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How to use genFunctionPreamble method in Playwright Internal
Best JavaScript code snippet using playwright-internal
note-generate-code.js
Source:note-generate-code.js 
...143 const hasHelpers = ast.helpers.length > 0;144 const useWithBlock = !prefixIdentifiers && mode !== 'module';145 // preambles146 {147 genFunctionPreamble(ast, context);148 }149 // binding optimizations150 const optimizeSources = options.bindingMetadata151 ? `, $props, $setup, $data, $options`152 : ``;153 // enter render function154 // 1. æ®é155 // function render(_ctx, _cache, $props, $setup, $data, $options){ããã}156 if (!ssr) {157 push(`function render(_ctx, _cache${optimizeSources}) {`);158 }159 // 2. ssr160 // function ssrRender(_ctx, _push, _parent, _attrs, $props, $setup, $data, $options){ããã}161 else {162 push(`function ssrRender(_ctx, _push, _parent, _attrs${optimizeSources}) {`);163 }164 indent();165 // é»è®¤ï¼mode = 'function'166 if (useWithBlock) {167 push(`with (_ctx) {`);168 indent();169 // function mode const declarations should be inside with block170 // also they should be renamed to avoid collision with user properties171 if (hasHelpers) {172 push(`const { ${ast.helpers173 .map(s => `${helperNameMap[s]}: _${helperNameMap[s]}`)174 .join(', ')} } = _Vue`);175 push(`\n`);176 newline();177 }178 }179 // generate asset resolution statements180 if (ast.components.length) {181 genAssets(ast.components, 'component', context);182 if (ast.directives.length || ast.temps > 0) {183 newline();184 }185 }186 if (ast.directives.length) {187 genAssets(ast.directives, 'directive', context);188 if (ast.temps > 0) {189 newline();190 }191 }192 if (ast.temps > 0) {193 push(`let `);194 for (let i = 0; i < ast.temps; i++) {195 push(`${i > 0 ? `, ` : ``}_temp${i}`);196 }197 }198 if (ast.components.length || ast.directives.length || ast.temps) {199 push(`\n`);200 newline();201 }202 // generate the VNode tree expression203 if (!ssr) {204 push(`return `);205 }206 if (ast.codegenNode) {207 genNode(ast.codegenNode, context);208 }209 else {210 push(`null`);211 }212 if (useWithBlock) {213 deindent();214 push(`}`);215 }216 deindent();217 push(`}`);218 return {219 ast,220 code: context.code,221 // SourceMapGenerator does have toJSON() method but it's not in the types222 map: context.map ? context.map.toJSON() : undefined223 };224}225 const PURE_ANNOTATION = `/*#__PURE__*/`;226 function createCodegenContext(ast, { 227 mode = 'function', 228 prefixIdentifiers = mode === 'module', 229 sourceMap = false, 230 filename = `template.vue.html`, 231 scopeId = null, 232 optimizeImports = false, 233 runtimeGlobalName = `Vue`, 234 runtimeModuleName = `vue`, 235 ssr = false 236 }) {237 const context = {238 mode,239 prefixIdentifiers,240 sourceMap,241 filename,242 scopeId,243 optimizeImports,244 runtimeGlobalName,245 runtimeModuleName,246 ssr,247 source: ast.loc.source,248 code: ``,249 column: 1,250 line: 1,251 offset: 0,252 indentLevel: 0,253 pure: false,254 map: undefined,255 helper(key) {256 return `_${helperNameMap[key]}`;257 },258 push(code, node) {259 context.code += code;260 },261 indent() {262 newline(++context.indentLevel);263 },264 deindent(withoutNewLine = false) {265 if (withoutNewLine) {266 --context.indentLevel;267 }268 else {269 newline(--context.indentLevel);270 }271 },272 newline() {273 newline(context.indentLevel);274 }275 };276 function newline(n) {277 context.push('\n' + ` `.repeat(n));278 }279 return context;280 }281 function genFunctionPreamble(ast, context) {282 const { ssr, prefixIdentifiers, push, newline, runtimeModuleName, runtimeGlobalName } = context;283 const VueBinding = runtimeGlobalName;284 const aliasHelper = (s) => `${helperNameMap[s]}: _${helperNameMap[s]}`;285 // Generate const declaration for helpers286 // In prefix mode, we place the const declaration at top so it's done287 // only once; But if we not prefixing, we place the declaration inside the288 // with block so it doesn't incur the `in` check cost for every helper access.289 if (ast.helpers.length > 0) {290 {291 // "with" mode.292 // save Vue in a separate variable to avoid collision293 push(`const _Vue = ${VueBinding}\n`);294 // in "with" mode, helpers are declared inside the with block to avoid295 // has check cost, but hoists are lifted out of the function - we need...
