Merge pull request #2 from victormier/update-pr

Build command array one value at a time

Author: Andreas Rubik

lib/grim.rb

@@ -16,9 +16,6 @@ module Grim
 
   # Default colorspace
   COLORSPACE = "RGB"
-  
-  #Default Alpha
-  ALPHA = ""
 
   # Default exception class for Grim.
   class Exception < ::StandardError

lib/grim/image_magick_processor.rb

@@ -9,7 +9,7 @@ class ImageMagickProcessor
     def initialize(options={})
       @imagemagick_path = options[:imagemagick_path] || DefaultImagemagickPath
       @ghostscript_path = options[:ghostscript_path] || DefaultGhostScriptPath
-      @original_path        = ENV['PATH']
+      @original_path    = ENV['PATH']
     end
 
     def count(path)
@@ -21,16 +21,30 @@ def count(path)
     end
 
     def save(pdf, index, path, options)
-      width   = options.fetch(:width,   Grim::WIDTH)
-      density = options.fetch(:density, Grim::DENSITY)
-      quality = options.fetch(:quality, Grim::QUALITY)
+      width      = options.fetch(:width,   Grim::WIDTH)
+      density    = options.fetch(:density, Grim::DENSITY)
+      quality    = options.fetch(:quality, Grim::QUALITY)
       colorspace = options.fetch(:colorspace, Grim::COLORSPACE)
-      alpha   = options.fetch(:alpha, Grim::ALPHA)
-      alpha   = alpha == '' ? alpha : "-alpha #{alpha}"
-      command = [@imagemagick_path, "-resize", width.to_s, alpha, "-antialias", "-render",
-        "-quality", quality.to_s, "-colorspace", colorspace,
-        "-interlace", "none", "-density", density.to_s,
-        "#{Shellwords.shellescape(pdf.path)}[#{index}]", path]
+      alpha      = options[:alpha]
+
+      command = []
+      command << @imagemagick_path
+      command << "-resize"
+      command << width.to_s
+      command << "-alpha #{alpha}" if alpha
+      command << "-antialias"
+      command << "-render"
+      command << "-quality"
+      command << quality.to_s
+      command << "-colorspace"
+      command << colorspace
+      command << "-interlace"
+      command << "none"
+      command << "-density"
+      command << density.to_s
+      command << "#{Shellwords.shellescape(pdf.path)}[#{index}]"
+      command << path
+
       command.unshift("PATH=#{File.dirname(@ghostscript_path)}:#{ENV['PATH']}") if @ghostscript_path && @ghostscript_path != DefaultGhostScriptPath
 
       result = `#{command.join(' ')}`

spec/lib/grim_spec.rb

@@ -25,10 +25,6 @@
   it "should have COLORSPACE constant set to 'RGB'" do
     expect(Grim::COLORSPACE).to eq('RGB')
   end
-  
-  it "should have ALPHA constant set to 'Set'" do
-    expect(Grim::ALPHA).to eq('')
-  end
 
   describe "#reap" do
     it "should return an instance of Grim::Pdf" do