module: use Wasm CJS lexer when available

guybedford · MylesBorins · commit cb2f6ffd3e0a · 2020-10-14T16:21:25.000-04:00
PR-URL: #35583 Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: Geoffrey Booth <webmaster@geoffreybooth.com>
diff --git a/benchmark/esm/cjs-parse.js b/benchmark/esm/cjs-parse.js
@@ -0,0 +1,40 @@
+'use strict';
+const fs = require('fs');
+const path = require('path');
+const common = require('../common.js');
+const{strictEqual } = require('assert');
+
+const tmpdir = require('../../test/common/tmpdir');
+const benchmarkDirectory =
+ path.resolve(tmpdir.path, 'benchmark-esm-parse');
+
+const bench = common.createBenchmark(main,{
+ n: [1e2]
+});
+
+async function main({n }){
+ tmpdir.refresh();
+
+ fs.mkdirSync(benchmarkDirectory);
+
+ let sampleSource = 'try{\n';
+ for (let i = 0; i < 1000; i++){
+ sampleSource += 'sample.js(() => file = /test/);\n';
+ }
+ sampleSource += '} catch{}\nexports.p = 5;\n';
+
+ for (let i = 0; i < n; i++){
+ const sampleFile = path.join(benchmarkDirectory, `sample${i}.js`);
+ fs.writeFileSync(sampleFile, sampleSource);
+ }
+
+ bench.start();
+ for (let i = 0; i < n; i++){
+ const sampleFile = path.join(benchmarkDirectory, `sample${i}.js`);
+ const m = await import('file:' + sampleFile);
+ strictEqual(m.p, 5);
+ }
+ bench.end(n);
+
+ tmpdir.refresh();
+}
diff --git a/deps/cjs-module-lexer/dist/lexer.js b/deps/cjs-module-lexer/dist/lexer.js
diff --git a/deps/cjs-module-lexer/dist/lexer.mjs b/deps/cjs-module-lexer/dist/lexer.mjs
diff --git a/lib/internal/modules/esm/translators.js b/lib/internal/modules/esm/translators.js
@@ -56,9 +56,26 @@ const{getOptionValue } = require('internal/options');
 const experimentalImportMetaResolve =
 getOptionValue('--experimental-import-meta-resolve');
 const asyncESM = require('internal/process/esm_loader');
-const cjsParse = require('internal/deps/cjs-module-lexer/lexer');
 const{emitWarningSync } = require('internal/process/warning');
 
+let cjsParse;
+async function initCJSParse(){
+ if (typeof WebAssembly !== 'undefined'){
+ const{parse, init } =
+ require('internal/deps/cjs-module-lexer/dist/lexer');
+ await init();
+ let exports;
+ try{
+ ({exports } = parse('exports.a=1'));
+ if (exports.length === 1){
+ cjsParse = parse;
+ return;
+ }
+ } catch{}
+ }
+ cjsParse = require('internal/deps/cjs-module-lexer/lexer');
+}
+
 const translators = new SafeMap();
 exports.translators = translators;
 exports.enrichCJSError = enrichCJSError;
@@ -164,6 +181,7 @@ translators.set('commonjs', async function commonjsStrategy(url, isMain){
 if (isWindows)
 filename = StringPrototypeReplace(filename, winSepRegEx, '\\');
 
