#7110: have regrtest print test failures and tracebacks to stderr not stdout.

Patch by Sandro Tosi.

Lib/test/regrtest.py

@@ -957,16 +957,16 @@ def runtest_inner(test, verbose, quiet,
     except KeyboardInterrupt:
         raise
     except support.TestFailed as msg:
-        print("test", test, "failed --", msg)
+        print("test", test, "failed --", msg, file=sys.stderr)
-        sys.stdout.flush()
+        sys.stderr.flush()
         return FAILED, test_time
     except:
         type, value = sys.exc_info()[:2]
-        print("test", test, "crashed --", str(type) + ":", value)
+        print("test", test, "crashed --", str(type) + ":", value, file=sys.stderr)
-        sys.stdout.flush()
+        sys.stderr.flush()
         if verbose or debug:
-            traceback.print_exc(file=sys.stdout)
+            traceback.print_exc(file=sys.stderr)
-            sys.stdout.flush()
+            sys.stderr.flush()
         return FAILED, test_time
     else:
         if refleak:

Misc/ACKS

@@ -818,6 +818,7 @@ Frank J. Tobin
 R Lindsay Todd
 Bennett Todd
 Matias Torchinsky
+Sandro Tosi
 Richard Townsend
 Laurence Tratt
 John Tromp

Misc/NEWS

@@ -260,6 +260,9 @@ Tools/Demos
 Tests
 -----
 
+- Issue #7110: regrtest now sends test failure reports and single-failure
+  tracebacks to stderr rather than stdout.
+
 - Issue #9628: fix runtests.sh -x option so more than one test can be excluded.
 
 - Issue #9899: Fix test_tkinter.test_font on various platforms.  Patch by