wait_for helper [wait_for]

hjwp · hjwp · commit 780a9d004a1c · 2019-07-26T15:30:09.000+01:00
diff --git a/tests/e2e/wait_for.py b/tests/e2e/wait_for.py
@@ -0,0 +1,20 @@
+#pylint: disable=bare-except
+import time
+import pytest
+
+def wait_for(fn):
+    """
+    Keep retrying a function, catching any exceptions, until it returns something truthy,
+    or we hit a timeout.
+    """
+    timeout = time.time() + 3
+    while time.time() < timeout:
+        try:
+            r = fn()
+            if r:
+                return r
+        except:
+            if time.time() > timeout:
+                raise
+        time.sleep(0.1)
+    pytest.fail(f'function {fn} never returned anything truthy')
