Revert "module: add require.resolve (#445)" (#485)

This reverts commit 7807fe4.
This causes the `require` performance problems.

docs/api/Module.md

@@ -47,12 +47,8 @@ For each directory in search paths above:
   - If `id/package.json` contains **main** property, load the file named **main** property.
   - If `id/package.json` exists, but neither the **main** property nor the file named **main** property exist, load `index.js`.
 
-### require.resolve(request)
-* `request` {string} Module name to be queried.
-
-Get the module absolute path about `request` module but not load it.
-
 ### require.main
 * accessing the main module
 
 When a file is run directly, `require.main` is set to its module. That means that it is possible to determine whether a file has been run directly by testing `require.main === module`. For a file foo.js, this will be true if run via cmd directly, but false if run by `require('./foo')`, because `module` object is set to the `foo` module but `require.main` is still your entry file module. So you can get the entry point of the current application from checking `require.main.filename` anywhere.
+

src/js/module.js

@@ -126,21 +126,18 @@ iotjs_module_t.resolveFilepath = function(id, directories) {
 };
 
 
-iotjs_module_t._resolveFilepath = function(id, root, ext_index) {
+iotjs_module_t._resolveFilepath = function(id, root) {
   var modulePath = root ? path.join(root, id) : id;
   var filepath;
-  var exts = ['.js', '.json', '.node'];
-  if (ext_index === undefined) {
-    ext_index = 0;
-  }
+  var ext = '.js';
 
   // id[.ext]
-  if (filepath = tryPath(modulePath, exts[ext_index])) {
+  if (filepath = tryPath(modulePath, ext)) {
     return filepath;
   }
 
   // id/index[.ext]
-  if (filepath = tryPath(modulePath + '/index', exts[ext_index])) {
+  if (filepath = tryPath(modulePath + '/index', ext)) {
     return filepath;
   }
 
@@ -152,14 +149,10 @@ iotjs_module_t._resolveFilepath = function(id, root, ext_index) {
     var pkgMainFile = JSON.parse(pkgSrc).main;
 
     // pkgmain[.ext]
-    if (filepath = tryPath(modulePath + '/' + pkgMainFile, exts[ext_index])) {
+    if (filepath = tryPath(modulePath + '/' + pkgMainFile, ext)) {
       return filepath;
     }
   }
-  ext_index++;
-  if (ext_index < exts.length) {
-    return iotjs_module_t._resolveFilepath(id, root, ext_index);
-  }
 };
 
 
@@ -278,34 +271,6 @@ iotjs_module_t.load = function(id, parent, isMain) {
   return module.exports;
 };
 
-function _makeRequireFunction(mod) {
-  var Module = mod.constructor;
-  function require(id) {
-    return mod.require(id);
-  }
-
-  function _resolve(request) {
-    if (!request || typeof request !== 'string') {
-      throw new TypeError('module must be a non-null string');
-    }
-
-    if (process.builtin_modules[request]) {
-      return request;
-    }
-
-    var path = Module.resolveModPath(request, mod);
-    if (!path) {
-      throw new Error('Module not found: ' + request);
-    }
-    return path;
-  }
-  require.resolve = _resolve;
-  require.main = mainModule;
-  require.cache = Module.cache;
-
-  return require;
-}
-
 iotjs_module_t.prototype.compile = function(snapshot) {
   var __filename = this.filename;
   var __dirname = path.dirname(__filename);
@@ -318,7 +283,9 @@ iotjs_module_t.prototype.compile = function(snapshot) {
       throw new TypeError('Invalid snapshot file.');
   }
 
-  var _require = _makeRequireFunction(this);
+  var _require = this.require.bind(this);
+  _require.main = mainModule;
+  _require.cache = iotjs_module_t.cache;
 
   fn.apply(this.exports, [
     this.exports,             // exports

test/testsets.json

@@ -122,8 +122,6 @@
     { "name": "test_process_unhandled_rejection.js" },
     { "name": "test_pwm_async.js", "skip": ["all"], "reason": "need to setup test environment" },
     { "name": "test_pwm_sync.js", "skip": ["all"], "reason": "need to setup test environment" },
-    { "name": "test_require_main.js" },
-    { "name": "test_require_resolve.js" },
     { "name": "test_shebang.js" },
     { "name": "test_signal_simple.js" },
     { "name": "test_spi.js", "skip": ["linux"], "reason": "Differend env on Linux desktop/travis/rpi" },