Add SpaceBetweenParens linter

README.md

@@ -387,6 +387,18 @@ Any lint can be disabled by using the `--exclude_linter` flag.
     color: rgba(0, 0, 0, .1);
     ```
 
+* Parentheses should not (or should) be padded with spaces.
+
+    ```scss
+    // Incorrect
+    @include box-shadow( 0 2px 2px rgba( 0, 0, 0, .2 ) );
+    color: rgba( 0, 0, 0, .1 );
+
+    // Correct
+    @include box-shadow(0 2px 2px rgba(0, 0, 0, .2));
+    color: rgba(0, 0, 0, .1);
+    ```
+
 * Properties should be formatted with no space between the name and the colon,
   and a single space separating the colon from the property's value.
 

config/default.yml

@@ -68,6 +68,10 @@ linters:
   SpaceBeforeBrace:
     enabled: true
 
+  SpaceBetweenParens:
+    enabled: true
+    spaces: 0
+
   TrailingSemicolonAfterPropertyValue:
     enabled: true
 

lib/scss_lint/linter/space_between_parens.rb

@@ -0,0 +1,26 @@
+module SCSSLint
+  # Checks for the presence of spaces between parentheses.
+  class Linter::SpaceBetweenParens < Linter
+    include LinterRegistry
+
+    def visit_root(node)
+      @spaces = config['spaces']
+      engine.lines.each_with_index do |line, index|
+        line.scan /(\( *[^ ]|[^ ] *\))/ do |match|
+          match.each { |str| check(str, index, engine) }
+        end
+      end
+    end
+
+  private
+
+    def check(str, index, engine)
+      spaces = str.count ' '
+
+      if spaces != @spaces
+        @lints << Lint.new(engine.filename, index + 1, "Expected #{pluralize(@spaces, 'space')}" <<
+                                                       " between parenthesis instead of #{spaces}")
+      end
+    end
+  end
+end

spec/scss_lint/linter/space_between_parens_spec.rb

@@ -0,0 +1,87 @@
+require 'spec_helper'
+
+describe SCSSLint::Linter::SpaceBetweenParens do
+  context 'when the opening parens is followed by a space' do
+    let(:css) { <<-CSS }
+      p {
+        property: ( value)
+      }
+    CSS
+
+    it { should report_lint line: 2 }
+  end
+
+  context 'when the closing parens is preceded by a space' do
+    let(:css) { <<-CSS }
+      p {
+        property: (value )
+      }
+    CSS
+
+    it { should report_lint line: 2 }
+  end
+
+  context 'when both parens are space padded' do
+    let(:css) { <<-CSS }
+      p {
+        property: ( value )
+      }
+    CSS
+
+    it { should report_lint line: 2, count: 2 }
+  end
+
+  context 'when neither parens are space padded' do
+    let(:css) { <<-CSS }
+      p {
+        property: (value)
+      }
+    CSS
+
+    it { should_not report_lint }
+  end
+
+  context 'when the number of spaces has been explicitly set' do
+    let(:linter_config) { { 'spaces' => 1 } }
+
+    context 'when the opening parens is followed by a space' do
+      let(:css) { <<-CSS }
+        p {
+          property: ( value)
+        }
+      CSS
+
+      it { should report_lint line: 2 }
+    end
+
+    context 'when the closing parens is preceded by a space' do
+      let(:css) { <<-CSS }
+        p {
+          property: (value )
+        }
+      CSS
+
+      it { should report_lint line: 2 }
+    end
+
+    context 'when both parens are space padded' do
+      let(:css) { <<-CSS }
+        p {
+          property: (value)
+        }
+      CSS
+
+      it { should report_lint line: 2, count: 2 }
+    end
+
+    context 'when neither parens are space padded' do
+      let(:css) { <<-CSS }
+        p {
+          property: ( value )
+        }
+      CSS
+
+      it { should_not report_lint }
+    end
+  end
+end