Handle edge case where user reuses step with stepNumber after it was …

…already allocated in loop

inngest-spring-boot-demo/src/main/java/com/inngest/springbootdemo/testfunctions/LoopFunction.java

@@ -22,14 +22,23 @@ public InngestFunctionConfigBuilder config(InngestFunctionConfigBuilder builder)
     public Integer execute(FunctionContext ctx, Step step) {
         int runningCount = 10;
 
+        // explicitly naming a step that the SDK will try to use in the loop shouldn't break the loop
         int effectivelyFinalVariableForLambda1 = runningCount;
         runningCount = step.run("add-num:3", () -> effectivelyFinalVariableForLambda1 + 50, Integer.class);
 
         for (int i = 0; i < 5; i++) {
             int effectivelyFinalVariableForLambda2 = runningCount;
+            // The actual stepIds used will be add-num, add-num:1, add-num:2, add-num:4, add-num:5
             runningCount = step.run("add-num", () -> effectivelyFinalVariableForLambda2 + 10, Integer.class);
         }
 
+        // explicitly reusing step names that the SDK used during the loop should both execute
+        // These will be modified to add-num:4:1 and add-num:4:2 respectively
+        int effectivelyFinalVariableForLambda3 = runningCount;
+        runningCount = step.run("add-num:4", () -> effectivelyFinalVariableForLambda3 + 30, Integer.class);
+        int effectivelyFinalVariableForLambda4 = runningCount;
+        runningCount = step.run("add-num:4", () -> effectivelyFinalVariableForLambda4 + 30, Integer.class);
+
         return runningCount;
     }
 }

inngest-spring-boot-demo/src/test/java/com/inngest/springbootdemo/LoopFunctionIntegrationTest.java

@@ -25,6 +25,6 @@ void testStepsInLoopExecuteCorrectly() throws Exception {
         RunEntry<Object> loopRun = devServer.runsByEvent(loopEvent).first();
         assertEquals("Completed", loopRun.getStatus());
 
-        assertEquals(110, loopRun.getOutput());
+        assertEquals(170, loopRun.getOutput());
     }
 }

inngest/src/main/kotlin/com/inngest/State.kt

@@ -27,21 +27,20 @@ class State(
     }
 
     private fun findNextAvailableStepId(id: String): String {
-        if (id !in stepIdsToNextStepNumber) {
-            stepIdsToNextStepNumber[id] = 1
+        if (id !in stepIds) {
             return id
         }
 
         // start with the seen count so far for current stepId
         // but loop over all seen stepIds to make sure a user didn't explicitly define
         // a step using the same step number
-        var stepNumber = stepIdsToNextStepNumber[id]
+        var stepNumber = stepIdsToNextStepNumber.getOrDefault(id, 1)
         while ("$id:$stepNumber" in stepIds) {
-            stepNumber = stepNumber!! + 1
+            stepNumber = stepNumber + 1
         }
         // now we know stepNumber is unused and can be used for the current stepId
         // save stepNumber + 1 to the hash for next time
-        stepIdsToNextStepNumber[id] = stepNumber!! + 1
+        stepIdsToNextStepNumber[id] = stepNumber + 1
 
         return "$id:$stepNumber"
     }