1 files changed, 30 insertions, 0 deletions
diff --git a/spec/ruby/core/tracepoint/allow_reentry_spec.rb b/spec/ruby/core/tracepoint/allow_reentry_spec.rb
new file mode 100644
index 0000000000..475cca29a9
--- /dev/null
+++ b/spec/ruby/core/tracepoint/allow_reentry_spec.rb
@@ -0,0 +1,30 @@
+require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
+
+describe 'TracePoint.allow_reentry' do
+  it 'allows the reentrance in a given block' do
+    event_lines = []
+    l1 = l2 = l3 = l4 = nil
+    TracePoint.new(:line) do |tp|
+      next unless TracePointSpec.target_thread?
+
+      event_lines << tp.lineno
+      next if (__LINE__ + 2 .. __LINE__ + 4).cover?(tp.lineno)
+      TracePoint.allow_reentry do
+        a = 1; l3 = __LINE__
+        b = 2; l4 = __LINE__
+      end
+    end.enable do
+      c = 3; l1 = __LINE__
+      d = 4; l2 = __LINE__
+    end
+
+    event_lines.should == [l1, l3, l4, l2, l3, l4]
+  end
+
+  it 'raises RuntimeError when not called inside a TracePoint' do
+    -> {
+      TracePoint.allow_reentry{}
+    }.should.raise(RuntimeError)
+  end
+end