diff options
Diffstat (limited to 'node_modules/webpack/lib/ConstPlugin.js')
| -rw-r--r-- | node_modules/webpack/lib/ConstPlugin.js | 348 |
1 files changed, 0 insertions, 348 deletions
diff --git a/node_modules/webpack/lib/ConstPlugin.js b/node_modules/webpack/lib/ConstPlugin.js deleted file mode 100644 index 6b05720..0000000 --- a/node_modules/webpack/lib/ConstPlugin.js +++ /dev/null @@ -1,348 +0,0 @@ -/* - MIT License http://www.opensource.org/licenses/mit-license.php - Author Tobias Koppers @sokra -*/ -"use strict"; -const ConstDependency = require("./dependencies/ConstDependency"); -const NullFactory = require("./NullFactory"); -const ParserHelpers = require("./ParserHelpers"); - -const getQuery = request => { - const i = request.indexOf("?"); - return i !== -1 ? request.substr(i) : ""; -}; - -const collectDeclaration = (declarations, pattern) => { - const stack = [pattern]; - while (stack.length > 0) { - const node = stack.pop(); - switch (node.type) { - case "Identifier": - declarations.add(node.name); - break; - case "ArrayPattern": - for (const element of node.elements) { - if (element) { - stack.push(element); - } - } - break; - case "AssignmentPattern": - stack.push(node.left); - break; - case "ObjectPattern": - for (const property of node.properties) { - stack.push(property.value); - } - break; - case "RestElement": - stack.push(node.argument); - break; - } - } -}; - -const getHoistedDeclarations = (branch, includeFunctionDeclarations) => { - const declarations = new Set(); - const stack = [branch]; - while (stack.length > 0) { - const node = stack.pop(); - // Some node could be `null` or `undefined`. - if (!node) continue; - switch (node.type) { - // Walk through control statements to look for hoisted declarations. - // Some branches are skipped since they do not allow declarations. - case "BlockStatement": - for (const stmt of node.body) { - stack.push(stmt); - } - break; - case "IfStatement": - stack.push(node.consequent); - stack.push(node.alternate); - break; - case "ForStatement": - stack.push(node.init); - stack.push(node.body); - break; - case "ForInStatement": - case "ForOfStatement": - stack.push(node.left); - stack.push(node.body); - break; - case "DoWhileStatement": - case "WhileStatement": - case "LabeledStatement": - stack.push(node.body); - break; - case "SwitchStatement": - for (const cs of node.cases) { - for (const consequent of cs.consequent) { - stack.push(consequent); - } - } - break; - case "TryStatement": - stack.push(node.block); - if (node.handler) { - stack.push(node.handler.body); - } - stack.push(node.finalizer); - break; - case "FunctionDeclaration": - if (includeFunctionDeclarations) { - collectDeclaration(declarations, node.id); - } - break; - case "VariableDeclaration": - if (node.kind === "var") { - for (const decl of node.declarations) { - collectDeclaration(declarations, decl.id); - } - } - break; - } - } - return Array.from(declarations); -}; - -class ConstPlugin { - apply(compiler) { - compiler.hooks.compilation.tap( - "ConstPlugin", - (compilation, { normalModuleFactory }) => { - compilation.dependencyFactories.set(ConstDependency, new NullFactory()); - compilation.dependencyTemplates.set( - ConstDependency, - new ConstDependency.Template() - ); - - const handler = parser => { - parser.hooks.statementIf.tap("ConstPlugin", statement => { - if (parser.scope.isAsmJs) return; - const param = parser.evaluateExpression(statement.test); - const bool = param.asBool(); - if (typeof bool === "boolean") { - if (statement.test.type !== "Literal") { - const dep = new ConstDependency(`${bool}`, param.range); - dep.loc = statement.loc; - parser.state.current.addDependency(dep); - } - const branchToRemove = bool - ? statement.alternate - : statement.consequent; - if (branchToRemove) { - // Before removing the dead branch, the hoisted declarations - // must be collected. - // - // Given the following code: - // - // if (true) f() else g() - // if (false) { - // function f() {} - // const g = function g() {} - // if (someTest) { - // let a = 1 - // var x, {y, z} = obj - // } - // } else { - // … - // } - // - // the generated code is: - // - // if (true) f() else {} - // if (false) { - // var f, x, y, z; (in loose mode) - // var x, y, z; (in strict mode) - // } else { - // … - // } - // - // NOTE: When code runs in strict mode, `var` declarations - // are hoisted but `function` declarations don't. - // - let declarations; - if (parser.scope.isStrict) { - // If the code runs in strict mode, variable declarations - // using `var` must be hoisted. - declarations = getHoistedDeclarations(branchToRemove, false); - } else { - // Otherwise, collect all hoisted declaration. - declarations = getHoistedDeclarations(branchToRemove, true); - } - let replacement; - if (declarations.length > 0) { - replacement = `{ var ${declarations.join(", ")}; }`; - } else { - replacement = "{}"; - } - const dep = new ConstDependency( - replacement, - branchToRemove.range - ); - dep.loc = branchToRemove.loc; - parser.state.current.addDependency(dep); - } - return bool; - } - }); - parser.hooks.expressionConditionalOperator.tap( - "ConstPlugin", - expression => { - if (parser.scope.isAsmJs) return; - const param = parser.evaluateExpression(expression.test); - const bool = param.asBool(); - if (typeof bool === "boolean") { - if (expression.test.type !== "Literal") { - const dep = new ConstDependency(` ${bool}`, param.range); - dep.loc = expression.loc; - parser.state.current.addDependency(dep); - } - // Expressions do not hoist. - // It is safe to remove the dead branch. - // - // Given the following code: - // - // false ? someExpression() : otherExpression(); - // - // the generated code is: - // - // false ? undefined : otherExpression(); - // - const branchToRemove = bool - ? expression.alternate - : expression.consequent; - const dep = new ConstDependency( - "undefined", - branchToRemove.range - ); - dep.loc = branchToRemove.loc; - parser.state.current.addDependency(dep); - return bool; - } - } - ); - parser.hooks.expressionLogicalOperator.tap( - "ConstPlugin", - expression => { - if (parser.scope.isAsmJs) return; - if ( - expression.operator === "&&" || - expression.operator === "||" - ) { - const param = parser.evaluateExpression(expression.left); - const bool = param.asBool(); - if (typeof bool === "boolean") { - // Expressions do not hoist. - // It is safe to remove the dead branch. - // - // ------------------------------------------ - // - // Given the following code: - // - // falsyExpression() && someExpression(); - // - // the generated code is: - // - // falsyExpression() && false; - // - // ------------------------------------------ - // - // Given the following code: - // - // truthyExpression() && someExpression(); - // - // the generated code is: - // - // true && someExpression(); - // - // ------------------------------------------ - // - // Given the following code: - // - // truthyExpression() || someExpression(); - // - // the generated code is: - // - // truthyExpression() || false; - // - // ------------------------------------------ - // - // Given the following code: - // - // falsyExpression() || someExpression(); - // - // the generated code is: - // - // false && someExpression(); - // - const keepRight = - (expression.operator === "&&" && bool) || - (expression.operator === "||" && !bool); - - if (param.isBoolean() || keepRight) { - // for case like - // - // return'development'===process.env.NODE_ENV&&'foo' - // - // we need a space before the bool to prevent result like - // - // returnfalse&&'foo' - // - const dep = new ConstDependency(` ${bool}`, param.range); - dep.loc = expression.loc; - parser.state.current.addDependency(dep); - } else { - parser.walkExpression(expression.left); - } - if (!keepRight) { - const dep = new ConstDependency( - "false", - expression.right.range - ); - dep.loc = expression.loc; - parser.state.current.addDependency(dep); - } - return keepRight; - } - } - } - ); - parser.hooks.evaluateIdentifier - .for("__resourceQuery") - .tap("ConstPlugin", expr => { - if (parser.scope.isAsmJs) return; - if (!parser.state.module) return; - return ParserHelpers.evaluateToString( - getQuery(parser.state.module.resource) - )(expr); - }); - parser.hooks.expression - .for("__resourceQuery") - .tap("ConstPlugin", () => { - if (parser.scope.isAsmJs) return; - if (!parser.state.module) return; - parser.state.current.addVariable( - "__resourceQuery", - JSON.stringify(getQuery(parser.state.module.resource)) - ); - return true; - }); - }; - - normalModuleFactory.hooks.parser - .for("javascript/auto") - .tap("ConstPlugin", handler); - normalModuleFactory.hooks.parser - .for("javascript/dynamic") - .tap("ConstPlugin", handler); - normalModuleFactory.hooks.parser - .for("javascript/esm") - .tap("ConstPlugin", handler); - } - ); - } -} - -module.exports = ConstPlugin; |