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sunderls · Apr 6, 2017 · 6d1955d · 6d1955d
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Showing 7 changed files with 175 additions and 3 deletions.
diff --git a/.gitignore b/.gitignore
@@ -0,0 +1 @@
+node_modules
diff --git a/example/dist/bundle.js b/example/dist/bundle.js
@@ -0,0 +1,42 @@
+
+(function(moduleFactories) {
+	// all modules should be instantiated lazily
+	var modules = [];
+
+	function require(id) {
+		if (modules[id]) {
+			return modules[id];
+		} else {
+			var m = moduleFactories[id]({}, require);
+			modules.push(m);
+			return modules[id];
+		}
+	}
+
+	// kick 
+	require(2);
+})([function(exports, require){
+exports.log = function(){
+    console.log('ModuleB log()');
+}
+
+return exports; }
+,function(exports, require){
+var logB = require(0)['log'];
+
+exports.default = {
+    log() {
+        console.log('ModuleA log()');
+        logB();
+    }
+}
+
+return exports; }
+,function(exports, require){
+var A = require(1)['default'];
+
+console.log('in enty js');
+A.log();
+
+return exports; }
+])
diff --git a/example/dist/index.html b/example/dist/index.html
@@ -0,0 +1,9 @@
+<!DOCTYPE html>
+<html>
+<head>
+	<title>lspack demo</title>
+</head>
+<body>
+<script src="./bundle.js"></script>
+</body>
+</html>
diff --git a/example/lspack.config.js b/example/lspack.config.js
@@ -1,4 +1,4 @@
-{
+module.exports = {
 	entry: './src/index.js',
 	output: './dist/bundle.js'
 }
diff --git a/example/src/moduleB.js b/example/src/moduleB.js
@@ -1,3 +1,3 @@
-export log = () => {
+export function log(){
 	console.log('ModuleB log()');
 }
diff --git a/index.js b/index.js
@@ -0,0 +1,114 @@
+#!/usr/bin/env node
+const fs = require('fs');
+const path = require('path');
+const esprima = require('esprima');
+const escodegen = require('escodegen');
+
+
+// add .js to modulePath if not there
+// support only relative paths now
+const resolveModulePath = (modulePath, relativeTo = '.') => {
+	return path.resolve(relativeTo, /\.\w+$/.test(modulePath) ? modulePath : modulePath + '.js');
+}
+
+const modulePaths = [];
+const moduleTexts = [];
+
+// get module's ID
+// push into modules if not found
+const getModuleId = (modulePath) => {
+	const id = modulePaths.indexOf(modulePath);
+	if (id === -1) {
+		return transform(modulePath);
+	}
+
+	return id;
+}
+
+// transform a file to module
+// 1. read file text
+// 2. get imports & transform recursively
+// 3. return index
+const transform = (modulePath) => {
+	const transformedResult = [
+		'function(exports, require){'
+	];
+
+	// read file from entry
+	const fileText = fs.readFileSync(modulePath, {
+		encoding: 'utf8'
+	});
+
+	// use esprima to detect import statement
+	const program = esprima.parse(fileText, { sourceType: 'module'});
+
+	// handle import & export
+	program.body.forEach(line => {
+		switch (line.type) {
+		case 'ImportDeclaration': 
+			const id = getModuleId(resolveModulePath(line.source.value, path.dirname(modulePath)));
+
+			line.specifiers.forEach(specifier => {
+				// [TODO] more types
+				switch (specifier.type) {
+					case 'ImportDefaultSpecifier':
+						transformedResult.push(`var ${specifier.local.name} = require(${id})['default'];\n`);
+						break;
+					case 'ImportSpecifier':
+						transformedResult.push(`var ${specifier.local.name} = require(${id})['${specifier.imported.name}'];\n`);
+						break;
+				}
+			});
+			break;
+		case 'ExportDefaultDeclaration': 
+			// export default {}
+			if (line.declaration.type === 'ObjectExpression') {
+				transformedResult.push(`exports.default = ${escodegen.generate(line.declaration)}`);
+				break;
+			}
+		case 'ExportNamedDeclaration':
+			if (line.declaration.type === 'FunctionDeclaration') {
+				transformedResult.push(`exports.${line.declaration.id.name} = function()${escodegen.generate(line.declaration.body)}`);
+				break;
+			}
+		// [TODO] more types
+		default:
+			transformedResult.push(escodegen.generate(line));
+		}
+	});
+	transformedResult.push('\nreturn exports; }\n');
+
+	moduleTexts.push(transformedResult.join('\n'));
+	modulePaths.push(modulePath);
+	return moduleTexts.length - 1;
+};
+
+
+
+// read lspack.config.js and parse
+const config = require(path.resolve('./lspack.config.js'));
+const entryModuleId = transform(resolveModulePath(config.entry));
+
+// we've get all modules, now bootstrap
+const bundle = `
+(function(moduleFactories) {
+	// all modules should be instantiated lazily
+	var modules = [];
+
+	function require(id) {
+		if (modules[id]) {
+			return modules[id];
+		} else {
+			var m = moduleFactories[id]({}, require);
+			modules.push(m);
+			return modules[id];
+		}
+	}
+
+	// kick 
+	require(${entryModuleId});
+})([${moduleTexts.join(',')}])
+`;
+
+// write to dist
+fs.writeFileSync(config.output, bundle);
diff --git a/package.json b/package.json
@@ -3,6 +3,7 @@
   "version": "0.0.1",
   "description": "lspack",
   "main": "index.js",
+  "bin": "./index.js",
   "scripts": {
     "test": "echo \"Error: no test specified\" && exit 1"
   },
@@ -15,5 +16,10 @@
   "bugs": {
     "url": "https://github.com/sunderls/lspack/issues"
   },
-  "homepage": "https://github.com/sunderls/lspack#readme"
+  "homepage": "https://github.com/sunderls/lspack#readme",
+  "devDependencies": {
+    "escodegen": "^1.8.1",
+    "esprima": "^3.1.3",
+    "npm": "^4.4.4"
+  }
 }