webpack/lib/JavascriptParser.js

2456 lines
69 KiB
JavaScript

/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Tobias Koppers @sokra
*/
"use strict";
const { Parser } = require("acorn");
const { SyncBailHook, HookMap } = require("tapable");
const vm = require("vm");
const BasicEvaluatedExpression = require("./BasicEvaluatedExpression");
const StackedSetMap = require("./util/StackedSetMap");
// Syntax: https://developer.mozilla.org/en/SpiderMonkey/Parser_API
const parser = Parser.extend(
require("acorn-dynamic-import").default,
require("./parsing/importAwaitAcornPlugin")
);
const joinRanges = (startRange, endRange) => {
if (!endRange) return startRange;
if (!startRange) return endRange;
return [startRange[0], endRange[1]];
};
const defaultParserOptions = {
ranges: true,
locations: true,
ecmaVersion: 2019,
sourceType: "module",
allowAwaitOutsideFunction: true,
onComment: null
};
// regexp to match at lease one "magic comment"
const webpackCommentRegExp = new RegExp(/(^|\W)webpack[A-Z]{1,}[A-Za-z]{1,}:/);
const EMPTY_COMMENT_OPTIONS = {
options: null,
errors: null
};
class JavascriptParser {
constructor(options, sourceType = "auto") {
this.hooks = Object.freeze({
evaluateTypeof: new HookMap(() => new SyncBailHook(["expression"])),
evaluate: new HookMap(() => new SyncBailHook(["expression"])),
evaluateIdentifier: new HookMap(() => new SyncBailHook(["expression"])),
evaluateDefinedIdentifier: new HookMap(
() => new SyncBailHook(["expression"])
),
evaluateCallExpressionMember: new HookMap(
() => new SyncBailHook(["expression", "param"])
),
statement: new SyncBailHook(["statement"]),
statementIf: new SyncBailHook(["statement"]),
label: new HookMap(() => new SyncBailHook(["statement"])),
import: new SyncBailHook(["statement", "source"]),
importSpecifier: new SyncBailHook([
"statement",
"source",
"exportName",
"identifierName"
]),
export: new SyncBailHook(["statement"]),
exportImport: new SyncBailHook(["statement", "source"]),
exportDeclaration: new SyncBailHook(["statement", "declaration"]),
exportExpression: new SyncBailHook(["statement", "declaration"]),
exportSpecifier: new SyncBailHook([
"statement",
"identifierName",
"exportName",
"index"
]),
exportImportSpecifier: new SyncBailHook([
"statement",
"source",
"identifierName",
"exportName",
"index"
]),
varDeclaration: new HookMap(() => new SyncBailHook(["declaration"])),
varDeclarationLet: new HookMap(() => new SyncBailHook(["declaration"])),
varDeclarationConst: new HookMap(() => new SyncBailHook(["declaration"])),
varDeclarationVar: new HookMap(() => new SyncBailHook(["declaration"])),
pattern: new HookMap(() => new SyncBailHook(["pattern"])),
canRename: new HookMap(() => new SyncBailHook(["initExpression"])),
rename: new HookMap(() => new SyncBailHook(["initExpression"])),
assigned: new HookMap(() => new SyncBailHook(["expression"])),
assign: new HookMap(() => new SyncBailHook(["expression"])),
typeof: new HookMap(() => new SyncBailHook(["expression"])),
importCall: new SyncBailHook(["expression"]),
topLevelAwait: new SyncBailHook(["expression"]),
call: new HookMap(() => new SyncBailHook(["expression"])),
callMemberChain: new HookMap(
() => new SyncBailHook(["expression", "rootRaw", "members"])
),
new: new HookMap(() => new SyncBailHook(["expression"])),
expression: new HookMap(() => new SyncBailHook(["expression"])),
expressionMemberChain: new HookMap(
() => new SyncBailHook(["expression", "rootRaw", "members"])
),
expressionConditionalOperator: new SyncBailHook(["expression"]),
expressionLogicalOperator: new SyncBailHook(["expression"]),
program: new SyncBailHook(["ast", "comments"])
});
this.options = options;
this.sourceType = sourceType;
this.scope = undefined;
this.state = undefined;
this.comments = undefined;
this.initializeEvaluating();
}
initializeEvaluating() {
this.hooks.evaluate.for("Literal").tap("JavascriptParser", expr => {
switch (typeof expr.value) {
case "number":
return new BasicEvaluatedExpression()
.setNumber(expr.value)
.setRange(expr.range);
case "string":
return new BasicEvaluatedExpression()
.setString(expr.value)
.setRange(expr.range);
case "boolean":
return new BasicEvaluatedExpression()
.setBoolean(expr.value)
.setRange(expr.range);
}
if (expr.value === null) {
return new BasicEvaluatedExpression().setNull().setRange(expr.range);
}
if (expr.value instanceof RegExp) {
return new BasicEvaluatedExpression()
.setRegExp(expr.value)
.setRange(expr.range);
}
});
this.hooks.evaluate
.for("LogicalExpression")
.tap("JavascriptParser", expr => {
let left;
let leftAsBool;
let right;
if (expr.operator === "&&") {
left = this.evaluateExpression(expr.left);
leftAsBool = left && left.asBool();
if (leftAsBool === false) return left.setRange(expr.range);
if (leftAsBool !== true) return;
right = this.evaluateExpression(expr.right);
return right.setRange(expr.range);
} else if (expr.operator === "||") {
left = this.evaluateExpression(expr.left);
leftAsBool = left && left.asBool();
if (leftAsBool === true) return left.setRange(expr.range);
if (leftAsBool !== false) return;
right = this.evaluateExpression(expr.right);
return right.setRange(expr.range);
}
});
this.hooks.evaluate
.for("BinaryExpression")
.tap("JavascriptParser", expr => {
let left;
let right;
let res;
if (expr.operator === "+") {
left = this.evaluateExpression(expr.left);
right = this.evaluateExpression(expr.right);
if (!left || !right) return;
res = new BasicEvaluatedExpression();
if (left.isString()) {
if (right.isString()) {
res.setString(left.string + right.string);
} else if (right.isNumber()) {
res.setString(left.string + right.number);
} else if (
right.isWrapped() &&
right.prefix &&
right.prefix.isString()
) {
// "left" + ("prefix" + inner + "postfix")
// => ("leftprefix" + inner + "postfix")
res.setWrapped(
new BasicEvaluatedExpression()
.setString(left.string + right.prefix.string)
.setRange(joinRanges(left.range, right.prefix.range)),
right.postfix,
right.wrappedInnerExpressions
);
} else if (right.isWrapped()) {
// "left" + ([null] + inner + "postfix")
// => ("left" + inner + "postfix")
res.setWrapped(
left,
right.postfix,
right.wrappedInnerExpressions
);
} else {
// "left" + expr
// => ("left" + expr + "")
res.setWrapped(left, null, [right]);
}
} else if (left.isNumber()) {
if (right.isString()) {
res.setString(left.number + right.string);
} else if (right.isNumber()) {
res.setNumber(left.number + right.number);
} else {
return;
}
} else if (left.isWrapped()) {
if (left.postfix && left.postfix.isString() && right.isString()) {
// ("prefix" + inner + "postfix") + "right"
// => ("prefix" + inner + "postfixright")
res.setWrapped(
left.prefix,
new BasicEvaluatedExpression()
.setString(left.postfix.string + right.string)
.setRange(joinRanges(left.postfix.range, right.range)),
left.wrappedInnerExpressions
);
} else if (
left.postfix &&
left.postfix.isString() &&
right.isNumber()
) {
// ("prefix" + inner + "postfix") + 123
// => ("prefix" + inner + "postfix123")
res.setWrapped(
left.prefix,
new BasicEvaluatedExpression()
.setString(left.postfix.string + right.number)
.setRange(joinRanges(left.postfix.range, right.range)),
left.wrappedInnerExpressions
);
} else if (right.isString()) {
// ("prefix" + inner + [null]) + "right"
// => ("prefix" + inner + "right")
res.setWrapped(left.prefix, right, left.wrappedInnerExpressions);
} else if (right.isNumber()) {
// ("prefix" + inner + [null]) + 123
// => ("prefix" + inner + "123")
res.setWrapped(
left.prefix,
new BasicEvaluatedExpression()
.setString(right.number + "")
.setRange(right.range),
