Allow setting of SASS_BINARY_DIR without setting explicit binary name

lib/extensions.js

@@ -7,7 +7,7 @@ var eol = require('os').EOL,
   pkg = require('../package.json'),
   mkdir = require('mkdirp'),
   path = require('path'),
-  defaultBinaryPath = path.join(__dirname, '..', 'vendor'),
+  defaultBinaryDir = path.join(__dirname, '..', 'vendor'),
   trueCasePathSync = require('true-case-path');
 
 /**
@@ -126,7 +126,7 @@ function getHumanEnvironment(env) {
  * @api public
  */
 function getInstalledBinaries() {
-  return fs.readdirSync(defaultBinaryPath);
+  return fs.readdirSync(getBinaryDir());
 }
 
 /**
@@ -246,6 +246,38 @@ function getBinaryUrl() {
 }
 
 /**
+ * Get binary dir.
+ * If environment variable SASS_BINARY_DIR,
+ * .npmrc variable sass_binary_dir or
+ * process argument --sass-binary-dir is provided,
+ * select it by appending binary name, otherwise
+ * use default binary dir.
+ * Once the primary selection is made, check if
+ * callers wants to throw if file not exists before
+ * returning.
+ *
+ * @api public
+ */
+
+function getBinaryDir() {
+  var binaryDir;
+
+  if (getArgument('--sass-binary-dir')) {
+    binaryDir = getArgument('--sass-binary-dir');
+  } else if (process.env.SASS_BINARY_DIR) {
+    binaryDir = process.env.SASS_BINARY_DIR;
+  } else if (process.env.npm_config_sass_binary_dir) {
+    binaryDir = process.env.npm_config_sass_binary_dir;
+  } else if (pkg.nodeSassConfig && pkg.nodeSassConfig.binaryDir) {
+    binaryDir = pkg.nodeSassConfig.binaryDir;
+  } else {
+    binaryDir = defaultBinaryDir;
+  }
+
+  return binaryDir;
+}
+
+/**
  * Get binary path.
  * If environment variable SASS_BINARY_PATH,
  * .npmrc variable sass_binary_path or
@@ -271,7 +303,7 @@ function getBinaryPath() {
   } else if (pkg.nodeSassConfig && pkg.nodeSassConfig.binaryPath) {
     binaryPath = pkg.nodeSassConfig.binaryPath;
   } else {
-    binaryPath = path.join(defaultBinaryPath, getBinaryName().replace(/_(?=binding\.node)/, '/'));
+    binaryPath = path.join(getBinaryDir(), getBinaryName().replace(/_(?=binding\.node)/, '/'));
   }
 
   if (process.versions.modules < 46) {
@@ -415,6 +447,7 @@ function getPlatformVariant() {
 module.exports.hasBinary = hasBinary;
 module.exports.getBinaryUrl = getBinaryUrl;
 module.exports.getBinaryName = getBinaryName;
+module.exports.getBinaryDir = getBinaryDir;
 module.exports.getBinaryPath = getBinaryPath;
 module.exports.getBinaryCachePath = getBinaryCachePath;
 module.exports.getCachedBinary = getCachedBinary;

test/runtime.js

@@ -83,6 +83,37 @@ describe('runtime parameters', function() {
       });
     });
 
+    describe('SASS_BINARY_DIR', function() {
+      beforeEach(function() {
+        process.argv.push('--sass-binary-dir', 'aaa');
+        process.env.SASS_BINARY_DIR = 'bbb';
+        process.env.npm_config_sass_binary_dir = 'ccc';
+        pkg.nodeSassConfig = { binaryDir: 'ddd' };
+      });
+
+      it('command line argument', function() {
+        assert.equal(sass.getBinaryDir(), 'aaa');
+      });
+
+      it('environment variable', function() {
+        process.argv = [];
+        assert.equal(sass.getBinaryDir(), 'bbb');
+      });
+
+      it('npm config variable', function() {
+        process.argv = [];
+        process.env.SASS_BINARY_DIR = null;
+        assert.equal(sass.getBinaryDir(), 'ccc');
+      });
+
+      it('package.json', function() {
+        process.argv = [];
+        process.env.SASS_BINARY_DIR = null;
+        process.env.npm_config_sass_binary_dir = null;
+        assert.equal(sass.getBinaryDir(), 'ddd');
+      });
+    });
+
     describe('SASS_BINARY_PATH', function() {
       beforeEach(function() {
         process.argv.push('--sass-binary-path', 'aaa_binding.node');