Merge 64a01aa into e0a5425

lib/run-context.js

@@ -76,7 +76,10 @@ RunContext.prototype._run = function() {
 
   this.ran = true;
   var namespace;
-  this.env = yeoman.createEnv([], {}, new TestAdapter());
+  this.env = (this.envCB || (env => env)).call(
+    this,
+    yeoman.createEnv([], {}, new TestAdapter())
+  );
 
   helpers.registerDependencies(this.env, this.dependencies);
 
@@ -209,6 +212,20 @@ RunContext.prototype.inTmpDir = function(cb) {
   return this.inDir(tmpdir, cb);
 };
 
+/**
+ * Create an environment
+ *
+ * This method is called automatically when creating a RunContext. Only use it if you need
+ * to use the callback.
+ *
+ * @param {Function} [cb] - callback who'll receive the folder path as argument
+ * @return {this} run context instance
+ */
+RunContext.prototype.withEnvironment = function(cb = env => env) {
+  this.envCB = cb;
+  return this;
+};
+
 /**
  * Clean the directory used for tests inside inDir/inTmpDir
  */