etl: added generator

exercises/etl/.meta/.version

@@ -0,0 +1 @@
+1

exercises/etl/etl_test.rb

@@ -1,58 +1,113 @@
-#!/usr/bin/env ruby
-gem 'minitest', '>= 5.0.0'
 require 'minitest/autorun'
 require_relative 'etl'
 
-class TransformTest < Minitest::Test
-  def test_transform_one_value
-    old = { 1 => ['A'] }
-    expected = { 'a' => 1 }
+# Test data version: 040a24f
+class EtlTest < Minitest::Test
+  def test_a_single_letter
+    # skip
+    old = {
+       '1' => ["A"],
+    }
+    expected = {
+       'a' => '1',
+    }
 
     assert_equal expected, ETL.transform(old)
   end
 
-  def test_transform_more_values
+  def test_single_score_with_multiple_letters
     skip
-    old = { 1 => %w(A E I O U) }
-    expected = { 'a' => 1, 'e' => 1, 'i' => 1, 'o' => 1, 'u' => 1 }
+    old = {
+       '1' => ["A", "E", "I", "O", "U"],
+    }
+    expected = {
+       'a' => '1',
+       'e' => '1',
+       'i' => '1',
+       'o' => '1',
+       'u' => '1',
+    }
 
     assert_equal expected, ETL.transform(old)
   end
 
-  def test_more_keys
+  def test_multiple_scores_with_multiple_letters
     skip
-    old = { 1 => %w(A E), 2 => %w(D G) }
+    old = {
+       '1' => ["A", "E"],
+       '2' => ["D", "G"],
+    }
     expected = {
-      'a' => 1,
-      'e' => 1,
-      'd' => 2,
-      'g' => 2
+       'a' => '1',
+       'e' => '1',
+       'd' => '2',
+       'g' => '2',
     }
 
     assert_equal expected, ETL.transform(old)
   end
 
-  def test_full_dataset
+  def test_multiple_scores_with_differing_numbers_of_letters
     skip
     old = {
-      1 => %w(A E I O U L N R S T),
-      2 => %w(D G),
-      3 => %w(B C M P),
-      4 => %w(F H V W Y),
-      5 => %w(K),
-      8 => %w(J X),
-      10 => %w(Q Z)
+       '1' => ["A", "E", "I", "O", "U", "L", "N", "R", "S", "T"],
+       '2' => ["D", "G"],
+       '3' => ["B", "C", "M", "P"],
+       '4' => ["F", "H", "V", "W", "Y"],
+       '5' => ["K"],
+       '8' => ["J", "X"],
+       '10' => ["Q", "Z"],
     }
-
     expected = {
-      'a' => 1, 'b' => 3, 'c' => 3, 'd' => 2, 'e' => 1,
-      'f' => 4, 'g' => 2, 'h' => 4, 'i' => 1, 'j' => 8,
-      'k' => 5, 'l' => 1, 'm' => 3, 'n' => 1, 'o' => 1,
-      'p' => 3, 'q' => 10, 'r' => 1, 's' => 1, 't' => 1,
-      'u' => 1, 'v' => 4, 'w' => 4, 'x' => 8, 'y' => 4,
-      'z' => 10
+       'a' => '1',
+       'b' => '3',
+       'c' => '3',
+       'd' => '2',
+       'e' => '1',
+       'f' => '4',
+       'g' => '2',
+       'h' => '4',
+       'i' => '1',
+       'j' => '8',
+       'k' => '5',
+       'l' => '1',
+       'm' => '3',
+       'n' => '1',
+       'o' => '1',
+       'p' => '3',
+       'q' => '10',
+       'r' => '1',
+       's' => '1',
+       't' => '1',
+       'u' => '1',
+       'v' => '4',
+       'w' => '4',
+       'x' => '8',
+       'y' => '4',
+       'z' => '10',
     }
 
     assert_equal expected, ETL.transform(old)
   end
+
+  # Problems in exercism evolve over time, as we find better ways to ask
+  # questions.
+  # The version number refers to the version of the problem you solved,
+  # not your solution.
+  #
+  # Define a constant named VERSION inside of the top level BookKeeping
+  # module, which may be placed near the end of your file.
+  #
+  # In your file, it will look like this:
+  #
+  # module BookKeeping
+  #   VERSION = 1 # Where the version number matches the one in the test.
+  # end
+  #
+  # If you are curious, read more about constants on RubyDoc:
+  # http://ruby-doc.org/docs/ruby-doc-bundle/UsersGuide/rg/constants.html
+  def test_bookkeeping
+    skip
+    assert_equal 1, BookKeeping::VERSION
+  end
 end

exercises/etl/example.rb

@@ -1,3 +1,7 @@
+module BookKeeping
+  VERSION = 1
+end
+
 class ETL
   def self.transform(old)
     data = {}

exercises/etl/example.tt

@@ -0,0 +1,17 @@
+require 'minitest/autorun'
+require_relative 'etl'
+
+# Test data version: <%= abbreviated_commit_hash %>
+class EtlTest < Minitest::Test<% test_cases.each do |test_case| %>
+  def <%= test_case.test_name %>
+    <%= test_case.skipped %>
+    <%= test_case.workload %>
+  end
+<% end %>
+
+<%= IO.read(XRUBY_LIB + '/bookkeeping.md') %>
+  def test_bookkeeping
+    skip
+    assert_equal <%= version.next %>, BookKeeping::VERSION
+  end
+end

lib/etl_cases.rb

@@ -0,0 +1,48 @@
+require 'exercise_cases'
+
+class EtlCase < OpenStruct
+  def test_name
+    'test_%s' % description.tr(' ,-', '_').downcase
+  end
+
+  def workload
+    [
+      "old = #{format_hash(integerize_keys(input))}",
+      "    expected = #{format_hash(expected)}\n",
+      indent(4, assertion),
+    ].join("\n")
+  end
+
+  def skipped
+    index.zero? ? '# skip' : 'skip'
+  end
+
+  private
+
+  def indent(size, text)
+    text.lines.each_with_object('') { |line, obj| obj << ' ' * size + line }
+  end
+
+  def assertion
+    "assert_equal expected, ETL.transform(old)"
+  end
+
+  def integerize_keys(input)
+    input.reduce({}) { |hash, (k, v)| hash[k.to_i] = v; hash }
+  end
+
+  def format_hash(hash)
+    middle = hash.each_pair.with_object('') do |(k, v), obj|
+      value = v.class == Array ? v : "'#{v}'"
+      obj << "      '#{k}' => #{value},\n "
+    end
+    "{\n #{middle}   }"
+  end
+
+end
+
+EtlCases = proc do |data|
+  JSON.parse(data)['transform']['cases'].map.with_index do |row, i|
+    EtlCase.new(row.merge(index: i))
+  end
+end