mini-vue.esm.js
Source:mini-vue.esm.js
...965};966function generate(ast) {967 const context = createCodegenContext();968 const { push } = context;969 genFunctionPreamble(ast, context);970 const functionName = "render";971 const args = ["_ctx", "_cache"];972 push(`return `);973 const signature = args.join(', ');974 push(`function ${functionName}(${signature}){`);975 push(`return `);976 genNode(ast.codegenNode, context);977 push('}');978 return {979 code: context.code980 };981}982function genFunctionPreamble(ast, context) {983 const { push } = context;984 const VueBinging = 'Vue';985 const aliasHelpers = (i) => `${helperMapName[i]}: _${helperMapName[i]}`;986 if (ast.helpers.length > 0) {987 push(`const { ${ast.helpers.map(aliasHelpers).join(", ")} } = ${VueBinging}`);988 push('\n');989 }990}991function genNode(node, ctx) {992 if (!node)993 return;994 switch (node.type) {995 case "text" /* TEXT */:996 genText(node, ctx);...
guide-mini-vue.cjs.js
Source:guide-mini-vue.cjs.js
...854};855function generate(ast) {856 const context = createCodegenContext();857 const { push } = context;858 genFunctionPreamble(ast, context);859 const functionName = "render";860 const args = ["_ctx", "_cache"];861 const signature = args.join(", ");862 push(`function ${functionName}(${signature}){`);863 push("return ");864 genNode(ast.codegenNode, context);865 push("}");866 return {867 code: context.code,868 };869}870function genFunctionPreamble(ast, context) {871 const { push } = context;872 const VueBinging = "Vue";873 const aliasHelper = (s) => `${helperMapName[s]}:_${helperMapName[s]}`;874 if (ast.helpers.length > 0) {875 push(`const { ${ast.helpers.map(aliasHelper).join(", ")} } = ${VueBinging}`);876 }877 push("\n");878 push("return ");879}880function createCodegenContext() {881 const context = {882 code: "",883 push(source) {884 context.code += source;...
guide-mini-vue.esm.js
Source:guide-mini-vue.esm.js
...852};853function generate(ast) {854 const context = createCodegenContext();855 const { push } = context;856 genFunctionPreamble(ast, context);857 const functionName = "render";858 const args = ["_ctx", "_cache"];859 const signature = args.join(", ");860 push(`function ${functionName}(${signature}){`);861 push("return ");862 genNode(ast.codegenNode, context);863 push("}");864 return {865 code: context.code,866 };867}868function genFunctionPreamble(ast, context) {869 const { push } = context;870 const VueBinging = "Vue";871 const aliasHelper = (s) => `${helperMapName[s]}:_${helperMapName[s]}`;872 if (ast.helpers.length > 0) {873 push(`const { ${ast.helpers.map(aliasHelper).join(", ")} } = ${VueBinging}`);874 }875 push("\n");876 push("return ");877}878function createCodegenContext() {879 const context = {880 code: "",881 push(source) {882 context.code += source;...
genCode.js
Source:genCode.js
...85 // in setup() inline mode, the preamble is generated in a sub context86 // and returned separately.87 const preambleContext = context;88 {89 genFunctionPreamble(ast, preambleContext);90 }91 // enter render function92 const functionName = ssr ? `ssrRender` : `render`;93 const args = ssr ? ['_ctx', '_push', '_parent', '_attrs'] : ['_ctx', '_cache'];94 const signature = args.join(', ');95 {96 push(`function ${functionName}(${signature}) {`);97 }98 indent();99 if (useWithBlock) {100 push(`with (_ctx) {`);101 indent();102 // function mode const declarations should be inside with block103 // also they should be renamed to avoid collision with user properties104 if (!ast.helpers.includes(CREATE_VNODE)) {105 ast.helpers.push(CREATE_VNODE);106 }107 if (hasHelpers) {108 push(`const { ${ast.helpers.map((s) => `${helperNameMap[s]}: _${helperNameMap[s]}`).join(', ')} } = _Vue`);109 push(`\n`);110 newline();111 }112 }113 // generate asset resolution statements114 if (ast.components.length) {115 genAssets(ast.components, 'component', context);116 if (ast.directives.length || ast.temps > 0) {117 newline();118 }119 }120 if (ast.directives.length) {121 genAssets(ast.directives, 'directive', context);122 if (ast.temps > 0) {123 newline();124 }125 }126 if (ast.temps > 0) {127 push(`let `);128 for (let i = 0; i < ast.temps; i++) {129 push(`${i > 0 ? `, ` : ``}_temp${i}`);130 }131 }132 if (ast.components.length || ast.directives.length || ast.temps) {133 push(`\n`);134 newline();135 }136 // generate the VNode tree expression137 if (!ssr) {138 push(`return `);139 }140 if (ast.codegenNode) {141 genNode(ast.codegenNode, context);142 } else {143 push(`null`);144 }145 if (useWithBlock) {146 deindent();147 push(`}`);148 }149 deindent();150 push(`}`);151 return {152 ast,153 code: context.code,154 preamble: ``,155 // SourceMapGenerator does have toJSON() method but it's not in the types156 map: context.map ? context.map.toJSON() : undefined,157 };158}159function genFunctionPreamble(ast, context) {160 const { ssr, prefixIdentifiers, push, newline, runtimeModuleName, runtimeGlobalName } = context;161 const VueBinding = runtimeGlobalName;162 const aliasHelper = (s) => `${helperNameMap[s]}: _${helperNameMap[s]}`;163 // Generate const declaration for helpers164 // In prefix mode, we place the const declaration at top so it's done165 // only once; But if we not prefixing, we place the declaration inside the166 // with block so it doesn't incur the `in` check cost for every helper access.167 if (ast.helpers.length > 0) {168 {169 // "with" mode.170 // save Vue in a separate variable to avoid collision171 push(`const _Vue = ${VueBinding}\n`);172 // in "with" mode, helpers are declared inside the with block to avoid173 // has check cost, but hoists are lifted out of the function - we need...