left.wrappedInnerExpressions
);
} else if (right.isWrapped()) {
// ("prefix1" + inner1 + "postfix1") + ("prefix2" + inner2 + "postfix2")
// ("prefix1" + inner1 + "postfix1" + "prefix2" + inner2 + "postfix2")
res.setWrapped(
left.prefix,
right.postfix,
left.wrappedInnerExpressions &&
right.wrappedInnerExpressions &&
left.wrappedInnerExpressions
.concat(left.postfix ? [left.postfix] : [])
.concat(right.prefix ? [right.prefix] : [])
.concat(right.wrappedInnerExpressions)
);
} else {
// ("prefix" + inner + postfix) + expr
// => ("prefix" + inner + postfix + expr + [null])
res.setWrapped(
left.prefix,
null,
left.wrappedInnerExpressions &&
left.wrappedInnerExpressions.concat(
left.postfix ? [left.postfix, right] : [right]
)
);
}
} else {
if (right.isString()) {
// left + "right"
// => ([null] + left + "right")
res.setWrapped(null, right, [left]);
} else if (right.isWrapped()) {
// left + (prefix + inner + "postfix")
// => ([null] + left + prefix + inner + "postfix")
res.setWrapped(
null,
right.postfix,
right.wrappedInnerExpressions &&
(right.prefix ? [left, right.prefix] : [left]).concat(
right.wrappedInnerExpressions
)
);
} else {
return;
}
}
res.setRange(expr.range);
return res;
} else if (expr.operator === "-") {
left = this.evaluateExpression(expr.left);
right = this.evaluateExpression(expr.right);
if (!left || !right) return;
if (!left.isNumber() || !right.isNumber()) return;
res = new BasicEvaluatedExpression();
res.setNumber(left.number - right.number);
res.setRange(expr.range);
return res;
} else if (expr.operator === "*") {
left = this.evaluateExpression(expr.left);
right = this.evaluateExpression(expr.right);
if (!left || !right) return;
if (!left.isNumber() || !right.isNumber()) return;
res = new BasicEvaluatedExpression();
res.setNumber(left.number * right.number);
res.setRange(expr.range);
return res;
} else if (expr.operator === "/") {
left = this.evaluateExpression(expr.left);
right = this.evaluateExpression(expr.right);
if (!left || !right) return;
if (!left.isNumber() || !right.isNumber()) return;
res = new BasicEvaluatedExpression();
res.setNumber(left.number / right.number);
res.setRange(expr.range);
return res;
} else if (expr.operator === "**") {
left = this.evaluateExpression(expr.left);
right = this.evaluateExpression(expr.right);
if (!left || !right) return;
if (!left.isNumber() || !right.isNumber()) return;
res = new BasicEvaluatedExpression();
res.setNumber(Math.pow(left.number, right.number));
res.setRange(expr.range);
return res;
} else if (expr.operator === "==" || expr.operator === "===") {
left = this.evaluateExpression(expr.left);
right = this.evaluateExpression(expr.right);
if (!left || !right) return;
res = new BasicEvaluatedExpression();
res.setRange(expr.range);
if (left.isString() && right.isString()) {
return res.setBoolean(left.string === right.string);
} else if (left.isNumber() && right.isNumber()) {
return res.setBoolean(left.number === right.number);
} else if (left.isBoolean() && right.isBoolean()) {
return res.setBoolean(left.bool === right.bool);
}
} else if (expr.operator === "!=" || expr.operator === "!==") {
left = this.evaluateExpression(expr.left);
right = this.evaluateExpression(expr.right);
if (!left || !right) return;
res = new BasicEvaluatedExpression();
res.setRange(expr.range);
if (left.isString() && right.isString()) {
return res.setBoolean(left.string !== right.string);
} else if (left.isNumber() && right.isNumber()) {
return res.setBoolean(left.number !== right.number);
} else if (left.isBoolean() && right.isBoolean()) {
return res.setBoolean(left.bool !== right.bool);
}
} else if (expr.operator === "&") {
left = this.evaluateExpression(expr.left);
right = this.evaluateExpression(expr.right);
if (!left || !right) return;
if (!left.isNumber() || !right.isNumber()) return;
res = new BasicEvaluatedExpression();
res.setNumber(left.number & right.number);
res.setRange(expr.range);
return res;
} else if (expr.operator === "|") {
left = this.evaluateExpression(expr.left);
right = this.evaluateExpression(expr.right);
if (!left || !right) return;
if (!left.isNumber() || !right.isNumber()) return;
res = new BasicEvaluatedExpression();
res.setNumber(left.number | right.number);
res.setRange(expr.range);
return res;
} else if (expr.operator === "^") {
left = this.evaluateExpression(expr.left);
right = this.evaluateExpression(expr.right);
if (!left || !right) return;
if (!left.isNumber() || !right.isNumber()) return;
res = new BasicEvaluatedExpression();
res.setNumber(left.number ^ right.number);
res.setRange(expr.range);
return res;
} else if (expr.operator === ">>>") {
left = this.evaluateExpression(expr.left);
right = this.evaluateExpression(expr.right);
if (!left || !right) return;
if (!left.isNumber() || !right.isNumber()) return;
res = new BasicEvaluatedExpression();
res.setNumber(left.number >>> right.number);
res.setRange(expr.range);
return res;
} else if (expr.operator === ">>") {
left = this.evaluateExpression(expr.left);
right = this.evaluateExpression(expr.right);
if (!left || !right) return;
if (!left.isNumber() || !right.isNumber()) return;
res = new BasicEvaluatedExpression();
res.setNumber(left.number >> right.number);
res.setRange(expr.range);
return res;
} else if (expr.operator === "<<") {
left = this.evaluateExpression(expr.left);
right = this.evaluateExpression(expr.right);
if (!left || !right) return;
if (!left.isNumber() || !right.isNumber()) return;
res = new BasicEvaluatedExpression();
res.setNumber(left.number << right.number);
res.setRange(expr.range);
return res;
}
});
this.hooks.evaluate.for("UnaryExpression").tap("JavascriptParser", expr => {
if (expr.operator === "typeof") {
let res;
let name;
if (expr.argument.type === "Identifier") {
name =
this.scope.renames.get(expr.argument.name) || expr.argument.name;
if (!this.scope.definitions.has(name)) {
const hook = this.hooks.evaluateTypeof.get(name);
if (hook !== undefined) {
res = hook.call(expr);
if (res !== undefined) return res;
}
}
}
if (expr.argument.type === "MemberExpression") {
const exprName = this.getNameForExpression(expr.argument);
if (exprName && exprName.free) {
const hook = this.hooks.evaluateTypeof.get(exprName.name);
if (hook !== undefined) {
res = hook.call(expr);
if (res !== undefined) return res;
}
}
}
if (expr.argument.type === "FunctionExpression") {
return new BasicEvaluatedExpression()
.setString("function")
.setRange(expr.range);
}
const arg = this.evaluateExpression(expr.argument);
if (arg.isString() || arg.isWrapped()) {
return new BasicEvaluatedExpression()
.setString("string")
.setRange(expr.range);
}
if (arg.isNumber()) {
return new BasicEvaluatedExpression()
.setString("number")
.setRange(expr.range);
}
if (arg.isBoolean()) {
return new BasicEvaluatedExpression()
.setString("boolean")
.setRange(expr.range);
}
if (arg.isArray() || arg.isConstArray() || arg.isRegExp()) {
return new BasicEvaluatedExpression()
.setString("object")
.setRange(expr.range);
}
} else if (expr.operator === "!") {
const argument = this.evaluateExpression(expr.argument);
if (!argument) return;
if (argument.isBoolean()) {
return new BasicEvaluatedExpression()
.setBoolean(!argument.bool)
.setRange(expr.range);
}
if (argument.isTruthy()) {
return new BasicEvaluatedExpression()
.setBoolean(false)
.setRange(expr.range);
}
if (argument.isFalsy()) {
return new BasicEvaluatedExpression()
.setBoolean(true)
.setRange(expr.range);
}
if (argument.isString()) {
return new BasicEvaluatedExpression()
.setBoolean(!argument.string)
