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authoreregon <eregon@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2017-09-20 20:18:52 +0000
committereregon <eregon@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2017-09-20 20:18:52 +0000
commit1d15d5f08032acf1b7bceacbb450d617ff6e0931 (patch)
treea3785a79899302bc149e4a6e72f624ac27dc1f10 /spec/ruby/core/enumerable/min_by_spec.rb
parent75bfc6440d595bf339007f4fb280fd4d743e89c1 (diff)
Move spec/rubyspec to spec/ruby for consistency
* Other ruby implementations use the spec/ruby directory. [Misc #13792] [ruby-core:82287] git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@59979 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
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diff --git a/spec/ruby/core/enumerable/min_by_spec.rb b/spec/ruby/core/enumerable/min_by_spec.rb
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+++ b/spec/ruby/core/enumerable/min_by_spec.rb
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+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+require File.expand_path('../shared/enumerable_enumeratorized', __FILE__)
+
+describe "Enumerable#min_by" do
+ it "returns an enumerator if no block" do
+ EnumerableSpecs::Numerous.new(42).min_by.should be_an_instance_of(Enumerator)
+ end
+
+ it "returns nil if #each yields no objects" do
+ EnumerableSpecs::Empty.new.min_by {|o| o.nonesuch }.should == nil
+ end
+
+ it "returns the object for whom the value returned by block is the smallest" do
+ EnumerableSpecs::Numerous.new(*%w[3 2 1]).min_by {|obj| obj.to_i }.should == '1'
+ EnumerableSpecs::Numerous.new(*%w[five three]).min_by {|obj| obj.length }.should == 'five'
+ end
+
+ it "returns the object that appears first in #each in case of a tie" do
+ a, b, c = '2', '1', '1'
+ EnumerableSpecs::Numerous.new(a, b, c).min_by {|obj| obj.to_i }.should equal(b)
+ end
+
+ it "uses min.<=>(current) to determine order" do
+ a, b, c = (1..3).map{|n| EnumerableSpecs::ReverseComparable.new(n)}
+
+ # Just using self here to avoid additional complexity
+ EnumerableSpecs::Numerous.new(a, b, c).min_by {|obj| obj }.should == c
+ end
+
+ it "is able to return the minimum for enums that contain nils" do
+ enum = EnumerableSpecs::Numerous.new(nil, nil, true)
+ enum.min_by {|o| o.nil? ? 0 : 1 }.should == nil
+ enum.min_by {|o| o.nil? ? 1 : 0 }.should == true
+ end
+
+ it "gathers whole arrays as elements when each yields multiple" do
+ multi = EnumerableSpecs::YieldsMulti.new
+ multi.min_by {|e| e.size}.should == [1, 2]
+ end
+
+ it_behaves_like :enumerable_enumeratorized_with_origin_size, :min_by
+
+ context "when called with an argument n" do
+ before :each do
+ @enum = EnumerableSpecs::Numerous.new(101, 55, 1, 20, 33, 500, 60)
+ end
+
+ context "without a block" do
+ it "returns an enumerator" do
+ @enum.min_by(2).should be_an_instance_of(Enumerator)
+ end
+ end
+
+ context "with a block" do
+ it "returns an array containing the minimum n elements based on the block's value" do
+ result = @enum.min_by(3) { |i| i.to_s }
+ result.should == [1, 101, 20]
+ end
+
+ context "on a enumerable of length x where x < n" do
+ it "returns an array containing the minimum n elements of length n" do
+ result = @enum.min_by(500) { |i| i.to_s }
+ result.length.should == 7
+ end
+ end
+
+ context "when n is negative" do
+ it "raises an ArgumentError" do
+ lambda { @enum.min_by(-1) { |i| i.to_s } }.should raise_error(ArgumentError)
+ end
+ end
+ end
+
+ context "when n is nil" do
+ it "returns the minimum element" do
+ @enum.min_by(nil) { |i| i.to_s }.should == 1
+ end
+ end
+ end
+end