[Haml] Compatibility with the latest Rails 3 helper changes.

Closes gh-101

doc-src/HAML_CHANGELOG.md

@@ -15,6 +15,12 @@
 
 * Make the error message for `- end` a little more intuitive based on user feedback.
 
+* Compatibility with methods like `form_for`
+  that return strings rather than concatenate to the template in Rails 3.
+
+* Add a {Haml::Helpers#with_tabs with_tabs} helper,
+  which sets the indentation level for the duration of a block.
+
 ## 2.2.20
 
 [Tagged on GitHub](http://github.com/nex3/haml/commit/2.2.20).

lib/haml/helpers.rb

@@ -234,6 +234,33 @@ MESSAGE
       haml_buffer.tabulation -= i
     end
 
+    # Sets the number of tabs the buffer automatically adds
+    # to the lines of the template,
+    # but only for the duration of the block.
+    # For example:
+    #
+    #     %h1 foo
+    #     - with_tabs(2) do
+    #       %p bar
+    #     %strong baz
+    #
+    # Produces:
+    #
+    #     <h1>foo</h1>
+    #         <p>bar</p>
+    #     <strong>baz</strong>
+    #
+    #
+    # @param i [Fixnum] The number of tabs to use
+    # @yield [] A block in which the indentation will be `i` spaces
+    def with_tabs(i)
+      old_tabs = haml_buffer.tabulation
+      haml_buffer.tabulation = i
+      yield
+    ensure
+      haml_buffer.tabulation = old_tabs
+    end
+
     # Surrounds a block of Haml code with strings,
     # with no whitespace in between.
     # For example:

lib/haml/helpers/action_view_mods.rb

@@ -131,13 +131,74 @@ module ActionView
       end
     end
 
-    module FormTagHelper
-      def form_tag_with_haml(url_for_options = {}, options = {}, *parameters_for_url, &proc)
-        if is_haml?
-          if block_given?
+    if Haml::Util.ap_geq_3?
+      module FormTagHelper
+        def form_tag_with_haml(url_for_options = {}, options = {}, *parameters_for_url, &proc)
+          if is_haml?
+            if block_given?
+              oldproc = proc
+              proc = haml_bind_proc do |*args|
+                concat "\n"
+                with_tabs(1) {oldproc.call(*args)}
+              end
+            end
+            res = form_tag_without_haml(url_for_options, options, *parameters_for_url, &proc) + "\n"
+            res << "\n" if block_given?
+            res
+          else
+            form_tag_without_haml(url_for_options, options, *parameters_for_url, &proc)
+          end
+        end
+        alias_method :form_tag_without_haml, :form_tag
+        alias_method :form_tag, :form_tag_with_haml
+      end
+
+      module FormHelper
+        def form_for_with_haml(object_name, *args, &proc)
+          if block_given? && is_haml?
+            oldproc = proc
+            proc = haml_bind_proc do |*args|
+              with_tabs(1) {oldproc.call(*args)}
+            end
+          end
+          res = form_for_without_haml(object_name, *args, &proc)
+          res << "\n" if block_given? && is_haml?
+          res
+        end
+        alias_method :form_for_without_haml, :form_for
+        alias_method :form_for, :form_for_with_haml
+      end
+    else
+      module FormTagHelper
+        def form_tag_with_haml(url_for_options = {}, options = {}, *parameters_for_url, &proc)
+          if is_haml?
+            if block_given?
+              oldproc = proc
+              proc = haml_bind_proc do |*args|
+                concat "\n"
+                tab_up
+                oldproc.call(*args)
+                tab_down
+                concat haml_indent
+              end
+              concat haml_indent
+            end
+            res = form_tag_without_haml(url_for_options, options, *parameters_for_url, &proc) + "\n"
+            concat "\n" if block_given?
+            res
+          else
+            form_tag_without_haml(url_for_options, options, *parameters_for_url, &proc)
+          end
+        end
+        alias_method :form_tag_without_haml, :form_tag
+        alias_method :form_tag, :form_tag_with_haml
+      end
+
+      module FormHelper
+        def form_for_with_haml(object_name, *args, &proc)
+          if block_given? && is_haml?
             oldproc = proc
             proc = haml_bind_proc do |*args|
-              concat "\n"
               tab_up
               oldproc.call(*args)
               tab_down
@@ -145,34 +206,12 @@ module ActionView
             end
             concat haml_indent
           end
-          res = form_tag_without_haml(url_for_options, options, *parameters_for_url, &proc) + "\n"
-          concat "\n" if block_given?
-          res
-        else
-          form_tag_without_haml(url_for_options, options, *parameters_for_url, &proc)
+          form_for_without_haml(object_name, *args, &proc)
+          concat "\n" if block_given? && is_haml?
         end
+        alias_method :form_for_without_haml, :form_for
+        alias_method :form_for, :form_for_with_haml
       end
-      alias_method :form_tag_without_haml, :form_tag
-      alias_method :form_tag, :form_tag_with_haml
-    end
-
-    module FormHelper
-      def form_for_with_haml(object_name, *args, &proc)
-        if block_given? && is_haml?
-          oldproc = proc
-          proc = haml_bind_proc do |*args|
-            tab_up
-            oldproc.call(*args)
-            tab_down
-            concat haml_indent
-          end
-          concat haml_indent
-        end
-        form_for_without_haml(object_name, *args, &proc)
-        concat "\n" if block_given? && is_haml?
-      end
-      alias_method :form_for_without_haml, :form_for
-      alias_method :form_for, :form_for_with_haml
     end
   end
 end

