Merge pull request #176 from heroku/env-plus-env-dir

test and implementation for taking env vars from either the environment ...

bin/compile

@@ -26,10 +26,10 @@ unset GIT_DIR
 # Provide hook to deal with errors
 trap build_failed ERR
 
-# Load config vars into environment; start with defaults
-export NPM_CONFIG_PRODUCTION=true
-export NODE_MODULES_CACHE=true
+# Load config vars into environment; set smart defaults
 export_env_dir $env_dir
+export NPM_CONFIG_PRODUCTION=${NPM_CONFIG_PRODUCTION:-true}
+export NODE_MODULES_CACHE=${NODE_MODULES_CACHE:-true}
 
 ####### Determine current state
 

bin/test

@@ -214,6 +214,17 @@ testNoEnvVars() {
   assertCapturedSuccess
 }
 
+testNonFileEnvVars() {
+  export NPM_CONFIG_FOO=bar
+  export NPM_CONFIG_PRODUCTION=false
+  compile "stable-node"
+  assertCaptured "NPM_CONFIG_FOO=bar"
+  assertCaptured "NPM_CONFIG_PRODUCTION=false"
+  assertCapturedSuccess
+  unset NPM_CONFIG_FOO
+  unset NPM_CONFIG_PRODUCTION
+}
+
 testNoDevDependencies() {
   compile "dev-dependencies"
   assertNotCaptured "lodash"