Ignore dynamic falsy attributes

Fixes haml#2.
k0kubun · Apr 12, 2015 · 8700951 · 8700951
1 parent bc20a93
commit 8700951
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Showing 2 changed files with 80 additions and 14 deletions.
diff --git a/lib/hamlit/compilers/old_attribute.rb b/lib/hamlit/compilers/old_attribute.rb
@@ -15,14 +15,27 @@ module OldAttribute
       include Concerns::Balanceable
       include Concerns::Ripperable
 
-      # For performance, only data can be nested.
+      # Only data can be nested for performance.
       NESTABLE_ATTRIBUTES = %w[data].freeze
       IGNORED_EXPRESSIONS = %w[false nil].freeze
 
+      # Only boolean attributes can be deleted for performance.
+      BOOLEAN_ATTRIBUTES  = %w[
+        autofocus
+        checked
+        data
+        disabled
+        formnovalidate
+        multiple
+        readonly
+      ].freeze
+
       def compile_old_attribute(str)
         raise RuntimeBuild unless Ripper.sexp(str)
 
         attrs = parse_old_attributes(str)
+        assert_no_boolean_attributes!(attrs)
+
         format_attributes(attrs).map do |key, value|
           next true_attribute(key) if value == 'true'
           assert_static_value!(value) if NESTABLE_ATTRIBUTES.include?(key)
@@ -56,6 +69,14 @@ def assert_static_value!(value)
         end
       end
 
+      # Give up static compilation when attributes have deletable
+      # attributes, such as 'checked'.
+      def assert_no_boolean_attributes!(attrs)
+        if BOOLEAN_ATTRIBUTES.any? { |key| attrs.keys.include?(key) }
+          raise RuntimeBuild
+        end
+      end
+
       # Parse brace-balanced string and return the result as hash
       def parse_old_attributes(str)
         attributes = {}

diff --git a/spec/hamlit/engine/old_attributes_spec.rb b/spec/hamlit/engine/old_attributes_spec.rb
@@ -40,19 +40,6 @@
       HTML
     end
 
-    it 'renders false or nil attributes' do
-      assert_render(<<-'HAML', <<-HTML)
-        - hash = { checked: false }
-        %input{ hash }
-        %input{ checked: false }
-        %input{ checked: nil }
-      HAML
-        <input>
-        <input>
-        <input>
-      HTML
-    end
-
     it 'accepts even illegal input for haml' do
       assert_render(<<-'HAML', <<-HTML)
         %span{ class: '}}}', id: '{}}' } }{
@@ -86,6 +73,64 @@
       HTML
     end
 
+    describe 'deletable attributes' do
+      it 'deletes attributes whose value is nil or false' do
+        assert_render(<<-'HAML', <<-HTML)
+          - hash = { checked: false }
+          %input{ hash }
+          %input{ checked: false }
+          %input{ checked: nil }
+          - checked = nil
+          %input{ checked: checked }
+          - checked = false
+          %input{ checked: checked }
+        HAML
+          <input>
+          <input>
+          <input>
+          <input>
+          <input>
+        HTML
+      end
+
+      it 'deletes some limited attributes with dynamic value' do
+        assert_render(<<-'HAML', <<-HTML)
+          - val = false
+          #foo.bar{ autofocus: val }
+          #foo.bar{ checked: val }
+          #foo.bar{ data: { disabled: val } }
+          #foo.bar{ disabled: val }
+          #foo.bar{ formnovalidate: val }
+          #foo.bar{ multiple: val }
+          #foo.bar{ readonly: val }
+        HAML
+          <div class='bar' id='foo'></div>
+          <div class='bar' id='foo'></div>
+          <div class='bar' id='foo'></div>
+          <div class='bar' id='foo'></div>
+          <div class='bar' id='foo'></div>
+          <div class='bar' id='foo'></div>
+          <div class='bar' id='foo'></div>
+        HTML
+      end
+
+      it 'does not delete some attributes, for optimization' do
+        assert_render(<<-'HAML', <<-HTML)
+          - val = false
+          %a{ href: val }
+          %a{ class: val }
+          - val = nil
+          %a{ href: val }
+          %a{ class: val }
+        HAML
+          <a href='false'></a>
+          <a class='false'></a>
+          <a href=''></a>
+          <a class=''></a>
+        HTML
+      end
+    end
+
     describe 'html escape' do
       it 'escapes attribute values on static attributes' do
         assert_render(<<-'HAML', <<-HTML)