lib/haml/helpers/xss_mods.rb

@@ -97,6 +97,14 @@ end
 
 module ActionView
   module Helpers
+    module CaptureHelper
+      def with_output_buffer_with_haml_xss(*args, &block)
+        Haml::Util.html_safe(with_output_buffer_without_haml_xss(*args, &block))
+      end
+      alias_method :with_output_buffer_without_haml_xss, :with_output_buffer
+      alias_method :with_output_buffer, :with_output_buffer_with_haml_xss
+    end
+
     module FormTagHelper
       def form_tag_with_haml_xss(*args, &block)
         Haml::Util.html_safe(form_tag_without_haml_xss(*args, &block))
@@ -105,6 +113,14 @@ module ActionView
       alias_method :form_tag, :form_tag_with_haml_xss
     end
 
+    module FormHelper
+      def form_for_with_haml_xss(*args, &block)
+        Haml::Util.html_safe(form_for_without_haml_xss(*args, &block))
+      end
+      alias_method :form_for_without_haml_xss, :form_for
+      alias_method :form_for, :form_for_with_haml_xss
+    end
+
     module TextHelper
       def concat_with_haml_xss(string)
         if is_haml?

lib/haml/util.rb

@@ -157,6 +157,31 @@ module Haml
       return nil
     end
 
+    # Returns whether this environment is using ActionPack
+    # version 3.0.0 or greater.
+    #
+    # @return [Boolean]
+    def ap_geq_3?
+      # The ActionPack module is always loaded automatically in Rails >= 3
+      return false unless defined?(ActionPack) && defined?(ActionPack::VERSION)
+
+      version =
+        if defined?(ActionPack::VERSION::MAJOR)
+          ActionPack::VERSION::MAJOR
+        else
+          # Rails 1.2
+          ActionPack::VERSION::Major
+        end
+
+      # 3.0.0.beta1 acts more like ActionPack 2
+      # for purposes of this method
+      # (checking whether block helpers require = or -).
+      # This extra check can be removed when beta2 is out.
+      version >= 3 &&
+        !(defined?(ActionPack::VERSION::TINY) &&
+          ActionPack::VERSION::TINY == "0.beta")
+    end
+
     # Returns an ActionView::Template* class.
     # In pre-3.0 versions of Rails, most of these classes
     # were of the form `ActionView::TemplateFoo`,

