Fresh work on nowrap cells

Based almost entirely on:

prawnpdf#50

Implements the wrapping, adds no more failures (than the current master fails on 3.0.4 anyway), but adds new tests and documentation.

Author: andyjeffries

lib/prawn/table/cell/text.rb

@@ -17,7 +17,7 @@ class Text < Cell
 
         TextOptions = [:inline_format, :kerning, :size, :align, :valign,
           :rotate, :rotate_around, :leading, :single_line, :skip_encoding,
-          :overflow, :min_font_size]
+          :overflow, :min_font_size, :nowrap]
 
         TextOptions.each do |option|
           define_method("#{option}=") { |v| @text_options[option] = v }
@@ -80,7 +80,7 @@ def set_width_constraints
           # sure we have enough width to be at least one character wide. This is
           # a bit of a hack, but it should work well enough.
           unless defined?(@min_width) && @min_width
-            min_content_width = [natural_content_width, styled_width_of_single_character].min
+            min_content_width = nowrap ? natural_content_width : [natural_content_width, styled_width_of_single_character].min
             @min_width = padding_left + padding_right + min_content_width
             super
           end
@@ -135,7 +135,15 @@ def text_box(extra_options={})
         #
         def styled_width_of(text)
           options = @text_options.reject { |k| k == :style }
-          with_font { @pdf.width_of(text, options) }
+
+          with_font do
+            @pdf.width_of(text, options)
+            if text.empty?
+              0
+            else
+              text.lines.map { |line| @pdf.width_of(line, options) }.max
+            end
+          end
         end
 
         private

manual/table/nowrap.rb

@@ -0,0 +1,18 @@
+# encoding: utf-8
+#
+# Columns specified as nowrap will always fit on to one line forcing others to
+# resize as appropriate.
+#
+require File.expand_path(File.join(File.dirname(__FILE__),
+                                   %w[.. example_helper]))
+
+filename = File.basename(__FILE__).gsub('.rb', '.pdf')
+Prawn::ManualBuilder::Example.generate(filename) do
+  text "Normal widths:"
+  table([["Blah " * 10, "Blah " * 10]])
+  move_down 20
+
+  text "Nowrap widths:"
+  table([[cell(:content => "Blah " * 10, :nowrap => true), "Blah " * 10]])
+  move_down 20
+end

manual/table/table.rb

@@ -24,6 +24,7 @@
       s.example "cell_borders_and_bg"
       s.example "cell_border_lines"
       s.example "cell_text"
+      s.example "nowrap"
       s.example "image_cells"
       s.example "span"
       s.example "before_rendering_page"

spec/cell_spec.rb

@@ -154,6 +154,21 @@ def cell(options={})
         (5 * @pdf.height_of("text"))
     end
 
+    it "should have a width that can fit @content without wrapping" do
+      c = cell(:content => "text", :padding => 10, :nowrap => true)
+      min_content_width = c.min_width - c.padding[1] - c.padding[3]
+
+      expect(@pdf.height_of("text", :width => min_content_width)).to eq(@pdf.height_of("text"))
+    end
+
+    it "should have a width that can fit @content without wrapping even if it's multiline" do
+      c = cell(:content => "text\nlonger", :padding => 10, :nowrap => true)
+      min_content_width = c.min_width - c.padding[1] - c.padding[3]
+
+      expect(@pdf.height_of("text\nlonger", :width => min_content_width)).to be <
+        (3 * @pdf.height_of("text"))
+    end
+
     it "should defer min_width's evaluation of padding" do
       c = cell(:content => "text", :padding => 100)
       c.padding = 0