refactor(workflows): extract invokeStep from settle

Author: TheGreatAxios

src/workflows/runtime.ts

@@ -180,58 +180,67 @@ export class WorkflowRuntime {
         continue;
       }
 
-      const resolution = resolveStep(step, this.capabilities);
-      if (!resolution.runnable) {
-        frame.statuses[frame.stepIndex] = "skipped";
-        this.emit({
-          type: "step-skip",
-          workflow: workflow.name,
-          step,
-          reason: resolution.skippedReason ?? "not runnable",
-        });
-        frame.stepIndex += 1;
-        continue;
-      }
-
-      if (step.workflow !== undefined) {
-        const nested = this.resolve(step.workflow);
-        if (nested === undefined) {
-          if (step.optional === true) {
-            frame.statuses[frame.stepIndex] = "skipped";
-            this.emit({
-              type: "step-skip",
-              workflow: workflow.name,
-              step,
-              reason: `sub-workflow not found: ${step.workflow}`,
-            });
-            frame.stepIndex += 1;
-            continue;
-          }
-          throw new Error(
-            `Sub-workflow "${step.workflow}" not found in registry`,
-          );
-        }
-        if (this.stack.length >= MAX_WORKFLOW_DEPTH) {
-          throw new Error(
-            `Workflow nesting exceeded the limit of ${MAX_WORKFLOW_DEPTH} (at "${step.workflow}")`,
-          );
-        }
-        frame.statuses[frame.stepIndex] = "active";
-        this.stack.push(frameFor(nested));
-        continue;
-      }
+      if (this.invokeStep(frame, workflow, step)) return;
+      else continue;
+    }
+  }
 
-      // Landed on an executable step.
-      frame.statuses[frame.stepIndex] = "active";
+  private invokeStep(
+    frame: WorkflowFrame,
+    workflow: Workflow,
+    step: WorkflowStep,
+  ): boolean {
+    const resolution = resolveStep(step, this.capabilities);
+    if (!resolution.runnable) {
+      frame.statuses[frame.stepIndex] = "skipped";
       this.emit({
-        type: "step-start",
+        type: "step-skip",
         workflow: workflow.name,
         step,
-        index: frame.stepIndex,
-        total: workflow.steps.length,
+        reason: resolution.skippedReason ?? "not runnable",
       });
-      return;
+      frame.stepIndex += 1;
+      return false;
     }
+
+    if (step.workflow !== undefined) {
+      const nested = this.resolve(step.workflow);
+      if (nested === undefined) {
+        if (step.optional === true) {
+          frame.statuses[frame.stepIndex] = "skipped";
+          this.emit({
+            type: "step-skip",
+            workflow: workflow.name,
+            step,
+            reason: `sub-workflow not found: ${step.workflow}`,
+          });
+          frame.stepIndex += 1;
+          return false;
+        }
+        throw new Error(
+          `Sub-workflow "${step.workflow}" not found in registry`,
+        );
+      }
+      if (this.stack.length >= MAX_WORKFLOW_DEPTH) {
+        throw new Error(
+          `Workflow nesting exceeded the limit of ${MAX_WORKFLOW_DEPTH} (at "${step.workflow}")`,
+        );
+      }
+      frame.statuses[frame.stepIndex] = "active";
+      this.stack.push(frameFor(nested));
+      return false;
+    }
+
+    // Landed on an executable step.
+    frame.statuses[frame.stepIndex] = "active";
+    this.emit({
+      type: "step-start",
+      workflow: workflow.name,
+      step,
+      index: frame.stepIndex,
+      total: workflow.steps.length,
+    });
+    return true;
   }
 
