Class: MiniTest::Unit::TestCase

Inherits:
Object
  • Object
show all
Extended by:
Guard
Includes:
Assertions, Guard
Defined in:
lib/minitest/unit.rb,
lib/minitest/benchmark.rb

Overview

Subclass TestCase to create your own tests. Typically you’ll want a TestCase subclass per implementation class.

See MiniTest::Assertions

Direct Known Subclasses

Spec

Constant Summary collapse

PASSTHROUGH_EXCEPTIONS = 
[NoMemoryError, SignalException,
Interrupt, SystemExit]
SUPPORTS_INFO_SIGNAL =

:nodoc:


      
    

  



  
  
  
Constants included
     from Assertions

  
Assertions::UNDEFINED, Assertions::WINDOZE



  
Instance Attribute Summary collapse

  




  
    

      Class Method Summary
      collapse
    


    
  
    

      Instance Method Summary
      collapse
    


    
  


  
  
  
  
  
  
  
  
  
Methods included from Guard

  
jruby?, mri?, rubinius?, windows?


  
  
  
  
  
  
  
  
  
Methods included from Assertions

  
#_assertions, #_assertions=, #assert, #assert_block, #assert_empty, #assert_equal, #assert_in_delta, #assert_in_epsilon, #assert_includes, #assert_instance_of, #assert_kind_of, #assert_match, #assert_nil, #assert_operator, #assert_output, #assert_predicate, #assert_raises, #assert_respond_to, #assert_same, #assert_send, #assert_silent, #assert_throws, #capture_io, #diff, diff, diff=, #exception_details, #flunk, #message, #mu_pp, #mu_pp_for_diff, #pass, #refute, #refute_empty, #refute_equal, #refute_in_delta, #refute_in_epsilon, #refute_includes, #refute_instance_of, #refute_kind_of, #refute_match, #refute_nil, #refute_operator, #refute_predicate, #refute_respond_to, #refute_same, #skip


  

  
Constructor Details

  
    

  

  
    #initialize(name)  ⇒ TestCase 
  

  

  




  

    

:nodoc:



  





  



  

    
      


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# File 'lib/minitest/unit.rb', line 1096

def initialize name # :nodoc:
  @__name__ = name
  @__io__ = nil
  @passed = nil
  @@current = self
end

    		
  





  



  

    
Instance Attribute Details

    
      
      
      

  

  
    #__name__  ⇒ Object  (readonly)
  

  

  




  

    

:nodoc:



  





  



  

    
      


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# File 'lib/minitest/unit.rb', line 1044

def __name__
  @__name__
end

    		
  





    
  



  

    
Class Method Details


    
      

  

  
    .add_setup_hook(arg = nil, &block)  ⇒ Object 
  

  

  




  

    

Adds a block of code that will be executed before every TestCase is run. Equivalent to setup, but usable multiple times and without re-opening any classes.



All of the setup hooks will run in order after the setup method, if one is defined.



The argument can be any object that responds to #call or a block. That means that this call,



MiniTest::Unit::TestCase.add_setup_hook { puts "foo" }




… is equivalent to:



module MyTestSetup
  def self.call
    puts "foo"
  end
end

MiniTest::Unit::TestCase.add_setup_hook MyTestSetup




The blocks passed to add_setup_hook take an optional parameter that will be the TestCase instance that is executing the block.



  





  



  

    
      


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# File 'lib/minitest/unit.rb', line 1240

def self.add_setup_hook arg=nil, &block
  hook = arg || block
  @setup_hooks << hook
end

    		
  





    
      

  

  
    .add_teardown_hook(arg = nil, &block)  ⇒ Object 
  

  

  




  

    

Adds a block of code that will be executed after every TestCase is run. Equivalent to teardown, but usable multiple times and without re-opening any classes.



All of the teardown hooks will run in reverse order after the teardown method, if one is defined.



The argument can be any object that responds to #call or a block. That means that this call,



MiniTest::Unit::TestCase.add_teardown_hook { puts "foo" }




… is equivalent to:



module MyTestTeardown
  def self.call
    puts "foo"
  end
end

MiniTest::Unit::TestCase.add_teardown_hook MyTestTeardown




The blocks passed to add_teardown_hook take an optional parameter that will be the TestCase instance that is executing the block.



