Fix flaky tests, by preheating Pyright

Author: laike9m

.github/workflows/test.yaml

@@ -2,7 +2,7 @@ name: Unit Test
 
 on:
   push:
-    branches: [ main ]
+    branches: [ main, test ]
   pull_request:
 
 jobs:
@@ -17,12 +17,14 @@ jobs:
           cache: true
       - name: Install dependencies
         run: pdm install
-      - name: Run tests with retry
-        uses: nick-fields/retry@v2
-        with:
-          timeout_minutes: 10
-          max_attempts: 3
-          command: pdm run test
+      - name: Preheat Pyright
+        # If we don't do this, each pytest-xdist process will try to install the
+        # dependencies of Pyright (Node.js packages, pyi). Each installation assumes
+        # it's a clean install, and will error if files already exist.
+        run: pdm run pyright --pythonversion 3.12 challenges/basic-any/solution.py
+        continue-on-error: true
+      - name: Run tests
+        run: pdm run test
       - name: Send failure email
         if: failure()
         uses: dawidd6/action-send-mail@v3

views/challenge.py

@@ -151,13 +151,16 @@ def _type_check_with_pyright(
                 ["pyright", "--pythonversion", "3.12", temp.name],
                 capture_output=True,
                 text=True,
-            ).stdout
+            )
+            stdout, stderr = raw_result.stdout, raw_result.stderr
+            if stderr:
+                return TypeCheckResult(message=stderr, passed=False)
         error_lines: list[str] = []
 
         # Substract lineno in merged code by lineno_delta, so that the lineno in
         # error message matches those in the test code editor. Fixed #20.
         lineno_delta = len(user_code.splitlines())
-        for line in raw_result.splitlines():
+        for line in stdout.splitlines():
             m = re.match(cls.PYRIGHT_MESSAGE_REGEX, line)
             if m is None:
                 continue