Fuzz tester for as_completed(), by Glenn Langford. (See issue #127.)

1 files changed, 69 insertions, 0 deletions

diff --git a/examples/fuzz_as_completed.py b/examples/fuzz_as_completed.py
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+#!/usr/bin/env python3
+
+"""Fuzz tester for as_completed(), by Glenn Langford."""
+
+import asyncio
+import itertools
+import random
+import sys
+
+@asyncio.coroutine
+def sleeper(time):
+    yield from asyncio.sleep(time)
+    return time
+
+@asyncio.coroutine
+def watcher(tasks,delay=False):
+    res = []
+    for t in asyncio.as_completed(tasks):
+        r = yield from t
+        res.append(r)
+        if delay:
+            # simulate processing delay
+            process_time = random.random() / 10
+            yield from asyncio.sleep(process_time)
+    #print(res)
+    #assert(sorted(res) == res)
+    if sorted(res) != res:
+        print('FAIL', res)
+        print('------------')
+    else:
+        print('.', end='')
+        sys.stdout.flush()
+
+loop = asyncio.get_event_loop()
+
+print('Pass 1')
+# All permutations of discrete task running times must be returned
+# by as_completed in the correct order.
+task_times = [0, 0.1, 0.2, 0.3, 0.4 ] # 120 permutations
+for times in itertools.permutations(task_times):
+    tasks = [ asyncio.Task(sleeper(t)) for t in times ]
+    loop.run_until_complete(asyncio.Task(watcher(tasks)))
+
+print()
+print('Pass 2')
+# Longer task times, with randomized duplicates. 100 tasks each time.
+longer_task_times = [x/10 for x in range(30)]
+for i in range(20):
+    task_times = longer_task_times * 10
+    random.shuffle(task_times)
+    #print('Times', task_times[:500])
+    tasks = [ asyncio.Task(sleeper(t)) for t in task_times[:100] ]
+    loop.run_until_complete(asyncio.Task(watcher(tasks)))
+
+print()
+print('Pass 3')
+# Same as pass 2, but with a random processing delay (0 - 0.1s) after
+# retrieving each future from as_completed and 200 tasks. This tests whether
+# the order that callbacks are triggered is preserved through to the
+# as_completed caller.
+for i in range(20):
+    task_times = longer_task_times * 10
+    random.shuffle(task_times)
+    #print('Times', task_times[:200])
+    tasks = [ asyncio.Task(sleeper(t)) for t in task_times[:200] ]
+    loop.run_until_complete(asyncio.Task(watcher(tasks, delay=True)))
+
+print()
+loop.close()