Recursion Exercises: Add total integers exercise

recursion/3_total_integers/.rspec

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+--require spec_helper --format documentation --color

recursion/3_total_integers/exercises/total_integers_exercises.rb

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+def total_integers(array)
+  # Count the total number of integers inside of the given array
+  # The array may be nested, and the integers inside these "inner" layers must also be counted
+  #
+  # Example: `total_integers([0, 1, [5]]) == 3`
+  #
+  # NOTE: you may notice that `Array#flatten` would make quick work of this,
+  # but you should implement this method without using it. The tests will check
+  # to make sure `#flatten` isn't used.
+end

recursion/3_total_integers/spec/spec_helper.rb

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+RSpec.configure do |config|
+  config.expect_with :rspec do |expectations|
+    expectations.include_chain_clauses_in_custom_matcher_descriptions = true
+  end
+
+  config.mock_with :rspec do |mocks|
+    mocks.verify_partial_doubles = true
+  end
+
+  config.shared_context_metadata_behavior = :apply_to_host_groups
+end
+
+module FormatterOverrides
+  def dump_pending(_)
+  end
+end
+
+RSpec::Core::Formatters::DocumentationFormatter.prepend FormatterOverrides

recursion/3_total_integers/spec/total_integers_exercises_spec.rb

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+require 'spec_helper'
+require_relative '../exercises/total_integers_exercises'
+
+RSpec.describe '#total_integers' do
+  it 'returns 3 with a 3 integer array' do
+    three_int_array = [1, 2, 3]
+    expect(total_integers(three_int_array)).to eq 3
+  end
+
+  xit 'ignores non integer values' do
+    array_with_string = [1, 2, '3']
+    expect(total_integers(array_with_string)).to eq 2
+  end
+
+  xit 'ignores floating point numbers' do
+    float_array = [1.0, 2.5, 0.7]
+    expect(total_integers(float_array)).to eq 0
+  end
+
+  xit 'returns 0 with an empty nested array' do
+    empty_nested_array = [[], [], []]
+    expect(total_integers(empty_nested_array)).to eq 0
+  end
+
+  xit 'returns 2 with a deeply nested two integer array' do
+    deeply_nested_array = [[[[[[[[[[[[[[4]]]]]], 246]]]]]]]]
+    expect(total_integers(deeply_nested_array)).to eq 2
+  end
+
+  xit 'returns 3 with a complex, deeply nested three integer array' do
+    complex_array = [{}, [555], '444', [nil, 74.0, [4]], [[6]]]
+    expect(total_integers(complex_array)).to eq 3
+  end
+
+  xit "does not call `Array#flatten`" do
+    three_int_array = [1, [2, 3]]
+    allow(three_int_array).to receive(:flatten).and_return [1, 2, 3]
+
+    total_integers(three_int_array)
+    expect(three_int_array).not_to have_received(:flatten)
+  end
+end

solutions/recursion/3_total_integers/.rspec

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+--require spec_helper --format documentation --color

solutions/recursion/3_total_integers/exercises/total_integers_exercises.rb

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+def total_integers(array)
+  array.sum do |element|
+    case element
+    when Integer
+      1
+    when Array
+      total_integers(element)
+    else
+      0
+    end
+  end
+end

solutions/recursion/3_total_integers/spec/spec_helper.rb

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+RSpec.configure do |config|
+  config.expect_with :rspec do |expectations|
+    expectations.include_chain_clauses_in_custom_matcher_descriptions = true
+  end
+
+  config.mock_with :rspec do |mocks|
+    mocks.verify_partial_doubles = true
+  end
+
+  config.shared_context_metadata_behavior = :apply_to_host_groups
+end
+
+module FormatterOverrides
+  def dump_pending(_)
+  end
+end
+
+RSpec::Core::Formatters::DocumentationFormatter.prepend FormatterOverrides

solutions/recursion/3_total_integers/spec/total_integers_exercises_spec.rb

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+require 'spec_helper'
+require_relative '../exercises/total_integers_exercises'
+
+RSpec.describe '#total_integers' do
+  it 'returns 3 with a 3 integer array' do
+    three_int_array = [1, 2, 3]
+    expect(total_integers(three_int_array)).to eq 3
+  end
+
+  it 'ignores non integer values' do
+    array_with_string = [1, 2, '3']
+    expect(total_integers(array_with_string)).to eq 2
+  end
+
+  it 'ignores floating point numbers' do
+    float_array = [1.0, 2.5, 0.7]
+    expect(total_integers(float_array)).to eq 0
+  end
+
+  it 'returns 0 with an empty nested array' do
+    empty_nested_array = [[], [], []]
+    expect(total_integers(empty_nested_array)).to eq 0
+  end
+
+  it 'returns 2 with a deeply nested two integer array' do
+    deeply_nested_array = [[[[[[[[[[[[[[4]]]]]], 246]]]]]]]]
+    expect(total_integers(deeply_nested_array)).to eq 2
+  end
+
+  it 'returns 3 with a complex, deeply nested three integer array' do
+    complex_array = [{}, [555], '444', [nil, 74.0, [4]], [[6]]]
+    expect(total_integers(complex_array)).to eq 3
+  end
+
+  it "does not call `Array#flatten`" do
+    three_int_array = [1, [2, 3]]
+    allow(three_int_array).to receive(:flatten).and_return [1, 2, 3]
+
+    total_integers(three_int_array)
+    expect(three_int_array).not_to have_received(:flatten)
+  end
+end