feat(unstable): Support data: urls (#5157)

cli/tests/data_import_test.js

@@ -0,0 +1,59 @@
+import { assertEquals } from "../../std/testing/asserts.ts";
+
+// export const value = 'Successful import'; export default value;
+import data1 from "data:application/javascript;base64,ZXhwb3J0IGNvbnN0IHZhbHVlID0gJ1N1Y2Nlc3NmdWwgaW1wb3J0JzsgZXhwb3J0IGRlZmF1bHQgdmFsdWU7";
+
+Deno.test("static base64 data url import", () => {
+  assertEquals(data1, "Successful import");
+});
+
+Deno.test("dynamic base64 data url import", async () => {
+  const data2 = await import(
+    // export const leet = 1337
+    "data:application/javascript;base64,ZXhwb3J0IGNvbnN0IGxlZXQgPSAxMzM3"
+  );
+  assertEquals(data2.leet, 1337);
+});
+
+Deno.test("dynamic percent-encoding data url import", async () => {
+  const data3 = await import(
+    // export const value = 42;
+    "data:application/javascript,export%20const%20value%20%3D%2042%3B"
+  );
+  assertEquals(data3.value, 42);
+});
+
+Deno.test("dynamic base64 typescript data url import", async () => {
+  const data2 = await import(
+    // export const leet: number = 1337;
+    "data:application/typescript;base64,ZXhwb3J0IGNvbnN0IGxlZXQ6IG51bWJlciA9IDEzMzc7"
+  );
+  assertEquals(data2.leet, 1337);
+});
+
+Deno.test("spawn worker with data url", async () => {
+  let resolve, timeout;
+  const promise = new Promise((res, rej) => {
+    resolve = res;
+    timeout = setTimeout(() => rej("Worker timed out"), 2000);
+  });
+
+  const worker = new Worker(
+    "data:application/javascript," +
+      encodeURIComponent("self.onmessage = () => self.postMessage('Worker');"),
+    { type: "module" },
+  );
+
+  worker.onmessage = (m) => {
+    if (m.data === "Worker") {
+      resolve();
+    }
+  };
+
+  worker.postMessage();
+
+  await promise;
+
+  clearTimeout(timeout);
+  worker.terminate();
+});