More executor tests

somewhat higher coverage for executor classes.

tests/test_concurrent_executor.py

@@ -3,28 +3,40 @@
 """
 
 from datacube.executor import get_executor
+from time import sleep
 import pytest
 
 DATA = [1, 2, 3, 4]
 
 
 def _echo(x, please_fail=False):
-    if please_fail:
+    if please_fail or x == 'please fail':
         raise IOError('Fake I/O error, cause you asked')
     return x
 
 
-def test_concurrent_executor():
-    runner = get_executor(None, 2)
-
+def run_tests_for_runner(runner, sleep_amount=0.5):
+    # get_ready: mostly pending
     futures = runner.map(_echo, DATA)
     assert len(futures) == len(DATA)
-
     completed, failed, pending = runner.get_ready(futures)
-
     assert len(failed) == 0
     assert len(completed) + len(pending) == len(DATA)
 
+    # get_ready: processed + failure
+    data = ['please fail'] + DATA
+    futures = runner.map(_echo, data)
+    assert len(futures) == len(data)
+    sleep(sleep_amount)  # give it "enough" time to finish
+    completed, failed, pending = runner.get_ready(futures)
+    if sleep_amount:
+        assert len(failed) == 1
+    else:
+        assert len(failed) in [0, 1]
+
+    assert len(completed) + len(pending) + len(failed) == len(data)
+
+    # test results
     futures = runner.map(_echo, DATA)
     results = runner.results(futures)
 
@@ -37,3 +49,31 @@ def test_concurrent_executor():
     for ff in runner.as_completed([future]):
         with pytest.raises(IOError):
             runner.result(ff)
+
+    # Next completed with data
+    future = runner.submit(_echo, 'tt')
+    futures = [future]
+    result, futures = runner.next_completed(futures, 'default')
+    assert len(futures) == 0
+    print(type(result), result)
+
+    # Next completed with empty list
+    result, futures = runner.next_completed([], 'default')
+    assert result == 'default'
+    assert len(futures) == 0
+
+    runner.release(future)
+
+
+def test_concurrent_executor():
+    runner = get_executor(None, 2)
+    assert str(runner).find('Multi') >= 0
+
+    run_tests_for_runner(runner, 0.3)
+
+
+def test_fallback_executor():
+    runner = get_executor(None, None)
+    assert str(runner).find('Serial') >= 0
+
+    run_tests_for_runner(runner, 0)