literal_in_interpolation_spec.rb

# frozen_string_literal: true

RSpec.describe RuboCop::Cop::Lint::LiteralInInterpolation do
  subject(:cop) { described_class.new }

  it 'accepts empty interpolation' do
    expect_no_offenses('"this is #{a} silly"')
  end

  it 'accepts interpolation of xstr' do
    expect_no_offenses('"this is #{`a`} silly"')
  end

  it 'accepts interpolation of irange where endpoints are not literals' do
    expect_no_offenses('"this is an irange: #{var1..var2}"')
  end

  it 'accepts interpolation of erange where endpoints are not literals' do
    expect_no_offenses('"this is an erange: #{var1...var2}"')
  end

  shared_examples 'literal interpolation' do |literal, expected = literal|
    it "registers an offense for #{literal} in interpolation" do
      inspect_source(%("this is the \#{#{literal}}"))
      expect(cop.offenses.size).to eq(1)
    end

    it "should have #{literal} as the message highlight" do
      inspect_source(%("this is the \#{#{literal}}"))
      expect(cop.highlights).to eq([literal.to_s])
    end

    it "removes interpolation around #{literal}" do
      corrected = autocorrect_source(%("this is the \#{#{literal}}"))
      expect(corrected).to eq(%("this is the #{expected}"))
    end

    it "removes interpolation around #{literal} when there is more text" do
      corrected =
        autocorrect_source(%("this is the \#{#{literal}} literally"))
      expect(corrected).to eq(%("this is the #{expected} literally"))
    end

    it "removes interpolation around multiple #{literal}" do
      corrected =
        autocorrect_source(%("some \#{#{literal}} with \#{#{literal}} too"))
      expect(corrected).to eq(%("some #{expected} with #{expected} too"))
    end

    context 'when there is non-literal and literal interpolation' do
      context 'when literal interpolation is before non-literal' do
        it 'only remove interpolation around literal' do
          corrected =
            autocorrect_source(%("this is \#{#{literal}} with \#{a} now"))
          expect(corrected).to eq(%("this is #{expected} with \#{a} now"))
        end
      end

      context 'when literal interpolation is after non-literal' do
        it 'only remove interpolation around literal' do
          corrected =
            autocorrect_source(%("this is \#{a} with \#{#{literal}} now"))
          expect(corrected).to eq(%("this is \#{a} with #{expected} now"))
        end
      end
    end

    it "registers an offense only for final #{literal} in interpolation" do
      inspect_source(%("this is the \#{#{literal};#{literal}}"))
      expect(cop.offenses.size).to eq(1)
    end
  end

  it_behaves_like('literal interpolation', 1)
  it_behaves_like('literal interpolation', -1)
  it_behaves_like('literal interpolation', '1_123', '1123')
  it_behaves_like('literal interpolation',
                  '123_456_789_123_456_789', '123456789123456789')
  it_behaves_like('literal interpolation', '1.2e-3', '0.0012')
  it_behaves_like('literal interpolation', '0xaabb', '43707')
  it_behaves_like('literal interpolation', '0o377', '255')
  it_behaves_like('literal interpolation', 2.0)
  it_behaves_like('literal interpolation', '[]', '[]')
  it_behaves_like('literal interpolation', '["a", "b"]', '[\"a\", \"b\"]')
  it_behaves_like('literal interpolation', '{"a" => "b"}', '{\"a\" => \"b\"}')
  it_behaves_like('literal interpolation', true)
  it_behaves_like('literal interpolation', false)
  it_behaves_like('literal interpolation', 'nil')
  it_behaves_like('literal interpolation', ':symbol', 'symbol')
  it_behaves_like('literal interpolation', ':"symbol"', 'symbol')
  it_behaves_like('literal interpolation', 1..2)
  it_behaves_like('literal interpolation', 1...2)
  it_behaves_like('literal interpolation', '%w[]', '[]')
  it_behaves_like('literal interpolation', '%w[v1]', '[\"v1\"]')
  it_behaves_like('literal interpolation', '%w[v1 v2]', '[\"v1\", \"v2\"]')
  it_behaves_like('literal interpolation', '%i[s1 s2]', '[\"s1\", \"s2\"]')
  it_behaves_like('literal interpolation', '%I[s1 s2]', '[\"s1\", \"s2\"]')
  it_behaves_like('literal interpolation', '%i[s1     s2]', '[\"s1\", \"s2\"]')
  it_behaves_like('literal interpolation', '%i[ s1   s2 ]', '[\"s1\", \"s2\"]')

