409 lines
14 KiB
JavaScript
409 lines
14 KiB
JavaScript
/*
|
|
MIT License http://www.opensource.org/licenses/mit-license.php
|
|
Author Tobias Koppers @sokra
|
|
*/
|
|
|
|
"use strict";
|
|
|
|
const RuntimeGlobals = require("../RuntimeGlobals");
|
|
const formatLocation = require("../formatLocation");
|
|
const { evaluateToString } = require("../javascript/JavascriptParserHelpers");
|
|
const propertyAccess = require("../util/propertyAccess");
|
|
const CommonJsExportRequireDependency = require("./CommonJsExportRequireDependency");
|
|
const CommonJsExportsDependency = require("./CommonJsExportsDependency");
|
|
const CommonJsSelfReferenceDependency = require("./CommonJsSelfReferenceDependency");
|
|
const DynamicExports = require("./DynamicExports");
|
|
const HarmonyExports = require("./HarmonyExports");
|
|
const ModuleDecoratorDependency = require("./ModuleDecoratorDependency");
|
|
|
|
/** @typedef {import("estree").AssignmentExpression} AssignmentExpression */
|
|
/** @typedef {import("estree").CallExpression} CallExpression */
|
|
/** @typedef {import("estree").Expression} Expression */
|
|
/** @typedef {import("estree").Super} Super */
|
|
/** @typedef {import("../Dependency").DependencyLocation} DependencyLocation */
|
|
/** @typedef {import("../ModuleGraph")} ModuleGraph */
|
|
/** @typedef {import("../NormalModule")} NormalModule */
|
|
/** @typedef {import("../javascript/BasicEvaluatedExpression")} BasicEvaluatedExpression */
|
|
/** @typedef {import("../javascript/JavascriptParser")} JavascriptParser */
|
|
/** @typedef {import("../javascript/JavascriptParser").Range} Range */
|
|
/** @typedef {import("./CommonJsDependencyHelpers").CommonJSDependencyBaseKeywords} CommonJSDependencyBaseKeywords */
|
|
|
|
/**
|
|
* This function takes a generic expression and detects whether it is an ObjectExpression.
|
|
* This is used in the context of parsing CommonJS exports to get the value of the property descriptor
|
|
* when the `exports` object is assigned to `Object.defineProperty`.
|
|
*
|
|
* In CommonJS modules, the `exports` object can be assigned to `Object.defineProperty` and therefore
|
|
* webpack has to detect this case and get the value key of the property descriptor. See the following example
|
|
* for more information: https://astexplorer.net/#/gist/83ce51a4e96e59d777df315a6d111da6/8058ead48a1bb53c097738225db0967ef7f70e57
|
|
*
|
|
* This would be an example of a CommonJS module that exports an object with a property descriptor:
|
|
* ```js
|
|
* Object.defineProperty(exports, "__esModule", { value: true });
|
|
* exports.foo = void 0;
|
|
* exports.foo = "bar";
|
|
* ```
|
|
* @param {TODO} expr expression
|
|
* @returns {Expression | undefined} returns the value of property descriptor
|
|
*/
|
|
const getValueOfPropertyDescription = expr => {
|
|
if (expr.type !== "ObjectExpression") return;
|
|
for (const property of expr.properties) {
|
|
if (property.computed) continue;
|
|
const key = property.key;
|
|
if (key.type !== "Identifier" || key.name !== "value") continue;
|
|
return property.value;
|
|
}
|
|
};
|
|
|
|
/**
|
|
* The purpose of this function is to check whether an expression is a truthy literal or not. This is
|
|
* useful when parsing CommonJS exports, because CommonJS modules can export any value, including falsy
|
|
* values like `null` and `false`. However, exports should only be created if the exported value is truthy.
|
|
* @param {Expression} expr expression being checked
|
|
* @returns {boolean} true, when the expression is a truthy literal
|
|
*/
|
|
const isTruthyLiteral = expr => {
|
|
switch (expr.type) {
|
|
case "Literal":
|
|
return Boolean(expr.value);
|
|
case "UnaryExpression":
|
|
if (expr.operator === "!") return isFalsyLiteral(expr.argument);
|
|
}
|
|
return false;
|
|
};
|
|
|
|
/**
|
|
* The purpose of this function is to check whether an expression is a falsy literal or not. This is
|
|
* useful when parsing CommonJS exports, because CommonJS modules can export any value, including falsy
|
|
* values like `null` and `false`. However, exports should only be created if the exported value is truthy.
