bugfix - ignore go module stdErr messages

ignore if prefix is 'go: downloading' or 'go: extracting'

testjson/execution.go

@@ -317,6 +317,11 @@ func readStderr(in io.Reader, handle errHandler, exec *Execution) chan error {
 		defer close(wait)
 		scanner := bufio.NewScanner(in)
 		for scanner.Scan() {
+			// TODO: remove this check if go module events stop being output as stdErr
+			if checkIsGoModuleEvent(scanner.Text()) {
+				continue
+			}
+
 			exec.addError(scanner.Text())
 			if err := handle(scanner.Text()); err != nil {
 				wait <- err
@@ -328,6 +333,17 @@ func readStderr(in io.Reader, handle errHandler, exec *Execution) chan error {
 	return wait
 }
 
+func checkIsGoModuleEvent(scannerText string) bool {
+	prefixes := [2]string{"go: extracting", "go: downloading"}
+
+	for _, prefix := range prefixes {
+		if strings.HasPrefix(scannerText, prefix) {
+			return true
+		}
+	}
+	return false
+}
+
 func parseEvent(raw []byte) (TestEvent, error) {
 	// TODO: this seems to be a bug in the `go test -json` output
 	if bytes.HasPrefix(raw, []byte("FAIL")) {