  





  



  

    
      


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# File 'lib/minitest/unit.rb', line 1289

def self.add_teardown_hook arg=nil, &block
  hook = arg || block
  @teardown_hooks << hook
end

    		
  





    
      

  

  
    .bench_exp(min, max, base = 10)  ⇒ Object 
  

  

  




  

    

Returns a set of ranges stepped exponentially from min to max by powers of base. Eg:



bench_exp(2, 16, 2) # => [2, 4, 8, 16]




  





  



  

    
      


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# File 'lib/minitest/benchmark.rb', line 20

def self.bench_exp min, max, base = 10
  min = (Math.log10(min) / Math.log10(base)).to_i
  max = (Math.log10(max) / Math.log10(base)).to_i

  (min..max).map { |m| base ** m }.to_a
end

    		
  





    
      

  

  
    .bench_linear(min, max, step = 10)  ⇒ Object 
  

  

  




  

    

Returns a set of ranges stepped linearly from min to max by step. Eg:



bench_linear(20, 40, 10) # => [20, 30, 40]




  





  



  

    
      


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# File 'lib/minitest/benchmark.rb', line 33

def self.bench_linear min, max, step = 10
  (min..max).step(step).to_a
rescue LocalJumpError # 1.8.6
  r = []; (min..max).step(step) { |n| r << n }; r
end

    		
  





    
      

  

  
    .bench_range  ⇒ Object 
  

  

  




  

    

Specifies the ranges used for benchmarking for that class. Defaults to exponential growth from 1 to 10k by powers of 10. Override if you need different ranges for your benchmarks.



See also: ::bench_exp and ::bench_linear.



  





  



  

    
      


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# File 'lib/minitest/benchmark.rb', line 61

def self.bench_range
  bench_exp 1, 10_000
end

    		
  





    
      

  

  
    .benchmark_methods  ⇒ Object 
  

  

  




  

    

Returns the benchmark methods (methods that start with bench_) for that class.



  





  



  

    
      


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# File 'lib/minitest/benchmark.rb', line 43

def self.benchmark_methods # :nodoc:
  public_instance_methods(true).grep(/^bench_/).map { |m| m.to_s }.sort
end

    		
  





    
      

  

  
    .benchmark_suites  ⇒ Object 
  

  

  




  

    

Returns all test suites that have benchmark methods.



  





  



  

    
      


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# File 'lib/minitest/benchmark.rb', line 50

def self.benchmark_suites
  TestCase.test_suites.reject { |s| s.benchmark_methods.empty? }
end

    		
  





    
      

  

  
    .current  ⇒ Object 
  

  

  




  

    

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# File 'lib/minitest/unit.rb', line 1103

def self.current # :nodoc:
  @@current
end

    		
  





    
      

  

  
    .i_suck_and_my_tests_are_order_dependent!  ⇒ Object 
  

  

  




  

    

Call this at the top of your tests when you absolutely positively need to have ordered tests. In doing so, you’re admitting that you suck and your tests are weak.



  





  



  

    
      


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# File 'lib/minitest/unit.rb', line 1133

def self.i_suck_and_my_tests_are_order_dependent!
  class << self
    undef_method :test_order if method_defined? :test_order
    define_method :test_order do :alpha end
  end
end

    		
  





    
      

  

  
    .inherited(klass)  ⇒ Object 
  

  

  




  

    

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# File 'lib/minitest/unit.rb', line 1140

def self.inherited klass # :nodoc:
  @@test_suites[klass] = true
  klass.reset_setup_teardown_hooks
  super
end

    		
  





    
      

  

  
    .reset  ⇒ Object 
  

  

  




  

    

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# File 'lib/minitest/unit.rb', line 1122

def self.reset # :nodoc:
  @@test_suites = {}
end

    		
  





    
      

  

  
    .reset_setup_teardown_hooks  ⇒ Object 
  

  

  




  

    

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# File 'lib/minitest/unit.rb', line 1207

def self.reset_setup_teardown_hooks # :nodoc:
  @setup_hooks = []
  @teardown_hooks = []
end

    		
  





    
      

  

  
    .setup_hooks  ⇒ Object 
  

  

  




  

    

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# File 'lib/minitest/unit.rb', line 1245

def self.setup_hooks # :nodoc:
  if superclass.respond_to? :setup_hooks then
    superclass.setup_hooks
  else
    []
  end + @setup_hooks
end

    		
  





    
      

  

  
    .teardown_hooks  ⇒ Object 
  

  

  




  

    

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# File 'lib/minitest/unit.rb', line 1294

def self.teardown_hooks # :nodoc:
  if superclass.respond_to? :teardown_hooks then
    superclass.teardown_hooks
  else
    []
  end + @teardown_hooks
end

    		
  





    
      

  

  
    .test_methods  ⇒ Object 
  

  

  




  

    

