Run pyright on matrix of platforms and python versions (#5072)

* Run pyright on matrix of platforms and python versions

* Drop 3.10 from matrix, as it fails

tests/pyright_test.py

@@ -1,30 +1,37 @@
 #!/usr/bin/env python3
 
+import shutil
 import subprocess
 import sys
 from pathlib import Path
 
-
+_PYRIGHT_VERSION = "1.1.115"
 _WELL_KNOWN_FILE = Path("tests", "pyright_test.py")
-_PYRIGHT_COMMAND = ["npx", "-p", "pyright@1.1.114", "pyright"]
 
 
 def main() -> None:
-    assert_npm_is_installed()
-    ret = subprocess.run(_PYRIGHT_COMMAND).returncode
-    sys.exit(ret)
-
-
-def assert_npm_is_installed() -> None:
     if not _WELL_KNOWN_FILE.exists():
         print("pyright_test.py must be run from the typeshed root directory", file=sys.stderr)
         sys.exit(1)
+
+    # subprocess.run on Windows does not look in PATH.
+    npx = shutil.which("npx")
+
+    if npx is None:
+        print("error finding npx; is Node.js installed?", file=sys.stderr)
+        sys.exit(1)
+
     try:
-        subprocess.run(["npx", "--version"])
+        subprocess.run([npx, "--version"])
     except OSError:
         print("error running npx; is Node.js installed?", file=sys.stderr)
         sys.exit(1)
 
+    command = [npx, "-p", "pyright@" + _PYRIGHT_VERSION, "pyright"] + sys.argv[1:]
+
+    ret = subprocess.run(command).returncode
+    sys.exit(ret)
+
 
 if __name__ == "__main__":
     main()