1# power_assert.rb
2#
3# Copyright (C) 2014 Kazuki Tsujimoto
4
5begin
6  unless defined?(Byebug)
7    captured = false
8    TracePoint.new(:return, :c_return) do |tp|
9      captured = true
10      unless tp.binding and tp.return_value
11        raise ''
12      end
13    end.enable { __id__ }
14    raise '' unless captured
15  end
16rescue
17  raise LoadError, 'Fully compatible TracePoint API required'
18end
19
20require 'power_assert/version'
21require 'power_assert/configuration'
22require 'power_assert/context'
23
24module PowerAssert
25  POWER_ASSERT_LIB_DIR = File.dirname(caller_locations(1, 1).first.path)
26  INTERNAL_LIB_DIRS = {PowerAssert => POWER_ASSERT_LIB_DIR}
27  private_constant :POWER_ASSERT_LIB_DIR, :INTERNAL_LIB_DIRS
28
29  # For backward compatibility
30  IGNORED_LIB_DIRS = INTERNAL_LIB_DIRS
31  private_constant :IGNORED_LIB_DIRS
32  if respond_to?(:deprecate_constant)
33    deprecate_constant :IGNORED_LIB_DIRS
34  end
35
36  class << self
37    def start(assertion_proc_or_source, assertion_method: nil, source_binding: TOPLEVEL_BINDING)
38      if respond_to?(:clear_global_method_cache, true)
39        clear_global_method_cache
40      end
41      yield BlockContext.new(assertion_proc_or_source, assertion_method, source_binding)
42    end
43
44    def trace(frame)
45      begin
46        raise 'Byebug is not started yet' unless Byebug.started?
47      rescue NameError
48        raise "PowerAssert.#{__method__} requires Byebug"
49      end
50      ctx = TraceContext.new(frame._binding)
51      ctx.enable
52      ctx
53    end
54
55    def app_caller_locations
56      caller_locations.drop_while {|i| internal_file?(i.path) }.take_while {|i| ! internal_file?(i.path) }
57    end
58
59    def app_context?
60      top_frame = caller_locations.drop_while {|i| i.path.start_with?(POWER_ASSERT_LIB_DIR) }.first
61      top_frame and ! internal_file?(top_frame.path)
62    end
63
64    private
65
66    def internal_file?(file)
67      setup_internal_lib_dir(Byebug, :attach, 2) if defined?(Byebug)
68      setup_internal_lib_dir(PryByebug, :start_with_pry_byebug, 2, Pry) if defined?(PryByebug)
69      INTERNAL_LIB_DIRS.find do |_, dir|
70        file.start_with?(dir)
71      end
72    end
73
74    def setup_internal_lib_dir(lib, mid, depth, lib_obj = lib)
75      unless INTERNAL_LIB_DIRS.key?(lib)
76        INTERNAL_LIB_DIRS[lib] = lib_dir(lib_obj, mid, depth)
77      end
78    rescue NameError
79    end
80
81    def lib_dir(obj, mid, depth)
82      File.expand_path('../' * depth, obj.method(mid).source_location[0])
83    end
84
85    if defined?(RubyVM)
86      CLEAR_CACHE_ISEQ = RubyVM::InstructionSequence.compile('using PowerAssert.const_get(:Empty)')
87      private_constant :CLEAR_CACHE_ISEQ
88
89      def clear_global_method_cache
90        CLEAR_CACHE_ISEQ.eval
91      end
92    end
93  end
94
95  module Empty
96  end
97  private_constant :Empty
98end
99