.setRange(expr.range);
}
if (argument.isNumber()) {
return new BasicEvaluatedExpression()
.setBoolean(!argument.number)
.setRange(expr.range);
}
} else if (expr.operator === "~") {
const argument = this.evaluateExpression(expr.argument);
if (!argument) return;
if (!argument.isNumber()) return;
const res = new BasicEvaluatedExpression();
res.setNumber(~argument.number);
res.setRange(expr.range);
return res;
} else if (expr.operator === "+") {
const argument = this.evaluateExpression(expr.argument);
if (!argument) return;
if (argument.isNumber()) {
const res = new BasicEvaluatedExpression();
res.setNumber(+argument.number);
res.setRange(expr.range);
return res;
} else if (argument.isString()) {
const res = new BasicEvaluatedExpression();
res.setNumber(+argument.string);
res.setRange(expr.range);
return res;
}
}
});
this.hooks.evaluateTypeof.for("undefined").tap("JavascriptParser", expr => {
return new BasicEvaluatedExpression()
.setString("undefined")
.setRange(expr.range);
});
this.hooks.evaluate.for("Identifier").tap("JavascriptParser", expr => {
const name = this.scope.renames.get(expr.name) || expr.name;
if (!this.scope.definitions.has(expr.name)) {
const hook = this.hooks.evaluateIdentifier.get(name);
if (hook !== undefined) {
const result = hook.call(expr);
if (result) return result;
}
return new BasicEvaluatedExpression()
.setIdentifier(name)
.setRange(expr.range);
} else {
const hook = this.hooks.evaluateDefinedIdentifier.get(name);
if (hook !== undefined) {
return hook.call(expr);
}
}
});
this.hooks.evaluate.for("ThisExpression").tap("JavascriptParser", expr => {
const name = this.scope.renames.get("this");
if (name) {
const hook = this.hooks.evaluateIdentifier.get(name);
if (hook !== undefined) {
const result = hook.call(expr);
if (result) return result;
}
return new BasicEvaluatedExpression()
.setIdentifier(name)
.setRange(expr.range);
}
});
this.hooks.evaluate
.for("MemberExpression")
.tap("JavascriptParser", expression => {
let exprName = this.getNameForExpression(expression);
if (exprName) {
if (exprName.free) {
const hook = this.hooks.evaluateIdentifier.get(exprName.name);
if (hook !== undefined) {
const result = hook.call(expression);
if (result) return result;
}
return new BasicEvaluatedExpression()
.setIdentifier(exprName.name)
.setRange(expression.range);
} else {
const hook = this.hooks.evaluateDefinedIdentifier.get(
exprName.name
);
if (hook !== undefined) {
return hook.call(expression);
}
}
}
});
this.hooks.evaluate.for("CallExpression").tap("JavascriptParser", expr => {
if (expr.callee.type !== "MemberExpression") return;
if (
expr.callee.property.type !==
(expr.callee.computed ? "Literal" : "Identifier")
)
return;
const param = this.evaluateExpression(expr.callee.object);
if (!param) return;
const property = expr.callee.property.name || expr.callee.property.value;
const hook = this.hooks.evaluateCallExpressionMember.get(property);
if (hook !== undefined) {
return hook.call(expr, param);
}
});
this.hooks.evaluateCallExpressionMember
.for("replace")
.tap("JavascriptParser", (expr, param) => {
if (!param.isString()) return;
if (expr.arguments.length !== 2) return;
let arg1 = this.evaluateExpression(expr.arguments[0]);
let arg2 = this.evaluateExpression(expr.arguments[1]);
if (!arg1.isString() && !arg1.isRegExp()) return;
arg1 = arg1.regExp || arg1.string;
if (!arg2.isString()) return;
arg2 = arg2.string;
return new BasicEvaluatedExpression()
.setString(param.string.replace(arg1, arg2))
.setRange(expr.range);
});
["substr", "substring"].forEach(fn => {
this.hooks.evaluateCallExpressionMember
.for(fn)
.tap("JavascriptParser", (expr, param) => {
if (!param.isString()) return;
let arg1;
let result,
str = param.string;
switch (expr.arguments.length) {
case 1:
arg1 = this.evaluateExpression(expr.arguments[0]);
if (!arg1.isNumber()) return;
result = str[fn](arg1.number);
break;
case 2: {
arg1 = this.evaluateExpression(expr.arguments[0]);
const arg2 = this.evaluateExpression(expr.arguments[1]);
if (!arg1.isNumber()) return;
if (!arg2.isNumber()) return;
result = str[fn](arg1.number, arg2.number);
break;
}
default:
return;
}
return new BasicEvaluatedExpression()
.setString(result)
.setRange(expr.range);
});
});
/**
* @param {string} kind "cooked" | "raw"
* @param {TODO} templateLiteralExpr TemplateLiteral expr
* @returns {{quasis: BasicEvaluatedExpression[], parts: BasicEvaluatedExpression[]}} Simplified template
*/
const getSimplifiedTemplateResult = (kind, templateLiteralExpr) => {
const quasis = [];
const parts = [];
for (let i = 0; i < templateLiteralExpr.quasis.length; i++) {
const quasiExpr = templateLiteralExpr.quasis[i];
const quasi = quasiExpr.value[kind];
if (i > 0) {
const prevExpr = parts[parts.length - 1];
const expr = this.evaluateExpression(
templateLiteralExpr.expressions[i - 1]
);
const exprAsString = expr.asString();
if (typeof exprAsString === "string") {
// We can merge quasi + expr + quasi when expr
// is a const string
prevExpr.setString(prevExpr.string + exprAsString + quasi);
prevExpr.setRange([prevExpr.range[0], quasiExpr.range[1]]);
// We unset the expression as it doesn't match to a single expression
prevExpr.setExpression(undefined);
continue;
}
parts.push(expr);
}
const part = new BasicEvaluatedExpression()
.setString(quasi)
.setRange(quasiExpr.range)
.setExpression(quasiExpr);
quasis.push(part);
parts.push(part);
}
return {
quasis,
parts
};
};
this.hooks.evaluate.for("TemplateLiteral").tap("JavascriptParser", node => {
const { quasis, parts } = getSimplifiedTemplateResult("cooked", node);
if (parts.length === 1) {
return parts[0].setRange(node.range);
}
return new BasicEvaluatedExpression()
.setTemplateString(quasis, parts, "cooked")
.setRange(node.range);
});
this.hooks.evaluate
.for("TaggedTemplateExpression")
.tap("JavascriptParser", node => {
if (this.evaluateExpression(node.tag).identifier !== "String.raw")
return;
const { quasis, parts } = getSimplifiedTemplateResult(
"raw",
node.quasi
);
if (parts.length === 1) {
return parts[0].setRange(node.range);
}
return new BasicEvaluatedExpression()
.setTemplateString(quasis, parts, "raw")
.setRange(node.range);
});
this.hooks.evaluateCallExpressionMember
.for("concat")
.tap("JavascriptParser", (expr, param) => {
if (!param.isString() && !param.isWrapped()) return;
let stringSuffix = null;
let hasUnknownParams = false;
for (let i = expr.arguments.length - 1; i >= 0; i--) {
const argExpr = this.evaluateExpression(expr.arguments[i]);
if (!argExpr.isString() && !argExpr.isNumber()) {
hasUnknownParams = true;
break;
}
const value = argExpr.isString()
? argExpr.string
: "" + argExpr.number;
const newString = value + (stringSuffix ? stringSuffix.string : "");
const newRange = [
argExpr.range[0],
(stringSuffix || argExpr).range[1]
];
stringSuffix = new BasicEvaluatedExpression()
.setString(newString)
.setRange(newRange);
}
if (hasUnknownParams) {
const prefix = param.isString() ? param : param.prefix;
return new BasicEvaluatedExpression()
.setWrapped(prefix, stringSuffix)
.setRange(expr.range);
} else if (param.isWrapped()) {
const postfix = stringSuffix || param.postfix;
return new BasicEvaluatedExpression()
.setWrapped(param.prefix, postfix)
.setRange(expr.range);
} else {
const newString =
param.string + (stringSuffix ? stringSuffix.string : "");
return new BasicEvaluatedExpression()
.setString(newString)
.setRange(expr.range);
}
});
this.hooks.evaluateCallExpressionMember
.for("split")
.tap("JavascriptParser", (expr, param) => {
if (!param.isString()) return;
if (expr.arguments.length !== 1) return;