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# File 'lib/minitest/unit.rb', line 1154

def self.test_methods # :nodoc:
  methods = public_instance_methods(true).grep(/^test/).map { |m| m.to_s }

  case self.test_order
  when :random then
    max = methods.size
    methods.sort.sort_by { rand max }
  when :alpha, :sorted then
    methods.sort
  else
    raise "Unknown test_order: #{self.test_order.inspect}"
  end
end

    		
  





    
      

  

  
    .test_order  ⇒ Object 
  

  

  




  

    

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# File 'lib/minitest/unit.rb', line 1146

def self.test_order # :nodoc:
  :random
end

    		
  





    
      

  

  
    .test_suites  ⇒ Object 
  

  

  




  

    

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# File 'lib/minitest/unit.rb', line 1150

def self.test_suites # :nodoc:
  @@test_suites.keys.sort_by { |ts| ts.name.to_s }
end

    		
  





    
  


  

    
Instance Method Details


    
      

  

  
    #after_setup  ⇒ Object 
  

  

  




  

    

Runs before every test after setup. Use this to refactor test initialization.



  





  



  

    
      


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# File 'lib/minitest/unit.rb', line 1184

def after_setup; end

    		
  





    
      

  

  
    #after_teardown  ⇒ Object 
  

  

  




  

    

Runs after every teardown. Use this to refactor test cleanup.



  





  



  

    
      


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# File 'lib/minitest/unit.rb', line 1205

def after_teardown; end

    		
  





    
      

  

  
    #assert_performance(validation, &work)  ⇒ Object 
  

  

  




  

    

Runs the given work, gathering the times of each run. Range and times are then passed to a given validation proc. Outputs the benchmark name and times in tab-separated format, making it easy to paste into a spreadsheet for graphing or further analysis.



Ranges are specified by ::bench_range.



Eg:



def bench_algorithm
  validation = proc { |x, y| ... }
  assert_performance validation do |n|
    @obj.algorithm(n)
  end
end




  





  



  

    
      


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# File 'lib/minitest/benchmark.rb', line 83

def assert_performance validation, &work
  range = self.class.bench_range

  io.print "#{__name__}"

  times = []

  range.each do |x|
    GC.start
    t0 = Time.now
    instance_exec(x, &work)
    t = Time.now - t0

    io.print "\t%9.6f" % t
    times << t
  end
  io.puts

  validation[range, times]
end

    		
  





    
      

  

  
    #assert_performance_constant(threshold = 0.99, &work)  ⇒ Object 
  

  

  




  

    

Runs the given work and asserts that the times gathered fit to match a constant rate (eg, linear slope == 0) within a given threshold. Note: because we’re testing for a slope of 0, R^2 is not a good determining factor for the fit, so the threshold is applied against the slope itself. As such, you probably want to tighten it from the default.



See www.graphpad.com/curvefit/goodness_of_fit.htm for more details.



Fit is calculated by #fit_linear.



Ranges are specified by ::bench_range.



Eg:



def bench_algorithm
  assert_performance_constant 0.9999 do |n|
    @obj.algorithm(n)
  end
end




  





  



  

    
      


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# File 'lib/minitest/benchmark.rb', line 127

def assert_performance_constant threshold = 0.99, &work
  validation = proc do |range, times|
    a, b, rr = fit_linear range, times
    assert_in_delta 0, b, 1 - threshold
    [a, b, rr]
  end

  assert_performance validation, &work
end

    		
  





    
      

  

  
    #assert_performance_exponential(threshold = 0.99, &work)  ⇒ Object 
  

  

  




  

    

Runs the given work and asserts that the times gathered fit to match a exponential curve within a given error threshold.



Fit is calculated by #fit_exponential.



Ranges are specified by ::bench_range.



Eg:



def bench_algorithm
  assert_performance_exponential 0.9999 do |n|
    @obj.algorithm(n)
  end
end




  





  



  

    
      


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# File 'lib/minitest/benchmark.rb', line 153

def assert_performance_exponential threshold = 0.99, &work
  assert_performance validation_for_fit(:exponential, threshold), &work
end

    		
  





    
      

  

  
    #assert_performance_linear(threshold = 0.99, &work)  ⇒ Object 
  

  

  




  

    

Runs the given work and asserts that the times gathered fit to match a straight line within a given error threshold.



Fit is calculated by #fit_linear.



Ranges are specified by ::bench_range.



Eg:



def bench_algorithm
  assert_performance_linear 0.9999 do |n|
    @obj.algorithm(n)
  end
end




  





  



  

    
      


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# File 'lib/minitest/benchmark.rb', line 173

def assert_performance_linear threshold = 0.99, &work
  assert_performance validation_for_fit(:linear, threshold), &work
end

    		
  





    
      

  

  
    #assert_performance_power(threshold = 0.99, &work)  ⇒ Object 
  

  

  




  

    

Runs the given work and asserts that the times gathered curve fit to match a power curve within a given error threshold.



