From b990cba074e7429e01ff4522e01b2b582df4bbf5 Mon Sep 17 00:00:00 2001
From: Guy Bedford <gbedford@cloudflare.com>
Date: Mon, 23 Mar 2026 12:00:54 -0700
Subject: [PATCH] [wasm] Add ESM integration tests for wasm:js/string-constants
 builtin

Tests string constants support in both the instance phase and source
phase Wasm ESM integration, covering the wasm:js/string-constants
import namespace as specified in the JS API spec.

Spec PR: https://github.com/WebAssembly/esm-integration/pull/115
---
 .../resources/js-string-constants.wasm        | Bin 0 -> 217 bytes
 .../resources/js-string-constants.wat         |  11 ++++++
 ...rce-phase-string-builtins.tentative.any.js |   1 +
 ...ce-phase-string-constants.tentative.any.js |  32 ++++++++++++++++++
 .../string-builtins.tentative.any.js          |   1 +
 .../string-constants.tentative.any.js         |  10 ++++++
 6 files changed, 55 insertions(+)
 create mode 100644 wasm/jsapi/esm-integration/resources/js-string-constants.wasm
 create mode 100644 wasm/jsapi/esm-integration/resources/js-string-constants.wat
 create mode 100644 wasm/jsapi/esm-integration/source-phase-string-constants.tentative.any.js
 create mode 100644 wasm/jsapi/esm-integration/string-constants.tentative.any.js

diff --git a/wasm/jsapi/esm-integration/resources/js-string-constants.wasm b/wasm/jsapi/esm-integration/resources/js-string-constants.wasm
new file mode 100644
index 0000000000000000000000000000000000000000..4ba2d9e7c5811f99d888292c55e361cc5c5c79c2
GIT binary patch
literal 217
zcmZQbEY4+QU|?XXXOSoevaPa;^@~f2GV{`Plk@Y6OA_-+iW!*m8E{H6;+191NX^N~
z$ETm=!~7WyKn3h7EUc-y1tpct3><l-IXO<1C8^AeQ2k6msr;-=W@ZKrmb}E=RCYxc
U28e1#PLSgGB%o?0sA7m(0204NYXATM

literal 0
HcmV?d00001

diff --git a/wasm/jsapi/esm-integration/resources/js-string-constants.wat b/wasm/jsapi/esm-integration/resources/js-string-constants.wat
new file mode 100644
index 00000000000000..2de58bc19cdf12
--- /dev/null
+++ b/wasm/jsapi/esm-integration/resources/js-string-constants.wat
@@ -0,0 +1,11 @@
+(module
+  (import "wasm:js/string-constants" "" (global $empty externref))
+  (import "wasm:js/string-constants" "\00" (global $null_byte externref))
+  (import "wasm:js/string-constants" "hello" (global $hello externref))
+  (import "wasm:js/string-constants" "\f0\9f\98\80" (global $emoji externref))
+
+  (export "empty" (global $empty))
+  (export "nullByte" (global $null_byte))
+  (export "hello" (global $hello))
+  (export "emoji" (global $emoji))
+)
diff --git a/wasm/jsapi/esm-integration/source-phase-string-builtins.tentative.any.js b/wasm/jsapi/esm-integration/source-phase-string-builtins.tentative.any.js
index e79b457dd464fc..bedb4d5b6a58bd 100644
--- a/wasm/jsapi/esm-integration/source-phase-string-builtins.tentative.any.js
+++ b/wasm/jsapi/esm-integration/source-phase-string-builtins.tentative.any.js
@@ -37,3 +37,4 @@ promise_test(async () => {
 
   assert_equals(imports.length, 0);
 }, "Source phase import should handle string builtin import reflection correctly");
+
diff --git a/wasm/jsapi/esm-integration/source-phase-string-constants.tentative.any.js b/wasm/jsapi/esm-integration/source-phase-string-constants.tentative.any.js
new file mode 100644
index 00000000000000..66ee89c5394281
--- /dev/null
+++ b/wasm/jsapi/esm-integration/source-phase-string-constants.tentative.any.js
@@ -0,0 +1,32 @@
+// META: global=window,dedicatedworker,jsshell,shadowrealm
+
+promise_test(async () => {
+  const wasmModuleSource = await import.source("./resources/js-string-constants.wasm");
+
+  const instance = new WebAssembly.Instance(wasmModuleSource, {});
+
+  assert_equals(instance.exports.empty.value, "");
+  assert_equals(instance.exports.nullByte.value, "\0");
+  assert_equals(instance.exports.hello.value, "hello");
+  assert_equals(instance.exports.emoji.value, "\u{1F600}");
+}, "String constants from wasm:js/string-constants should be supported in source phase imports");
+
+promise_test(async () => {
+  const wasmModuleSource = await import.source("./resources/js-string-constants.wasm");
+
+  const exports = WebAssembly.Module.exports(wasmModuleSource);
+  const exportNames = exports.map((exp) => exp.name);
+
+  assert_true(exportNames.includes("empty"));
+  assert_true(exportNames.includes("nullByte"));
+  assert_true(exportNames.includes("hello"));
+  assert_true(exportNames.includes("emoji"));
+}, "Source phase import should properly expose string constants exports");
+
+promise_test(async () => {
+  const wasmModuleSource = await import.source("./resources/js-string-constants.wasm");
+
+  const imports = WebAssembly.Module.imports(wasmModuleSource);
+
+  assert_equals(imports.length, 0);
+}, "Source phase import should handle string constants import reflection correctly");
diff --git a/wasm/jsapi/esm-integration/string-builtins.tentative.any.js b/wasm/jsapi/esm-integration/string-builtins.tentative.any.js
index bac8fd92727437..f291c4ff53c453 100644
--- a/wasm/jsapi/esm-integration/string-builtins.tentative.any.js
+++ b/wasm/jsapi/esm-integration/string-builtins.tentative.any.js
@@ -10,3 +10,4 @@ promise_test(async () => {
   assert_equals(wasmModule.testString("hello"), 1);
   assert_equals(wasmModule.testString(42), 0);
 }, "String builtins should be supported in imports in ESM integration");
+
diff --git a/wasm/jsapi/esm-integration/string-constants.tentative.any.js b/wasm/jsapi/esm-integration/string-constants.tentative.any.js
new file mode 100644
index 00000000000000..8166bb4f721726
--- /dev/null
+++ b/wasm/jsapi/esm-integration/string-constants.tentative.any.js
@@ -0,0 +1,10 @@
+// META: global=window,dedicatedworker,jsshell,shadowrealm
+
+promise_test(async () => {
+  const wasmModule = await import("./resources/js-string-constants.wasm");
+
+  assert_equals(wasmModule.empty, "");
+  assert_equals(wasmModule.nullByte, "\0");
+  assert_equals(wasmModule.hello, "hello");
+  assert_equals(wasmModule.emoji, "\u{1F600}");
+}, "String constants from wasm:js/string-constants should be supported in ESM integration");