let result;
const arg = this.evaluateExpression(expr.arguments[0]);
if (arg.isString()) {
result = param.string.split(arg.string);
} else if (arg.isRegExp()) {
result = param.string.split(arg.regExp);
} else {
return;
}
return new BasicEvaluatedExpression()
.setArray(result)
.setRange(expr.range);
});
this.hooks.evaluate
.for("ConditionalExpression")
.tap("JavascriptParser", expr => {
const condition = this.evaluateExpression(expr.test);
const conditionValue = condition.asBool();
let res;
if (conditionValue === undefined) {
const consequent = this.evaluateExpression(expr.consequent);
const alternate = this.evaluateExpression(expr.alternate);
if (!consequent || !alternate) return;
res = new BasicEvaluatedExpression();
if (consequent.isConditional()) {
res.setOptions(consequent.options);
} else {
res.setOptions([consequent]);
}
if (alternate.isConditional()) {
res.addOptions(alternate.options);
} else {
res.addOptions([alternate]);
}
} else {
res = this.evaluateExpression(
conditionValue ? expr.consequent : expr.alternate
);
}
res.setRange(expr.range);
return res;
});
this.hooks.evaluate.for("ArrayExpression").tap("JavascriptParser", expr => {
const items = expr.elements.map(element => {
return element !== null && this.evaluateExpression(element);
});
if (!items.every(Boolean)) return;
return new BasicEvaluatedExpression()
.setItems(items)
.setRange(expr.range);
});
}
getRenameIdentifier(expr) {
const result = this.evaluateExpression(expr);
if (result && result.isIdentifier()) {
return result.identifier;
}
}
walkClass(classy) {
if (classy.superClass) this.walkExpression(classy.superClass);
if (classy.body && classy.body.type === "ClassBody") {
const wasTopLevel = this.scope.topLevelScope;
this.scope.topLevelScope = false;
for (const methodDefinition of classy.body.body) {
if (methodDefinition.type === "MethodDefinition") {
this.walkMethodDefinition(methodDefinition);
}
}
this.scope.topLevelScope = wasTopLevel;
}
}
walkMethodDefinition(methodDefinition) {
if (methodDefinition.computed && methodDefinition.key) {
this.walkExpression(methodDefinition.key);
}
if (methodDefinition.value) {
this.walkExpression(methodDefinition.value);
}
}
// Prewalking iterates the scope for variable declarations
prewalkStatements(statements) {
for (let index = 0, len = statements.length; index < len; index++) {
const statement = statements[index];
this.prewalkStatement(statement);
}
}
// Block-Prewalking iterates the scope for block variable declarations
blockPrewalkStatements(statements) {
for (let index = 0, len = statements.length; index < len; index++) {
const statement = statements[index];
this.blockPrewalkStatement(statement);
}
}
// Walking iterates the statements and expressions and processes them
walkStatements(statements) {
for (let index = 0, len = statements.length; index < len; index++) {
const statement = statements[index];
this.walkStatement(statement);
}
}
prewalkStatement(statement) {
switch (statement.type) {
case "BlockStatement":
this.prewalkBlockStatement(statement);
break;
case "DoWhileStatement":
this.prewalkDoWhileStatement(statement);
break;
case "ExportAllDeclaration":
this.prewalkExportAllDeclaration(statement);
break;
case "ExportDefaultDeclaration":
this.prewalkExportDefaultDeclaration(statement);
break;
case "ExportNamedDeclaration":
this.prewalkExportNamedDeclaration(statement);
break;
case "ForInStatement":
this.prewalkForInStatement(statement);
break;
case "ForOfStatement":
this.prewalkForOfStatement(statement);
break;
case "ForStatement":
this.prewalkForStatement(statement);
break;
case "FunctionDeclaration":
this.prewalkFunctionDeclaration(statement);
break;
case "IfStatement":
this.prewalkIfStatement(statement);
break;
case "ImportDeclaration":
this.prewalkImportDeclaration(statement);
break;
case "LabeledStatement":
this.prewalkLabeledStatement(statement);
break;
case "SwitchStatement":
this.prewalkSwitchStatement(statement);
break;
case "TryStatement":
this.prewalkTryStatement(statement);
break;
case "VariableDeclaration":
this.prewalkVariableDeclaration(statement);
break;
case "WhileStatement":
this.prewalkWhileStatement(statement);
break;
case "WithStatement":
this.prewalkWithStatement(statement);
break;
}
}
blockPrewalkStatement(statement) {
switch (statement.type) {
case "VariableDeclaration":
this.blockPrewalkVariableDeclaration(statement);
break;
case "ExportDefaultDeclaration":
this.blockPrewalkExportDefaultDeclaration(statement);
break;
case "ExportNamedDeclaration":
this.blockPrewalkExportNamedDeclaration(statement);
break;
case "ClassDeclaration":
this.blockPrewalkClassDeclaration(statement);
break;
}
}
walkStatement(statement) {
if (this.hooks.statement.call(statement) !== undefined) return;
switch (statement.type) {
case "BlockStatement":
this.walkBlockStatement(statement);
break;
case "ClassDeclaration":
this.walkClassDeclaration(statement);
break;
case "DoWhileStatement":
this.walkDoWhileStatement(statement);
break;
case "ExportDefaultDeclaration":
this.walkExportDefaultDeclaration(statement);
break;
case "ExportNamedDeclaration":
this.walkExportNamedDeclaration(statement);
break;
case "ExpressionStatement":
this.walkExpressionStatement(statement);
break;
case "ForInStatement":
this.walkForInStatement(statement);
break;
case "ForOfStatement":
this.walkForOfStatement(statement);
break;
case "ForStatement":
this.walkForStatement(statement);
break;
case "FunctionDeclaration":
this.walkFunctionDeclaration(statement);
break;
case "IfStatement":
this.walkIfStatement(statement);
break;
case "LabeledStatement":
this.walkLabeledStatement(statement);
break;
case "ReturnStatement":
this.walkReturnStatement(statement);
break;
case "SwitchStatement":
this.walkSwitchStatement(statement);
break;
case "ThrowStatement":
this.walkThrowStatement(statement);
break;
case "TryStatement":
this.walkTryStatement(statement);
break;
case "VariableDeclaration":
this.walkVariableDeclaration(statement);
break;
case "WhileStatement":
this.walkWhileStatement(statement);
break;
case "WithStatement":
this.walkWithStatement(statement);
break;
}
}
// Real Statements
prewalkBlockStatement(statement) {
this.prewalkStatements(statement.body);
}
walkBlockStatement(statement) {
this.inBlockScope(() => {
const body = statement.body;
this.blockPrewalkStatements(body);
this.walkStatements(body);
});
}
walkExpressionStatement(statement) {
this.walkExpression(statement.expression);
}
prewalkIfStatement(statement) {
this.prewalkStatement(statement.consequent);
if (statement.alternate) {
this.prewalkStatement(statement.alternate);
}
}
walkIfStatement(statement) {
const result = this.hooks.statementIf.call(statement);
if (result === undefined) {
this.walkExpression(statement.test);
this.walkStatement(statement.consequent);
if (statement.alternate) {
this.walkStatement(statement.alternate);
}
} else {
if (result) {
this.walkStatement(statement.consequent);
} else if (statement.alternate) {
this.walkStatement(statement.alternate);
}
}
}
prewalkLabeledStatement(statement) {
this.prewalkStatement(statement.body);
}
walkLabeledStatement(statement) {
const hook = this.hooks.label.get(statement.label.name);
if (hook !== undefined) {
const result = hook.call(statement);
if (result === true) return;
}
this.walkStatement(statement.body);
}
prewalkWithStatement(statement) {
this.prewalkStatement(statement.body);
}
walkWithStatement(statement) {
this.walkExpression(statement.object);
this.walkStatement(statement.body);
}
prewalkSwitchStatement(statement) {
