From f140ff32fa25abc5924a8793c48d19dea2333ded Mon Sep 17 00:00:00 2001
From: Andy Meneely <andy@se.rit.edu>
Date: Sat, 15 Apr 2017 21:25:34 -0400
Subject: [PATCH] Cleanup and tests of yaml method

---
 CHANGELOG.md              |  3 +-
 docs/dsl/yaml.rst         | 73 +++++++++++++++++++++++++++++++++++++++
 lib/squib/api/data.rb     | 22 ++++++++----
 spec/api/api_data_spec.rb | 40 +++++++++++++++++++++
 spec/data/yaml/basic.yml  |  6 ++++
 spec/data/yaml/nilly.yml  |  3 ++
 spec/data/yaml/qty.yml    |  4 +++
 spec/spec_helper.rb       |  4 +++
 8 files changed, 147 insertions(+), 8 deletions(-)
 create mode 100644 docs/dsl/yaml.rst
 create mode 100644 spec/data/yaml/basic.yml
 create mode 100644 spec/data/yaml/nilly.yml
 create mode 100644 spec/data/yaml/qty.yml

diff --git a/CHANGELOG.md b/CHANGELOG.md
index f729c3c..b6ba38a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,8 +6,9 @@ Squib follows [semantic versioning](http://semver.org).
 Features:
 * `circle` method now supports various `arc` options, so you can draw partial circles (#211) by @sparr
 * `save_sheet` method now supports `rtl` or "right-to-left", for easier duplex printing of backs (#204, #208) by @sparr
+* `yaml` method for reading in data, much like `csv` and `xlsx` by @blinks
 
-Special thanks to @sparr for all of his work!!
+Special thanks to @sparr and @blinks for all of their work!!
 
 ## v0.13.2 / 2017-01-27
 
diff --git a/docs/dsl/yaml.rst b/docs/dsl/yaml.rst
new file mode 100644
index 0000000..52381ba
--- /dev/null
+++ b/docs/dsl/yaml.rst
@@ -0,0 +1,73 @@
+yaml
+====
+
+Pulls deck data from a YAML files into a ``Squib::DataFrame`` (essentially a hash of arrays).
+
+Parsing uses Ruby's built-in Yaml package.
+
+The ``yaml`` method is a member of ``Squib::Deck``, but it is also available outside of the Deck DSL with ``Squib.yaml()``. This allows a construction like::
+
+  data = Squib.Yaml file: 'data.yml'
+    Squib::Deck.new(cards: data['name'].size) do
+  end
+
+The Yaml file format assumes that the entire deck is an array, then each element of the array is a hash. Every key encountered in that hash will translate to a "column" in the data frame. If a key exists in one card and not in another, then it defaults to ``nil``.
+
+.. warning::
+
+  Case matters in your Yaml keys.
+
+Options
+-------
+
+file
+  default: ``'deck.yml'``
+
+  the YAML-formatted file to open. Opens relative to the current directory. If ``data`` is set, this option is overridden.
+
+data
+  default: ``nil``
+
+  when set, method will parse this Yaml data instead of reading the file.
+
+explode
+  default: ``'qty'``
+
+  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 ``yaml`` 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.yaml(file: 'sample.yaml') 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
+--------
+
+
+To get the sample Excel files, go to `its source <https://github.com/andymeneely/squib/tree/dev/samples/data>`_
+
+.. literalinclude:: ../../samples/data/_csv.rb
+  :language: ruby
+  :linenos:
+
+Here's the sample.csv
+
+.. literalinclude:: ../../samples/data/sample.csv
+  :language: text
+  :linenos:
+
+Here's the quantity_explosion.csv
+
+.. literalinclude:: ../../samples/data/quantity_explosion.csv
+  :language: text
+  :linenos:
diff --git a/lib/squib/api/data.rb b/lib/squib/api/data.rb
index f142027..a834c98 100644
--- a/lib/squib/api/data.rb
+++ b/lib/squib/api/data.rb
@@ -67,19 +67,27 @@ module Squib
     return explode_quantities(hash, import.explode)
   end
   module_function :csv
-  
+
   # DSL method. See http://squib.readthedocs.io
   def yaml(opts = {})
     input = Args::InputFile.new(file: 'deck.yml').load!(opts)
     import = Args::Import.new.load!(opts)
-    s = YAML.load_file(input.file[0])
+    yml = YAML.load_file(input.file[0])
     data = Squib::DataFrame.new
     # Get a universal list of keys to ensure everything is covered.
-    keys = s.map {|c| c.keys}.flatten.uniq
-    # Initialize the data frame; why is [] not the default value?
-    keys.each {|k| data[k] = [] }
-    # Load all cards into the frame, nil value if key isn't set.
-    s.each {|card| keys.each {|k| data[k] << card[k] } }
+    keys = yml.map { |c| c.keys}.flatten.uniq
+    keys.each { |k| data[k] = [] } #init arrays
+    yml.each do |card|
+      # nil value if key isn't set.
+      keys.each { |k| data[k] << card[k] }
+    end
+    if block_given?
+      data.each do |header, col|
+        col.map! do |val|
+          yield(header, val)
+        end
+      end
+    end
     explode_quantities(data, import.explode)
   end
   module_function :yaml
diff --git a/spec/api/api_data_spec.rb b/spec/api/api_data_spec.rb
index 4993eb9..074482e 100644
--- a/spec/api/api_data_spec.rb
+++ b/spec/api/api_data_spec.rb
@@ -169,4 +169,44 @@ describe Squib::Deck do
     end
 
