custom resolve function option

Author: zoubin

README.md

@@ -121,6 +121,13 @@ Default: `false`
 
 Set to `true` if you want @import rules to parse glob patterns.
 
+#### `resolve`
+
+Type: `Function`  
+Default: `null`
+
+You can overwrite the default path resolving way by setting this option, using the `resolve.sync(id, opts)` signature that [resolve.sync](https://github.com/substack/node-resolve#resolvesyncid-opts) has.
+
 #### Example with some options
 
 ```js

index.js

@@ -194,7 +194,7 @@ function readAtImport(atRule, options, cb, importedFiles, ignoredAtRules, media,
   }
 
   addInputToPath(options)
-  var resolvedFilename = resolveFilename(parsedAtImport.uri, options.root, options.path, atRule.source)
+  var resolvedFilename = resolveFilename(parsedAtImport.uri, options.root, options.path, atRule.source, options.resolve)
 
   // skip files already imported at the same scope
   if (importedFiles[resolvedFilename] && importedFiles[resolvedFilename][media]) {
@@ -336,7 +336,7 @@ function parseImport(str, source) {
  *
  * @param {String} name
  */
-function resolveFilename(name, root, paths, source) {
+function resolveFilename(name, root, paths, source, resolver) {
   var dir = source && source.input && source.input.file ? path.dirname(path.resolve(root, source.input.file)) : root
 
   try {
@@ -351,15 +351,16 @@ function resolveFilename(name, root, paths, source) {
       }
     }
     var file
+    resolver = resolver || resolve.sync;
     try {
-      file = resolve.sync(name, resolveOpts)
+      file = resolver(name, resolveOpts)
     }
     catch (e) {
       // fix to try relative files on windows with "./"
       // if it's look like it doesn't start with a relative path already
       // if (name.match(/^\.\.?/)) {throw e}
       try {
-        file = resolve.sync("./" + name, resolveOpts)
+        file = resolver("./" + name, resolveOpts)
       }
       catch (e) {
         // LAST HOPE

test/fixtures/custom-resolve-modules.css

@@ -0,0 +1,3 @@
+@import "sass-module";
+
+content{}

test/fixtures/custom-resolve-modules.expected.css

@@ -0,0 +1,3 @@
+.sass-module{}
+
+content{}

test/fixtures/imports/sass-module/main.scss

@@ -0,0 +1 @@
+.sass-module{}

test/fixtures/imports/sass-module/package.json

@@ -0,0 +1,2 @@
+{"sass": "main"}
+

test/index.js

@@ -190,3 +190,19 @@ test("works with no styles at all", function(t) {
 
   t.end()
 })
+
+test("@import custom resolve", function(t) {
+  var resolve = require("resolve")
+  var sassResolve = function(file, opts) {
+    opts = opts || {}
+    opts.extensions = [".scss", ".css"]
+    opts.packageFilter = function(pkg) {
+      pkg.main = pkg.sass || pkg.style || "index"
+      return pkg
+    }
+    return resolve.sync(file, opts)
+  }
+  compareFixtures(t, "custom-resolve-modules", "should be able to consume modules in the custom-resolve way", {root: __dirname, path: importsDir, resolve: sassResolve})
+
+  t.end()
+})