this.prewalkSwitchCases(statement.cases);
}
walkSwitchStatement(statement) {
this.walkExpression(statement.discriminant);
this.walkSwitchCases(statement.cases);
}
walkTerminatingStatement(statement) {
if (statement.argument) this.walkExpression(statement.argument);
}
walkReturnStatement(statement) {
this.walkTerminatingStatement(statement);
}
walkThrowStatement(statement) {
this.walkTerminatingStatement(statement);
}
prewalkTryStatement(statement) {
this.prewalkStatement(statement.block);
}
walkTryStatement(statement) {
if (this.scope.inTry) {
this.walkStatement(statement.block);
} else {
this.scope.inTry = true;
this.walkStatement(statement.block);
this.scope.inTry = false;
}
if (statement.handler) this.walkCatchClause(statement.handler);
if (statement.finalizer) this.walkStatement(statement.finalizer);
}
prewalkWhileStatement(statement) {
this.prewalkStatement(statement.body);
}
walkWhileStatement(statement) {
this.walkExpression(statement.test);
this.walkStatement(statement.body);
}
prewalkDoWhileStatement(statement) {
this.prewalkStatement(statement.body);
}
walkDoWhileStatement(statement) {
this.walkStatement(statement.body);
this.walkExpression(statement.test);
}
prewalkForStatement(statement) {
if (statement.init) {
if (statement.init.type === "VariableDeclaration") {
this.prewalkStatement(statement.init);
}
}
this.prewalkStatement(statement.body);
}
walkForStatement(statement) {
this.inBlockScope(() => {
if (statement.init) {
if (statement.init.type === "VariableDeclaration") {
this.blockPrewalkVariableDeclaration(statement.init);
this.walkStatement(statement.init);
} else {
this.walkExpression(statement.init);
}
}
if (statement.test) {
this.walkExpression(statement.test);
}
if (statement.update) {
this.walkExpression(statement.update);
}
const body = statement.body;
if (body.type === "BlockStatement") {
// no need to add additional scope
this.blockPrewalkStatements(body.body);
this.walkStatements(body.body);
} else {
this.walkStatement(body);
}
});
}
prewalkForInStatement(statement) {
if (statement.left.type === "VariableDeclaration") {
this.prewalkVariableDeclaration(statement.left);
}
this.prewalkStatement(statement.body);
}
walkForInStatement(statement) {
this.inBlockScope(() => {
if (statement.left.type === "VariableDeclaration") {
this.blockPrewalkVariableDeclaration(statement.left);
this.walkVariableDeclaration(statement.left);
} else {
this.walkPattern(statement.left);
}
this.walkExpression(statement.right);
const body = statement.body;
if (body.type === "BlockStatement") {
// no need to add additional scope
this.blockPrewalkStatements(body.body);
this.walkStatements(body.body);
} else {
this.walkStatement(body);
}
});
}
prewalkForOfStatement(statement) {
if (statement.await && this.scope.topLevelScope === true) {
this.hooks.topLevelAwait.call(statement);
}
if (statement.left.type === "VariableDeclaration") {
this.prewalkVariableDeclaration(statement.left);
}
this.prewalkStatement(statement.body);
}
walkForOfStatement(statement) {
this.inBlockScope(() => {
if (statement.left.type === "VariableDeclaration") {
this.blockPrewalkVariableDeclaration(statement.left);
this.walkVariableDeclaration(statement.left);
} else {
this.walkPattern(statement.left);
}
this.walkExpression(statement.right);
const body = statement.body;
if (body.type === "BlockStatement") {
// no need to add additional scope
this.blockPrewalkStatements(body.body);
this.walkStatements(body.body);
} else {
this.walkStatement(body);
}
});
}
// Declarations
prewalkFunctionDeclaration(statement) {
if (statement.id) {
this.scope.renames.set(statement.id.name, null);
this.scope.definitions.add(statement.id.name);
}
}
walkFunctionDeclaration(statement) {
const wasTopLevel = this.scope.topLevelScope;
this.scope.topLevelScope = false;
this.inFunctionScope(true, statement.params, () => {
for (const param of statement.params) {
this.walkPattern(param);
}
if (statement.body.type === "BlockStatement") {
this.detectStrictMode(statement.body.body);
this.prewalkStatement(statement.body);
this.walkStatement(statement.body);
} else {
this.walkExpression(statement.body);
}
});
this.scope.topLevelScope = wasTopLevel;
}
prewalkImportDeclaration(statement) {
const source = statement.source.value;
this.hooks.import.call(statement, source);
for (const specifier of statement.specifiers) {
const name = specifier.local.name;
this.scope.renames.set(name, null);
this.scope.definitions.add(name);
switch (specifier.type) {
case "ImportDefaultSpecifier":
this.hooks.importSpecifier.call(statement, source, "default", name);
break;
case "ImportSpecifier":
this.hooks.importSpecifier.call(
statement,
source,
specifier.imported.name,
name
);
break;
case "ImportNamespaceSpecifier":
this.hooks.importSpecifier.call(statement, source, null, name);
break;
}
}
}
enterDeclaration(declaration, onIdent) {
switch (declaration.type) {
case "VariableDeclaration":
for (const declarator of declaration.declarations) {
switch (declarator.type) {
case "VariableDeclarator": {
this.enterPattern(declarator.id, onIdent);
break;
}
}
}
break;
case "FunctionDeclaration":
this.enterPattern(declaration.id, onIdent);
break;
case "ClassDeclaration":
this.enterPattern(declaration.id, onIdent);
break;
}
}
blockPrewalkExportNamedDeclaration(statement) {
if (statement.declaration) {
this.blockPrewalkStatement(statement.declaration);
}
}
prewalkExportNamedDeclaration(statement) {
let source;
if (statement.source) {
source = statement.source.value;
this.hooks.exportImport.call(statement, source);
} else {
this.hooks.export.call(statement);
}
if (statement.declaration) {
if (
!this.hooks.exportDeclaration.call(statement, statement.declaration)
) {
this.prewalkStatement(statement.declaration);
let index = 0;
this.enterDeclaration(statement.declaration, def => {
this.hooks.exportSpecifier.call(statement, def, def, index++);
});
}
}
if (statement.specifiers) {
for (
let specifierIndex = 0;
specifierIndex < statement.specifiers.length;
specifierIndex++
) {
const specifier = statement.specifiers[specifierIndex];
switch (specifier.type) {
case "ExportSpecifier": {
const name = specifier.exported.name;
if (source) {
this.hooks.exportImportSpecifier.call(
statement,
source,
specifier.local.name,
name,
specifierIndex
);
} else {
this.hooks.exportSpecifier.call(
statement,
specifier.local.name,
name,
specifierIndex
);
}
break;
}
}
}
}
}
walkExportNamedDeclaration(statement) {
if (statement.declaration) {
this.walkStatement(statement.declaration);
}
}
blockPrewalkExportDefaultDeclaration(statement) {
if (statement.declaration.type === "ClassDeclaration") {
this.blockPrewalkClassDeclaration(statement.declaration);
}
}
prewalkExportDefaultDeclaration(statement) {
this.prewalkStatement(statement.declaration);
if (
statement.declaration.id &&
statement.declaration.type !== "FunctionExpression" &&
statement.declaration.type !== "ClassExpression"
) {
this.hooks.exportSpecifier.call(
statement,
statement.declaration.id.name,
"default"
);
}
}
walkExportDefaultDeclaration(statement) {
this.hooks.export.call(statement);
if (
statement.declaration.id &&
statement.declaration.type !== "FunctionExpression" &&
statement.declaration.type !== "ClassExpression"
) {
if (
!this.hooks.exportDeclaration.call(statement, statement.declaration)
) {
this.walkStatement(statement.declaration);
}
} else {
// Acorn parses `export default function() {}` as `FunctionDeclaration` and
// `export default class {}` as `ClassDeclaration`, both with `id = null`.
// These nodes must be treated as expressions.