|
|
* @param {Expression} expr expression being checked
|
|
* @returns {boolean} true, when the expression is a falsy literal
|
|
*/
|
|
const isFalsyLiteral = expr => {
|
|
switch (expr.type) {
|
|
case "Literal":
|
|
return !expr.value;
|
|
case "UnaryExpression":
|
|
if (expr.operator === "!") return isTruthyLiteral(expr.argument);
|
|
}
|
|
return false;
|
|
};
|
|
|
|
/**
|
|
* @param {JavascriptParser} parser the parser
|
|
* @param {Expression} expr expression
|
|
* @returns {{ argument: BasicEvaluatedExpression, ids: string[] } | undefined} parsed call
|
|
*/
|
|
const parseRequireCall = (parser, expr) => {
|
|
const ids = [];
|
|
while (expr.type === "MemberExpression") {
|
|
if (expr.object.type === "Super") return;
|
|
if (!expr.property) return;
|
|
const prop = expr.property;
|
|
if (expr.computed) {
|
|
if (prop.type !== "Literal") return;
|
|
ids.push(`${prop.value}`);
|
|
} else {
|
|
if (prop.type !== "Identifier") return;
|
|
ids.push(prop.name);
|
|
}
|
|
expr = expr.object;
|
|
}
|
|
if (expr.type !== "CallExpression" || expr.arguments.length !== 1) return;
|
|
const callee = expr.callee;
|
|
if (
|
|
callee.type !== "Identifier" ||
|
|
parser.getVariableInfo(callee.name) !== "require"
|
|
) {
|
|
return;
|
|
}
|
|
const arg = expr.arguments[0];
|
|
if (arg.type === "SpreadElement") return;
|
|
const argValue = parser.evaluateExpression(arg);
|
|
return { argument: argValue, ids: ids.reverse() };
|
|
};
|
|
|
|
class CommonJsExportsParserPlugin {
|
|
/**
|
|
* @param {ModuleGraph} moduleGraph module graph
|
|
*/
|
|
constructor(moduleGraph) {
|
|
this.moduleGraph = moduleGraph;
|
|
}
|
|
|
|
/**
|
|
* @param {JavascriptParser} parser the parser
|
|
* @returns {void}
|
|
*/
|
|
apply(parser) {
|
|
const enableStructuredExports = () => {
|
|
DynamicExports.enable(parser.state);
|
|
};
|
|
|
|
/**
|
|
* @param {boolean} topLevel true, when the export is on top level
|
|
* @param {string[]} members members of the export
|
|
* @param {Expression | undefined} valueExpr expression for the value
|
|
* @returns {void}
|
|
*/
|
|
const checkNamespace = (topLevel, members, valueExpr) => {
|
|
if (!DynamicExports.isEnabled(parser.state)) return;
|
|
if (members.length > 0 && members[0] === "__esModule") {
|
|
if (valueExpr && isTruthyLiteral(valueExpr) && topLevel) {
|
|
DynamicExports.setFlagged(parser.state);
|
|
} else {
|
|
DynamicExports.setDynamic(parser.state);
|
|
}
|
|
}
|
|
};
|
|
/**
|
|
* @param {string=} reason reason
|
|
*/
|
|
const bailout = reason => {
|
|
DynamicExports.bailout(parser.state);
|
|
if (reason) bailoutHint(reason);
|
|
};
|
|
/**
|
|
* @param {string} reason reason
|
|
*/
|
|
const bailoutHint = reason => {
|
|
this.moduleGraph
|
|
.getOptimizationBailout(parser.state.module)
|
|
.push(`CommonJS bailout: ${reason}`);
|
|
};
|
|
|
|
// metadata //
|
|
parser.hooks.evaluateTypeof
|
|
.for("module")
|
|
.tap("CommonJsExportsParserPlugin", evaluateToString("object"));
|
|
parser.hooks.evaluateTypeof
|
|
.for("exports")
|
|
.tap("CommonJsPlugin", evaluateToString("object"));
|
|
|
|
// exporting //
|
|
|
|
/**
|
|
* @param {AssignmentExpression} expr expression
|
|
* @param {CommonJSDependencyBaseKeywords} base commonjs base keywords
|
|
* @param {string[]} members members of the export
|
|
* @returns {boolean | undefined} true, when the expression was handled
|
|
*/
|
|
const handleAssignExport = (expr, base, members) => {
|
|
if (HarmonyExports.isEnabled(parser.state)) return;
|
|
// Handle reexporting
|
|
const requireCall = parseRequireCall(parser, expr.right);