codegen.js
Source:codegen.js
...95 // TODO preambles96 if (!__BROWSER__ && mode === "module") {97 // TODO genModulePreamble(ast, context, genScopeId)98 } else {99 genFunctionPreamble(ast, context);100 }101 if (genScopeId && !ssr) {102 push(`const render = ${PURE_ANNOTATION}_withId(`);103 }104 if (!ssr) {105 // å½æ°å£°æ106 push(`function render(_ctx, _cache) {`);107 } else {108 // TODO ssr render109 }110 indent();111 if (useWithBlock) {112 // use with(_ctx) { ...}113 push(`with (_ctx) {`);114 indent();115 // TODO hasHelpers116 if (hasHelpers) {117 // æ¯å¦ï¼æå¼å¤çæ¶ç¨å° TO_DISPLAY_STRING helper118 // 为äºé¿å
å½åå²çªï¼è¿éé½éè¦å°ä»ä»¬éå½å119 push(120 `const { ${ast.helpers121 .map((s) => `${helperNameMap[s]} : _${helperNameMap[s]}`)122 .join(", ")} } = _Vue`123 );124 push("\n");125 newline();126 }127 }128 // TODO ast.components ç»ä»¶å¤ç129 // TODO ast.directives æ令å¤ç130 // TODO ast.temps 临æ¶åéå¤ç131 // TODO æ¢è¡132 if (!ssr) {133 push(`return `);134 }135 // çæ代ç ç段136 if (ast.codegenNode) {137 genNode(ast.codegenNode, context);138 } else {139 push(`null`);140 }141 if (useWithBlock) {142 deindent();143 push(`}`);144 }145 deindent();146 push(`}`);147 if (genScopeId && !ssr) {148 push(`)`);149 }150 return {151 ast,152 code: context.code,153 map: "",154 };155}156function genFunctionPreamble(ast, context) {157 const {158 push,159 newline,160 ssr,161 runtimeGlobalName,162 runtimeModuleName,163 prefixIdentifiers,164 } = context;165 // TODO ...166 const VueBinding =167 !__BROWSER__ && ssr168 ? `require(${JSON.striingify(runtimeModuleName)})`169 : runtimeGlobalName;170 const aliasHelper = (s) => `${helperNameMap[s]}: _${helperNameMap[s]}`;...
05-generate.js
Source:05-generate.js
...18 // é¢è®¾ä»£ç ï¼moduleé£æ ¼ å°±æ¯importè¯å¥19 genModulePreamble(ast, preambleContext, genScopeId, isSetupInlined)20 } else {21 // é¢è®¾ä»£ç ï¼å½æ°é£æ ¼ å°±æ¯importè¯å¥22 genFunctionPreamble(ast, preambleContext)23 }24 // renderè¿æ¯ssrRender25 const functionName = ssr ? `ssrRender` : `render`26 const args = ssr ? ['_ctx', '_push', '_parent', '_attrs'] : ['_ctx', '_cache']27 if (!__BROWSER__ && options.bindingMetadata && !options.inline) {28 // binding optimization args29 args.push('$props', '$setup', '$data', '$options')30 }31 const signature =32 !__BROWSER__ && options.isTS33 ? args.map(arg => `${arg}: any`).join(',')34 : args.join(', ')35 36 if (isSetupInlined) {...
