feat(engine): add isPlanBlocked plan DAG helper

packages/gittensory-engine/README.md

@@ -536,6 +536,7 @@ dashboard progress summaries:
 - `hasPlanRunningSteps(plan)` — any step is `running`
 - `hasPlanSkippedSteps(plan)` — any step is `skipped`
 - `hasPlanCompletedSteps(plan)` — any step is `completed`
+- `isPlanBlocked(plan)` — pending steps remain but none are runnable (deadlock; mirrors `planProgress`'s `blocked` status)
 
 ## Opportunity competition
 

packages/gittensory-engine/src/index.ts

@@ -146,6 +146,7 @@ export { hasPlanPendingSteps } from "./plan-pending.js";
 export { hasPlanRunningSteps } from "./plan-running.js";
 export { hasPlanSkippedSteps } from "./plan-skipped.js";
 export { hasPlanCompletedSteps } from "./plan-completed.js";
+export { isPlanBlocked } from "./plan-blocked.js";
 export * from "./plan-templates.js";
 export * from "./portfolio/queue.js";
 export {

packages/gittensory-engine/src/plan-blocked.ts

@@ -0,0 +1,26 @@
+import type { PlanDag, PlanStep, PlanStepStatus } from "./plan-export.js";
+
+const isDone = (status: PlanStepStatus): boolean => status === "completed" || status === "skipped";
+
+function nextReadySteps(plan: PlanDag): PlanStep[] {
+  const statusById = new Map(plan.steps.map((step) => [step.id, step.status]));
+  return plan.steps.filter(
+    (step) => step.status === "pending" && step.dependsOn.every((dep) => isDone(statusById.get(dep) ?? "pending")),
+  );
+}
+
+/**
+ * Return whether the plan is deadlocked: pending steps remain but none are runnable. Mirrors the `blocked`
+ * branch of hosted `planProgress` — failed or running plans are not considered blocked. Pure.
+ */
+export function isPlanBlocked(plan: PlanDag): boolean {
+  const total = plan.steps.length;
+  if (total === 0) return false;
+  const completed = plan.steps.filter((step) => step.status === "completed").length;
+  const skipped = plan.steps.filter((step) => step.status === "skipped").length;
+  if (completed + skipped === total) return false;
+  if (plan.steps.some((step) => step.status === "failed")) return false;
+  if (plan.steps.some((step) => step.status === "running")) return false;
+  const pending = plan.steps.some((step) => step.status === "pending");
+  return pending && nextReadySteps(plan).length === 0;
+}

test/unit/plan-blocked.test.ts

@@ -0,0 +1,90 @@
+import { describe, expect, it } from "vitest";
+
+import { isPlanBlocked } from "../../packages/gittensory-engine/src/plan-blocked";
+import type { PlanStep } from "../../packages/gittensory-engine/src/plan-export";
+
+function step(over: Partial<PlanStep> & { id: string; title: string }): PlanStep {
+  return {
+    actionClass: undefined,
+    dependsOn: [],
+    status: "pending",
+    attempts: 0,
+    maxAttempts: 3,
+    lastError: null,
+    ...over,
+  };
+}
+
+describe("isPlanBlocked", () => {
+  it("returns false for an empty plan", () => {
+    expect(isPlanBlocked({ steps: [] })).toBe(false);
+  });
+
+  it("returns false when pending steps are still runnable", () => {
+    expect(
+      isPlanBlocked({
+        steps: [
+          step({ id: "a", title: "Build", status: "pending" }),
+          step({ id: "b", title: "Test", status: "pending", dependsOn: ["a"] }),
+        ],
+      }),
+    ).toBe(false);
+  });
+
+  it("returns true for a cyclic deadlock with no ready steps", () => {
+    expect(
+      isPlanBlocked({
+        steps: [
+          step({ id: "a", title: "A", dependsOn: ["b"] }),
+          step({ id: "b", title: "B", dependsOn: ["a"] }),
+        ],
+      }),
+    ).toBe(true);
+  });
+
+  it("returns false when a step failed (failed takes precedence over blocked)", () => {
+    expect(
+      isPlanBlocked({
+        steps: [
+          step({ id: "a", title: "A", dependsOn: ["b"], status: "failed" }),
+          step({ id: "b", title: "B", dependsOn: ["a"] }),
+        ],
+      }),
+    ).toBe(false);
+  });
+
+  it("returns false when a step is running", () => {
+    expect(
+      isPlanBlocked({
+        steps: [
+          step({ id: "a", title: "A", dependsOn: ["b"], status: "running" }),
+          step({ id: "b", title: "B", dependsOn: ["a"] }),
+        ],
+      }),
+    ).toBe(false);
+  });
+
+  it("returns false when every step is completed or skipped", () => {
+    expect(
+      isPlanBlocked({
+        steps: [
+          step({ id: "a", title: "Build", status: "completed" }),
+          step({ id: "b", title: "Deploy", status: "skipped" }),
+        ],
+      }),
+    ).toBe(false);
+  });
+
+  it("is exported from the package barrel", async () => {
+    const barrel = await import("../../packages/gittensory-engine/src/index");
+    expect(typeof barrel.isPlanBlocked).toBe("function");
+    expect(
+      barrel.isPlanBlocked({
+        steps: [
+          step({ id: "a", title: "A", dependsOn: ["b"] }),
+          step({ id: "b", title: "B", dependsOn: ["a"] }),
+        ],
+      }),
+    ).toBe(true);
+  });
+});