1 files changed, 65 insertions, 0 deletions
diff --git a/spec/ruby/core/bignum/coerce_spec.rb b/spec/ruby/core/bignum/coerce_spec.rb
new file mode 100644
index 0000000000..40decaf51a
--- /dev/null
+++ b/spec/ruby/core/bignum/coerce_spec.rb
@@ -0,0 +1,65 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe "Bignum#coerce" do
+  it "coerces other to a Bignum and returns [other, self] when passed a Fixnum" do
+    a = bignum_value
+    ary = a.coerce(2)
+
+    ary[0].should be_kind_of(Bignum)
+    ary[1].should be_kind_of(Bignum)
+    ary.should == [2, a]
+  end
+
+  it "returns [other, self] when passed a Bignum" do
+    a = bignum_value
+    b = bignum_value
+    ary = a.coerce(b)
+
+    ary[0].should be_kind_of(Bignum)
+    ary[1].should be_kind_of(Bignum)
+    ary.should == [b, a]
+  end
+
+  it "raises a TypeError when not passed a Fixnum or Bignum" do
+    a = bignum_value
+
+    lambda { a.coerce(nil)         }.should raise_error(TypeError)
+    lambda { a.coerce(mock('str')) }.should raise_error(TypeError)
+    lambda { a.coerce(1..4)        }.should raise_error(TypeError)
+    lambda { a.coerce(:test)       }.should raise_error(TypeError)
+  end
+
+  ruby_version_is ""..."2.4" do
+    it "raises a TypeError when passed a String" do
+      a = bignum_value
+      lambda { a.coerce("123") }.should raise_error(TypeError)
+    end
+
+    it "raises a TypeError when passed a Float" do
+      a = bignum_value
+      lambda { a.coerce(12.3) }.should raise_error(TypeError)
+    end
+  end
+
+  ruby_version_is "2.4" do
+    it "coerces both values to Floats and returns [other, self] when passed a Float" do
+      a = bignum_value
+      a.coerce(1.2).should == [1.2, a.to_f]
+    end
+
+    it "coerces both values to Floats and returns [other, self] when passed a String" do
+      a = bignum_value
+      a.coerce("123").should == [123.0, a.to_f]
+    end
+
+    it "calls #to_f to coerce other to a Float" do
+      b = mock("bignum value")
+      b.should_receive(:to_f).and_return(1.2)
+
+      a = bignum_value
+      ary = a.coerce(b)
+
+      ary.should == [1.2, a.to_f]
+    end
+  end
+end