+ if (!cjsParse) await initCJSParse();
 const{module, exportNames } = cjsPreparseModuleExports(filename);
 const namesWithDefault = exportNames.has('default') ?
 [...exportNames] : ['default', ...exportNames];
diff --git a/node.gyp b/node.gyp
@@ -253,6 +253,7 @@
 'deps/acorn-plugins/acorn-private-methods/index.js',
 'deps/acorn-plugins/acorn-static-class-features/index.js',
 'deps/cjs-module-lexer/lexer.js',
+ 'deps/cjs-module-lexer/dist/lexer.js',
 ],
 'node_mksnapshot_exec': '<(PRODUCT_DIR)/<(EXECUTABLE_PREFIX)node_mksnapshot<(EXECUTABLE_SUFFIX)',
 'mkcodecache_exec': '<(PRODUCT_DIR)/<(EXECUTABLE_PREFIX)mkcodecache<(EXECUTABLE_SUFFIX)',
diff --git a/test/benchmark/test-benchmark-esm.js b/test/benchmark/test-benchmark-esm.js
@@ -0,0 +1,7 @@
+'use strict';
+
+require('../common');
+
+const runBenchmark = require('../common/benchmark');
+
+runBenchmark('esm',{NODEJS_BENCHMARK_ZERO_ALLOWED: 1 });
diff --git a/test/parallel/test-bootstrap-modules.js b/test/parallel/test-bootstrap-modules.js
@@ -53,7 +53,6 @@ const expectedModules = new Set([
 'NativeModule internal/modules/cjs/helpers',
 'NativeModule internal/modules/cjs/loader',
 'NativeModule internal/modules/esm/create_dynamic_module',
- 'NativeModule internal/deps/cjs-module-lexer/lexer',
 'NativeModule internal/modules/esm/get_format',
 'NativeModule internal/modules/esm/get_source',
 'NativeModule internal/modules/esm/loader',

-Original file line number
+Diff line change
@@ @@ -0,0 +1,40 @@ @@
 +'use strict';
 +constfs=require('fs');
 +constpath=require('path');
 +constcommon=require('../common.js');
 +const{ strictEqual }=require('assert');
++
 +consttmpdir=require('../../test/common/tmpdir');
 +constbenchmarkDirectory=
 +path.resolve(tmpdir.path,'benchmark-esm-parse');
++
 +constbench=common.createBenchmark(main,{
 +n: [1e2]
 +});
++
 +asyncfunctionmain({ n }){
 +tmpdir.refresh();
++
 +fs.mkdirSync(benchmarkDirectory);
++
 +letsampleSource='try{\n';
 +for(leti=0;i<1000;i++){
 +sampleSource+='sample.js(() => file = /test/);\n';
 +}
 +sampleSource+='} catch{}\nexports.p = 5;\n';
++
 +for(leti=0;i<n;i++){
 +constsampleFile=path.join(benchmarkDirectory,`sample${i}.js`);
 +fs.writeFileSync(sampleFile,sampleSource);
 +}
++
 +bench.start();
 +for(leti=0;i<n;i++){
 +constsampleFile=path.join(benchmarkDirectory,`sample${i}.js`);
 +constm=awaitimport('file:'+sampleFile);
 +strictEqual(m.p,5);
 +}
 +bench.end(n);
++
 +tmpdir.refresh();
 +}
-Original file line number
+Diff line change
 constexperimentalImportMetaResolve=
 getOptionValue('--experimental-import-meta-resolve');
 constasyncESM=require('internal/process/esm_loader');
 -constcjsParse=require('internal/deps/cjs-module-lexer/lexer');
 const{ emitWarningSync }=require('internal/process/warning');
 +letcjsParse;
 +asyncfunctioninitCJSParse(){
 +if(typeofWebAssembly!=='undefined'){
 +const{ parse, init }=
 +require('internal/deps/cjs-module-lexer/dist/lexer');
 +awaitinit();
 +letexports;
 +try{
 +({ exports }=parse('exports.a=1'));
 +if(exports.length===1){
 +cjsParse=parse;
 +return;
 +}
 +}catch{}
 +}
 +cjsParse=require('internal/deps/cjs-module-lexer/lexer');
 +}
++
 consttranslators=newSafeMap();
 exports.translators=translators;
 exports.enrichCJSError=enrichCJSError;
 if(isWindows)
 filename=StringPrototypeReplace(filename,winSepRegEx,'\\');
 +if(!cjsParse)awaitinitCJSParse();
 const{ module, exportNames }=cjsPreparseModuleExports(filename);
 constnamesWithDefault=exportNames.has('default') ?
 [...exportNames] : ['default', ...exportNames];