Adjust typing check to use wrapper/shim script for now.

Author: Sachaa-Thanasius

Diff for: tests/verify_types.py

@@ -0,0 +1,77 @@
+"""This script is a shim around `pyright --verifytypes` to determine if the
+current typing coverage meets the expected coverage. The previous command by
+itself won't suffice, since its expected coverage can't be modified from 100%.
+Useful while still adding annotations to the library.
+"""
+
+import argparse
+import json
+import subprocess
+from decimal import Decimal
+
+PYRIGHT_CMD = ("pyright", "--verifytypes", "rfc3986", "--outputjson")
+
+
+def validate_coverage(inp: str) -> Decimal:
+    """Ensure the given coverage score is between 0 and 100 (inclusive)."""
+
+    coverage = Decimal(inp)
+    if not (0 <= coverage <= 100):
+        raise ValueError
+    return coverage
+
+
+def main() -> int:
+    """Determine if rfc3986's typing coverage meets our expected coverage."""
+
+    parser = argparse.ArgumentParser()
+    parser.add_argument(
+        "--fail-under",
+        default=Decimal("75"),
+        type=validate_coverage,
+        help="The target typing coverage to not fall below (default: 75).",
+    )
+    parser.add_argument(
+        "--quiet",
+        action="store_true",
+        help="Whether to hide the full output from `pyright --verifytypes`.",
+    )
+
+    args = parser.parse_args()
+
+    expected_coverage: Decimal = args.fail_under / 100
+    quiet: bool = args.quiet
+
+    try:
+        output = subprocess.check_output(
+            PYRIGHT_CMD,
+            stderr=subprocess.STDOUT,
+            text=True,
+        )
+    except subprocess.CalledProcessError as exc:
+        output = exc.output
+
+    verifytypes_output = json.loads(output)
+    raw_score = verifytypes_output["typeCompleteness"]["completenessScore"]
+    actual_coverage = Decimal(raw_score)
+
+    if not quiet:
+        # Switch back to normal output instead of json, for readability.
+        subprocess.run(PYRIGHT_CMD[:-1])
+
+    if actual_coverage >= expected_coverage:
+        print(
+            f"OK - Required typing coverage of {expected_coverage:.2%} "
+            f"reached. Total typing coverage: {actual_coverage:.2%}."
+        )
+        return 0
+    else:
+        print(
+            f"FAIL - Required typing coverage of {expected_coverage:.2%} not "
+            f"reached. Total typing coverage: {actual_coverage:.2%}."
+        )
+        return 1
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())

Diff for: tox.ini

@@ -43,7 +43,7 @@ commands = flake8 {posargs} src/rfc3986
 [testenv:typing]
 deps =
     pyright
-commands = pyright {posargs:--verifytypes rfc3986}
+commands = python tests/verify_types.py
 
 [testenv:venv]
 commands = {posargs}