fix: Make IDP routes independent of handlers

test/unit/identity/interaction/routing/InteractionRouteHandler.test.ts

@@ -0,0 +1,53 @@
+import type { Operation } from '../../../../../src/http/Operation';
+import { BasicRepresentation } from '../../../../../src/http/representation/BasicRepresentation';
+import type { Representation } from '../../../../../src/http/representation/Representation';
+import type { InteractionHandler } from '../../../../../src/identity/interaction/InteractionHandler';
+import type { InteractionRoute } from '../../../../../src/identity/interaction/routing/InteractionRoute';
+import { InteractionRouteHandler } from '../../../../../src/identity/interaction/routing/InteractionRouteHandler';
+import { APPLICATION_JSON } from '../../../../../src/util/ContentTypes';
+import { NotFoundHttpError } from '../../../../../src/util/errors/NotFoundHttpError';
+import { createPostJsonOperation } from '../email-password/handler/Util';
+
+describe('An InteractionRouteHandler', (): void => {
+  const path = 'http://example.com/idp/path/';
+  let operation: Operation;
+  let representation: Representation;
+  let route: InteractionRoute;
+  let source: jest.Mocked<InteractionHandler>;
+  let handler: InteractionRouteHandler;
+
+  beforeEach(async(): Promise<void> => {
+    operation = createPostJsonOperation({}, path);
+
+    representation = new BasicRepresentation(JSON.stringify({}), APPLICATION_JSON);
+
+    route = {
+      getPath: jest.fn().mockReturnValue(path),
+    };
+
+    source = {
+      canHandle: jest.fn(),
+      handle: jest.fn().mockResolvedValue(representation),
+    } as any;
+
+    handler = new InteractionRouteHandler(route, source);
+  });
+
+  it('rejects other paths.', async(): Promise<void> => {
+    operation = createPostJsonOperation({}, 'http://example.com/idp/otherPath/');
+    await expect(handler.canHandle({ operation })).rejects.toThrow(NotFoundHttpError);
+  });
+
+  it('rejects input its source cannot handle.', async(): Promise<void> => {
+    source.canHandle.mockRejectedValueOnce(new Error('bad data'));
+    await expect(handler.canHandle({ operation })).rejects.toThrow('bad data');
+  });
+
+  it('can handle requests its source can handle.', async(): Promise<void> => {
+    await expect(handler.canHandle({ operation })).resolves.toBeUndefined();
+  });
+
+  it('lets its source handle requests.', async(): Promise<void> => {
+    await expect(handler.handle({ operation })).resolves.toBe(representation);
+  });
+});