Update to ruby/spec@f8a2d54

1 files changed, 36 insertions, 0 deletions

diff --git a/spec/ruby/core/enumerator/produce_spec.rb b/spec/ruby/core/enumerator/produce_spec.rb
new file mode 100644
index 0000000000..f6f1dcd429
--- /dev/null
+++ b/spec/ruby/core/enumerator/produce_spec.rb
@@ -0,0 +1,36 @@
+require_relative '../../spec_helper'
+
+ruby_version_is "2.7" do
+  describe "Enumerator.produce" do
+    it "creates an infinite enumerator" do
+      enum = Enumerator.produce(0) { |prev| prev + 1 }
+      enum.take(5).should == [0, 1, 2, 3, 4]
+    end
+
+    it "terminates iteration when block raises StopIteration exception" do
+      enum = Enumerator.produce(0) do | prev|
+        raise StopIteration if prev >= 2
+        prev + 1
+      end
+
+      enum.to_a.should == [0, 1, 2]
+    end
+
+    context "when initial value skipped" do
+      it "uses nil instead" do
+        ScratchPad.record []
+        enum = Enumerator.produce { |prev| ScratchPad << prev; (prev || 0) + 1 }
+
+        enum.take(3).should == [1, 2, 3]
+        ScratchPad.recorded.should == [nil, 1, 2]
+      end
+
+      it "starts enumerable from result of first block call" do
+        array = "a\nb\nc\nd".lines
+        lines = Enumerator.produce { array.shift }.take_while { |s| s }
+
+        lines.should == ["a\n", "b\n", "c\n", "d"]
+      end
+    end
+  end
+end