  it 'handles nested interpolations when auto-correction' do
    corrected = autocorrect_source(%("this is \#{"\#{1}"} silly"))
    # next iteration fixes this
    expect(corrected).to eq %("this is \#{"1"} silly")
  end

  shared_examples 'special keywords' do |keyword|
    it "accepts strings like #{keyword}" do
      expect_no_offenses(<<-RUBY.strip_indent)
        %("this is \#{#{keyword}} silly")
      RUBY
    end

    it "does not try to autocorrect strings like #{keyword}" do
      corrected = autocorrect_source(%("this is the \#{#{keyword}} silly"))

      expect(corrected).to eq(%("this is the \#{#{keyword}} silly"))
    end

    it "registers an offense for interpolation after #{keyword}" do
      inspect_source(%("this is the \#{#{keyword}} \#{1}"))
      expect(cop.offenses.size).to eq(1)
    end

    it "auto-corrects literal interpolation after #{keyword}" do
      corrected = autocorrect_source(%("this is the \#{#{keyword}} \#{1}"))
      expect(corrected).to eq(%("this is the \#{#{keyword}} 1"))
    end
  end

  it_behaves_like('special keywords', '__FILE__')
  it_behaves_like('special keywords', '__LINE__')
  it_behaves_like('special keywords', '__RUBY__')
  it_behaves_like('special keywords', '__ENCODING__')

  shared_examples 'non-special string literal interpolation' do |string|
    it "registers an offense for #{string}" do
      inspect_source(%("this is the \#{#{string}}"))
      expect(cop.offenses.size).to eq(1)
    end

    it "should have #{string} in the message highlight" do
      inspect_source(%("this is the \#{#{string}}"))
      expect(cop.highlights).to eq([string])
    end

    it "should remove the interpolation and quotes around #{string}" do
      corrected = autocorrect_source(%("this is the \#{#{string}}"))
      expect(corrected).to eq(%("this is the #{string.gsub(/'|"/, '')}"))
    end
  end

  it_behaves_like('non-special string literal interpolation', %('foo'))
  it_behaves_like('non-special string literal interpolation', %("foo"))

  it 'handles double quotes in single quotes when auto-correction' do
    corrected = autocorrect_source(<<-'RUBY'.strip_indent)
      "this is #{'"'} silly"
    RUBY
    expect(corrected).to eq(<<-'RUBY'.strip_indent)
      "this is \" silly"
    RUBY
  end

  it 'handles backslach in single quotes when auto-correction' do
    corrected = autocorrect_source(<<-'RUBY'.strip_indent)
      x = "ABC".gsub(/(A)(B)(C)/, "D#{'\2'}F")
      "this is #{'\n'} silly"
      "this is #{%q(\n)} silly"
    RUBY
    expect(corrected).to eq(<<-'RUBY'.strip_indent)
      x = "ABC".gsub(/(A)(B)(C)/, "D\\2F")
      "this is \\n silly"
      "this is \\n silly"
    RUBY
  end

  it 'handles backslach in double quotes when auto-correction' do
    corrected = autocorrect_source(<<-'RUBY'.strip_indent)
      "this is #{"\n"} silly"
      "this is #{%(\n)} silly"
      "this is #{%Q(\n)} silly"
    RUBY
    expect(corrected).to eq(<<-'RUBY'.strip_indent)
      "this is 
       silly"
      "this is 
       silly"
      "this is 
       silly"
    RUBY
  end
end