webpack/lib/Chunk.js

Packs CommonJs/AMD modules for the browser. Allows to split your codebase into multiple bundles, which can be loaded on demand. Support loaders to preprocess files, i.e. json, jade, coffee, css, less, ... and your custom stuff.

/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Tobias Koppers @sokra
*/
function Chunk(name, module, loc) {
	this.id = null;
	this.ids = null;
	this.name = name;
	this.modules = [];
	this.chunks = [];
	this.parents = [];
	this.blocks = [];
	this.origins = [];
	this.rendered = false;
	this.entry = false;
	this.initial = false;
	if(module) {
		this.origins.push({
			module: module,
			loc: loc,
			name: name
		});
	}
}
module.exports = Chunk;

Chunk.prototype.addModule = function(module) {
	if(this.modules.indexOf(module) >= 0) {
		return false;
	}
	this.modules.push(module);
	return true;
};

Chunk.prototype._removeAndDo = require("./removeAndDo");

Chunk.prototype.removeModule = function(module) {
	this._removeAndDo("modules", module, "removeChunk");
};

Chunk.prototype.removeChunk = function(chunk) {
	this._removeAndDo("chunks", chunk, "removeParent");
};

Chunk.prototype.removeParent = function(chunk) {
	this._removeAndDo("parents", chunk, "removeChunk");
};

function createAdder(collection) {
	return function(chunk) {
		if(chunk === this) {
			return false;
		}
		if(this[collection].indexOf(chunk) >= 0) {
			return false;
		}
		this[collection].push(chunk);
		return true;
	};
}

Chunk.prototype.addChunk = createAdder("chunks");

Chunk.prototype.addParent = createAdder("parents");

Chunk.prototype.addBlock = function(block) {
	if(this.blocks.indexOf(block) >= 0) {
		return false;
	}
	this.blocks.push(block);
	return true;
};

Chunk.prototype.addOrigin = function(module, loc) {
	this.origins.push({module: module, loc: loc, name: this.name});
};

Chunk.prototype.remove = function(reason) {
	this.modules.slice().forEach(function(m) {
		m.removeChunk(this);
	}, this);
	this.parents.forEach(function(c) {
		var idx = c.chunks.indexOf(this);
		if(idx >= 0) {
			c.chunks.splice(idx, 1);
		}
		this.chunks.forEach(function(cc) {
			cc.addParent(c);
		});
	}, this);
	this.chunks.forEach(function(c) {
		var idx = c.parents.indexOf(this);
		if(idx >= 0) {
			c.parents.splice(idx, 1);
		}
		this.parents.forEach(function(cc) {
			cc.addChunk(c);
		});
	}, this);
	this.blocks.forEach(function(b) {
		b.chunk = null;
		b.chunkReason = reason;
	}, this);
};

Chunk.prototype.integrate = function(other, reason) {
	if(!this.canBeIntegrated(other)) {
		return false;
	}

	var otherModules = other.modules.slice();
	otherModules.forEach(function(m) {
		m.removeChunk(other);
		m.addChunk(this);
		this.addModule(m);
		m.rewriteChunkInReasons(other, [this]);
	}, this);
	other.modules.length = 0;
	function moveChunks(chunks, kind, onChunk) {
		chunks.forEach(function(c) {
			var idx = c[kind].indexOf(other);
			if(idx >= 0) {
				c[kind].splice(idx, 1);
			}
			onChunk(c);
		});
	}
	moveChunks(other.parents, "chunks", function(c) {
		if(c !== this && this.addParent(c)) {
			c.addChunk(this);
		}
	}.bind(this));
	other.parents.length = 0;
	moveChunks(other.chunks, "parents", function(c) {
		if(c !== this && this.addChunk(c)) {
			c.addParent(this);
		}
	}.bind(this));
	other.chunks.length = 0;
	other.blocks.forEach(function(b) {
		b.chunk = this;
		b.chunkReason = reason;
		this.addBlock(b);
	}, this);
	other.blocks.length = 0;
	other.origins.forEach(function(origin) {
		if(!origin.reasons) {
			origin.reasons = [reason];
		} else if(origin.reasons[0] !== reason) {
			origin.reasons.unshift(reason);
		}
		this.origins.push(origin);
	}, this);
	return true;
};

Chunk.prototype.isEmpty = function() {
	return (this.modules.length === 0);
};

Chunk.prototype.updateHash = function(hash) {
	hash.update(this.id + " ");
	hash.update(this.ids ? this.ids.join(",") : "");
	hash.update(this.name + "");
	this.modules.forEach(function(m) {
		m.updateHash(hash);
	});
};

Chunk.prototype.size = function(options) {
	var CHUNK_OVERHEAD = options.chunkOverhead || 10000;
	var ENTRY_CHUNK_MULTIPLICATOR = options.entryChunkMultiplicator || 10;

	var modulesSize = this.modules.map(function(m) {
		return m.size();
	}).reduce(function(a, b) {
		return a + b;
	}, 0);
	return modulesSize * (this.initial ? ENTRY_CHUNK_MULTIPLICATOR : 1) + CHUNK_OVERHEAD;
};

Chunk.prototype.canBeIntegrated = function(other) {
	if(other.initial) {
		return false;
	}
	if(this.initial) {
		if(other.parents.length !== 1 || other.parents[0] !== this) {
			return false;
		}
	}
	return true;
};

Chunk.prototype.integratedSize = function(other, options) {
	// Chunk if it's possible to integrate this chunks
	if(!this.canBeIntegrated(other)) {
		return false;
	}

	var CHUNK_OVERHEAD = options.chunkOverhead || 10000;
	var ENTRY_CHUNK_MULTIPLICATOR = options.entryChunkMultiplicator || 10;

	var mergedModules = this.modules.slice();
	other.modules.forEach(function(m) {
		if(this.modules.indexOf(m) < 0) {
			mergedModules.push(m);
		}
	}, this);

	var modulesSize = mergedModules.map(function(m) {
		return m.size();
	}).reduce(function(a, b) {
		return a + b;
	}, 0);
	return modulesSize * (this.initial || other.initial ? ENTRY_CHUNK_MULTIPLICATOR : 1) + CHUNK_OVERHEAD;
};

Chunk.prototype.toString = function() {
	return "Chunk[" + this.modules.join() + "]";
};