Concurrent custom branch check

.github/workflows/main.yml

@@ -117,7 +117,7 @@ jobs:
         path: |
           hypothesis-python/.coverage*
           !hypothesis-python/.coveragerc
-          hypothesis-python/branch-check
+          hypothesis-python/branch-check*
 
   test-win:
     runs-on: windows-latest

.gitignore

@@ -11,7 +11,7 @@
 # generic build components
 
 .runtimes
-/hypothesis-python/branch-check
+/hypothesis-python/branch-check*
 /pythonpython3.*
 /pythonpypy3.*
 .pyodide-xbuildenv

hypothesis-python/scripts/validate_branch_check.py

@@ -11,10 +11,12 @@
 import json
 import sys
 from collections import defaultdict
+from pathlib import Path
 
 if __name__ == "__main__":
-    with open("branch-check", encoding="utf-8") as i:
-        data = [json.loads(l) for l in i]
+    data = []
+    for p in Path.cwd().glob("branch-check*"):
+        data.extend(json.loads(l) for l in p.read_text("utf-8").splitlines())
 
     checks = defaultdict(set)
 

hypothesis-python/src/hypothesis/internal/coverage.py

@@ -61,7 +61,7 @@ def record_branch(name, value):
         if key in written:
             return
         written.add(key)
-        with open("branch-check", mode="a", encoding="utf-8") as log:
+        with open(f"branch-check-{os.getpid()}", mode="a", encoding="utf-8") as log:
             log.write(json.dumps({"name": name, "value": value}) + "\n")
 
     description_stack = []

hypothesis-python/tox.ini

@@ -166,7 +166,7 @@ setenv=
     PYTHONWARNDEFAULTENCODING=1
     HYPOTHESIS_INTERNAL_COVERAGE=true
 commands_pre =
-    rm -f branch-check
+    rm -f branch-check*
     pip install .[zoneinfo]
 # Produce a coverage report even if the test suite fails.
 # (The tox task will still count as failed.)