1 files changed, 105 insertions, 0 deletions
diff --git a/packages/web-util/src/tests/swr.ts b/packages/web-util/src/tests/swr.ts
new file mode 100644
index 000000000..d5f4341f3
--- /dev/null
+++ b/packages/web-util/src/tests/swr.ts
@@ -0,0 +1,105 @@
+/*
+ This file is part of GNU Taler
+ (C) 2021 Taler Systems S.A.
+
+ GNU Taler is free software; you can redistribute it and/or modify it under the
+ terms of the GNU General Public License as published by the Free Software
+ Foundation; either version 3, or (at your option) any later version.
+
+ GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
+ WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along with
+ GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+import { ComponentChildren, FunctionalComponent, h, VNode } from "preact";
+import { MockEnvironment } from "./mock.js";
+import { SWRConfig } from "swr";
+import * as swr__internal from "swr/_internal";
+import { Logger } from "@gnu-taler/taler-util";
+import { buildRequestFailed, RequestError } from "../index.browser.js";
+
+const logger = new Logger("tests/swr.ts");
+
+/**
+ * Helper for hook that use SWR inside.
+ *
+ * buildTestingContext() will return a testing context
+ *
+ * @deprecated do not use it, it will be removed
+ */
+export class SwrMockEnvironment extends MockEnvironment {
+  constructor(debug = false) {
+    super(debug);
+  }
+
+  public buildTestingContext(): FunctionalComponent<{
+    children: ComponentChildren;
+  }> {
+    const __SAVE_REQUEST_AND_GET_MOCKED_RESPONSE =
+      this.saveRequestAndGetMockedResponse.bind(this);
+
+    function testingFetcher(params: any): any {
+      const url = JSON.stringify(params);
+      const mocked = __SAVE_REQUEST_AND_GET_MOCKED_RESPONSE<any, any>(
+        {
+          method: "get",
+          url,
+        },
+        {},
+      );
+
+      //unexpected query
+      if (!mocked.expectedQuery) return undefined;
+      const status = mocked.expectedQuery.query.code ?? 200;
+      const requestPayload = mocked.expectedQuery.params?.request;
+      const responsePayload = mocked.expectedQuery.params?.response;
+      //simulated error
+      if (status >= 400) {
+        const error = buildRequestFailed(
+          url,
+          JSON.stringify(responsePayload),
+          status,
+          requestPayload,
+        );
+        //example error handling from https://swr.vercel.app/docs/error-handling
+        throw new RequestError(error);
+      }
+      return responsePayload;
+    }
+
+    const value: Partial<swr__internal.PublicConfiguration> & {
+      provider: () => Map<any, any>;
+    } = {
+      use: [
+        (useSWRNext) => {
+          return (key, fetcher, config) => {
+            //prevent the request
+            //use the testing fetcher instead
+            return useSWRNext(key, testingFetcher, config);
+          };
+        },
+      ],
+      fetcher: testingFetcher,
+      //These options are set for ending the test faster
+      //otherwise SWR will create timeouts that will live after the test finished
+      loadingTimeout: 0,
+      dedupingInterval: 0,
+      shouldRetryOnError: false,
+      errorRetryInterval: 0,
+      errorRetryCount: 0,
+      //clean cache for every test
+      provider: () => new Map(),
+    };
+
+    return function TestingContext({
+      children,
+    }: {
+      children: ComponentChildren;
+    }): VNode {
+      return h(SWRConfig, { value }, children);
+    };
+  }
+}