|
|
if (
|
|
requireCall &&
|
|
requireCall.argument.isString() &&
|
|
(members.length === 0 || members[0] !== "__esModule")
|
|
) {
|
|
enableStructuredExports();
|
|
// It's possible to reexport __esModule, so we must convert to a dynamic module
|
|
if (members.length === 0) DynamicExports.setDynamic(parser.state);
|
|
const dep = new CommonJsExportRequireDependency(
|
|
/** @type {Range} */ (expr.range),
|
|
null,
|
|
base,
|
|
members,
|
|
/** @type {string} */ (requireCall.argument.string),
|
|
requireCall.ids,
|
|
!parser.isStatementLevelExpression(expr)
|
|
);
|
|
dep.loc = /** @type {DependencyLocation} */ (expr.loc);
|
|
dep.optional = Boolean(parser.scope.inTry);
|
|
parser.state.module.addDependency(dep);
|
|
return true;
|
|
}
|
|
if (members.length === 0) return;
|
|
enableStructuredExports();
|
|
const remainingMembers = members;
|
|
checkNamespace(
|
|
parser.statementPath.length === 1 &&
|
|
parser.isStatementLevelExpression(expr),
|
|
remainingMembers,
|
|
expr.right
|
|
);
|
|
const dep = new CommonJsExportsDependency(
|
|
/** @type {Range} */ (expr.left.range),
|
|
null,
|
|
base,
|
|
remainingMembers
|
|
);
|
|
dep.loc = /** @type {DependencyLocation} */ (expr.loc);
|
|
parser.state.module.addDependency(dep);
|
|
parser.walkExpression(expr.right);
|
|
return true;
|
|
};
|
|
parser.hooks.assignMemberChain
|
|
.for("exports")
|
|
.tap("CommonJsExportsParserPlugin", (expr, members) =>
|
|
handleAssignExport(expr, "exports", members)
|
|
);
|
|
parser.hooks.assignMemberChain
|
|
.for("this")
|
|
.tap("CommonJsExportsParserPlugin", (expr, members) => {
|
|
if (!parser.scope.topLevelScope) return;
|
|
return handleAssignExport(expr, "this", members);
|
|
});
|
|
parser.hooks.assignMemberChain
|
|
.for("module")
|
|
.tap("CommonJsExportsParserPlugin", (expr, members) => {
|
|
if (members[0] !== "exports") return;
|
|
return handleAssignExport(expr, "module.exports", members.slice(1));
|
|
});
|
|
parser.hooks.call
|
|
.for("Object.defineProperty")
|
|
.tap("CommonJsExportsParserPlugin", expression => {
|
|
const expr = /** @type {CallExpression} */ (expression);
|
|
if (!parser.isStatementLevelExpression(expr)) return;
|
|
if (expr.arguments.length !== 3) return;
|
|
if (expr.arguments[0].type === "SpreadElement") return;
|
|
if (expr.arguments[1].type === "SpreadElement") return;
|
|
if (expr.arguments[2].type === "SpreadElement") return;
|
|
const exportsArg = parser.evaluateExpression(expr.arguments[0]);
|
|
if (!exportsArg.isIdentifier()) return;
|
|
if (
|
|
exportsArg.identifier !== "exports" &&
|
|
exportsArg.identifier !== "module.exports" &&
|
|
(exportsArg.identifier !== "this" || !parser.scope.topLevelScope)
|
|
) {
|
|
return;
|
|
}
|
|
const propertyArg = parser.evaluateExpression(expr.arguments[1]);
|
|
const property = propertyArg.asString();
|
|
if (typeof property !== "string") return;
|
|
enableStructuredExports();
|
|
const descArg = expr.arguments[2];
|
|
checkNamespace(
|
|
parser.statementPath.length === 1,
|
|
[property],
|
|
getValueOfPropertyDescription(descArg)
|
|
);
|
|
const dep = new CommonJsExportsDependency(
|
|
/** @type {Range} */ (expr.range),
|
|
/** @type {Range} */ (expr.arguments[2].range),
|
|
`Object.defineProperty(${exportsArg.identifier})`,
|
|
[property]
|
|
);
|
|
dep.loc = /** @type {DependencyLocation} */ (expr.loc);
|
|
parser.state.module.addDependency(dep);
|
|
|
|
parser.walkExpression(expr.arguments[2]);
|
|
return true;
|
|
});
|
|
|
|
// Self reference //
|
|
|
|
/**
|
|
