tests: Warn not fail when reading invalid pickle status files

With this change, the test script will output a warning when it reads
an incomplete (e.g., when a regression is still running) or corrupt
status file instead of throwing an exception. When the scipt is used
to show the results the corrupt file is skipped; when it is used to
test if all regressions run successfully it will return an error value
(2).

Change-Id: Ie7d9b457b200e3abc7ae6238e3efbf3d18cf4297
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2320
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

tests/tests.py

@@ -242,8 +242,18 @@ def _show_args(subparsers):
                         help="Pickled test results")
 
 def _show(args):
+    def _load(f):
+        # Load the pickled status file, sometimes e.g., when a
+        # regression is still running the status file might be
+        # incomplete.
+        try:
+            return pickle.load(f)
+        except EOFError:
+            print >> sys.stderr, 'Could not read file %s' % f.name
+            return []
+
     formatter = _create_formatter(args)
-    suites = sum([ pickle.load(f) for f in args.result ], [])
+    suites = sum([ _load(f) for f in args.result ], [])
     formatter.dump_suites(suites)
 
 def _test_args(subparsers):
@@ -276,7 +286,11 @@ def _test_args(subparsers):
                         help="Pickled test results")
 
 def _test(args):
-    suites = sum([ pickle.load(f) for f in args.result ], [])
+    try:
+        suites = sum([ pickle.load(f) for f in args.result ], [])
+    except EOFError:
+        print >> sys.stderr, 'Could not read all files'
+        sys.exit(2)
 
     if all(s for s in suites):
         sys.exit(0)