test: enforce exact TechLog contract keys

tests/features/tech-log/studio-contract.test.ts

@@ -9,6 +9,13 @@ import type {
   StudioGateway,
 } from "../../../src/features/tech-log/application/ports/studio-gateway.ts";
 
+type Equal<Left, Right> =
+  (<Value>() => Value extends Left ? 1 : 2) extends
+  (<Value>() => Value extends Right ? 1 : 2)
+    ? true
+    : false;
+type Assert<Condition extends true> = Condition;
+
 type Inline = components["schemas"]["Inline"];
 type CaseRenderBlock = components["schemas"]["CaseRenderBlock"];
 
@@ -40,39 +47,24 @@ const blocks: CaseRenderBlock[] = [
   { type: "EVIDENCE_FIGURE", key: "fetch-plan", alt: "Fetch plan", caption: "Measured fetch plan", zoom: true },
 ];
 
-const gatewayMethodNames = [
-  "getDashboard",
-  "listDocuments",
-  "createDocument",
-  "getDocument",
-  "saveDocument",
-  "validateDocument",
-  "createPreview",
-  "getCurrentPreview",
-  "publishDocument",
-  "unpublishPublication",
-  "listPublications",
-  "getPublicationSnapshot",
-  "getCatalog",
-] as const;
+type RequiredStudioGatewayOperation =
+  | "getDashboard"
+  | "listDocuments"
+  | "createDocument"
+  | "getDocument"
+  | "saveDocument"
+  | "validateDocument"
+  | "createPreview"
+  | "getCurrentPreview"
+  | "publishDocument"
+  | "unpublishPublication"
+  | "listPublications"
+  | "getPublicationSnapshot"
+  | "getCatalog";
 
-function gatewayWithEveryRequiredMethod(): StudioGateway {
-  return {
-    getDashboard: async () => undefined as never,
-    listDocuments: async () => undefined as never,
-    createDocument: async () => undefined as never,
-    getDocument: async () => undefined as never,
-    saveDocument: async () => undefined as never,
-    validateDocument: async () => undefined as never,
-    createPreview: async () => undefined as never,
-    getCurrentPreview: async () => undefined as never,
-    publishDocument: async () => undefined as never,
-    unpublishPublication: async () => undefined as never,
-    listPublications: async () => undefined as never,
-    getPublicationSnapshot: async () => undefined as never,
-    getCatalog: async () => undefined as never,
-  };
-}
+type StudioGatewayExposesNoMissingOrAdditionalOperations = Assert<
+  Equal<keyof StudioGateway, RequiredStudioGatewayOperation>
+>;
 
 describe("TechLog Studio contracts", () => {
   it("preserves every public wire discriminator exactly once", () => {
@@ -98,26 +90,20 @@ describe("TechLog Studio contracts", () => {
     expect(new Set(blocks.map((block) => block.type)).size).toBe(blocks.length);
   });
 
-  it("requires the exact Studio gateway operation set", () => {
-    expect(Object.keys(gatewayWithEveryRequiredMethod()).sort()).toEqual(
-      [...gatewayMethodNames].sort(),
-    );
-  });
-
   it("keeps RFC 9457-style gateway failures inspectable at the application boundary", () => {
     const error = new StudioGatewayError({
       type: "https://techlog.dev/problems/conflict",
       title: "Conflict",
       status: 409,
       detail: "The working copy has changed.",
-      code: "DOCUMENT_VERSION_CONFLICT",
+      code: "VERSION_CONFLICT",
       retryable: false,
     });
 
     expect(error).toMatchObject({
       name: "StudioGatewayError",
       status: 409,
-      code: "DOCUMENT_VERSION_CONFLICT",
+      code: "VERSION_CONFLICT",
       retryable: false,
     });
     expect(isStudioGatewayError(error)).toBe(true);