module: use buffer.toString base64

`btoa` only supports latin-1 charset and produces invalid source mapping urls. PR-URL: #56315 Refs: #56296 Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com> Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com> Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com> Reviewed-By: Colin Ihrig <cjihrig@gmail.com> Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

Author: legendecas

lib/eslint.config_partial.mjs

@@ -13,6 +13,15 @@ const noRestrictedSyntax = [
  selector: "CallExpression[callee.object.name='assert']:not([callee.property.name='ok']):not([callee.property.name='fail']):not([callee.property.name='ifError'])",
  message: 'Only use simple assertions',
  },
+ {
+ // Forbids usages of `btoa` that are not caught by no-restricted-globals, like:
+ // ```
+ // const { btoa } = internalBinding('buffer');
+ // btoa('...');
+ // ```
+ selector: "CallExpression[callee.property.name='btoa'], CallExpression[callee.name='btoa']",
+ message: "`btoa` supports only latin-1 charset, use Buffer.from(str).toString('base64') instead",
+ },
  {
  selector: 'NewExpression[callee.name=/Error$/]:not([callee.name=/^(AssertionError|NghttpError|AbortError|NodeAggregateError)$/])',
  message: "Use an error exported by 'internal/errors' instead.",

lib/internal/modules/typescript.js

@@ -17,6 +17,7 @@ const {
 } = require('internal/errors').codes;
 const { getOptionValue } = require('internal/options');
 const assert = require('internal/assert');
+const { Buffer } = require('buffer');
 
 /**
  * The TypeScript parsing mode, either 'strip-only' or 'transform'.
@@ -134,9 +135,10 @@ function stripTypeScriptModuleTypes(source, filename) {
  * @returns {string} The code with the source map attached.
  */
 function addSourceMap(code, sourceMap) {
- // TODO(@marco-ippolito) When Buffer.transcode supports utf8 to
- // base64 transformation, we should change this line.
- const base64SourceMap = internalBinding('buffer').btoa(sourceMap);
+ // The base64 encoding should be https://datatracker.ietf.org/doc/html/rfc4648#section-4,
+ // not base64url https://datatracker.ietf.org/doc/html/rfc4648#section-5. See data url
+ // spec https://tools.ietf.org/html/rfc2397#section-2.
+ const base64SourceMap = Buffer.from(sourceMap).toString('base64');
  return `${code}\n\n//# sourceMappingURL=data:application/json;base64,${base64SourceMap}`;
 }
 

test/parallel/test-module-strip-types.js

@@ -12,6 +12,12 @@ common.expectWarning(
  'stripTypeScriptTypes is an experimental feature and might change at any time',
 );
 
+const sourceToBeTransformed = `
+ namespace MathUtil {
+ export const add = (a: number, b: number) => a + b;
+ }`;
+const sourceToBeTransformedMapping = 'UACY;aACK,MAAM,CAAC,GAAW,IAAc,IAAI;AACnD,GAFU,aAAA';
+
 test('stripTypeScriptTypes', () => {
  const source = 'const x: number = 1;';
  const result = stripTypeScriptTypes(source);
@@ -48,45 +54,52 @@ test('stripTypeScriptTypes sourceUrl throws when mode is strip', () => {
 });
 
 test('stripTypeScriptTypes source map when mode is transform', () => {
- const source = `
- namespace MathUtil {
- export const add = (a: number, b: number) => a + b;
- }`;
- const result = stripTypeScriptTypes(source, { mode: 'transform', sourceMap: true });
+ const result = stripTypeScriptTypes(sourceToBeTransformed, { mode: 'transform', sourceMap: true });
  const script = new vm.Script(result);
  const sourceMap =
  {
  version: 3,
- sources: [
- '<anon>',
- ],
- sourcesContent: [
- '\n namespace MathUtil {\n export const add = (a: number, b: number) => a + b;\n }',
- ],
+ sources: [''],
  names: [],
- mappings: ';UACY;aACK,MAAM,CAAC,GAAW,IAAc,IAAI;AACnD,GAFU,aAAA'
+ mappings: sourceToBeTransformedMapping,
  };
- assert(script.sourceMapURL, `sourceMappingURL=data:application/json;base64,${JSON.stringify(sourceMap)}`);
+ const inlinedSourceMap = Buffer.from(JSON.stringify(sourceMap)).toString('base64');
+ assert.strictEqual(script.sourceMapURL, `data:application/json;base64,${inlinedSourceMap}`);
 });
 
 test('stripTypeScriptTypes source map when mode is transform and sourceUrl', () => {
- const source = `
- namespace MathUtil {
- export const add = (a: number, b: number) => a + b;
- }`;
- const result = stripTypeScriptTypes(source, { mode: 'transform', sourceMap: true, sourceUrl: 'test.ts' });
+ const result = stripTypeScriptTypes(sourceToBeTransformed, {
+ mode: 'transform',
+ sourceMap: true,
+ sourceUrl: 'test.ts'
+ });
+ const script = new vm.Script(result);
+ const sourceMap =
+ {
+ version: 3,
+ sources: ['test.ts'],
+ names: [],
+ mappings: sourceToBeTransformedMapping,
+ };
+ const inlinedSourceMap = Buffer.from(JSON.stringify(sourceMap)).toString('base64');
+ assert.strictEqual(script.sourceMapURL, `data:application/json;base64,${inlinedSourceMap}`);
+});
+
+test('stripTypeScriptTypes source map when mode is transform and sourceUrl with non-latin-1 chars', () => {
+ const sourceUrl = 'dir%20with $unusual"chars?\'åß∂ƒ©∆¬…`.cts';
+ const result = stripTypeScriptTypes(sourceToBeTransformed, {
+ mode: 'transform',
+ sourceMap: true,
+ sourceUrl,
+ });
  const script = new vm.Script(result);
  const sourceMap =
  {
  version: 3,
- sources: [
- 'test.ts',
- ],
- sourcesContent: [
- '\n namespace MathUtil {\n export const add = (a: number, b: number) => a + b;\n }',
- ],
+ sources: [sourceUrl],
  names: [],
- mappings: ';UACY;aACK,MAAM,CAAC,GAAW,IAAc,IAAI;AACnD,GAFU,aAAA'
+ mappings: sourceToBeTransformedMapping,
  };
- assert(script.sourceMapURL, `sourceMappingURL=data:application/json;base64,${JSON.stringify(sourceMap)}`);
+ const inlinedSourceMap = Buffer.from(JSON.stringify(sourceMap)).toString('base64');
+ assert.strictEqual(script.sourceMapURL, `data:application/json;base64,${inlinedSourceMap}`);
 });