test,esm: validate more edge cases for dynamic imports

test/es-module/test-esm-loader-hooks.mjs

@@ -4,7 +4,7 @@ import assert from 'node:assert';
 import { execPath } from 'node:process';
 import { describe, it } from 'node:test';
 
-describe('Loader hooks', () => {
+describe('Loader hooks', { concurrency: true }, () => {
   it('are called with all expected arguments', async () => {
     const { code, signal, stdout, stderr } = await spawnPromisified(execPath, [
       '--no-warnings',
@@ -23,4 +23,88 @@ describe('Loader hooks', () => {
     assert.match(lines[2], /{"url":"file:\/\/\/.*\/experimental\.json","format":"test","shortCircuit":true}/);
     assert.match(lines[3], /{"source":{"type":"Buffer","data":\[.*\]},"format":"json","shortCircuit":true}/);
   });
+
+  it('should be able to handle never resolving dynamic imports (ESM entry point)', async () => {
+    const { code, signal, stdout, stderr } = await spawnPromisified(execPath, [
+      '--no-warnings',
+      '--experimental-loader',
+      fixtures.fileURL('es-module-loaders/never-settling-resolve-step/loader.mjs'),
+      fixtures.path('es-module-loaders/never-settling-resolve-step/never-resolve.mjs'),
+    ]);
+
+    assert.strictEqual(stderr, '');
+    assert.match(stdout, /^should be output\r?\n$/);
+    assert.strictEqual(code, 13);
+    assert.strictEqual(signal, null);
+  });
+
+  it('should be able to handle never resolving dynamic imports (CJS entry point)', async () => {
+    const { code, signal, stdout, stderr } = await spawnPromisified(execPath, [
+      '--no-warnings',
+      '--experimental-loader',
+      fixtures.fileURL('es-module-loaders/never-settling-resolve-step/loader.mjs'),
+      fixtures.path('es-module-loaders/never-settling-resolve-step/never-resolve.cjs'),
+    ]);
+
+    assert.strictEqual(stderr, '');
+    assert.match(stdout, /^should be output\r?\n$/);
+    assert.strictEqual(code, 0);
+    assert.strictEqual(signal, null);
+  });
+
+  it('should be able to handle never loading dynamic imports (ESM entry point)', async () => {
+    const { code, signal, stdout, stderr } = await spawnPromisified(execPath, [
+      '--no-warnings',
+      '--experimental-loader',
+      fixtures.fileURL('es-module-loaders/never-settling-resolve-step/loader.mjs'),
+      fixtures.path('es-module-loaders/never-settling-resolve-step/never-load.mjs'),
+    ]);
+
+    assert.strictEqual(stderr, '');
+    assert.match(stdout, /^should be output\r?\n$/);
+    assert.strictEqual(code, 13);
+    assert.strictEqual(signal, null);
+  });
+
+  it('should be able to handle never loading dynamic imports (CJS entry point)', async () => {
+    const { code, signal, stdout, stderr } = await spawnPromisified(execPath, [
+      '--no-warnings',
+      '--experimental-loader',
+      fixtures.fileURL('es-module-loaders/never-settling-resolve-step/loader.mjs'),
+      fixtures.path('es-module-loaders/never-settling-resolve-step/never-load.cjs'),
+    ]);
+
+    assert.strictEqual(stderr, '');
+    assert.match(stdout, /^should be output\r?\n$/);
+    assert.strictEqual(code, 0);
+    assert.strictEqual(signal, null);
+  });
+
+  it('should be able to handle race of never settling dynamic imports (ESM entry point)', async () => {
+    const { code, signal, stdout, stderr } = await spawnPromisified(execPath, [
+      '--no-warnings',
+      '--experimental-loader',
+      fixtures.fileURL('es-module-loaders/never-settling-resolve-step/loader.mjs'),
+      fixtures.path('es-module-loaders/never-settling-resolve-step/race.mjs'),
+    ]);
+
+    assert.strictEqual(stderr, '');
+    assert.match(stdout, /^true\r?\n$/);
+    assert.strictEqual(code, 0);
+    assert.strictEqual(signal, null);
+  });
+
+  it('should be able to handle race of never settling dynamic imports (CJS entry point)', async () => {
+    const { code, signal, stdout, stderr } = await spawnPromisified(execPath, [
+      '--no-warnings',
+      '--experimental-loader',
+      fixtures.fileURL('es-module-loaders/never-settling-resolve-step/loader.mjs'),
+      fixtures.path('es-module-loaders/never-settling-resolve-step/race.cjs'),
+    ]);
+
+    assert.strictEqual(stderr, '');
+    assert.match(stdout, /^true\r?\n$/);
+    assert.strictEqual(code, 0);
+    assert.strictEqual(signal, null);
+  });
 });

test/fixtures/es-module-loaders/never-settling-resolve-step/loader.mjs

@@ -0,0 +1,10 @@
+export function resolve(specifier, context, next) {
+    if (specifier === 'never-settle-resolve') return new Promise(() => {});
+    if (specifier === 'never-settle-load') return { __proto__: null, shortCircuit: true, url: 'never-settle:///' };
+    return next(specifier, context);
+}
+
+export function load(url, context, next) {
+    if (url === 'never-settle:///') return new Promise(() => {});
+    return next(url, context);
+}

test/fixtures/es-module-loaders/never-settling-resolve-step/never-load.cjs

@@ -0,0 +1,7 @@
+'use strict';
+
+const neverSettlingDynamicImport = import('never-settle-load');
+
+console.log('should be output');
+
+neverSettlingDynamicImport.then(() => process.exit(1));

test/fixtures/es-module-loaders/never-settling-resolve-step/never-load.mjs

@@ -0,0 +1,5 @@
+const neverSettlingDynamicImport = import('never-settle-load');
+
+console.log('should be output');
+
+await neverSettlingDynamicImport;

test/fixtures/es-module-loaders/never-settling-resolve-step/never-resolve.cjs

@@ -0,0 +1,7 @@
+'use strict';
+
+const neverSettlingDynamicImport = import('never-settle-resolve');
+
+console.log('should be output');
+
+neverSettlingDynamicImport.then(() => process.exit(1));

test/fixtures/es-module-loaders/never-settling-resolve-step/never-resolve.mjs

@@ -0,0 +1,5 @@
+const neverSettlingDynamicImport = import('never-settle-resolve');
+
+console.log('should be output');
+
+await neverSettlingDynamicImport;

test/fixtures/es-module-loaders/never-settling-resolve-step/race.cjs

@@ -0,0 +1,7 @@
+'use strict';
+
+Promise.race([
+    import('never-settle-resolve'),
+    import('never-settle-load'),
+    import('node:process'),
+]).then(result => console.log(result.default === process));

test/fixtures/es-module-loaders/never-settling-resolve-step/race.mjs

@@ -0,0 +1,7 @@
+const result = await Promise.race([
+    import('never-settle-resolve'),
+    import('never-settle-load'),
+    import('node:process'),
+]);
+
+console.log(result.default === process);