summaryrefslogtreecommitdiff
path: root/spec/ruby/core/proc/parameters_spec.rb
blob: 972596d2ea8809b3c8a9af621fd2a0b7b7a9139c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
require_relative '../../spec_helper'

describe "Proc#parameters" do
  it "returns an empty Array for a proc expecting no parameters" do
    proc {}.parameters.should == []
  end

  it "returns an Array of Arrays for a proc expecting parameters" do
    p = proc {|x| }
    p.parameters.should be_an_instance_of(Array)
    p.parameters.first.should be_an_instance_of(Array)
  end

  it "sets the first element of each sub-Array to :opt for optional arguments" do
    proc {|x| }.parameters.first.first.should == :opt
    proc {|y,*x| }.parameters.first.first.should == :opt
  end

  it "regards named parameters in procs as optional" do
    proc {|x| }.parameters.first.first.should == :opt
  end

  ruby_version_is "3.2" do
    it "sets the first element of each sub-Array to :req for required argument if lambda keyword used" do
      proc {|x| }.parameters(lambda: true).first.first.should == :req
      proc {|y,*x| }.parameters(lambda: true).first.first.should == :req
    end

    it "regards named parameters in procs as required if lambda keyword used" do
      proc {|x| }.parameters(lambda: true).first.first.should == :req
    end

    it "regards named parameters in lambda as optional if lambda: false keyword used" do
      -> x { }.parameters(lambda: false).first.first.should == :opt
    end

    it "regards named parameters in procs and lambdas as required if lambda keyword is truthy" do
      proc {|x| }.parameters(lambda: 123).first.first.should == :req
      -> x { }.parameters(lambda: 123).first.first.should == :req
    end

    it "ignores the lambda keyword if it is nil" do
      proc {|x|}.parameters(lambda: nil).first.first.should == :opt
      -> x { }.parameters(lambda: nil).first.first.should == :req
    end
  end

  it "regards optional keyword parameters in procs as optional" do
    proc {|x: :y| }.parameters.first.first.should == :key
  end

  it "regards parameters with default values as optional" do
    -> x=1 { }.parameters.first.first.should == :opt
    proc {|x=1| }.parameters.first.first.should == :opt
  end

  it "sets the first element of each sub-Array to :req for required arguments" do
    -> x, y=[] { }.parameters.first.first.should == :req
    -> y, *x { }.parameters.first.first.should == :req
  end

  it "regards named parameters in lambdas as required" do
    -> x { }.parameters.first.first.should == :req
  end

  it "regards keyword parameters in lambdas as required" do
    eval("lambda {|x:| }").parameters.first.first.should == :keyreq
  end

  it "sets the first element of each sub-Array to :rest for parameters prefixed with asterisks" do
    -> *x { }.parameters.first.first.should == :rest
    -> x, *y { }.parameters.last.first.should == :rest
    proc {|*x| }.parameters.first.first.should == :rest
    proc {|x,*y| }.parameters.last.first.should == :rest
  end

  it "sets the first element of each sub-Array to :keyrest for parameters prefixed with double asterisks" do
    -> **x { }.parameters.first.first.should == :keyrest
    -> x, **y { }.parameters.last.first.should == :keyrest
    proc {|**x| }.parameters.first.first.should == :keyrest
    proc {|x,**y| }.parameters.last.first.should == :keyrest
  end

  it "sets the first element of each sub-Array to :block for parameters prefixed with ampersands" do
    -> &x { }.parameters.first.first.should == :block
    -> x, &y { }.parameters.last.first.should == :block
    proc {|&x| }.parameters.first.first.should == :block
    proc {|x,&y| }.parameters.last.first.should == :block
  end

  it "sets the second element of each sub-Array to the name of the argument" do
    -> x { }.parameters.first.last.should == :x
    -> x=Math::PI { }.parameters.first.last.should == :x
    -> an_argument, glark, &foo { }.parameters[1].last.should == :glark
    -> *rest { }.parameters.first.last.should == :rest
    -> &block { }.parameters.first.last.should == :block
    proc {|x| }.parameters.first.last.should == :x
    proc {|x=Math::PI| }.parameters.first.last.should == :x
    proc {|an_argument, glark, &foo| }.parameters[1].last.should == :glark
    proc {|*rest| }.parameters.first.last.should == :rest
    proc {|&block| }.parameters.first.last.should == :block
  end

  it "ignores unnamed rest arguments" do
    -> x {}.parameters.should == [[:req, :x]]
  end

  it "ignores implicit rest arguments" do
    proc { |x, | }.parameters.should == [[:opt, :x]]
    -> x { }.parameters.should == [[:req, :x]]
  end

  ruby_version_is '3.2' do
    it "adds rest arg with name * for \"star\" argument" do
      -> * {}.parameters.should == [[:rest, :*]]
    end

    it "adds keyrest arg with ** as a name for \"double star\" argument" do
      -> ** {}.parameters.should == [[:keyrest, :**]]
    end
  end

  ruby_version_is ''...'3.2' do
    it "adds nameless rest arg for \"star\" argument" do
      -> * {}.parameters.should == [[:rest]]
    end

    it "adds nameless keyrest arg for \"double star\" argument" do
      -> ** {}.parameters.should == [[:keyrest]]
    end
  end

  ruby_version_is '3.1' do
    it "adds block arg with name & for anonymous block argument" do
      eval('-> & {}.parameters').should == [[:block, :&]]
    end
  end

  it "does not add locals as block options with a block and splat" do
    -> *args, &blk do
      local_is_not_parameter = {}
    end.parameters.should == [[:rest, :args], [:block, :blk]]
    proc do |*args, &blk|
      local_is_not_parameter = {}
    end.parameters.should == [[:rest, :args], [:block, :blk]]
  end

  it "returns all parameters defined with the name _ as _" do
    proc = proc {|_, _, _ = 1, *_, _:, _: 2, **_, &_| }
    proc.parameters.should == [
      [:opt, :_],
      [:opt, :_],
      [:opt, :_],
      [:rest, :_],
      [:keyreq, :_],
      [:key, :_],
      [:keyrest, :_],
      [:block, :_]
    ]

    lambda = -> _, _, _ = 1, *_, _:, _: 2, **_, &_ {}
    lambda.parameters.should == [
      [:req, :_],
      [:req, :_],
      [:opt, :_],
      [:rest, :_],
      [:keyreq, :_],
      [:key, :_],
      [:keyrest, :_],
      [:block, :_]
    ]
  end

  it "returns :nokey for **nil parameter" do
    proc { |**nil| }.parameters.should == [[:nokey]]
  end
end