if (statement.declaration.type === "FunctionDeclaration") {
this.walkFunctionDeclaration(statement.declaration);
} else if (statement.declaration.type === "ClassDeclaration") {
this.walkClassDeclaration(statement.declaration);
} else {
this.walkExpression(statement.declaration);
}
if (!this.hooks.exportExpression.call(statement, statement.declaration)) {
this.hooks.exportSpecifier.call(
statement,
statement.declaration,
"default"
);
}
}
}
prewalkExportAllDeclaration(statement) {
const source = statement.source.value;
this.hooks.exportImport.call(statement, source);
this.hooks.exportImportSpecifier.call(statement, source, null, null, 0);
}
prewalkVariableDeclaration(statement) {
if (statement.kind !== "var") return;
this._prewalkVariableDeclaration(statement, this.hooks.varDeclarationVar);
}
blockPrewalkVariableDeclaration(statement) {
if (statement.kind === "var") return;
const hookMap =
statement.kind === "const"
? this.hooks.varDeclarationConst
: this.hooks.varDeclarationLet;
this._prewalkVariableDeclaration(statement, hookMap);
}
_prewalkVariableDeclaration(statement, hookMap) {
for (const declarator of statement.declarations) {
switch (declarator.type) {
case "VariableDeclarator": {
this.enterPattern(declarator.id, (name, decl) => {
let hook = hookMap.get(name);
if (hook === undefined || !hook.call(decl)) {
hook = this.hooks.varDeclaration.get(name);
if (hook === undefined || !hook.call(decl)) {
this.scope.renames.set(name, null);
this.scope.definitions.add(name);
}
}
});
break;
}
}
}
}
walkVariableDeclaration(statement) {
for (const declarator of statement.declarations) {
switch (declarator.type) {
case "VariableDeclarator": {
const renameIdentifier =
declarator.init && this.getRenameIdentifier(declarator.init);
if (renameIdentifier && declarator.id.type === "Identifier") {
const hook = this.hooks.canRename.get(renameIdentifier);
if (hook !== undefined && hook.call(declarator.init)) {
// renaming with "var a = b;"
const hook = this.hooks.rename.get(renameIdentifier);
if (hook === undefined || !hook.call(declarator.init)) {
this.scope.renames.set(
declarator.id.name,
this.scope.renames.get(renameIdentifier) || renameIdentifier
);
this.scope.definitions.delete(declarator.id.name);
}
break;
}
}
this.walkPattern(declarator.id);
if (declarator.init) this.walkExpression(declarator.init);
break;
}
}
}
}
blockPrewalkClassDeclaration(statement) {
if (statement.id) {
this.scope.renames.set(statement.id.name, null);
this.scope.definitions.add(statement.id.name);
}
}
walkClassDeclaration(statement) {
this.walkClass(statement);
}
prewalkSwitchCases(switchCases) {
for (let index = 0, len = switchCases.length; index < len; index++) {
const switchCase = switchCases[index];
this.prewalkStatements(switchCase.consequent);
}
}
walkSwitchCases(switchCases) {
for (let index = 0, len = switchCases.length; index < len; index++) {
const switchCase = switchCases[index];
if (switchCase.test) {
this.walkExpression(switchCase.test);
}
this.walkStatements(switchCase.consequent);
}
}
walkCatchClause(catchClause) {
this.inBlockScope(() => {
// Error binding is optional in catch clause since ECMAScript 2019
if (catchClause.param !== null) {
this.enterPattern(catchClause.param, ident => {
this.scope.renames.set(ident, null);
this.scope.definitions.add(ident);
});
this.walkPattern(catchClause.param);
}
this.prewalkStatement(catchClause.body);
this.walkStatement(catchClause.body);
});
}
walkPattern(pattern) {
switch (pattern.type) {
case "ArrayPattern":
this.walkArrayPattern(pattern);
break;
case "AssignmentPattern":
this.walkAssignmentPattern(pattern);
break;
case "MemberExpression":
this.walkMemberExpression(pattern);
break;
case "ObjectPattern":
this.walkObjectPattern(pattern);
break;
case "RestElement":
this.walkRestElement(pattern);
break;
}
}
walkAssignmentPattern(pattern) {
this.walkExpression(pattern.right);
this.walkPattern(pattern.left);
}
walkObjectPattern(pattern) {
for (let i = 0, len = pattern.properties.length; i < len; i++) {
const prop = pattern.properties[i];
if (prop) {
if (prop.computed) this.walkExpression(prop.key);
if (prop.value) this.walkPattern(prop.value);
}
}
}
walkArrayPattern(pattern) {
for (let i = 0, len = pattern.elements.length; i < len; i++) {
const element = pattern.elements[i];
if (element) this.walkPattern(element);
}
}
walkRestElement(pattern) {
this.walkPattern(pattern.argument);
}
walkExpressions(expressions) {
for (const expression of expressions) {
if (expression) {
this.walkExpression(expression);
}
}
}
walkExpression(expression) {
switch (expression.type) {
case "ArrayExpression":
this.walkArrayExpression(expression);
break;
case "ArrowFunctionExpression":
this.walkArrowFunctionExpression(expression);
break;
case "AssignmentExpression":
this.walkAssignmentExpression(expression);
break;
case "AwaitExpression":
this.walkAwaitExpression(expression);
break;
case "BinaryExpression":
this.walkBinaryExpression(expression);
break;
case "CallExpression":
this.walkCallExpression(expression);
break;
case "ClassExpression":
this.walkClassExpression(expression);
break;
case "ConditionalExpression":
this.walkConditionalExpression(expression);
break;
case "FunctionExpression":
this.walkFunctionExpression(expression);
break;
case "Identifier":
this.walkIdentifier(expression);
break;
case "LogicalExpression":
this.walkLogicalExpression(expression);
break;
case "MemberExpression":
this.walkMemberExpression(expression);
break;
case "NewExpression":
this.walkNewExpression(expression);
break;
case "ObjectExpression":
this.walkObjectExpression(expression);
break;
case "SequenceExpression":
this.walkSequenceExpression(expression);
break;
case "SpreadElement":
this.walkSpreadElement(expression);
break;
case "TaggedTemplateExpression":
this.walkTaggedTemplateExpression(expression);
break;
case "TemplateLiteral":
this.walkTemplateLiteral(expression);
break;
case "ThisExpression":
this.walkThisExpression(expression);
break;
case "UnaryExpression":
this.walkUnaryExpression(expression);
break;
case "UpdateExpression":
this.walkUpdateExpression(expression);
break;
case "YieldExpression":
this.walkYieldExpression(expression);
break;
}
}
walkAwaitExpression(expression) {
if (this.scope.topLevelScope === true)
this.hooks.topLevelAwait.call(expression);
this.walkExpression(expression.argument);
}
walkArrayExpression(expression) {
if (expression.elements) {
this.walkExpressions(expression.elements);
}
}
walkSpreadElement(expression) {
if (expression.argument) {
this.walkExpression(expression.argument);
}
}
walkObjectExpression(expression) {
for (
let propIndex = 0, len = expression.properties.length;
propIndex < len;
propIndex++
) {
const prop = expression.properties[propIndex];
if (prop.type === "SpreadElement") {
this.walkExpression(prop.argument);
continue;
}
if (prop.computed) {
this.walkExpression(prop.key);
}
if (prop.shorthand) {
this.scope.inShorthand = true;
}
this.walkExpression(prop.value);
if (prop.shorthand) {
this.scope.inShorthand = false;
}
}
}
walkFunctionExpression(expression) {
const wasTopLevel = this.scope.topLevelScope;
this.scope.topLevelScope = false;
const scopeParams = expression.params;
// Add function name in scope for recursive calls
if (expression.id) {
scopeParams.push(expression.id.name);
}
this.inFunctionScope(true, scopeParams, () => {
for (const param of expression.params) {
this.walkPattern(param);
}
if (expression.body.type === "BlockStatement") {
this.detectStrictMode(expression.body.body);
this.prewalkStatement(expression.body);
this.walkStatement(expression.body);
} else {
this.walkExpression(expression.body);
}
});
this.scope.topLevelScope = wasTopLevel;