test/haml/helper_test.rb

@@ -65,7 +65,21 @@ class HelperTest < Test::Unit::TestCase
     assert_equal("foo\n  bar\nbaz\n", render("foo\n- tab_up\nbar\n- tab_down\nbaz"))
     assert_equal("          <p>tabbed</p>\n", render("- buffer.tabulation=5\n%p tabbed"))
   end
-  
+
+  def test_with_tabs
+    assert_equal(<<HTML, render(<<HAML))
+Foo
+    Bar
+    Baz
+Baz
+HTML
+Foo
+- with_tabs 2 do
+  = "Bar\\nBaz"
+Baz
+HAML
+  end
+
   def test_helpers_dont_leak
     # Haml helpers shouldn't be accessible from ERB
     render("foo")
@@ -93,9 +107,16 @@ class HelperTest < Test::Unit::TestCase
   def test_form_tag
     # This is usually provided by ActionController::Base.
     def @base.protect_against_forgery?; false; end
-    result = render("- form_tag 'foo' do\n  %p bar\n  %strong baz", :action_view)
-    should_be = "<form action=\"foo\" method=\"post\">\n  <p>bar</p>\n  <strong>baz</strong>\n</form>\n"
-    assert_equal(should_be, result)
+    assert_equal(<<HTML, render(<<HAML, :action_view))
+<form action="foo" method="post">
+  <p>bar</p>
+  <strong>baz</strong>
+</form>
+HTML
+#{rails_block_helper_char} form_tag 'foo' do
+  %p bar
+  %strong baz
+HAML
   end
 
   def test_text_area
@@ -114,12 +135,12 @@ class HelperTest < Test::Unit::TestCase
   end
 
   def test_content_tag_block
-    assert_equal(<<HTML.strip, render(<<HAML, :action_view))
+    assert_equal(<<HTML.strip, render(<<HAML, :action_view).strip)
 <div><p>bar</p>
 <strong>bar</strong>
 </div>
 HTML
-- content_tag :div do
+#{rails_block_helper_char} content_tag :div do
   %p bar
   %strong bar
 HAML

test/haml/template_test.rb

@@ -70,8 +70,9 @@ class TemplateTest < Test::Unit::TestCase
     end
     
     if Haml::Util.has?(:private_method, base, :evaluate_assigns)
+      # Rails < 3.0
       base.send(:evaluate_assigns)
-    else
+    elsif Haml::Util.has?(:private_method, base, :_evaluate_assigns_and_ivars)
       # Rails 2.2
       base.send(:_evaluate_assigns_and_ivars)
     end
@@ -338,7 +339,7 @@ HAML
   <input id="article_body" name="article[body]" size="30" type="text" value="World" />
 </form>
 HTML
-- form_for :article, @article, :url => '' do |f|
+#{rails_block_helper_char} form_for :article, @article, :url => '' do |f|
   Title:
   = f.text_field :title
   Body:

test/haml/templates/helpers.haml

@@ -62,6 +62,19 @@ click
         <input id="article_body" name="article[body]" size="30" type="text" value="World" />
       </form>
     </div>
+- elsif Haml::Util.ap_geq_3?
+  %p
+    = form_tag ''
+  %div
+    = form_tag '' do
+      %div= submit_tag 'save'
+      - @foo = 'value one'
+      = test_partial 'partial'
+    = form_for :article, @article, :url => '' do |f|
+      Title:
+      = f.text_field :title
+      Body:
+      = f.text_field :body
 - else
   %p
     = form_tag ''

test/test_helper.rb

@@ -32,4 +32,9 @@ class Test::Unit::TestCase
   def silence_warnings(&block)
     Haml::Util.silence_warnings(&block)
   end
+
+  def rails_block_helper_char
+    return '=' if Haml::Util.ap_geq_3?
+    return '-'
+  end
 end