Forgot a file..

examples/chip-tool/templates/partials/test_cluster.zapt

@@ -2,7 +2,7 @@
 class {{asCamelCased filename false}}: public TestCommand
 {
   public:
-    {{asCamelCased filename false}}(): TestCommand("{{filename}}") {}
+    {{asCamelCased filename false}}(): TestCommand("{{filename}}"), mTestIndex(0) {}
 
     /////////// TestCommand Interface /////////
     CHIP_ERROR NextTest() override
@@ -15,15 +15,18 @@ class {{asCamelCased filename false}}: public TestCommand
           SetCommandExitStatus(true);
       }
 
-      switch (mTestIndex)
+      // Ensure we increment mTestIndex before we start running the relevant
+      // command.  That way if we lose the timeslice after we send the message
+      // but before our function call returns, we won't end up with an
+      // incorrect mTestIndex value observed when we get the response.
+      switch (mTestIndex++)
       {
         {{#chip_tests_items}}
         case {{index}}:
           err = TestSendCluster{{asCamelCased cluster false}}Command{{asCamelCased command false}}_{{index}}();
           break;
         {{/chip_tests_items}}
       }
-      mTestIndex++;
 
       if (CHIP_NO_ERROR != err)
       {
@@ -36,8 +39,8 @@ class {{asCamelCased filename false}}: public TestCommand
 
 
   private:
-    uint16_t mTestIndex = 0;
-    uint16_t mTestCount = {{totalTests}};
+    std::atomic_uint16_t mTestIndex;
+    const uint16_t mTestCount = {{totalTests}};
 
     //
     // Tests methods