gotest: change pattern to Test([^a-z].*)?

warn about files with no tests
be clear about where testing warnings come from

R=r
DELTA=18  (12 added, 3 deleted, 3 changed)
OCL=19988
CL=19993

src/cmd/gotest/gotest

@@ -55,13 +55,22 @@ trap "rm -f _testmain.go _testmain.6" 0 1 2 3 14 15
 	# test array
 	echo
 	echo 'var tests = &[]testing.Test {'
+	for ofile in $ofiles
+	do
 		# test functions are named TestFoo
 		# the grep -v eliminates methods and other special names
 		# that have multiple dots.
-	for i in $(6nm -s $ofiles | grep ' T .*·Test[A-Z]' | grep -v '·.*[.·]' | sed 's/.* //; s/·/./')
+		pattern='Test([^a-z].*)?'
+		tests=$(6nm -s $ofile | egrep ' T .*·'$pattern'$' | grep -v '·.*[.·]' | sed 's/.* //; s/·/./')
+		if [ "x$tests" = x ]; then
+			echo 'gotest: warning: no tests matching '$pattern' in '$ofile 1>&2
+		else
+			for i in $tests
 			do
 				echo '	testing.Test{ "'$i'", &'$i' },'
 			done
+		fi
+	done
 	echo '}'
 	# body
 	echo

src/lib/testing.go

@@ -86,7 +86,7 @@ export func Main(tests *[]Test) {
 	flag.Parse();
 	ok := true;
 	if len(tests) == 0 {
-		println("gotest: warning: no tests to run");
+		println("testing: warning: no tests to run");
 	}
 	for i := 0; i < len(tests); i++ {
 		if chatty {