aboutsummaryrefslogtreecommitdiffstats
path: root/spec/ruby/core/hash/shift_spec.rb
diff options
context:
space:
mode:
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/hash/shift_spec.rb
parent75bfc6440d595bf339007f4fb280fd4d743e89c1 (diff)
downloadruby-1d15d5f08032acf1b7bceacbb450d617ff6e0931.tar.gz
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
Diffstat (limited to 'spec/ruby/core/hash/shift_spec.rb')
-rw-r--r--spec/ruby/core/hash/shift_spec.rb64
1 files changed, 64 insertions, 0 deletions
diff --git a/spec/ruby/core/hash/shift_spec.rb b/spec/ruby/core/hash/shift_spec.rb
new file mode 100644
index 0000000000..3991da9656
--- /dev/null
+++ b/spec/ruby/core/hash/shift_spec.rb
@@ -0,0 +1,64 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+
+describe "Hash#shift" do
+ it "removes a pair from hash and return it" do
+ h = { a: 1, b: 2, "c" => 3, nil => 4, [] => 5 }
+ h2 = h.dup
+
+ h.size.times do |i|
+ r = h.shift
+ r.should be_kind_of(Array)
+ h2[r.first].should == r.last
+ h.size.should == h2.size - i - 1
+ end
+
+ h.should == {}
+ end
+
+ # MRI explicitly implements this behavior
+ it "allows shifting entries while iterating" do
+ h = { a: 1, b: 2, c: 3 }
+ visited = []
+ shifted = []
+ h.each_pair { |k,v|
+ visited << k
+ shifted << h.shift
+ }
+ visited.should == [:a, :b, :c]
+ shifted.should == [[:a, 1], [:b, 2], [:c, 3]]
+ h.should == {}
+ end
+
+ it "calls #default with nil if the Hash is empty" do
+ h = {}
+ def h.default(key)
+ key.should == nil
+ :foo
+ end
+ h.shift.should == :foo
+ end
+
+ it "returns nil from an empty hash" do
+ {}.shift.should == nil
+ end
+
+ it "returns (computed) default for empty hashes" do
+ Hash.new(5).shift.should == 5
+ h = Hash.new { |*args| args }
+ h.shift.should == [h, nil]
+ end
+
+ it "preserves Hash invariants when removing the last item" do
+ h = { :a => 1, :b => 2 }
+ h.shift.should == [:a, 1]
+ h.shift.should == [:b, 2]
+ h[:c] = 3
+ h.should == {:c => 3}
+ end
+
+ it "raises a RuntimeError if called on a frozen instance" do
+ lambda { HashSpecs.frozen_hash.shift }.should raise_error(RuntimeError)
+ lambda { HashSpecs.empty_frozen_hash.shift }.should raise_error(RuntimeError)
+ end
+end