}
walkArrowFunctionExpression(expression) {
const wasTopLevel = this.scope.topLevelScope;
this.scope.topLevelScope = wasTopLevel ? "arrow" : false;
this.inFunctionScope(false, expression.params, () => {
for (const param of expression.params) {
this.walkPattern(param);
}
if (expression.body.type === "BlockStatement") {
this.detectStrictMode(expression.body.body);
this.prewalkStatement(expression.body);
this.walkStatement(expression.body);
} else {
this.walkExpression(expression.body);
}
});
this.scope.topLevelScope = wasTopLevel;
}
walkSequenceExpression(expression) {
if (expression.expressions) this.walkExpressions(expression.expressions);
}
walkUpdateExpression(expression) {
this.walkExpression(expression.argument);
}
walkUnaryExpression(expression) {
if (expression.operator === "typeof") {
const exprName = this.getNameForExpression(expression.argument);
if (exprName && exprName.free) {
const hook = this.hooks.typeof.get(exprName.name);
if (hook !== undefined) {
const result = hook.call(expression);
if (result === true) return;
}
}
}
this.walkExpression(expression.argument);
}
walkLeftRightExpression(expression) {
this.walkExpression(expression.left);
this.walkExpression(expression.right);
}
walkBinaryExpression(expression) {
this.walkLeftRightExpression(expression);
}
walkLogicalExpression(expression) {
const result = this.hooks.expressionLogicalOperator.call(expression);
if (result === undefined) {
this.walkLeftRightExpression(expression);
} else {
if (result) {
this.walkExpression(expression.right);
}
}
}
walkAssignmentExpression(expression) {
const renameIdentifier = this.getRenameIdentifier(expression.right);
if (expression.left.type === "Identifier" && renameIdentifier) {
const hook = this.hooks.canRename.get(renameIdentifier);
if (hook !== undefined && hook.call(expression.right)) {
// renaming "a = b;"
const hook = this.hooks.rename.get(renameIdentifier);
if (hook === undefined || !hook.call(expression.right)) {
this.scope.renames.set(expression.left.name, renameIdentifier);
this.scope.definitions.delete(expression.left.name);
}
return;
}
}
if (expression.left.type === "Identifier") {
const assignedHook = this.hooks.assigned.get(expression.left.name);
if (assignedHook === undefined || !assignedHook.call(expression)) {
this.walkExpression(expression.right);
}
this.scope.renames.set(expression.left.name, null);
const assignHook = this.hooks.assign.get(expression.left.name);
if (assignHook === undefined || !assignHook.call(expression)) {
this.walkExpression(expression.left);
}
return;
}
this.walkExpression(expression.right);
this.walkPattern(expression.left);
this.enterPattern(expression.left, (name, decl) => {
this.scope.renames.set(name, null);
});
}
walkConditionalExpression(expression) {
const result = this.hooks.expressionConditionalOperator.call(expression);
if (result === undefined) {
this.walkExpression(expression.test);
this.walkExpression(expression.consequent);
if (expression.alternate) {
this.walkExpression(expression.alternate);
}
} else {
if (result) {
this.walkExpression(expression.consequent);
} else if (expression.alternate) {
this.walkExpression(expression.alternate);
}
}
}
walkNewExpression(expression) {
const callee = this.evaluateExpression(expression.callee);
if (callee.isIdentifier()) {
const hook = this.hooks.new.get(callee.identifier);
if (hook !== undefined) {
const result = hook.call(expression);
if (result === true) {
return;
}
}
}
this.walkExpression(expression.callee);
if (expression.arguments) {
this.walkExpressions(expression.arguments);
}
}
walkYieldExpression(expression) {
if (expression.argument) {
this.walkExpression(expression.argument);
}
}
walkTemplateLiteral(expression) {
if (expression.expressions) {
this.walkExpressions(expression.expressions);
}
}
walkTaggedTemplateExpression(expression) {
if (expression.tag) {
this.walkExpression(expression.tag);
}
if (expression.quasi && expression.quasi.expressions) {
this.walkExpressions(expression.quasi.expressions);
}
}
walkClassExpression(expression) {
this.walkClass(expression);
}
_walkIIFE(functionExpression, options, currentThis) {
const renameArgOrThis = argOrThis => {
const renameIdentifier = this.getRenameIdentifier(argOrThis);
if (renameIdentifier) {
const hook = this.hooks.canRename.get(renameIdentifier);
if (hook !== undefined && hook.call(argOrThis)) {
const hook = this.hooks.rename.get(renameIdentifier);
if (hook === undefined || !hook.call(argOrThis)) {
return renameIdentifier;
}
}
}
this.walkExpression(argOrThis);
};
const params = functionExpression.params;
const renameThis = currentThis ? renameArgOrThis(currentThis) : null;
const args = options.map(renameArgOrThis);
const wasTopLevel = this.scope.topLevelScope;
this.scope.topLevelScope = false;
const scopeParams = params.filter((identifier, idx) => !args[idx]);
// Add function name in scope for recursive calls
if (functionExpression.id) {
scopeParams.push(functionExpression.id.name);
}
this.inFunctionScope(true, scopeParams, () => {
if (renameThis) {
this.scope.renames.set("this", renameThis);
}
for (let i = 0; i < args.length; i++) {
const param = args[i];
if (!param) continue;
if (!params[i] || params[i].type !== "Identifier") continue;
this.scope.renames.set(params[i].name, param);
}
if (functionExpression.body.type === "BlockStatement") {
this.prewalkStatement(functionExpression.body);
this.walkStatement(functionExpression.body);
} else {
this.walkExpression(functionExpression.body);
}
});
this.scope.topLevelScope = wasTopLevel;
}
walkCallExpression(expression) {
if (
expression.callee.type === "MemberExpression" &&
expression.callee.object.type === "FunctionExpression" &&
!expression.callee.computed &&
(expression.callee.property.name === "call" ||
expression.callee.property.name === "bind") &&
expression.arguments.length > 0
) {
// (function(…) { }.call/bind(?, …))
this._walkIIFE(
expression.callee.object,
expression.arguments.slice(1),
expression.arguments[0]
);
} else if (expression.callee.type === "FunctionExpression") {
// (function(…) { }(…))
this._walkIIFE(expression.callee, expression.arguments, null);
} else if (expression.callee.type === "Import") {
let result = this.hooks.importCall.call(expression);
if (result === true) return;
if (expression.arguments) this.walkExpressions(expression.arguments);
} else {
const callee = this.evaluateExpression(expression.callee);
if (callee.isIdentifier()) {
const callHook = this.hooks.call.get(callee.identifier);
if (callHook !== undefined) {
let result = callHook.call(expression);
if (result === true) return;
}
}
const exprName = this.getNameForExpression(expression.callee);
if (exprName) {
const hook = this.hooks.callMemberChain.get(exprName.rootName);
if (hook !== undefined) {
const result = hook.call(
expression,
exprName.rootRaw,
exprName.members
);
if (result === true) return;
}
}
if (expression.callee) this.walkExpression(expression.callee);
if (expression.arguments) this.walkExpressions(expression.arguments);
}
}
walkMemberExpression(expression) {
const exprName = this.getNameForExpression(expression);
if (exprName && exprName.free) {
const expressionHook = this.hooks.expression.get(exprName.name);
if (expressionHook !== undefined) {
const result = expressionHook.call(expression);
if (result === true) return;
}
const expressionMemberChainHook = this.hooks.expressionMemberChain.get(
exprName.rootName
);
if (expressionMemberChainHook !== undefined) {
const result = expressionMemberChainHook.call(
expression,
exprName.rootRaw,
exprName.members
);
if (result === true) return;
}
// TODO optimize case where expression.object is a MemberExpression too.