* @param {Expression | Super} expr expression
|
|
* @param {CommonJSDependencyBaseKeywords} base commonjs base keywords
|
|
* @param {string[]} members members of the export
|
|
* @param {CallExpression=} call call expression
|
|
* @returns {boolean | void} true, when the expression was handled
|
|
*/
|
|
const handleAccessExport = (expr, base, members, call) => {
|
|
if (HarmonyExports.isEnabled(parser.state)) return;
|
|
if (members.length === 0) {
|
|
bailout(
|
|
`${base} is used directly at ${formatLocation(
|
|
/** @type {DependencyLocation} */ (expr.loc)
|
|
)}`
|
|
);
|
|
}
|
|
if (call && members.length === 1) {
|
|
bailoutHint(
|
|
`${base}${propertyAccess(
|
|
members
|
|
)}(...) prevents optimization as ${base} is passed as call context at ${formatLocation(
|
|
/** @type {DependencyLocation} */ (expr.loc)
|
|
)}`
|
|
);
|
|
}
|
|
const dep = new CommonJsSelfReferenceDependency(
|
|
/** @type {Range} */ (expr.range),
|
|
base,
|
|
members,
|
|
Boolean(call)
|
|
);
|
|
dep.loc = /** @type {DependencyLocation} */ (expr.loc);
|
|
parser.state.module.addDependency(dep);
|
|
if (call) {
|
|
parser.walkExpressions(call.arguments);
|
|
}
|
|
return true;
|
|
};
|
|
parser.hooks.callMemberChain
|
|
.for("exports")
|
|
.tap("CommonJsExportsParserPlugin", (expr, members) =>
|
|
handleAccessExport(expr.callee, "exports", members, expr)
|
|
);
|
|
parser.hooks.expressionMemberChain
|
|
.for("exports")
|
|
.tap("CommonJsExportsParserPlugin", (expr, members) =>
|
|
handleAccessExport(expr, "exports", members)
|
|
);
|
|
parser.hooks.expression
|
|
.for("exports")
|
|
.tap("CommonJsExportsParserPlugin", expr =>
|
|
handleAccessExport(expr, "exports", [])
|
|
);
|
|
parser.hooks.callMemberChain
|
|
.for("module")
|
|
.tap("CommonJsExportsParserPlugin", (expr, members) => {
|
|
if (members[0] !== "exports") return;
|
|
return handleAccessExport(
|
|
expr.callee,
|
|
"module.exports",
|
|
members.slice(1),
|
|
expr
|
|
);
|
|
});
|
|
parser.hooks.expressionMemberChain
|
|
.for("module")
|
|
.tap("CommonJsExportsParserPlugin", (expr, members) => {
|
|
if (members[0] !== "exports") return;
|
|
return handleAccessExport(expr, "module.exports", members.slice(1));
|
|
});
|
|
parser.hooks.expression
|
|
.for("module.exports")
|
|
.tap("CommonJsExportsParserPlugin", expr =>
|
|
handleAccessExport(expr, "module.exports", [])
|
|
);
|
|
parser.hooks.callMemberChain
|
|
.for("this")
|
|
.tap("CommonJsExportsParserPlugin", (expr, members) => {
|
|
if (!parser.scope.topLevelScope) return;
|
|
return handleAccessExport(expr.callee, "this", members, expr);
|
|
});
|
|
parser.hooks.expressionMemberChain
|
|
.for("this")
|
|
.tap("CommonJsExportsParserPlugin", (expr, members) => {
|
|
if (!parser.scope.topLevelScope) return;
|
|
return handleAccessExport(expr, "this", members);
|
|
});
|
|
parser.hooks.expression
|
|
.for("this")
|
|
.tap("CommonJsExportsParserPlugin", expr => {
|
|
if (!parser.scope.topLevelScope) return;
|
|
return handleAccessExport(expr, "this", []);
|
|
});
|
|
|
|
// Bailouts //
|
|
parser.hooks.expression.for("module").tap("CommonJsPlugin", expr => {
|
|
bailout();
|
|
const isHarmony = HarmonyExports.isEnabled(parser.state);
|
|
const dep = new ModuleDecoratorDependency(
|
|
isHarmony
|
|
? RuntimeGlobals.harmonyModuleDecorator
|
|
: RuntimeGlobals.nodeModuleDecorator,
|
|
!isHarmony
|
|
);
|
|
dep.loc = /** @type {DependencyLocation} */ (expr.loc);
|
|
parser.state.module.addDependency(dep);
|
|
return true;
|
|
});
|
|
}
|
|
}
|
|
module.exports = CommonJsExportsParserPlugin;
|