Module: Minitest::HashDiff

Defined in:
lib/minitest/hashdiff.rb,
lib/minitest/hashdiff/version.rb

Overview

Formats the difference between two hashes as a readable, sorted, type-aware report instead of two walls of inspect output.

Constant Summary collapse

VERSION = 
"0.1.1"

Class Method Summary collapse

Class Method Details

.display_type(value) ⇒ Object 



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# File 'lib/minitest/hashdiff.rb', line 13

def display_type(value)
  case value
  when nil then "nil"
  when true, false then "Boolean"
  when Integer then "Integer"
  when Float then "Float"
  when String then "String"
  when Symbol then "Symbol"
  when Hash then "Hash"
  when Array then "Array"
  else value.class.name
  end
end

.format(expected, actual) ⇒ Object

Returns a readable diff report, or nil when nothing differs.



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# File 'lib/minitest/hashdiff.rb', line 28

def format(expected, actual)
  lines = []
  walk(expected, actual, nil, lines)
  return nil if lines.empty?

  "Hash diff (expected => actual):\n#{lines.join("\n")}"
end

.walk(expected, actual, path, lines) ⇒ Object 



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# File 'lib/minitest/hashdiff.rb', line 36

def walk(expected, actual, path, lines)
  if expected.is_a?(Hash) && actual.is_a?(Hash)
    keys = (expected.keys | actual.keys).sort_by(&:inspect)
    keys.each do |key|
      key_path = path ? "#{path} > #{key.inspect}" : key.inspect
      if !expected.key?(key)
        lines << "  added   #{key_path}: #{actual[key].inspect}"
      elsif !actual.key?(key)
        lines << "  removed #{key_path}: #{expected[key].inspect}"
      elsif expected[key] != actual[key]
        walk(expected[key], actual[key], key_path, lines)
      end
    end
  elsif expected.is_a?(Array) && actual.is_a?(Array)
    [expected.size, actual.size].max.times do |i|
      item_path = "#{path}[#{i}]"
      if i >= expected.size
        lines << "  added   #{item_path}: #{actual[i].inspect}"
      elsif i >= actual.size
        lines << "  removed #{item_path}: #{expected[i].inspect}"
      elsif expected[i] != actual[i]
        walk(expected[i], actual[i], item_path, lines)
      end
    end
  else
    expected_type = display_type(expected)
    actual_type = display_type(actual)
    note = expected_type == actual_type ? "" : " (#{expected_type} -> #{actual_type})"
    lines << "  changed #{path}: #{expected.inspect} => #{actual.inspect}#{note}"
  end
end