1 files changed, 95 insertions, 0 deletions
diff --git a/spec/ruby/core/array/rindex_spec.rb b/spec/ruby/core/array/rindex_spec.rb
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+++ b/spec/ruby/core/array/rindex_spec.rb
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+require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
+require_relative '../enumerable/shared/enumeratorized'
+
+# Modifying a collection while the contents are being iterated
+# gives undefined behavior. See
+# https://blade.ruby-lang.org/ruby-core/23633
+
+describe "Array#rindex" do
+  it "returns the first index backwards from the end where element == to object" do
+    key = 3
+    uno = mock('one')
+    dos = mock('two')
+    tres = mock('three')
+    tres.should_receive(:==).any_number_of_times.and_return(false)
+    dos.should_receive(:==).any_number_of_times.and_return(true)
+    uno.should_not_receive(:==)
+    ary = [uno, dos, tres]
+
+    ary.rindex(key).should == 1
+  end
+
+  it "returns size-1 if last element == to object" do
+    [2, 1, 3, 2, 5].rindex(5).should == 4
+  end
+
+  it "returns 0 if only first element == to object" do
+    [2, 1, 3, 1, 5].rindex(2).should == 0
+  end
+
+  it "returns nil if no element == to object" do
+    [1, 1, 3, 2, 1, 3].rindex(4).should == nil
+  end
+
+  it "returns correct index even after delete_at" do
+    array = ["fish", "bird", "lion", "cat"]
+    array.delete_at(0)
+    array.rindex("lion").should == 1
+  end
+
+  it "properly handles empty recursive arrays" do
+    empty = ArraySpecs.empty_recursive_array
+    empty.rindex(empty).should == 0
+    empty.rindex(1).should be_nil
+  end
+
+  it "properly handles recursive arrays" do
+    array = ArraySpecs.recursive_array
+    array.rindex(1).should == 0
+    array.rindex(array).should == 7
+  end
+
+  it "accepts a block instead of an argument" do
+    [4, 2, 1, 5, 1, 3].rindex { |x| x < 2 }.should == 4
+  end
+
+  it "ignores the block if there is an argument" do
+    -> {
+      [4, 2, 1, 5, 1, 3].rindex(5) { |x| x < 2 }.should == 3
+    }.should complain(/given block not used/)
+  end
+
+  it "rechecks the array size during iteration" do
+    ary = [4, 2, 1, 5, 1, 3]
+    seen = []
+    ary.rindex { |x| seen << x; ary.clear; false }
+
+    seen.should == [3]
+  end
+
+  it "tolerates increasing an array size during iteration" do
+    array = [:a, :b, :c]
+    ScratchPad.record []
+    i = 0
+
+    array.rindex do |e|
+      ScratchPad << e
+      array.prepend i if i < 100
+      i += 1
+      false
+    end
+
+    ScratchPad.recorded.should == [:c, :a, 1]
+  end
+
+  describe "given no argument and no block" do
+    it "produces an Enumerator" do
+      enum = [4, 2, 1, 5, 1, 3].rindex
+      enum.should be_an_instance_of(Enumerator)
+      enum.each { |x| x < 2 }.should == 4
+    end
+  end
+
+  it_behaves_like :enumeratorized_with_unknown_size, :bsearch, [1,2,3]
+end