gree_leran/node_modules/webpack/lib/optimize/InnerGraph.js

352 lines
9.2 KiB
JavaScript

/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Sergey Melyukov @smelukov
*/
"use strict";
const { UsageState } = require("../ExportsInfo");
/** @typedef {import("estree").Node} AnyNode */
/** @typedef {import("../Dependency")} Dependency */
/** @typedef {import("../Module")} Module */
/** @typedef {import("../ModuleGraph")} ModuleGraph */
/** @typedef {import("../ModuleGraphConnection")} ModuleGraphConnection */
/** @typedef {import("../ModuleGraphConnection").ConnectionState} ConnectionState */
/** @typedef {import("../Parser").ParserState} ParserState */
/** @typedef {import("../javascript/JavascriptParser")} JavascriptParser */
/** @typedef {import("../util/runtime").RuntimeSpec} RuntimeSpec */
/** @typedef {Map<TopLevelSymbol | null, Set<string | TopLevelSymbol> | true | undefined>} InnerGraph */
/** @typedef {function(boolean | Set<string> | undefined): void} UsageCallback */
/**
* @typedef {Object} StateObject
* @property {InnerGraph} innerGraph
* @property {TopLevelSymbol=} currentTopLevelSymbol
* @property {Map<TopLevelSymbol, Set<UsageCallback>>} usageCallbackMap
*/
/** @typedef {false|StateObject} State */
/** @type {WeakMap<ParserState, State>} */
const parserStateMap = new WeakMap();
const topLevelSymbolTag = Symbol("top level symbol");
/**
* @param {ParserState} parserState parser state
* @returns {State | undefined} state
*/
function getState(parserState) {
return parserStateMap.get(parserState);
}
/**
* @param {ParserState} parserState parser state
* @returns {void}
*/
exports.bailout = parserState => {
parserStateMap.set(parserState, false);
};
/**
* @param {ParserState} parserState parser state
* @returns {void}
*/
exports.enable = parserState => {
const state = parserStateMap.get(parserState);
if (state === false) {
return;
}
parserStateMap.set(parserState, {
innerGraph: new Map(),
currentTopLevelSymbol: undefined,
usageCallbackMap: new Map()
});
};
/**
* @param {ParserState} parserState parser state
* @returns {boolean} true, when enabled
*/
exports.isEnabled = parserState => {
const state = parserStateMap.get(parserState);
return !!state;
};
/**
* @param {ParserState} state parser state
* @param {TopLevelSymbol | null} symbol the symbol, or null for all symbols
* @param {string | TopLevelSymbol | true} usage usage data
* @returns {void}
*/
exports.addUsage = (state, symbol, usage) => {
const innerGraphState = getState(state);
if (innerGraphState) {
const { innerGraph } = innerGraphState;
const info = innerGraph.get(symbol);
if (usage === true) {
innerGraph.set(symbol, true);
} else if (info === undefined) {
innerGraph.set(symbol, new Set([usage]));
} else if (info !== true) {
info.add(usage);
}
}
};
/**
* @param {JavascriptParser} parser the parser
* @param {string} name name of variable
* @param {string | TopLevelSymbol | true} usage usage data
* @returns {void}
*/
exports.addVariableUsage = (parser, name, usage) => {
const symbol =
/** @type {TopLevelSymbol} */ (
parser.getTagData(name, topLevelSymbolTag)
) || exports.tagTopLevelSymbol(parser, name);
if (symbol) {
exports.addUsage(parser.state, symbol, usage);
}
};
/**
* @param {ParserState} state parser state
* @returns {void}
*/
exports.inferDependencyUsage = state => {
const innerGraphState = getState(state);
if (!innerGraphState) {
return;
}
const { innerGraph, usageCallbackMap } = innerGraphState;
const processed = new Map();
// flatten graph to terminal nodes (string, undefined or true)
const nonTerminal = new Set(innerGraph.keys());
while (nonTerminal.size > 0) {
for (const key of nonTerminal) {
/** @type {Set<string|TopLevelSymbol> | true} */
let newSet = new Set();
let isTerminal = true;
const value = innerGraph.get(key);
let alreadyProcessed = processed.get(key);
if (alreadyProcessed === undefined) {
alreadyProcessed = new Set();
processed.set(key, alreadyProcessed);
}
if (value !== true && value !== undefined) {
for (const item of value) {
alreadyProcessed.add(item);
}
for (const item of value) {
if (typeof item === "string") {
newSet.add(item);
} else {
const itemValue = innerGraph.get(item);
if (itemValue === true) {
newSet = true;
break;
}
if (itemValue !== undefined) {
for (const i of itemValue) {
if (i === key) continue;
if (alreadyProcessed.has(i)) continue;
newSet.add(i);
if (typeof i !== "string") {
isTerminal = false;
}
