1 files changed, 38 insertions, 0 deletions
diff --git a/spec/ruby/core/exception/cause_spec.rb b/spec/ruby/core/exception/cause_spec.rb
new file mode 100644
index 0000000000..cfc15bdda3
--- /dev/null
+++ b/spec/ruby/core/exception/cause_spec.rb
@@ -0,0 +1,38 @@
+require_relative '../../spec_helper'
+
+describe "Exception#cause" do
+  it "returns the active exception when an exception is raised" do
+    begin
+      raise Exception, "the cause"
+    rescue Exception => cause
+      -> {
+        raise RuntimeError, "the consequence"
+      }.should.raise(RuntimeError, "the consequence", cause:)
+    end
+  end
+
+  it "is set for user errors caused by internal errors" do
+    begin
+      1 / 0
+    rescue => cause
+      -> { raise "foo" }.should.raise(RuntimeError, cause:)
+    end
+  end
+
+  it "is set for internal errors caused by user errors" do
+    cause = RuntimeError.new "cause"
+    begin
+      raise cause
+    rescue
+      -> { 1 / 0 }.should.raise(ZeroDivisionError, cause:)
+    end
+  end
+
+  it "is not set to the exception itself when it is re-raised" do
+    begin
+      raise RuntimeError
+    rescue RuntimeError => e
+      -> { raise e }.should.raise(RuntimeError, cause: nil)
+    end
+  end
+end