compiler_generateOne.md.f38fde88.lean.js
Source:compiler_generateOne.md.f38fde88.lean.js
1import { o as n, c as s, a } from './app.547ab472.js'2const t =3 '{"title":"generate 代ç çæ","description":"","frontmatter":{},"headers":[{"level":2,"title":"generate 代ç çæ","slug":"generate-代ç çæ"},{"level":2,"title":"createCodegenContext å建代ç çæä¸ä¸æ","slug":"createcodegencontext-å建代ç çæä¸ä¸æ"},{"level":2,"title":"å
·ä½å®ç°","slug":"å
·ä½å®ç°"},{"level":3,"title":"genFunctionPreamble çæå½æ°æ¹å¼","slug":"genfunctionpreamble-çæå½æ°æ¹å¼"}],"relativePath":"compiler/generateOne.md","lastUpdated":1641357564051}',4 p = {},5 o = a('', 11)6p.render = function(a, t, p, e, c, l) {7 return n(), s('div', null, [o])8}9export default p...
Using AI Code Generation
1const { genFunctionPreamble } = require('playwright/lib/utils/stackTrace');2const { test } = require('@playwright/test');3test('test', async ({ page }) => {4 const handle = await page.$('text=Get started');5 const stack = await handle.evaluateHandle(genFunctionPreamble);6 console.log(await stack.jsonValue());7});8### `genFunctionPreamble()`
Using AI Code Generation
1const { genFunctionPreamble } = require('playwright/lib/utils/stackTrace');2const { test } = require('@playwright/test');3test('test', async ({ page }) => {4 const frame = page.mainFrame();5 const func = () => frame.evaluate(() => {});6 const error = new Error();7 error.stack = error.stack.replace(8 genFunctionPreamble(func, 'test.js', 'test', 1)9 );10 console.log(error.stack);11});12Error: test (test.js:1:1)13 at test (test.js:1:1)14### `genFunctionPreamble(func, file, name, line)`
Using AI Code Generation
1const { genFunctionPreamble } = require('playwright/lib/server/frames');2const fs = require('fs');3const path = require('path');4const { promisify } = require('util');5const writeFile = promisify(fs.writeFile);6const filePath = path.join(__dirname, 'preamble.js');7const preamble = genFunctionPreamble('test', 'async', 'function');8writeFile(filePath, preamble);
Using AI Code Generation
1const { genFunctionPreamble } = require('playwright/lib/server/frames');2const { Frame } = require('playwright/lib/server/frames');3const { Page } = require('playwright/lib/server/page');4const { ElementHandle } = require('playwright/lib/server/dom');5const { JSHandle } = require('playwright/lib/server/jsHandle');6const page = new Page(null, null, null, null, null, null);7const frame = new Frame(page, null, null, null, null, null, null);8const elementHandle = new ElementHandle(frame, null, null, null, null, null, null);9const jsHandle = new JSHandle(elementHandle, null, null, null, null, null, null);10const functionString = 'function() { return 42; }';11const functionString2 = 'function() { return 42; }';12const functionString3 = 'function() { return 42; }';13const preamble = genFunctionPreamble(functionString, [], false, false, null);14const preamble2 = genFunctionPreamble(functionString2, [], false, false, null);15const preamble3 = genFunctionPreamble(functionString3, [], false, false, null);16console.log(preamble);17console.log(preamble2);18console.log(preamble3);19async function __pwFunction() {20 return 42;21}22async function __pwFunction() {23 return 42;24}25async function __pwFunction() {26 return 42;27}
Using AI Code Generation
1const { genFunctionPreamble } = require('playwright/lib/server/frames');2const { Page } = require('playwright');3const page = new Page();4const code = `console.log('hello world')`;5const preamble = genFunctionPreamble(code, [], { page });6console.log(preamble);7(async() => {8 const { page } = window;9 const context = page._frameManager._mainFrame._context;10 const console = context._consoleApi();11 const log = console.log.bind(console);12 await page._setFileChooserIntercepted(true);13 log('hello world');14})15const { genFunctionPreamble } = require('playwright-core/lib/server/frames');16const { Page } = require('playwright-core');17const page = new Page();18const code = `console.log('hello world')`;19const preamble = genFunctionPreamble(code, [], { page });20console.log(preamble);21(async() => {22 const { page } = window;23 const context = page._frameManager._mainFrame._context;24 const console = context._consoleApi();25 const log = console.log.bind(console);26 await page._setFileChooserIntercepted(true);27 log('hello world');28})29[MIT](
Using AI Code Generation
1const { Playwright } = require('playwright-core');2const { genFunctionPreamble } = Playwright._internal;3const func = () => {4 console.log('hello');5};6const funcString = func.toString();7const preamble = genFunctionPreamble(funcString);8console.log(preamble);9function anonymous(10) {11[Apache 2.0](
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