}
}
}
}
if (newSet === true) {
innerGraph.set(key, true);
} else if (newSet.size === 0) {
innerGraph.set(key, undefined);
} else {
innerGraph.set(key, newSet);
}
}
if (isTerminal) {
nonTerminal.delete(key);
// For the global key, merge with all other keys
if (key === null) {
const globalValue = innerGraph.get(null);
if (globalValue) {
for (const [key, value] of innerGraph) {
if (key !== null && value !== true) {
if (globalValue === true) {
innerGraph.set(key, true);
} else {
const newSet = new Set(value);
for (const item of globalValue) {
newSet.add(item);
}
innerGraph.set(key, newSet);
}
}
}
}
}
}
}
}
/** @type {Map<Dependency, true | Set<string>>} */
for (const [symbol, callbacks] of usageCallbackMap) {
const usage = /** @type {true | Set<string> | undefined} */ (
innerGraph.get(symbol)
);
for (const callback of callbacks) {
callback(usage === undefined ? false : usage);
}
}
};
/**
* @param {ParserState} state parser state
* @param {UsageCallback} onUsageCallback on usage callback
*/
exports.onUsage = (state, onUsageCallback) => {
const innerGraphState = getState(state);
if (innerGraphState) {
const { usageCallbackMap, currentTopLevelSymbol } = innerGraphState;
if (currentTopLevelSymbol) {
let callbacks = usageCallbackMap.get(currentTopLevelSymbol);
if (callbacks === undefined) {
callbacks = new Set();
usageCallbackMap.set(currentTopLevelSymbol, callbacks);
}
callbacks.add(onUsageCallback);
} else {
onUsageCallback(true);
}
} else {
onUsageCallback(undefined);
}
};
/**
* @param {ParserState} state parser state
* @param {TopLevelSymbol | undefined} symbol the symbol
*/
exports.setTopLevelSymbol = (state, symbol) => {
const innerGraphState = getState(state);
if (innerGraphState) {
innerGraphState.currentTopLevelSymbol = symbol;
}
};
/**
* @param {ParserState} state parser state
* @returns {TopLevelSymbol|void} usage data
*/
exports.getTopLevelSymbol = state => {
const innerGraphState = getState(state);
if (innerGraphState) {
return innerGraphState.currentTopLevelSymbol;
}
};
/**
* @param {JavascriptParser} parser parser
* @param {string} name name of variable
* @returns {TopLevelSymbol | undefined} symbol
*/
exports.tagTopLevelSymbol = (parser, name) => {
const innerGraphState = getState(parser.state);
if (!innerGraphState) return;
parser.defineVariable(name);
const existingTag = /** @type {TopLevelSymbol} */ (
parser.getTagData(name, topLevelSymbolTag)
);
if (existingTag) {
return existingTag;
}
const fn = new TopLevelSymbol(name);
parser.tagVariable(name, topLevelSymbolTag, fn);
return fn;
};
/**
* @param {Dependency} dependency the dependency
* @param {Set<string> | boolean} usedByExports usedByExports info
* @param {ModuleGraph} moduleGraph moduleGraph
* @param {RuntimeSpec} runtime runtime
* @returns {boolean} false, when unused. Otherwise true
*/
exports.isDependencyUsedByExports = (
dependency,
usedByExports,
moduleGraph,
runtime
) => {
if (usedByExports === false) return false;
if (usedByExports !== true && usedByExports !== undefined) {
const selfModule =
/** @type {Module} */
(moduleGraph.getParentModule(dependency));
const exportsInfo = moduleGraph.getExportsInfo(selfModule);
let used = false;
for (const exportName of usedByExports) {
if (exportsInfo.getUsed(exportName, runtime) !== UsageState.Unused)
used = true;
}
if (!used) return false;
}
return true;
};
/**
* @param {Dependency} dependency the dependency
* @param {Set<string> | boolean | undefined} usedByExports usedByExports info
* @param {ModuleGraph} moduleGraph moduleGraph
* @returns {null | false | function(ModuleGraphConnection, RuntimeSpec): ConnectionState} function to determine if the connection is active
*/
exports.getDependencyUsedByExportsCondition = (
dependency,
usedByExports,
moduleGraph
) => {
if (usedByExports === false) return false;
if (usedByExports !== true && usedByExports !== undefined) {
const selfModule =
/** @type {Module} */
(moduleGraph.getParentModule(dependency));
const exportsInfo = moduleGraph.getExportsInfo(selfModule);
return (connections, runtime) => {
for (const exportName of usedByExports) {
if (exportsInfo.getUsed(exportName, runtime) !== UsageState.Unused)
return true;
}
return false;
};
}
return null;
};
class TopLevelSymbol {
/**
* @param {string} name name of the variable
*/
constructor(name) {
this.name = name;
}
}
exports.TopLevelSymbol = TopLevelSymbol;
exports.topLevelSymbolTag = topLevelSymbolTag;