csv: yield to block on each cell

Closes #151

Related to #145

docs/dsl/csv.rst

@@ -44,6 +44,19 @@ col_sep
 CSV custom options in Ruby standard lib.
   All of the options in Ruby's std lib version of CSV are supported **except** ``headers`` is always ``true`` and ``converters`` is always set to ``:numeric``. See the `Ruby Docs <http://ruby-doc.org/stdlib-2.2.0/libdoc/csv/rdoc/CSV.html#method-c-new>`_ for information on the options.
 
+Individual Pre-processing
+-------------------------
+
+The ``xlsx`` method also takes in a block that will be executed for each cell in your data. This is useful for processing individual cells, like putting a dollar sign in front of dollars, or converting from a float to an integer. The value of the block will be what is assigned to that cell. For example::
+
+  resource_data = Squib.csv(file: 'sample.xlsx') do |header, value|
+    case header
+    when 'Cost'
+      "$#{value}k" # e.g. "3" becomes "$3k"
+    else
+      value # always return the original value if you didn't do anything to it
+    end
+  end
 
 Examples
 --------

docs/dsl/xlsx.rst

@@ -9,7 +9,6 @@ The ``xlsx`` method is a member of ``Squib::Deck``, but it is also available out
   Squib::Deck.new(cards: data['name'].size) do
   end
 
-
 Options
 -------
 
@@ -33,5 +32,19 @@ explode
 
   Quantity explosion will be applied to the column this name. For example, rows in the csv with a ``'qty'`` of 3 will be duplicated 3 times.
 
+Individual Pre-processing
+-------------------------
+
+The ``xlsx`` method also takes in a block that will be executed for each cell in your data. This is useful for processing individual cells, like putting a dollar sign in front of dollars, or converting from a float to an integer. The value of the block will be what is assigned to that cell. For example::
+
+  resource_data = Squib.xlsx(file: 'sample.xlsx') do |header, value|
+    case header
+    when 'Cost'
+      "$#{value}k" # e.g. "3" becomes "$3k"
+    else
+      value # always return the original value if you didn't do anything to it
+    end
+  end
+
 Examples
 --------

lib/squib/api/data.rb

@@ -32,6 +32,7 @@ module Squib
 
   # DSL method. See http://squib.readthedocs.org
   def csv(opts = {})
+    # TODO refactor all this out to separate methods, and its own class
     import = Args::Import.new.load!(opts)
     file = Args::InputFile.new(file: 'deck.csv').load!(opts).file[0]
     data = opts.key?(:data) ? opts[:data] : File.read(file)
@@ -47,10 +48,20 @@ module Squib
     if import.strip?
       new_hash = Hash.new
       hash.each do |header, col|
-        new_hash[header] = col.map { |str| str = str.strip if str.respond_to?(:strip); str }
+        new_hash[header] = col.map do |str|
+          str = str.strip if str.respond_to?(:strip)
+          str
+        end
       end
       hash = new_hash
     end
+    if block_given?
+      hash.each do |header, col|
+        col.map! do |val|
+          yield(header, val)
+        end
+      end
+    end
     return explode_quantities(hash, import.explode)
   end
   module_function :csv

spec/api/api_data_spec.rb

@@ -76,6 +76,35 @@ describe Squib::Deck do
         })
     end
 
+    it 'yields to block when given' do
+      data = Squib.csv(file: csv_file('basic.csv')) do |header, value|
+        case header
+        when 'h1'
+          value * 2
+        else
+          'ha'
+        end
+      end
+      expect(data).to eq({
+        'h1' => [2, 6],
+        'h2' => %w(ha ha),
+        })
+    end
+
+    it 'replaces newlines whenever its a string' do
+      data = Squib.csv(file: csv_file('yield.csv')) do |header, value|
+        if value.respond_to? :gsub
+          value.gsub '%n', "\n"
+        else
+          value
+        end
+      end
+      expect(data).to eq({
+        'a' => ["foo\nbar", 1],
+        'b' => [1, "blah\n"],
+        })
+    end
+
   end
 
   context '#xlsx' do

spec/data/csv/yield.csv

@@ -0,0 +1,3 @@
+a,b
+foo%nbar,1
+1,blah%n