tests: exit with correct error code from TestMain

extpass_test and example_filesystems_test did it wrong,
always returning 0.

internal/readpassword/extpass_test.go

@@ -11,7 +11,7 @@ import (
 func TestMain(m *testing.M) {
 	// Shut up info output
 	tlog.Info.Enabled = false
-	m.Run()
+	os.Exit(m.Run())
 }
 
 func TestExtpass(t *testing.T) {

tests/example_filesystems/example_filesystems_test.go

@@ -15,7 +15,7 @@ const statusTxtContent = "It works!\n"
 
 func TestMain(m *testing.M) {
 	test_helpers.ResetTmpDir(true)
-	m.Run()
+	os.Exit(m.Run())
 }
 
 // checkExampleFS - verify that "dir" contains the expected test files

tests/test_helpers/helpers.go

@@ -109,7 +109,11 @@ func Mount(c string, p string, extraArgs ...string) error {
 
 	cmd := exec.Command(GocryptfsBinary, args...)
 	cmd.Stderr = os.Stderr
-	cmd.Stdout = os.Stdout
+	if testing.Verbose() {
+		// Don't show the "deprecated filesystem" warnings by default. These
+		// are not silenced by "-q".
+		cmd.Stdout = os.Stdout
+	}
 	return cmd.Run()
 }