webpack/lib/RecordIdsPlugin.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 RecordIdsPlugin() {
}
module.exports = RecordIdsPlugin;
RecordIdsPlugin.prototype.apply = function(compiler) {
	compiler.plugin("compilation", function(compilation) {
		compilation.plugin("record-modules", function(modules, records) {
			records.nextFreeModuleId = compilation.nextFreeModuleId;
			if(!records.modules) records.modules = {};
			if(!records.modules.byIdentifier) records.modules.byIdentifier = {};
			modules.forEach(function(module) {
				var identifier = module.identifier();
				records.modules.byIdentifier[identifier] = module.id;
			});
		});
		compilation.plugin("revive-modules", function(modules, records) {
			if(records.nextFreeModuleId)
				compilation.nextFreeModuleId = records.nextFreeModuleId;
			if(!records.modules || !records.modules.byIdentifier) return;
			var usedIds = {0: true};
			modules.forEach(function(module) {
				if(module.id !== null) return;
				var identifier = module.identifier();
				var id = records.modules.byIdentifier[identifier];
				if(id === undefined) return;
				if(usedIds[id]) return;
				usedIds[id] = true;
				module.id = id;
			});
		});
		
		function getDepBlockIdent(block) {
			var ident = [];
			while(block.parent) {
				var p = block.parent;
				var idx = p.blocks.indexOf(block);
				var l = p.blocks.length - 1;
				ident.unshift(idx + "/" + l);
				block = block.parent;
			}
			if(!block.identifier) return null;
			ident.unshift(block.identifier());
			return ident.join(":");
		}
		compilation.plugin("record-chunks", function(chunks, records) {
			records.nextFreeChunkId = compilation.nextFreeChunkId;
			if(!records.chunks) records.chunks = {};
			if(!records.chunks.byName) records.chunks.byName = {};
			if(!records.chunks.byBlocks) records.chunks.byBlocks = {};
			chunks.forEach(function(chunk) {
				var name = chunk.name;
				var blockIdents = chunk.blocks.map(getDepBlockIdent).filter(Boolean);
				if(name) records.chunks.byName[name] = chunk.id;
				blockIdents.forEach(function(blockIdent) {
					records.chunks.byBlocks[blockIdent] = chunk.id;
				});
			});
		});
		compilation.plugin("revive-chunks", function(chunks, records) {
			if(records.nextFreeChunkId)
				compilation.nextFreeChunkId = records.nextFreeChunkId;
			if(!records.chunks) return;
			var usedIds = {};
			if(records.chunks.byName) {
				chunks.forEach(function(chunk) {
					if(chunk.id !== null) return;
					if(!chunk.name) return;
					var id = records.chunks.byName[chunk.name];
					if(id === undefined) return;
					if(usedIds[id]) return;
					usedIds[id] = true;
					chunk.id = id;
				});
			}
			if(records.chunks.byBlocks) {
				var argumentedChunks = chunks.filter(function(chunk) {
					return chunk.id === null
				}).map(function(chunk) {
					return {
						chunk: chunk,
						blockIdents: chunk.blocks.map(getDepBlockIdent).filter(Boolean)
					}
				}).filter(function(arg) {
					return arg.blockIdents.length > 0;
				});
				var blockIdentsCount = {};
				argumentedChunks.forEach(function(arg, idx) {
					arg.blockIdents.forEach(function(blockIdent) {
						var id = records.chunks.byBlocks[blockIdent]
						if(!id) return;
						var accessor = id + ":" + idx;
						blockIdentsCount[accessor] = (blockIdentsCount[accessor] || 0) + 1;
					});
				});
				blockIdentsCount = Object.keys(blockIdentsCount).map(function(accessor) {
					return [blockIdentsCount[accessor]].concat(accessor.split(":").map(Number));
				}).sort(function(a, b) {
					return b[0] - a[0];
				})
				blockIdentsCount.forEach(function(arg) {
					var id = arg[1];
					if(usedIds[id]) return;
					var idx = arg[2];
					var chunk = argumentedChunks[idx].chunk;
					if(chunk.id !== null) return;
					usedIds[id] = true;
					chunk.id = id;
				});
			}
		});
	});
};