   end
+
+  context '#yaml' do
+    it 'loads basic data' do
+      expect(Squib.yaml(file: yaml_file('basic.yml')).to_h).to eq({
+        'Name'           => %w(Larry Curly Mo),
+        'Number' => [4.0, 5.0, 6.0], # numbers get auto-converted to integers
+        })
+    end
+
+    it 'explodes quantities' do
+     expect(Squib.yaml(explode: 'qty', file: yaml_file('qty.yml')).to_h).to eq({
+        'name' => %w(ha ha he),
+        'qty'  => [2, 2, 1],
+        })
+    end
+
+    it 'handles silence' do
+     expect(Squib.yaml(file: yaml_file('nilly.yml')).to_h).to eq({
+        'name' => %w(foo bar),
+        'desc'  => [nil, 'Hello'],
+        })
+    end
+
+    it 'yields to block when given' do
+      data = Squib.yaml(file: yaml_file('basic.yml')) do |header, value|
+        case header
+        when 'Name'
+          'he'
+        when 'Number'
+          value * 2
+        else
+          'ha'
+        end
+      end
+      expect(data.to_h).to eq({
+        'Name'   => %w(he he he),
+        'Number' => [8.0, 10.0, 12.0],
+        })
+    end
+  end
 end
diff --git a/spec/data/yaml/basic.yml b/spec/data/yaml/basic.yml
new file mode 100644
index 0000000..a23f26a
--- /dev/null
+++ b/spec/data/yaml/basic.yml
@@ -0,0 +1,6 @@
+- Name: Larry
+  Number: 4.0
+- Name: Curly
+  Number: 5.0
+- Name: Mo
+  Number: 6.0
diff --git a/spec/data/yaml/nilly.yml b/spec/data/yaml/nilly.yml
new file mode 100644
index 0000000..e7ac7ca
--- /dev/null
+++ b/spec/data/yaml/nilly.yml
@@ -0,0 +1,3 @@
+- name: foo
+- name: bar
+  desc: Hello
diff --git a/spec/data/yaml/qty.yml b/spec/data/yaml/qty.yml
new file mode 100644
index 0000000..6eeb25a
--- /dev/null
+++ b/spec/data/yaml/qty.yml
@@ -0,0 +1,4 @@
+- name: ha
+  qty: 2
+- name: he
+  qty: 1
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 8c69de9..cd9e39b 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -46,6 +46,10 @@ def xlsx_file(file)
   "#{File.expand_path(File.dirname(__FILE__))}/data/xlsx/#{file}"
 end
 
+def yaml_file(file)
+  "#{File.expand_path(File.dirname(__FILE__))}/data/yaml/#{file}"
+end
+
 def project_template(file)
   "#{File.expand_path(File.dirname(__FILE__))}/../lib/squib/project_template/#{file}"
 end