Initial implementation of a new parser (#209)

This patch includes the following things:
  - Implement reading WebIDL files as IDL fragments in parallel.
  - Introduce a new parser to process individual IDL fragment.
    In this patch, it just creates AST(Abstract Syntax Tree) for now
    by using WebIDL2 parser.
  - Add `base/` and `new_parsaer/` to lint target list.

ISSUE=#207

docs/webidl_compiler.md

@@ -35,3 +35,18 @@ internally.
 ### WebIDL compiler
 The WebIDL compiler(or often we called bindings generator) transcompiles WebIDL
 to Native codes such as C++ codes.
+
+## Reading/Processing IDL Files in parallel
+When reading/processing a single IDL file, it should be each independent task.
+Then, we can extend our compiler easily to support multi-threading or
+distributed compiling in the future.
+
+## Parsing WebIDL
+The parsing step is corresponding to the front-end part of compiler. The goal in
+this step, is that creating IDL definition objects as intermediated results.
+
+### Creating AST(Abstract Syntax Tree)
+To parse WebIDL(exactly,
+[IDL Fragment](https://heycam.github.io/webidl/#dfn-idl-fragment)),
+we just use [WebIDL2 parser](https://github.com/w3c/webidl2.js). It provides a
+trivial API called parse(). If we use the API, the WebIDL2 parser returns a AST.

generator/index.ts

@@ -14,14 +14,25 @@
  * limitations under the License.
  */
 
-import * as assert from 'assert';
+import * as file from 'generator/base/file';
+import {Parser} from 'generator/new_parser/parser';
 
-export async function run(idlFiles: string[]): Promise<number> {
-  assert(idlFiles.indexOf('test/test_interface.idl') >= 0);
-  assert(idlFiles.indexOf('examples/calculator.idl') >= 0);
-  assert(idlFiles.indexOf('examples/electron/native/electron_native.idl') >= 0);
+async function processIDL(idlFilePath: string): Promise<void> {
+  const idlFragment: string = await file.read(idlFilePath);
+  await Parser.parse(idlFragment);
+}
+
+export async function run(idlFilePaths: string[]): Promise<number> {
+  const readIDLFileTasks: Promise<void>[] = [];
+  idlFilePaths.forEach((idlFilePath) => {
+    readIDLFileTasks.push(processIDL(idlFilePath));
+  });
 
-  // Not implemented yet.
+  try {
+    await Promise.all(readIDLFileTasks);
+  } catch (e) {
+    return e;
+  }
 
   return 0;
 }

generator/new_parser/parser.ts

@@ -0,0 +1,29 @@
+/**
+ * Copyright (c) 2017 The Bacardi Authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import * as webidl from 'webidl2';
+
+/**
+ * WebIDL Parser
+ */
+export class Parser {
+  public static async parse(idlFragment: string):
+      Promise<void> {
+    const astData: {}[] = webidl.parse(idlFragment);
+
+    // Not implemented yet.
+  }
+}

gulpfile.ts

@@ -113,7 +113,9 @@ gulp.task('lint_ts', () => {
 
   return gulp.src([
         'gulpfile.ts',
-        'generator/index.ts'
+        'generator/index.ts',
+        'generator/base/**/*.ts',
+        'generator/new_parser/**/*.ts'
       ])
       .pipe(gulpTslint({
           formatter: 'codeFrame',
@@ -129,7 +131,9 @@ gulp.task('lint_ts:fix', () => {
 
   return gulp.src([
         'gulpfile.ts',
-        'generator/index.ts'
+        'generator/index.ts',
+        'generator/base/**/*.ts',
+        'generator/new_parser/**/*.ts'
       ])
       .pipe(gulpTslint({
           formatter: 'codeFrame',

tslint.json

@@ -2,11 +2,18 @@
   "extends": "tslint-microsoft-contrib",
   "rules": {
     "export-name": false,
+    "function-name": false,
     "indent": [true, 2],
     "match-default-export-name": false,
     "max-line-length": [true, 80],
+    "no-stateless-class": false,
     "no-suspicious-comment": false,
     "no-unsafe-any": false,
+    "strict-boolean-expressions": [
+      true,
+      "allow-null-union",
+      "allow-undefined-union"
+    ],
     "typedef": [
       true,
       "call-signature",