1 files changed, 32 insertions, 0 deletions
diff --git a/spec/mspec/spec/matchers/signed_zero_spec.rb b/spec/mspec/spec/matchers/signed_zero_spec.rb
new file mode 100644
index 0000000000..9c5c50c602
--- /dev/null
+++ b/spec/mspec/spec/matchers/signed_zero_spec.rb
@@ -0,0 +1,32 @@
+require 'spec_helper'
+require 'mspec/expectations/expectations'
+require 'mspec/matchers'
+
+describe SignedZeroMatcher do
+  it "matches when actual is zero and has the correct sign" do
+    SignedZeroMatcher.new(1).matches?(0.0).should == true
+    SignedZeroMatcher.new(-1).matches?(-0.0).should == true
+  end
+
+  it "does not match when actual is non-zero" do
+    SignedZeroMatcher.new(1).matches?(1.0).should == false
+    SignedZeroMatcher.new(-1).matches?(-1.0).should == false
+  end
+
+  it "does not match when actual is zero but has the incorrect sign" do
+    SignedZeroMatcher.new(1).matches?(-0.0).should == false
+    SignedZeroMatcher.new(-1).matches?(0.0).should == false
+  end
+
+  it "provides a useful failure message" do
+    matcher = SignedZeroMatcher.new(-1)
+    matcher.matches?(0.0)
+    matcher.failure_message.should == ["Expected 0.0", "to be -0.0"]
+  end
+
+  it "provides a useful negative failure message" do
+    matcher = SignedZeroMatcher.new(-1)
+    matcher.matches?(-0.0)
+    matcher.negative_failure_message.should == ["Expected -0.0", "not to be -0.0"]
+  end
+end