   state(): WorkflowState {

tests/unit/workflows-runtime.test.ts

@@ -318,3 +318,106 @@ test("coordinator ignores errored tool calls", () => {
   );
   expect(rt.currentStep()?.id).toBe("a");
 });
+
+test("CL-8289 pin: capability skip emits reason and satisfied run lands on gated step", () => {
+  const skipped = new WorkflowRuntime(empty, resolver);
+  const skippedEvents = collect(skipped);
+  skipped.start(withGatedStep);
+  skipped.advance();
+  expect(skipped.currentStep()?.id).toBe("c");
+  const skip = skippedEvents.find(
+    (e) => e.type === "step-skip" && e.step.id === "needs-ticket",
+  );
+  expect(skip?.type).toBe("step-skip");
+  if (skip?.type === "step-skip") {
+    expect(skip.reason).toBe("capability not satisfied: ticket-tracker");
+  }
+
+  const satisfied = new WorkflowRuntime(ticketTracker, resolver);
+  satisfied.start(withGatedStep);
+  satisfied.advance();
+  expect(satisfied.currentStep()?.id).toBe("needs-ticket");
+});
+
+test("CL-8289 pin: sub-workflow descends parent to child then pops complete to p3", () => {
+  const rt = new WorkflowRuntime(empty, resolver);
+  const events = collect(rt);
+  rt.start(parent);
+  expect(rt.currentStep()?.id).toBe("p1");
+  rt.advance();
+  expect(rt.currentStep()?.id).toBe("c1");
+  rt.advance();
+  expect(rt.currentStep()?.id).toBe("p3");
+  expect(events.map((e) => e.type)).toEqual([
+    "step-start",
+    "step-complete",
+    "step-start",
+    "step-complete",
+    "step-complete",
+    "step-start",
+  ]);
+});
+
+test("CL-8289 pin: optional missing sub-workflow skips with not-found prefix", () => {
+  const optionalMissing: Workflow = {
+    name: "optional-missing",
+    description: "optional absent child",
+    steps: [{ id: "o", label: "O", workflow: "nope", optional: true }],
+  };
+  const rt = new WorkflowRuntime(empty, (n) =>
+    n === "optional-missing" ? optionalMissing : undefined,
+  );
+  const events = collect(rt);
+  rt.start(optionalMissing);
+  expect(rt.isComplete()).toBe(true);
+  const skip = events.find((e) => e.type === "step-skip");
+  expect(skip?.type).toBe("step-skip");
+  if (skip?.type === "step-skip") {
+    expect(skip.reason.startsWith("sub-workflow not found: ")).toBe(true);
+    expect(skip.reason).toBe("sub-workflow not found: nope");
+  }
+});
+
+test("CL-8289 pin: required missing sub-workflow throws not-found text", () => {
+  const requiredMissing: Workflow = {
+    name: "required-missing",
+    description: "required absent child",
+    steps: [{ id: "r", label: "R", workflow: "nope" }],
+  };
+  const rt = new WorkflowRuntime(empty, (n) =>
+    n === "required-missing" ? requiredMissing : undefined,
+  );
+  expect(() => rt.start(requiredMissing)).toThrow(
+    'Sub-workflow "nope" not found in registry',
+  );
+});
+
+test("CL-8289 pin: depth limit throws nesting text", () => {
+  const cyclic: Workflow = {
+    name: "cyclic",
+    description: "calls itself",
+    steps: [{ id: "loop", label: "Loop", workflow: "cyclic" }],
+  };
+  const rt = new WorkflowRuntime(empty, (n) =>
+    n === "cyclic" ? cyclic : undefined,
+  );
+  expect(() => rt.start(cyclic)).toThrow(
+    'Workflow nesting exceeded the limit of 3 (at "cyclic")',
+  );
+});
+
+test("CL-8289 pin: two-step golden transcript", () => {
+  const rt = new WorkflowRuntime(empty, resolver);
+  const events = collect(rt);
+  rt.start(simple);
+  rt.advance();
+  rt.advance();
+  expect(rt.isComplete()).toBe(true);
+  expect(events.map((e) => e.type)).toEqual([
+    "step-start",
+    "step-complete",
+    "step-start",
+    "step-complete",
+    "workflow-complete",
+  ]);
+});