Fit is calculated by #fit_power.



Ranges are specified by ::bench_range.



Eg:



def bench_algorithm
  assert_performance_power 0.9999 do |x|
    @obj.algorithm
  end
end




  





  



  

    
      


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# File 'lib/minitest/benchmark.rb', line 193

def assert_performance_power threshold = 0.99, &work
  assert_performance validation_for_fit(:power, threshold), &work
end

    		
  





    
      

  

  
    #before_setup  ⇒ Object 
  

  

  




  

    

Runs before every setup. Use this to refactor test initialization.



  





  



  

    
      


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# File 'lib/minitest/unit.rb', line 1189

def before_setup; end

    		
  





    
      

  

  
    #before_teardown  ⇒ Object 
  

  

  




  

    

Runs after every test before teardown. Use this to refactor test initialization.



  





  



  

    
      


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# File 'lib/minitest/unit.rb', line 1200

def before_teardown; end

    		
  





    
      

  

  
    #fit_error(xys)  ⇒ Object 
  

  

  




  

    

Takes an array of x/y pairs and calculates the general R^2 value.



See: en.wikipedia.org/wiki/Coefficient_of_determination



  





  



  

    
      


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# File 'lib/minitest/benchmark.rb', line 202

def fit_error xys
  y_bar  = sigma(xys) { |x, y| y } / xys.size.to_f
  ss_tot = sigma(xys) { |x, y| (y    - y_bar) ** 2 }
  ss_err = sigma(xys) { |x, y| (yield(x) - y) ** 2 }

  1 - (ss_err / ss_tot)
end

    		
  





    
      

  

  
    #fit_exponential(xs, ys)  ⇒ Object 
  

  

  




  

    

To fit a functional form: y = ae^(bx).



Takes x and y values and returns [a, b, r^2].



See: mathworld.wolfram.com/LeastSquaresFittingExponential.html



  





  



  

    
      


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# File 'lib/minitest/benchmark.rb', line 217

def fit_exponential xs, ys
  n     = xs.size
  xys   = xs.zip(ys)
  sxlny = sigma(xys) { |x,y| x * Math.log(y) }
  slny  = sigma(xys) { |x,y| Math.log(y)     }
  sx2   = sigma(xys) { |x,y| x * x           }
  sx    = sigma xs

  c = n * sx2 - sx ** 2
  a = (slny * sx2 - sx * sxlny) / c
  b = ( n * sxlny - sx * slny ) / c

  return Math.exp(a), b, fit_error(xys) { |x| Math.exp(a + b * x) }
end

    		
  





    
      

  

  
    #fit_linear(xs, ys)  ⇒ Object 
  

  

  




  

    

Fits the functional form: a + bx.



Takes x and y values and returns [a, b, r^2].



See: mathworld.wolfram.com/LeastSquaresFitting.html



  





  



  

    
      


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# File 'lib/minitest/benchmark.rb', line 239

def fit_linear xs, ys
  n   = xs.size
  xys = xs.zip(ys)
  sx  = sigma xs
  sy  = sigma ys
  sx2 = sigma(xs)  { |x|   x ** 2 }
  sxy = sigma(xys) { |x,y| x * y  }

  c = n * sx2 - sx**2
  a = (sy * sx2 - sx * sxy) / c
  b = ( n * sxy - sx * sy ) / c

  return a, b, fit_error(xys) { |x| a + b * x }
end

    		
  





    
      

  

  
    #fit_power(xs, ys)  ⇒ Object 
  

  

  




  

    

To fit a functional form: y = ax^b.



Takes x and y values and returns [a, b, r^2].



See: mathworld.wolfram.com/LeastSquaresFittingPowerLaw.html



  





  



  

    
      


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# File 'lib/minitest/benchmark.rb', line 261

def fit_power xs, ys
  n       = xs.size
  xys     = xs.zip(ys)
  slnxlny = sigma(xys) { |x, y| Math.log(x) * Math.log(y) }
  slnx    = sigma(xs)  { |x   | Math.log(x)               }
  slny    = sigma(ys)  { |   y| Math.log(y)               }
  slnx2   = sigma(xs)  { |x   | Math.log(x) ** 2          }

  b = (n * slnxlny - slnx * slny) / (n * slnx2 - slnx ** 2);
  a = (slny - b * slnx) / n

  return Math.exp(a), b, fit_error(xys) { |x| (Math.exp(a) * (x ** b)) }
end

    		
  





    
      

  

  
    #io  ⇒ Object 
  

  

  




  

    

Return the output IO object



  





  



  

    
      


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# File 'lib/minitest/unit.rb', line 1110

def io
  @__io__ = true
  MiniTest::Unit.output
end

    		
  





    
      

  

  
    #io?  ⇒ Boolean 
  

  

  




  

    

Have we hooked up the IO yet?



