Add resolve tests

Author: TrySound

README.md

@@ -92,17 +92,17 @@ Checkout [tests](test) for more examples.
 #### `root`
 
 Type: `String`  
-Default: `process.cwd()`
+Default: `process.cwd()` or _dirname of [the postcss `from`](https://github.com/postcss/postcss#node-source)_
 
-Define the root where to resolve path (eg: place where `node_modules` are). Should not be used that much.
+Define the root where to resolve path (eg: place where `node_modules` are). Should not be used that much.  
+_Note: nested `@import` will additionally benefit of the relative dirname of imported files._
 
 #### `path`
 
 Type: `String|Array`  
-Default: `process.cwd()` or _dirname of [the postcss `from`](https://github.com/postcss/postcss#node-source)_
+Default: `[]`
 
-A string or an array of paths in where to look for files.  
-_Note: nested `@import` will additionally benefit of the relative dirname of imported files._
+A string or an array of paths in where to look for files.
 
 #### `transform`
 

index.js

@@ -22,8 +22,12 @@ function AtImport(options) {
     options.path = [ options.path ]
   }
 
+  if (!Array.isArray(options.path)) {
+    options.path = []
+  }
+
   options.path = options.path.map(function(p) {
-    return path.resolve(p)
+    return path.resolve(options.root, p)
   })
 
   return function(styles, result) {

lib/resolve-id.js

@@ -41,7 +41,12 @@ module.exports = function(id, base, options) {
     paths: paths,
     extensions: [ ".css" ],
     packageFilter: function processPackage(pkg) {
-      pkg.main = pkg.style || "index.css"
+      if (pkg.style) {
+        pkg.main = pkg.style
+      }
+      else if (!pkg.main || !/\.css$/.test(pkg.main)) {
+        pkg.main = "index.css"
+      }
       return pkg
     },
   }

test/fixtures/imports/modules/empty/index.css

@@ -0,0 +1 @@
+empty {}

test/fixtures/imports/modules/empty/package.json

@@ -0,0 +1 @@
+{}

test/fixtures/imports/modules/main-js/index.css

@@ -0,0 +1 @@
+main-js {}

test/fixtures/imports/modules/main-js/main.js

@@ -0,0 +1 @@
+module.exports = {}

test/fixtures/imports/modules/main-js/package.json

@@ -0,0 +1,3 @@
+{
+  "main": "main.js"
+}

test/fixtures/imports/modules/main-style/main.css

@@ -0,0 +1 @@
+style-mained {}

test/fixtures/imports/modules/main-style/package.json

@@ -0,0 +1,4 @@
+{
+  "main": "main.css",
+  "style": "style.css"
+}