refactor(@embark/compiler): refactor/simplify compiler module

src/lib/modules/compiler/index.ts

@@ -1,11 +1,6 @@
 const async = require("../../utils/async_extend.js");
 import { Embark } from "../../../typings/embark";
-import { Plugins } from "../../../typings/plugins";
-
-interface CompilerPluginObject {
-  extension: string;
-  cb: any;
-}
+import { CompilerPluginObject, Plugins } from "../../../typings/plugins";
 
 class Compiler {
   private logger: any;
@@ -21,52 +16,56 @@ class Compiler {
   }
 
   private compile_contracts(contractFiles: any[], options: any, cb: any) {
-    const available_compilers: { [index:string] : any } = {};
-
     if (contractFiles.length === 0) {
       return cb(null, {});
     }
 
-    this.plugins.getPluginsProperty("compilers", "compilers").forEach((compilerObject: CompilerPluginObject) => {
-      available_compilers[compilerObject.extension] = compilerObject.cb;
-    });
-
-    const compiledObject: { [index:string] : any } = {};
+    const compiledObject: {[index: string]: any} = {};
 
     const compilerOptions = {
       disableOptimizations: this.disableOptimizations || options.disableOptimizations,
     };
 
-    async.eachObject(available_compilers,
-      (extension: string, compiler: any, callback: any) => {
-        const matchingFiles = contractFiles.filter((file: any) => {
-          const fileMatch = file.filename.match(/\.[0-9a-z]+$/);
-          if (fileMatch && (fileMatch[0] === extension)) {
-            file.compiled = true;
-            return true;
+    async.eachObject(this.getAvailableCompilers(),
+      (extension: string, compiler: any, next: any) => {
+        const matchingFiles = contractFiles.filter(this.filesMatchingExtension(extension));
+        if (matchingFiles.length === 0) {
+          return next();
         }
-          return false;
-        });
 
-        if (!matchingFiles || !matchingFiles.length) {
-          return callback();
-        }
         compiler.call(compiler, matchingFiles, compilerOptions, (err: any, compileResult: any) => {
           Object.assign(compiledObject, compileResult);
-          callback(err, compileResult);
+          next(err, compileResult);
         });
       },
       (err: any) => {
-        contractFiles.forEach((file: any) => {
-          if (!file.compiled) {
+        contractFiles.filter((f: any) => !f.compiled).forEach((file: any) => {
           this.logger.warn(__("%s doesn't have a compatible contract compiler. Maybe a plugin exists for it.", file.filename));
-          }
         });
 
         cb(err, compiledObject);
       },
     );
   }
+
+  private getAvailableCompilers() {
+    const available_compilers: { [index: string]: any } = {};
+    this.plugins.getPluginsProperty("compilers", "compilers").forEach((compilerObject: CompilerPluginObject) => {
+      available_compilers[compilerObject.extension] = compilerObject.cb;
+    });
+    return available_compilers;
+  }
+
+  private filesMatchingExtension(extension: string) {
+    return (file: any) => {
+      const fileMatch = file.filename.match(/\.[0-9a-z]+$/);
+      if (fileMatch && (fileMatch[0] === extension)) {
+        file.compiled = true;
+        return true;
+      }
+      return false;
+    };
+  }
 }
 
 module.exports = Compiler;

src/typings/plugins.d.ts

@@ -7,3 +7,8 @@ export interface Plugins {
   loadInternalPlugin(name: string, options: any): void;
   getPluginsProperty(prop: string, name: string): any[];
 }
+
+export interface CompilerPluginObject {
+  extension: string;
+  cb: any;
+}