fix: count instances of runmqdevserver correctly on M1 macs

cmd/runmqserver/process.go

@@ -44,14 +44,24 @@ func verifySingleProcess() error {
 func verifyOnlyOne(programName string) (int, error) {
 // #nosec G104
 out, _, _ := command.Run("ps", "-e", "--format", "cmd")
-//if this goes wrong then assume we are the only one
-numOfProg := strings.Count(out, programName)
+lines := strings.Split(out, "\n")
+numOfProg := countLinesWith(lines, programName)
 if numOfProg != 1 {
 return numOfProg, fmt.Errorf("Expected there to be only 1 instance of %s but found %d", programName, numOfProg)
 }
 return numOfProg, nil
 }
 
+func countLinesWith(lines []string, pattern string) int {
+var occurrences int
+for i := range lines {
+if strings.Contains(lines[i], pattern) {
+occurrences += 1
+}
+}
+return occurrences
+}
+
 // Determines the name of the currently running executable.
 func determineExecutable() (string, error) {
 file, err := os.Executable()

cmd/runmqserver/process_test.go

@@ -0,0 +1,29 @@
+/*
+© Copyright IBM Corporation 2017
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE_2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package main
+
+import "testing"
+
+func TestCountLinesWith(t *testing.T) {
+lines := []string{
+"/usr/bin/qemu-x86_x64 /usr/local/bin/runmqdevserver runmqdevserver",
+"date -u",
+}
+got := countLinesWith(lines, "runmqdevserver")
+if got != 1 {
+t.Fatalf("got %d occurances", got)
+}
+}