chore: Use built-in importlib.metadata on Python 3.8

docs/changelog.rst

@@ -6,6 +6,11 @@ Changelog
 `Unreleased`_
 -------------
 
+Changed
+~~~~~~~
+
+- Use built-in ``importlib.metadata`` on Python 3.8. `#376`_
+
 `0.23.5`_ - 2020-01-24
 ----------------------
 
@@ -628,6 +633,7 @@ Fixed
 .. _0.3.0: https://github.com/kiwicom/schemathesis/compare/v0.2.0...v0.3.0
 .. _0.2.0: https://github.com/kiwicom/schemathesis/compare/v0.1.0...v0.2.0
 
+.. _#376: https://github.com/kiwicom/schemathesis/issues/376
 .. _#371: https://github.com/kiwicom/schemathesis/issues/371
 .. _#367: https://github.com/kiwicom/schemathesis/issues/367
 .. _#365: https://github.com/kiwicom/schemathesis/issues/365

mypy.ini

@@ -1,5 +1,5 @@
 [mypy]
-python_version = 3.7
+python_version = 3.8
 show_error_context = true
 verbosity = 0
 ignore_missing_imports = true

pyproject.toml

@@ -34,7 +34,7 @@ pyyaml = "^5.1"
 pytest-subtests = "^0.2.1"
 requests = "^2.22"
 click = "^7.0"
-importlib_metadata = "^1.1"
+importlib_metadata = { version = "^1.1", python = "<3.8" }
 werkzeug = "^0.16.0"
 
 [tool.poetry.dev-dependencies]
@@ -64,7 +64,7 @@ multi_line_output = 3
 default_section = "THIRDPARTY"
 include_trailing_comma = true
 known_first_party = "schemathesis"
-known_third_party = ["_pytest", "aiohttp", "attr", "click", "flask", "hypothesis", "hypothesis_jsonschema", "importlib_metadata", "jsonschema", "pytest", "pytest_subtests", "requests", "schemathesis", "werkzeug", "yaml"]
+known_third_party = ["_pytest", "aiohttp", "attr", "click", "flask", "hypothesis", "hypothesis_jsonschema", "jsonschema", "pytest", "pytest_subtests", "requests", "schemathesis", "werkzeug", "yaml"]
 
 [build-system]
 requires = ["poetry>=0.12"]

src/schemathesis/_compat.py

@@ -1,3 +1,4 @@
+# pylint: disable=unused-import
 from contextlib import contextmanager
 from typing import Generator
 from warnings import catch_warnings, simplefilter
@@ -13,3 +14,9 @@ def handle_warnings() -> Generator[None, None, None]:
             yield
     except ImportError:
         yield
+
+
+try:
+    from importlib import metadata
+except ImportError:
+    import importlib_metadata as metadata  # type: ignore

src/schemathesis/cli/output/default.py

@@ -7,8 +7,8 @@
 import click
 from attr import Attribute
 from hypothesis import settings
-from importlib_metadata import version
 
+from ..._compat import metadata
 from ...constants import __version__
 from ...models import Case, Check, Status, TestResult, TestResultSet
 from ...runner import events
@@ -256,9 +256,9 @@ def handle_initialized(context: events.ExecutionContext, event: events.Initializ
         f"platform {platform.system()} -- "
         f"Python {platform.python_version()}, "
         f"schemathesis-{__version__}, "
-        f"hypothesis-{version('hypothesis')}, "
-        f"hypothesis_jsonschema-{version('hypothesis_jsonschema')}, "
-        f"jsonschema-{version('jsonschema')}"
+        f"hypothesis-{metadata.version('hypothesis')}, "
+        f"hypothesis_jsonschema-{metadata.version('hypothesis_jsonschema')}, "
+        f"jsonschema-{metadata.version('jsonschema')}"
     )
     click.echo(versions)
     click.echo(f"rootdir: {os.getcwd()}")

src/schemathesis/constants.py

@@ -1,10 +1,10 @@
 from enum import Enum
 
-from importlib_metadata import PackageNotFoundError, version
+from ._compat import metadata
 
 try:
-    __version__ = version(__package__)
-except PackageNotFoundError:
+    __version__ = metadata.version(__package__)
+except metadata.PackageNotFoundError:
     # Local run without installation
     __version__ = "dev"
 

test/cli/test_commands.py

@@ -6,20 +6,20 @@
 import yaml
 from _pytest.main import ExitCode
 from hypothesis import HealthCheck, Phase, Verbosity
-from importlib_metadata import version
 from requests import Response
 
 from schemathesis import Case
+from schemathesis._compat import metadata
 from schemathesis.checks import ALL_CHECKS
 from schemathesis.loaders import from_path
 from schemathesis.models import Endpoint
 from schemathesis.runner import DEFAULT_CHECKS
 
 PHASES = "explicit, reuse, generate, target, shrink"
-if version("hypothesis") < "4.5":
+if metadata.version("hypothesis") < "4.5":
     PHASES = "explicit, reuse, generate, shrink"
 HEALTH_CHECKS = "data_too_large|filter_too_much|too_slow|return_value|large_base_example|not_a_test_method"
-if version("hypothesis") < "5.0":
+if metadata.version("hypothesis") < "5.0":
     HEALTH_CHECKS = (
         "data_too_large|filter_too_much|too_slow|return_value|hung_test|large_base_example|not_a_test_method"
     )

test/test_package.py

@@ -1,12 +1,16 @@
 import sys
 
-from importlib_metadata import PackageNotFoundError
+from schemathesis._compat import metadata
 
 
 def test_dev_version(monkeypatch, mocker):
     # When Schemathesis is run in dev environment without installation
     monkeypatch.delitem(sys.modules, "schemathesis.constants")
-    mocker.patch("importlib_metadata.version", side_effect=PackageNotFoundError)
+    if sys.version_info < (3, 8):
+        path = "importlib_metadata.version"
+    else:
+        path = "importlib.metadata.version"
+    mocker.patch(path, side_effect=metadata.PackageNotFoundError)
     from schemathesis.constants import __version__
 
     # Then it's version is "dev"