Merge pull request #795 from prawnpdf/rtl_indent_paragraphs

Indent right side on RTL text

lib/prawn/text.rb

@@ -116,7 +116,7 @@ module Text
     #                   the current font familly. [current style]
     # <tt>:indent_paragraphs</tt>:: <tt>number</tt>. The amount to indent the
     #                               first line of each paragraph. Omit this
-    #                               option if you do not want indenting
+    #                               option if you do not want indenting.
     # <tt>:direction</tt>::
     #     <tt>:ltr</tt>, <tt>:rtl</tt>, Direction of the text (left-to-right
     #     or right-to-left) [value of document.text_direction]
@@ -359,7 +359,10 @@ def draw_remaining_formatted_text_on_new_pages(remaining_text, options)
     end
 
     def draw_indented_formatted_line(string, options)
-      indent(@indent_paragraphs) do
+      gap = options.fetch(:direction, :ltr) == :ltr ?
+              [@indent_paragraphs, 0] : [0, @indent_paragraphs]
+
+      indent(*gap) do
         fill_formatted_text_box(string, options.dup.merge(:single_line => true))
       end
     end

manual/text/paragraph_indentation.rb

@@ -23,4 +23,12 @@
   text "This paragraph will be indented. " * 10 +
        "\n" + "This one will too. " * 10,
        :indent_paragraphs => 60
+
+  move_down 20
+
+  text "FROM RIGHT TO LEFT:"
+  text "This paragraph will be indented. " * 10 +
+        "\n" + "This one will too. " * 10,
+        :indent_paragraphs => 60, :direction => :rtl
+
 end

prawn.gemspec

@@ -27,7 +27,7 @@ Gem::Specification.new do |spec|
   spec.add_dependency('ttfunk', '~> 1.4.0')
   spec.add_dependency('pdf-core', "~> 0.5.0")
 
-  spec.add_development_dependency('pdf-inspector', '~> 1.1.0')
+  spec.add_development_dependency('pdf-inspector', '~> 1.2.0')
   spec.add_development_dependency('yard')
   spec.add_development_dependency('rspec', '2.14.1')
   spec.add_development_dependency('mocha')

spec/text_spec.rb

@@ -350,6 +350,57 @@
       text.strings[3].should == ("hello " * 19).strip
       text.strings[4].should == ("hello " * 21).strip
     end
+
+
+    it "should indent from right side when using :rtl direction" do
+      para1 = "The rain in spain falls mainly on the plains " * 3
+      para2 = "The rain in spain falls mainly on the plains " * 3
+
+      @pdf.text(para1 + "\n" + para2, :indent_paragraphs => 60, :direction => :rtl)
+
+      text = PDF::Inspector::Text.analyze(@pdf.render)
+
+      lines = text.strings
+      x_positions = text.positions.map { |e| e[0] }
+
+      # NOTE: The code below reflects Prawn's current kerning behavior for RTL
+      # text, which isn't necessarily correct. If we change that behavior,
+      # this test will need to be updated.
+
+      x_positions[0].should(
+        be_within(0.001).of(@pdf.bounds.absolute_right - 60 -
+                            @pdf.width_of(lines[0].reverse, :kerning => true)))
+
+      x_positions[1].should(
+        be_within(0.001).of(@pdf.bounds.absolute_right -
+                            @pdf.width_of(lines[1].reverse, :kerning => true)))
+
+      x_positions[2].should(
+        be_within(0.001).of(@pdf.bounds.absolute_right - 60 -
+                            @pdf.width_of(lines[2].reverse, :kerning => true)))
+
+      x_positions[3].should(
+        be_within(0.001).of(@pdf.bounds.absolute_right -
+                            @pdf.width_of(lines[3].reverse, :kerning => true)))
+    end
+
+    it "should indent from right side when using :ltr direction" do
+      para1 = "The rain in spain falls mainly on the plains " * 3
+      para2 = "The rain in spain falls mainly on the plains " * 3
+
+      @pdf.text(para1 + "\n" + para2, :indent_paragraphs => 60, :direction => :ltr)
+
+      text = PDF::Inspector::Text.analyze(@pdf.render)
+
+      x_positions = text.positions.map { |e| e[0] }
+
+      x_positions[0].should == 60
+      x_positions[1].should == 0
+
+      x_positions[2].should == 60
+      x_positions[3].should == 0
+    end
+
     describe "when wrap to new page, and first line of new page" +
              " is not the start of a new paragraph, that line should" +
              " not be indented" do