1 files changed, 116 insertions, 0 deletions
diff --git a/spec/ruby/core/hash/reject_spec.rb b/spec/ruby/core/hash/reject_spec.rb
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+++ b/spec/ruby/core/hash/reject_spec.rb
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+require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
+require_relative 'shared/iteration'
+require_relative '../enumerable/shared/enumeratorized'
+
+describe "Hash#reject" do
+  it "returns a new hash removing keys for which the block yields true" do
+    h = { 1=>false, 2=>true, 3=>false, 4=>true }
+    h.reject { |k,v| v }.keys.sort.should == [1,3]
+  end
+
+  it "is equivalent to hsh.dup.delete_if" do
+    h = { a: 'a', b: 'b', c: 'd' }
+    h.reject { |k,v| k == 'd' }.should == (h.dup.delete_if { |k, v| k == 'd' })
+
+    all_args_reject = []
+    all_args_delete_if = []
+    h = { 1 => 2, 3 => 4 }
+    h.reject { |*args| all_args_reject << args }
+    h.delete_if { |*args| all_args_delete_if << args }
+    all_args_reject.should == all_args_delete_if
+
+    h = { 1 => 2 }
+    # dup doesn't copy singleton methods
+    def h.to_a() end
+    h.reject { false }.to_a.should == [[1, 2]]
+  end
+
+  context "with extra state" do
+    it "returns Hash instance for subclasses" do
+      HashSpecs::MyHash[1 => 2, 3 => 4].reject { false }.should.is_a?(Hash)
+      HashSpecs::MyHash[1 => 2, 3 => 4].reject { true }.should.is_a?(Hash)
+    end
+  end
+
+  it "processes entries with the same order as reject!" do
+    h = { a: 1, b: 2, c: 3, d: 4 }
+
+    reject_pairs = []
+    reject_bang_pairs = []
+    h.dup.reject { |*pair| reject_pairs << pair }
+    h.reject! { |*pair| reject_bang_pairs << pair }
+
+    reject_pairs.should == reject_bang_pairs
+  end
+
+  it "does not retain the default value" do
+    h = Hash.new(1)
+    h.reject { false }.default.should == nil
+    h[:a] = 1
+    h.reject { false }.default.should == nil
+  end
+
+  it "does not retain the default_proc" do
+    pr = proc { |h, k| h[k] = [] }
+    h = Hash.new(&pr)
+    h.reject { false }.default_proc.should == nil
+    h[:a] = 1
+    h.reject { false }.default_proc.should == nil
+  end
+
+  it "retains compare_by_identity flag" do
+    h = { a: 9, c: 4 }.compare_by_identity
+    h2 = h.reject { |k, _| k == :a }
+    h2.compare_by_identity?.should == true
+  end
+
+  it_behaves_like :hash_iteration_no_block, :reject
+  it_behaves_like :enumeratorized_with_origin_size, :reject, { 1 => 2, 3 => 4, 5 => 6 }
+end
+
+describe "Hash#reject!" do
+  it "removes keys from self for which the block yields true" do
+    hsh = {}
+    (1 .. 10).each { |k| hsh[k] = (k % 2 == 0) }
+    hsh.reject! { |k,v| v }
+    hsh.keys.sort.should == [1,3,5,7,9]
+  end
+
+  it "removes all entries if the block is true" do
+    h = { a: 1, b: 2, c: 3 }
+    h.reject! { |k,v| true }.should.equal?(h)
+    h.should == {}
+  end
+
+  it "is equivalent to delete_if if changes are made" do
+    hsh = { a: 1 }
+    hsh.reject! { |k,v| v < 2 }.should == hsh.dup.delete_if { |k, v| v < 2 }
+  end
+
+  it "returns nil if no changes were made" do
+    { a: 1 }.reject! { |k,v| v > 1 }.should == nil
+  end
+
+  it "processes entries with the same order as delete_if" do
+    h = { a: 1, b: 2, c: 3, d: 4 }
+
+    reject_bang_pairs = []
+    delete_if_pairs = []
+    h.dup.reject! { |*pair| reject_bang_pairs << pair }
+    h.dup.delete_if { |*pair| delete_if_pairs << pair }
+
+    reject_bang_pairs.should == delete_if_pairs
+  end
+
+  it "raises a FrozenError if called on a frozen instance that is modified" do
+    -> { HashSpecs.empty_frozen_hash.reject! { true } }.should.raise(FrozenError)
+  end
+
+  it "raises a FrozenError if called on a frozen instance that would not be modified" do
+    -> { HashSpecs.frozen_hash.reject! { false } }.should.raise(FrozenError)
+  end
+
+  it_behaves_like :hash_iteration_no_block, :reject!
+  it_behaves_like :enumeratorized_with_origin_size, :reject!, { 1 => 2, 3 => 4, 5 => 6 }
+end