1 files changed, 31 insertions, 0 deletions
diff --git a/spec/ruby/core/integer/sqrt_spec.rb b/spec/ruby/core/integer/sqrt_spec.rb
new file mode 100644
index 0000000000..4149ca2cc9
--- /dev/null
+++ b/spec/ruby/core/integer/sqrt_spec.rb
@@ -0,0 +1,31 @@
+require_relative '../../spec_helper'
+
+describe "Integer.sqrt" do
+  it "returns an integer" do
+    Integer.sqrt(10).should be_kind_of(Integer)
+  end
+
+  it "returns the integer square root of the argument" do
+    Integer.sqrt(0).should == 0
+    Integer.sqrt(1).should == 1
+    Integer.sqrt(24).should == 4
+    Integer.sqrt(25).should == 5
+    Integer.sqrt(10**400).should == 10**200
+  end
+
+  it "raises a Math::DomainError if the argument is negative" do
+    -> { Integer.sqrt(-4) }.should raise_error(Math::DomainError)
+  end
+
+  it "accepts any argument that can be coerced to Integer" do
+    Integer.sqrt(10.0).should == 3
+  end
+
+  it "converts the argument with #to_int" do
+    Integer.sqrt(mock_int(10)).should == 3
+  end
+
+  it "raises a TypeError if the argument cannot be coerced to Integer" do
+    -> { Integer.sqrt("test") }.should raise_error(TypeError)
+  end
+end