Add ExternalResolver to filter modules which should not be processed

lib/cli/convert.js

@@ -6,9 +6,8 @@ var Path = require('path');
 var recast = require('recast');
 
 var formatters = require('../formatters');
-var FileResolver = require('../file_resolver');
+var resolvers = require('../resolvers');
 var Container = require('../container');
-var FileResolver = require('../file_resolver');
 
 var getopt = require('posix-getopt');
 var exe = Path.basename(process.argv[1]);
@@ -20,10 +19,11 @@ exports.run = function(args, puts, eputs) {
   var includePaths = [process.cwd()];
   var output;
   var formatter = formatters[formatters.DEFAULT];
-  var resolverClasses = [FileResolver];
+  var resolverClasses = [resolvers.file];
+  var ignoreExternal = false;
 
   while (offset < args.length) {
-    var parser = new getopt.BasicParser('h(help)o:(output)I:(include)f:(format)r:(resolver)', ['', ''].concat(args.slice(offset)));
+    var parser = new getopt.BasicParser('h(help)o:(output)I:(include)f:(format)r:(resolver)e(external)', ['', ''].concat(args.slice(offset)));
     var option;
 
     while ((option = parser.getopt()) !== undefined) {
@@ -73,6 +73,10 @@ exports.run = function(args, puts, eputs) {
             return 1;
           }
           break;
+
+        case 'e':
+          ignoreExternal = true;
+          break;
       }
     }
 
@@ -90,14 +94,17 @@ exports.run = function(args, puts, eputs) {
     formatter = new formatter();
   }
 
-  var resolvers = resolverClasses.map(function(resolverClass) {
-    return new resolverClass(includePaths);
-  });
   var container = new Container({
     formatter: formatter,
-    resolvers: resolvers
+    resolvers: resolverClasses.map(function(resolverClass) {
+      return new resolverClass(includePaths);
+    })
   });
 
+  if (ignoreExternal) {
+      container.resolvers.push(new resolvers.external());
+  }
+
   files.forEach(function(file) {
     container.getModule(file);
   });
@@ -134,6 +141,7 @@ function usage(puts) {
   puts('  -o, --output <path>       File or directory to output converted files.');
   puts('  -f, --format <path|name>  Path to custom formatter or choose from built-in formats.');
   puts('  -r, --resolver <path>     Path to custom resolver (usable multiple times).');
+  puts('  -e, --external            Flag to ignore external modules from parsing/validation.');
   puts('  -h, --help                Show this help message.');
   puts();
   puts(bold('Formats'));

lib/container.js

@@ -176,6 +176,8 @@ Container.prototype.getModules = function() {
   var modules = this.modules;
   return Object.keys(modules).map(function(key) {
     return modules[key];
+  }).filter(function (module) {
+    return !module.external;
   });
 };
 

lib/index.js

@@ -1,9 +1,9 @@
 /* jshint node:true, undef:true, unused:true */
 
 var Container = require('./container');
-var FileResolver = require('./file_resolver');
 var formatters = require('./formatters');
+var resolvers = require('./resolvers');
 
-exports.FileResolver = FileResolver;
 exports.Container = Container;
 exports.formatters = formatters;
+exports.resolvers = resolvers;

lib/resolvers.js

@@ -0,0 +1,4 @@
+/* jshint node:true, undef:true, unused:true */
+
+exports.file = require('./resolvers/file_resolver');
+exports.external = require('./resolvers/external_resolver');

lib/resolvers/external_resolver.js

@@ -0,0 +1,50 @@
+/* jshint node:true, undef:true, unused:true */
+
+var Module = require('../module');
+
+/**
+ * Provides "mock" Module object for external modules which should be ignored.
+ *
+ * @constructor
+ */
+function ExternalResolver(externalModules) {
+  // When `externalModules` is specificed, restrict to modules named in list.
+  if (Array.isArray(externalModules) && externalModules.length) {
+      this.externalModules = externalModules;
+  }
+}
+
+/**
+ * Resolves `importedPath` imported by the given module `fromModule` to a
+ * an external module.
+ *
+ * @param {string} importedPath
+ * @param {?Module} fromModule
+ * @param {Container} container
+ * @return {?Module}
+ */
+ExternalResolver.prototype.resolveModule = function (importedPath, fromModule, container) {
+  var isExternal, module;
+
+  if (this.externalModules) {
+      isExternal = this.externalModules.indexOf(importedPath) >= 0;
+  } else {
+      isExternal = importedPath.charAt(0) !== '.';
+  }
+
+  if (isExternal) {
+      module = container.getCachedModule(importedPath);
+
+      if (!module) {
+        module = new Module(importedPath, importedPath, container);
+        module.external = true;
+        console.log('INFO: External module detected: "%s"', importedPath);
+      }
+
+      return module;
+  }
+
+  return null;
+};
+
+module.exports = ExternalResolver;

lib/file_resolver.js → lib/resolvers/file_resolver.js

@@ -4,7 +4,7 @@ var assert = require('assert');
 var Path = require('path');
 var fs = require('fs');
 
-var Module = require('./module');
+var Module = require('../module');
 
 /**
  * Provides resolution of absolute paths from module import sources.

test/runner.js

@@ -90,7 +90,7 @@ function runTestDir(testDir) {
   var testName = Path.basename(testDir);
 
   var options = {
-    resolvers: [new modules.FileResolver([testDir])],
+    resolvers: [new modules.resolvers.file([testDir])],
     formatter: formatters[formatter]
   };
   var container = new modules.Container(options);