1 files changed, 83 insertions, 0 deletions
diff --git a/spec/ruby/core/hash/select_spec.rb b/spec/ruby/core/hash/select_spec.rb
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+++ b/spec/ruby/core/hash/select_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/iteration', __FILE__)
+require File.expand_path('../../enumerable/shared/enumeratorized', __FILE__)
+
+describe "Hash#select" do
+  before :each do
+    @hsh = { 1 => 2, 3 => 4, 5 => 6 }
+    @empty = {}
+  end
+
+  it "yields two arguments: key and value" do
+    all_args = []
+    { 1 => 2, 3 => 4 }.select { |*args| all_args << args }
+    all_args.sort.should == [[1, 2], [3, 4]]
+  end
+
+  it "returns a Hash of entries for which block is true" do
+    a_pairs = { 'a' => 9, 'c' => 4, 'b' => 5, 'd' => 2 }.select { |k,v| v % 2 == 0 }
+    a_pairs.should be_an_instance_of(Hash)
+    a_pairs.sort.should == [['c', 4], ['d', 2]]
+  end
+
+  it "processes entries with the same order as reject" do
+    h = { a: 9, c: 4, b: 5, d: 2 }
+
+    select_pairs = []
+    reject_pairs = []
+    h.dup.select { |*pair| select_pairs << pair }
+    h.reject { |*pair| reject_pairs << pair }
+
+    select_pairs.should == reject_pairs
+  end
+
+  it "returns an Enumerator when called on a non-empty hash without a block" do
+    @hsh.select.should be_an_instance_of(Enumerator)
+  end
+
+  it "returns an Enumerator when called on an empty hash without a block" do
+    @empty.select.should be_an_instance_of(Enumerator)
+  end
+
+  it_behaves_like(:hash_iteration_no_block, :select)
+  it_behaves_like(:enumeratorized_with_origin_size, :select, { 1 => 2, 3 => 4, 5 => 6 })
+end
+
+describe "Hash#select!" do
+  before :each do
+    @hsh = { 1 => 2, 3 => 4, 5 => 6 }
+    @empty = {}
+  end
+
+  it "is equivalent to keep_if if changes are made" do
+    h = { a: 2 }
+    h.select! { |k,v| v <= 1 }.should equal h
+
+    h = { 1 => 2, 3 => 4 }
+    all_args_select = []
+    h.dup.select! { |*args| all_args_select << args }
+    all_args_select.should == [[1, 2], [3, 4]]
+  end
+
+  it "removes all entries if the block is false" do
+    h = { a: 1, b: 2, c: 3 }
+    h.select! { |k,v| false }.should equal(h)
+    h.should == {}
+  end
+
+  it "returns nil if no changes were made" do
+    { a: 1 }.select! { |k,v| v <= 1 }.should == nil
+  end
+
+  it "raises a RuntimeError if called on an empty frozen instance" do
+    lambda { HashSpecs.empty_frozen_hash.select! { false } }.should raise_error(RuntimeError)
+  end
+
+  it "raises a RuntimeError if called on a frozen instance that would not be modified" do
+    lambda { HashSpecs.frozen_hash.select! { true } }.should raise_error(RuntimeError)
+  end
+
+  it_behaves_like(:hash_iteration_no_block, :select!)
+  it_behaves_like(:enumeratorized_with_origin_size, :select!, { 1 => 2, 3 => 4, 5 => 6 })
+end