Adding Enumerable#filter_map

[Feature #15323]
Closes: https://github.com/ruby/ruby/pull/2017

1 files changed, 26 insertions, 0 deletions

diff --git a/spec/ruby/core/enumerable/filter_map_spec.rb b/spec/ruby/core/enumerable/filter_map_spec.rb
new file mode 100644
index 0000000000..31acc277b4
--- /dev/null
+++ b/spec/ruby/core/enumerable/filter_map_spec.rb
@@ -0,0 +1,26 @@
+require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
+
+ruby_version_is '2.7' do
+  describe 'Enumerable#filter_map' do
+    before :each do
+      @numerous = EnumerableSpecs::Numerous.new(*(1..8).to_a)
+    end
+
+    it 'returns an empty array if there are no elements' do
+      EnumerableSpecs::Empty.new.filter_map { true }.should == []
+    end
+
+    it 'returns an array with truthy results of passing each element to block' do
+      @numerous.filter_map { |i| i * 2 if i.even? }.should == [4, 8, 12, 16]
+      @numerous.filter_map { |i| i * 2 }.should == [2, 4, 6, 8, 10, 12, 14, 16]
+      @numerous.filter_map { 0 }.should == [0, 0, 0, 0, 0, 0, 0, 0]
+      @numerous.filter_map { false }.should == []
+      @numerous.filter_map { nil }.should == []
+    end
+
+    it 'returns an enumerator when no block given' do
+      @numerous.filter_map.should be_an_instance_of(Enumerator)
+    end
+  end
+end