Implement human-readable variant of CounterExamples

Tools/CleanTest.icl

@@ -373,7 +373,8 @@ where
 					FailedAssertions fas -> "\n  Failed assumptions:\n    " +++
 						replaceSubString "\n" "\n    "
 							(replaceSubString "\t" "  " $ join "\n" $ map printFA fas)
-					CounterExamples ces  -> "\n  CES"
+					CounterExamples ces  -> "\n  Counter-examples:\n  - " +++
+						join "\n  - " (map (replaceSubString "\n" "\n    " o printCE) ces)
 					FailedChildren fcs   -> "\n  Children tests failed: " +++ join ", " (map fst fcs)
 					Crashed              -> "\n  Crashed"
 				_ -> ""
@@ -383,6 +384,11 @@ where
 					Eq -> diffToConsole $ gDiff{|*|} x y
 					_  -> toString x +++ "\n" +++ toString y
 
+				printCE :: CounterExample -> String
+				printCE ce = join " " (map toString ce.counterExample) +++ case ce.failedAssertions of
+					[]  -> ""
+					fas -> ":\n" +++ join "\n" (map printFA ce.failedAssertions)
+
 	return :: !EndEventType !TestRun !*File !*World -> *(!RunResult, !*World)
 	return eet r io w
 	# (_,w) = fclose io w