// we can keep info here when calling walkMemberExpression directly
}
this.walkExpression(expression.object);
if (expression.computed === true) this.walkExpression(expression.property);
}
walkThisExpression(expression) {
const expressionHook = this.hooks.expression.get("this");
if (expressionHook !== undefined) {
expressionHook.call(expression);
}
}
walkIdentifier(expression) {
if (!this.scope.definitions.has(expression.name)) {
const hook = this.hooks.expression.get(
this.scope.renames.get(expression.name) || expression.name
);
if (hook !== undefined) {
const result = hook.call(expression);
if (result === true) return;
}
}
}
/**
* @deprecated
* @param {any} params scope params
* @param {function(): void} fn inner function
* @returns {void}
*/
inScope(params, fn) {
const oldScope = this.scope;
this.scope = {
topLevelScope: oldScope.topLevelScope,
inTry: false,
inShorthand: false,
isStrict: oldScope.isStrict,
definitions: oldScope.definitions.createChild(),
renames: oldScope.renames.createChild()
};
this.scope.renames.set("this", null);
this.enterPatterns(params, (ident, pattern) => {
const hook = pattern && this.hooks.pattern.get(ident);
if (!hook || hook.call(pattern) !== true) {
this.scope.renames.set(ident, null);
this.scope.definitions.add(ident);
}
});
fn();
this.scope = oldScope;
}
inFunctionScope(hasThis, params, fn) {
const oldScope = this.scope;
this.scope = {
topLevelScope: oldScope.topLevelScope,
inTry: false,
inShorthand: false,
isStrict: oldScope.isStrict,
definitions: oldScope.definitions.createChild(),
renames: oldScope.renames.createChild()
};
if (hasThis) {
this.scope.renames.set("this", null);
}
this.enterPatterns(params, (ident, pattern) => {
const hook = pattern && this.hooks.pattern.get(ident);
if (!hook || hook.call(pattern) !== true) {
this.scope.renames.set(ident, null);
this.scope.definitions.add(ident);
}
});
fn();
this.scope = oldScope;
}
inBlockScope(fn) {
const oldScope = this.scope;
this.scope = {
topLevelScope: oldScope.topLevelScope,
inTry: oldScope.inTry,
inShorthand: false,
isStrict: oldScope.isStrict,
definitions: oldScope.definitions.createChild(),
renames: oldScope.renames.createChild()
};
fn();
this.scope = oldScope;
}
detectStrictMode(statements) {
const isStrict =
statements.length >= 1 &&
statements[0].type === "ExpressionStatement" &&
statements[0].expression.type === "Literal" &&
statements[0].expression.value === "use strict";
if (isStrict) {
this.scope.isStrict = true;
}
}
enterPatterns(patterns, onIdent) {
for (const pattern of patterns) {
if (typeof pattern !== "string") {
this.enterPattern(pattern, onIdent);
} else if (pattern) {
onIdent(pattern);
}
}
}
enterPattern(pattern, onIdent) {
if (!pattern) return;
switch (pattern.type) {
case "ArrayPattern":
this.enterArrayPattern(pattern, onIdent);
break;
case "AssignmentPattern":
this.enterAssignmentPattern(pattern, onIdent);
break;
case "Identifier":
this.enterIdentifier(pattern, onIdent);
break;
case "ObjectPattern":
this.enterObjectPattern(pattern, onIdent);
break;
case "RestElement":
this.enterRestElement(pattern, onIdent);
break;
case "Property":
this.enterPattern(pattern.value, onIdent);
break;
}
}
enterIdentifier(pattern, onIdent) {
onIdent(pattern.name, pattern);
}
enterObjectPattern(pattern, onIdent) {
for (
let propIndex = 0, len = pattern.properties.length;
propIndex < len;
propIndex++
) {
const prop = pattern.properties[propIndex];
this.enterPattern(prop, onIdent);
}
}
enterArrayPattern(pattern, onIdent) {
for (
let elementIndex = 0, len = pattern.elements.length;
elementIndex < len;
elementIndex++
) {
const element = pattern.elements[elementIndex];
this.enterPattern(element, onIdent);
}
}
enterRestElement(pattern, onIdent) {
this.enterPattern(pattern.argument, onIdent);
}
enterAssignmentPattern(pattern, onIdent) {
this.enterPattern(pattern.left, onIdent);
}
evaluateExpression(expression) {
try {
const hook = this.hooks.evaluate.get(expression.type);
if (hook !== undefined) {
const result = hook.call(expression);
if (result !== undefined) {
if (result) {
result.setExpression(expression);
}
return result;
}
}
} catch (e) {
console.warn(e);
// ignore error
}
return new BasicEvaluatedExpression()
.setRange(expression.range)
.setExpression(expression);
}
parseString(expression) {
switch (expression.type) {
case "BinaryExpression":
if (expression.operator === "+") {
return (
this.parseString(expression.left) +
this.parseString(expression.right)
);
}
break;
case "Literal":
return expression.value + "";
}
throw new Error(
expression.type + " is not supported as parameter for require"
);
}
parseCalculatedString(expression) {
switch (expression.type) {
case "BinaryExpression":
if (expression.operator === "+") {
const left = this.parseCalculatedString(expression.left);
const right = this.parseCalculatedString(expression.right);
if (left.code) {
return {
range: left.range,
value: left.value,
code: true,
conditional: false
};
} else if (right.code) {
return {
range: [
left.range[0],
right.range ? right.range[1] : left.range[1]
],
value: left.value + right.value,
code: true,
conditional: false
};
} else {
return {
range: [left.range[0], right.range[1]],
value: left.value + right.value,
code: false,
conditional: false
};
}
}
break;
case "ConditionalExpression": {
const consequent = this.parseCalculatedString(expression.consequent);
const alternate = this.parseCalculatedString(expression.alternate);
const items = [];
if (consequent.conditional) {
items.push(...consequent.conditional);
} else if (!consequent.code) {
items.push(consequent);
} else {
break;
}
if (alternate.conditional) {
items.push(...alternate.conditional);
} else if (!alternate.code) {
items.push(alternate);
} else {
break;
}
return {
range: undefined,
value: "",
code: true,
conditional: items
};
}
case "Literal":
return {
range: expression.range,
value: expression.value + "",
code: false,
conditional: false
};
}
return {
range: undefined,
value: "",
code: true,
conditional: false
};
}
parse(source, initialState) {
let ast;
let comments;
if (typeof source === "object" && source !== null) {
ast = source;
comments = source.comments;
} else {
comments = [];
ast = JavascriptParser.parse(source, {
sourceType: this.sourceType,
onComment: comments
});
}
const oldScope = this.scope;
const oldState = this.state;
const oldComments = this.comments;
this.scope = {
topLevelScope: true,
inTry: false,
inShorthand: false,
isStrict: false,
definitions: new StackedSetMap(),
renames: new StackedSetMap()
};
const state = (this.state = initialState || {});
this.comments = comments;
if (this.hooks.program.call(ast, comments) === undefined) {
this.detectStrictMode(ast.body);
this.prewalkStatements(ast.body);
this.blockPrewalkStatements(ast.body);
this.walkStatements(ast.body);
}
this.scope = oldScope;
this.state = oldState;
this.comments = oldComments;
return state;
}
evaluate(source) {
const ast = JavascriptParser.parse("(" + source + ")", {
sourceType: this.sourceType,
locations: false
});
// TODO(https://github.com/acornjs/acorn/issues/741)
// @ts-ignore
if (ast.body.length !== 1 || ast.body[0].type !== "ExpressionStatement") {
throw new Error("evaluate: Source is not a expression");
}
// TODO(https://github.com/acornjs/acorn/issues/741)
// @ts-ignore
return this.evaluateExpression(ast.body[0].expression);
}
getComments(range) {
return this.comments.filter(
comment => comment.range[0] >= range[0] && comment.range[1] <= range[1]
);
}
parseCommentOptions(range) {
const comments = this.getComments(range);
if (comments.length === 0) {
return EMPTY_COMMENT_OPTIONS;
}
let options = {};
let errors = [];
for (const comment of comments) {
const { value } = comment;
if (value && webpackCommentRegExp.test(value)) {
// try compile only if webpack options comment is present
try {
const val = vm.runInNewContext(`(function(){return {${value}};})()`);
Object.assign(options, val);
} catch (e) {
e.comment = comment;
errors.push(e);
}
}
}
return { options, errors };
}
getNameForExpression(expression) {
let expr = expression;
const exprName = [];
while (
expr.type === "MemberExpression" &&
expr.property.type === (expr.computed ? "Literal" : "Identifier")
) {
exprName.push(
expr.computed ? `${expr.property.value}` : expr.property.name
);
expr = expr.object;
}
let free;
let rootRaw;
if (expr.type === "Identifier") {
free = !this.scope.definitions.has(expr.name);
exprName.push(this.scope.renames.get(expr.name) || expr.name);
rootRaw = expr.name;
} else if (expr.type === "ThisExpression") {
const rename = this.scope.renames.get("this");
if (rename) {
free = true;
exprName.push(rename);
} else {
free = !!this.scope.topLevelScope;
exprName.push("this");
}
rootRaw = "this";
} else {
return null;
}
let prefix = "";
for (let i = exprName.length - 1; i >= 2; i--) {
prefix += exprName[i] + ".";
}
if (exprName.length > 1) {
prefix += exprName[1];
}
const name = prefix ? prefix + "." + exprName[0] : exprName[0];
const nameGeneral = prefix;
const rootName = exprName.pop();
return {
name,
nameGeneral,
rootName,
rootRaw,
members: exprName.reverse(),
free
};
}
static parse(code, options) {
const type = options ? options.sourceType : "module";
const parserOptions = {
...defaultParserOptions,
...options
};
if (type === "auto") {
parserOptions.sourceType = "module";
} else if (parserOptions.sourceType === "script") {
parserOptions.allowReturnOutsideFunction = true;
}
let ast;
let error;
let threw = false;
try {
ast = parser.parse(code, parserOptions);
} catch (e) {
error = e;
threw = true;
}
if (threw && type === "auto") {
parserOptions.sourceType = "script";
parserOptions.allowReturnOutsideFunction = true;
if (Array.isArray(parserOptions.onComment)) {
parserOptions.onComment.length = 0;
}
try {
ast = parser.parse(code, parserOptions);
threw = false;
} catch (e) {
threw = true;
}
}
if (threw) {
throw error;
}
return ast;
}
}
module.exports = JavascriptParser;