python implementation instead of C++, otherwise imports
 # break things because we can't properly reset the symbol database.
@@ -50,16 +56,17 @@ class TestCases:
 test_cases = TestCases(
     path=inputs_path,
     services=test_input_config.services,
-    xfail=test_input_config.tests,
+    xfail=test_input_config.xfail,
 )
 
 plugin_output_package = "betterproto.tests.output_betterproto"
 reference_output_package = "betterproto.tests.output_reference"
 
+TestData = namedtuple("TestData", ["plugin_module", "reference_module", "json_data"])
 
-TestData = namedtuple(
-    "TestData", ["plugin_module", "reference_module", "json_data", "entry_point"]
-)
+
+def module_has_entry_point(module: ModuleType):
+    return any(hasattr(module, attr) for attr in ["Test", "TestStub"])
 
 
 @pytest.fixture
@@ -77,18 +84,23 @@ def test_data(request):
 
     sys.path.append(reference_module_root)
 
-    test_package = test_case_name + test_input_config.packages.get(test_case_name, "")
+    plugin_module = importlib.import_module(f"{plugin_output_package}.{test_case_name}")
+
+    plugin_module_entry_point = find_module(plugin_module, module_has_entry_point)
+
+    if not plugin_module_entry_point:
+        raise Exception(
+            f"Test case {repr(test_case_name)} has no entry point. "
+            + "Please add a proto message or service called Test and recompile."
+        )
 
     yield (
         TestData(
-            plugin_module=importlib.import_module(
-                f"{plugin_output_package}.{test_package}"
-            ),
+            plugin_module=plugin_module_entry_point,
             reference_module=lambda: importlib.import_module(
                 f"{reference_output_package}.{test_case_name}.{test_case_name}_pb2"
             ),
             json_data=get_test_case_json_data(test_case_name),
-            entry_point=test_package,
         )
     )
 
@@ -111,7 +123,7 @@ def test_message_equality(test_data: TestData) -> None:
 
 @pytest.mark.parametrize("test_data", test_cases.messages_with_json, indirect=True)
 def test_message_json(repeat, test_data: TestData) -> None:
-    plugin_module, _, json_data, entry_point = test_data
+    plugin_module, _, json_data = test_data
 
     for _ in range(repeat):
         message: betterproto.Message = plugin_module.Test()
@@ -124,13 +136,13 @@ def test_message_json(repeat, test_data: TestData) -> None:
 
 @pytest.mark.parametrize("test_data", test_cases.services, indirect=True)
 def test_service_can_be_instantiated(test_data: TestData) -> None:
-    plugin_module, _, json_data, entry_point = test_data
+    plugin_module, _, json_data = test_data
     plugin_module.TestStub(MockChannel())
 
 
 @pytest.mark.parametrize("test_data", test_cases.messages_with_json, indirect=True)
 def test_binary_compatibility(repeat, test_data: TestData) -> None:
-    plugin_module, reference_module, json_data, entry_point = test_data
+    plugin_module, reference_module, json_data = test_data
 
     reference_instance = Parse(json_data, reference_module().Test())
     reference_binary_output = reference_instance.SerializeToString()

betterproto/tests/util.py

@@ -1,6 +1,9 @@
+import importlib
 import os
+import pathlib
 import subprocess
-from typing import Generator
+from types import ModuleType
+from typing import Callable, Generator, Optional
 
 os.environ["PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION"] = "python"
 
@@ -60,3 +63,25 @@ def get_test_case_json_data(test_case_name, json_file_name=None):
 
     with open(test_data_file_path) as fh:
         return fh.read()
+
+
+def find_module(
+    module: ModuleType, predicate: Callable[[ModuleType], bool]
+) -> Optional[ModuleType]:
+    if predicate(module):
+        return module
+
+    module_path = pathlib.Path(*module.__path__)
+
+    for sub in list(module_path.glob("**/")):
+        if not sub.is_dir() or sub == module_path:
+            continue
+        sub_module_path = sub.relative_to(module_path)
+        sub_module_name = ".".join(sub_module_path.parts)
+
+        sub_module = importlib.import_module(f".{sub_module_name}", module.__name__)
+
+        if predicate(sub_module):
+            return sub_module
+
+    return None