1 files changed, 65 insertions, 0 deletions
diff --git a/testing/web-platform/tests/html/semantics/scripting-1/the-script-element/json-module-assertions/repeated-imports.any.js b/testing/web-platform/tests/html/semantics/scripting-1/the-script-element/json-module-assertions/repeated-imports.any.js
new file mode 100644
index 0000000000..5cc3ee5b7c
--- /dev/null
+++ b/testing/web-platform/tests/html/semantics/scripting-1/the-script-element/json-module-assertions/repeated-imports.any.js
@@ -0,0 +1,65 @@
+// META: global=window,dedicatedworker,sharedworker
+// META: script=/common/utils.js
+
+promise_test(async test => {
+    await promise_rejects_js(test, TypeError,
+      import("./module.json"),
+      "Dynamic import of a JSON module without a type assertion should fail");
+
+    // This time the import should succeed because we're using the correct
+    // import even though the previous attempt with the same  specifier failed.
+    const result = await import("./module.json", { assert: { type: "json" } });
+    assert_true(result.default.test);
+}, "Importing a specifier that previously failed due to an incorrect type assertion can succeed if the correct assertion is later given");
+
+promise_test(async test => {
+    // Append a URL fragment to the specifier so that this is independent
+    // from the previous test.
+    const result = await import("./module.json#2", { assert: { type: "json" } });
+    assert_true(result.default.test);
+
+    await promise_rejects_js(test, TypeError,
+      import("./module.json#2"),
+      "Dynamic import should fail with the type assertion missing even if the same specifier previously succeeded");
+}, "Importing a specifier that previously succeeded with the correct type assertion should fail if the incorrect assertion is later given");
+
+promise_test(async test => {
+    const uuid_token = token();
+    // serve-json-then-js.py gives us JSON the first time
+    const result_json = await import(`../serve-json-then-js.py?key=${uuid_token}`, { assert: { type: "json" } });
+    assert_equals(result_json.default.hello, "world");
+
+    // Import using the same specifier again; this time we get JS, which
+    // should succeed since we're not asserting a non-JS type this time.
+    const result_js = await import(`../serve-json-then-js.py?key=${uuid_token}`);
+    assert_equals(result_js.default, "hello");
+}, "Two modules of different type with the same specifier can load if the server changes its responses");
+
+promise_test(async test => {
+    const uuid_token = token();
+    // serve-json-then-js.py gives us JSON the first time
+    await promise_rejects_js(test, TypeError,
+      import(`../serve-json-then-js.py?key=${uuid_token}`),
+      "Dynamic import of JS with a JSON type assertion should fail");
+
+    // Import using the same specifier/module type pair again; this time we get JS,
+    // but the import should still fail because the module map entry for this
+    // specifier/module type pair already contains a failure.
+    await promise_rejects_js(test, TypeError,
+      import(`../serve-json-then-js.py?key=${uuid_token}`),
+      "import should always fail if the same specifier/type assertion pair failed previously");
+}, "An import should always fail if the same specifier/type assertion pair failed previously");
+
+promise_test(async test => {
+    const uuid_token = token();
+    // serve-json-then-js.py gives us JSON the first time
+    const result_json = await import(`../serve-json-then-js.py?key=${uuid_token}`, { assert: { type: "json" } });
+    assert_equals(result_json.default.hello, "world");
+
+    // If this were to do another fetch, the import would fail because
+    // serve-json-then-js.py would give us JS this time. But, the module map
+    // entry for this specifier/module type pair already exists, so we
+    // successfully reuse the entry instead of fetching again.
+    const result_json_2 = await import(`../serve-json-then-js.py?key=${uuid_token}`, { assert: { type: "json" } });
+    assert_equals(result_json_2.default.hello, "world");
+}, "If an import previously succeeded for a given specifier/type assertion pair, future uses of that pair should yield the same result");