brew/Library/Homebrew/test/test_compiler_selector.rb

require 'testing_env'
require 'compilers'
require 'software_spec'

class CompilerSelectorTests < Homebrew::TestCase
  class Double < SoftwareSpec
    def <<(cc)
      fails_with(cc)
      self
    end
  end

  class CompilerVersions
    attr_accessor :gcc_4_0_build_version, :gcc_build_version,
      :llvm_build_version, :clang_build_version

    def initialize(versions={})
      {
        :gcc_4_0_build_version => nil,
        :gcc_build_version     => 5666,
        :llvm_build_version    => 2336,
        :clang_build_version   => 425,
      }.merge(versions).each { |k, v| instance_variable_set("@#{k}", v) }
    end

    def non_apple_gcc_version(name)
      name == "gcc-4.8" ? "4.8.1" : nil
    end
  end

  def setup
    @f  = Double.new
    @cc = :clang
    @versions = CompilerVersions.new
  end

  def actual_cc
    CompilerSelector.new(@f, @versions).compiler
  end

  def test_all_compiler_failures
    @f << :clang << :llvm << :gcc << { :gcc => "4.8" }
    assert_raises(CompilerSelectionError) { actual_cc }
  end

  def test_no_compiler_failures
    assert_equal @cc, actual_cc
  end

  def test_fails_with_clang
    @f << :clang
    assert_equal :gcc, actual_cc
  end

  def test_fails_with_llvm
    @f << :llvm
    assert_equal :clang, actual_cc
  end

  def test_fails_with_gcc
    @f << :gcc
    assert_equal :clang, actual_cc
  end

  def test_fails_with_non_apple_gcc
    @f << { :gcc => "4.8" }
    assert_equal :clang, actual_cc
  end

  def test_mixed_failures_1
    @f << :clang << :llvm
    assert_equal :gcc, actual_cc
  end

  def test_mixed_failures_2
    @f << :gcc << :clang << { :gcc => "4.8" }
    assert_equal :llvm, actual_cc
  end

  def test_mixed_failures_3
    @f << :llvm << :gcc
    assert_equal :clang, actual_cc
  end

  def test_mixed_failures_4
    @f << :clang << { :gcc => "4.8" }
    assert_equal :gcc, actual_cc
  end

  def test_older_clang_precedence
    @versions.clang_build_version = 211
    @f << :gcc << { :gcc => "4.8" }
    assert_equal :llvm, actual_cc
  end

  def test_llvm_precedence
    @f << :clang << :gcc
    assert_equal :llvm, actual_cc
  end

  def test_missing_gcc
    @versions.gcc_build_version = nil
    @f << :clang << :llvm << { :gcc => "4.8" }
    assert_raises(CompilerSelectionError) { actual_cc }
  end

  def test_missing_llvm_and_gcc
    @versions.gcc_build_version = @versions.llvm_build_version = nil
    @f << :clang << { :gcc => "4.8" }
    assert_raises(CompilerSelectionError) { actual_cc }
  end
end