  





  

Returns:


    
  
    
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        (Boolean)
      
      
      
    
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# File 'lib/minitest/unit.rb', line 1118

def io?
  @__io__
end

    		
  





    
      

  

  
    #passed?  ⇒ Boolean 
  

  

  




  

    

Returns true if the test passed.



  





  

Returns:


    
  
    
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        (Boolean)
      
      
      
    
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# File 'lib/minitest/unit.rb', line 1171

def passed?
  @passed
end

    		
  





    
      

  

  
    #run(runner)  ⇒ Object 
  

  

  




  

    

Runs the tests reporting the status to runner



  





  



  

    
      


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# File 'lib/minitest/unit.rb', line 1054

def run runner
  trap "INFO" do
    runner.report.each_with_index do |msg, i|
      warn "\n%3d) %s" % [i + 1, msg]
    end
    warn ''
    time = runner.start_time ? Time.now - runner.start_time : 0
    warn "Current Test: %s#%s %.2fs" % [self.class, self.__name__, time]
    runner.status $stderr
  end if SUPPORTS_INFO_SIGNAL

  result = ""
  begin
    @passed = nil
    self.before_setup
    self.setup
    self.after_setup
    self.run_test self.__name__
    result = "." unless io?
    @passed = true
  rescue *PASSTHROUGH_EXCEPTIONS
    raise
  rescue Exception => e
    @passed = false
    result = runner.puke self.class, self.__name__, e
  ensure
    %w{ before_teardown teardown after_teardown }.each do |hook|
      begin
        self.send hook
      rescue *PASSTHROUGH_EXCEPTIONS
        raise
      rescue Exception => e
        result = runner.puke self.class, self.__name__, e
      end
    end
    trap 'INFO', 'DEFAULT' if SUPPORTS_INFO_SIGNAL
  end
  result
end

    		
  





    
      

  

  
    #run_setup_hooks  ⇒ Object 
  

  

  




  

    

:nodoc:



  





  



  

    
      


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# File 'lib/minitest/unit.rb', line 1253

def run_setup_hooks # :nodoc:
  self.class.setup_hooks.each do |hook|
    if hook.respond_to?(:arity) && hook.arity == 1
      hook.call(self)
    else
      hook.call
    end
  end
end

    		
  





    
      

  

  
    #run_teardown_hooks  ⇒ Object 
  

  

  




  

    

:nodoc:



  





  



  

    
      


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# File 'lib/minitest/unit.rb', line 1302

def run_teardown_hooks # :nodoc:
  self.class.teardown_hooks.reverse.each do |hook|
    if hook.respond_to?(:arity) && hook.arity == 1
      hook.call(self)
    else
      hook.call
    end
  end
end

    		
  





    
      

  

  
    #setup  ⇒ Object 
  

  

  




  

    

Runs before every test. Use this to refactor test initialization.



  





  



  

    
      


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# File 'lib/minitest/unit.rb', line 1178

def setup; end

    		
  





    
      

  

  
    #sigma(enum, &block)  ⇒ Object 
  

  

  




  

    

Enumerates over enum mapping block if given, returning the sum of the result. Eg:



sigma([1, 2, 3])                # => 1 + 2 + 3 => 7
sigma([1, 2, 3]) { |n| n ** 2 } # => 1 + 4 + 9 => 14




  





  



  

    
      


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# File 'lib/minitest/benchmark.rb', line 282

def sigma enum, &block
  enum = enum.map(&block) if block
  enum.inject { |sum, n| sum + n }
end

    		
  





    
      

  

  
    #teardown  ⇒ Object 
  

  

  




  

    

Runs after every test. Use this to refactor test cleanup.



  





  



  

    
      


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# File 'lib/minitest/unit.rb', line 1194

def teardown; end

    		
  





    
      

  

  
    #validation_for_fit(msg, threshold)  ⇒ Object 
  

  

  




  

    

Returns a proc that calls the specified fit method and asserts that the error is within a tolerable threshold.



  





  



  

    
      


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# File 'lib/minitest/benchmark.rb', line 291

def validation_for_fit msg, threshold
  proc do |range, times|
    a, b, rr = send "fit_#{msg}", range, times
    assert_operator rr, :>=, threshold
    [a, b, rr]
  end
end