Fix #1130

.github/workflows/continuous-integration.yml

@@ -40,7 +40,7 @@ jobs:
       matrix:
         os: [ubuntu, windows]
         # Don't forget to add all new flavors to this list!
-        flavor: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
+        flavor: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13]
         include:
           # Node 10
           - flavor: 1
@@ -94,20 +94,27 @@ jobs:
             nodeFlag: 14
             typescript: next
             typescriptFlag: next
-          # Node 15
+          # Node 14.13.0
+          # To test ESM builtin module resolution immediately before a node behavioral change: https://github.com/TypeStrong/ts-node/issues/1130
           - flavor: 10
+            node: 14.13.0
+            nodeFlag: 14_13_0
+            typescript: latest
+            typescriptFlag: latest
+          # Node 15
+          - flavor: 11
             node: 15
             nodeFlag: 15
             typescript: latest
             typescriptFlag: latest
             downgradeNpm: true
-          - flavor: 11
+          - flavor: 12
             node: 15
             nodeFlag: 15
             typescript: 2.7
             typescriptFlag: 2_7
             downgradeNpm: true
-          - flavor: 12
+          - flavor: 13
             node: 15
             nodeFlag: 15
             typescript: next

dist-raw/node-esm-resolve-implementation.js

@@ -4,6 +4,18 @@
 // upstream changes and understand our modifications.
 'use strict';
 
+const [nodeMajor, nodeMinor, nodePatch] = process.versions.node.split('.').map(s => parseInt(s, 10))
+// Test for 14.13.1 or higher
+const builtinModuleProtocol = nodeMajor > 14 || (
+    nodeMajor === 14 && (
+      nodeMinor > 13 || (
+        nodeMinor === 13 && nodePatch > 0
+      )
+    )
+  )
+    ? 'node:'
+    : 'nodejs:';
+
 const {
   ArrayIsArray,
   JSONParse,
@@ -688,13 +700,13 @@ function defaultResolve(specifier, { parentURL } = {}, defaultResolveUnused) {
       };
     }
   } catch {}
-  if (parsed && parsed.protocol === 'nodejs:')
+  if (parsed && parsed.protocol === builtinModuleProtocol)
     return { url: specifier };
   if (parsed && parsed.protocol !== 'file:' && parsed.protocol !== 'data:')
     throw new ERR_UNSUPPORTED_ESM_URL_SCHEME();
   if (NativeModule.canBeRequiredByUsers(specifier)) {
     return {
-      url: 'nodejs:' + specifier
+      url: builtinModuleProtocol + specifier
     };
   }
   if (parentURL && StringPrototypeStartsWith(parentURL, 'data:')) {

tests/esm/index.ts

@@ -3,6 +3,10 @@ import {bar} from './bar.js'
 import {baz} from './baz.js'
 import {biff} from './biff.js'
 
+// Test import builtin modules
+import {readFileSync} from 'fs';
+if(typeof readFileSync !== 'function') throw new Error('failed to import builtin module')
+
 if(typeof module !== 'undefined') throw new Error('module should not exist in ESM')
 
 console.log(`${foo} ${bar} ${baz} ${biff}`)