feat(plugin-system): plan 07 frontend plugin manager ui

1 files changed, 58 insertions, 0 deletions

diff --git a/src/features/plugins/logic/prereqs.test.ts b/src/features/plugins/logic/prereqs.test.ts
new file mode 100644
index 0000000..704399c
--- /dev/null
+++ b/src/features/plugins/logic/prereqs.test.ts
@@ -0,0 +1,58 @@
+import { describe, expect, it } from "vitest";
+import { autoCheckBackendPrereqs } from "./prereqs";
+import { node } from "./test-fixtures";
+
+describe("autoCheckBackendPrereqs", () => {
+  it("returns [] when all dependencies are already loaded", () => {
+    const nodes = [node({ id: "dep" }), node({ id: "app", dependsOn: ["dep"] })];
+    expect(autoCheckBackendPrereqs("app", nodes)).toEqual([]);
+  });
+
+  it("returns the unloaded direct dependencies (to auto-check)", () => {
+    const nodes = [
+      node({ id: "dep", loaded: false, section: "discovered" }),
+      node({ id: "other", loaded: false, section: "discovered" }),
+      node({ id: "loaded-dep" }),
+      node({ id: "app", dependsOn: ["dep", "other", "loaded-dep"] }),
+    ];
+    // Only the UNLOADED deps are returned (loaded-dep needs no auto-check).
+    expect(autoCheckBackendPrereqs("app", nodes)).toEqual(["dep", "other"]);
+  });
+
+  it("is transitive (dep of a dep)", () => {
+    const nodes = [
+      node({ id: "base", loaded: false, section: "discovered" }),
+      node({ id: "mid", loaded: false, section: "discovered", dependsOn: ["base"] }),
+      node({ id: "app", dependsOn: ["mid"] }),
+    ];
+    // Load order: dependencies BEFORE their dependents.
+    expect(autoCheckBackendPrereqs("app", nodes)).toEqual(["mid", "base"]);
+  });
+
+  it("is one-directional: it never pulls DEPENDENTS in (no reverse traversal)", () => {
+    // Checking `dep` must not auto-check `app` (app depends on dep, not vice versa).
+    const nodes = [
+      node({ id: "dep", loaded: false, section: "discovered" }),
+      node({ id: "app", dependsOn: ["dep"] }),
+    ];
+    expect(autoCheckBackendPrereqs("dep", nodes)).toEqual([]);
+  });
+
+  it("excludes the target itself and skips already-seen nodes (diamond)", () => {
+    const nodes = [
+      node({ id: "base", loaded: false, section: "discovered" }),
+      node({ id: "left", loaded: false, section: "discovered", dependsOn: ["base"] }),
+      node({ id: "right", loaded: false, section: "discovered", dependsOn: ["base"] }),
+      node({ id: "app", dependsOn: ["left", "right"] }),
+    ];
+    expect(autoCheckBackendPrereqs("app", nodes)).toEqual(["left", "right", "base"]);
+  });
+
+  it("returns [] for an unknown target", () => {
+    expect(autoCheckBackendPrereqs("ghost", [node({ id: "a" })])).toEqual([]);
+  });
+
+  it("returns [] for a target with no dependencies", () => {
+    expect(autoCheckBackendPrereqs("app", [node({ id: "app" })])).toEqual([]);
+  });
+});