1 files changed, 105 insertions, 0 deletions
diff --git a/spec/rubyspec/core/kernel/instance_variable_get_spec.rb b/spec/rubyspec/core/kernel/instance_variable_get_spec.rb
new file mode 100644
index 0000000000..0c564f11b6
--- /dev/null
+++ b/spec/rubyspec/core/kernel/instance_variable_get_spec.rb
@@ -0,0 +1,105 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+
+describe "Kernel#instance_variable_get" do
+  before :each do
+    @obj = Object.new
+    @obj.instance_variable_set("@test", :test)
+  end
+
+  it "tries to convert the passed argument to a String using #to_str" do
+    obj = mock("to_str")
+    obj.should_receive(:to_str).and_return("@test")
+    @obj.instance_variable_get(obj)
+  end
+
+  it "returns the value of the passed instance variable that is referred to by the conversion result" do
+    obj = mock("to_str")
+    obj.stub!(:to_str).and_return("@test")
+    @obj.instance_variable_get(obj).should == :test
+  end
+
+  it "returns nil when the referred instance variable does not exist" do
+    @obj.instance_variable_get(:@does_not_exist).should be_nil
+  end
+
+  it "raises a TypeError when the passed argument does not respond to #to_str" do
+    lambda { @obj.instance_variable_get(Object.new) }.should raise_error(TypeError)
+  end
+
+  it "raises a TypeError when the passed argument can't be converted to a String" do
+    obj = mock("to_str")
+    obj.stub!(:to_str).and_return(123)
+    lambda { @obj.instance_variable_get(obj) }.should raise_error(TypeError)
+  end
+
+  it "raises a NameError when the conversion result does not start with an '@'" do
+    obj = mock("to_str")
+    obj.stub!(:to_str).and_return("test")
+    lambda { @obj.instance_variable_get(obj) }.should raise_error(NameError)
+  end
+
+  it "raises a NameError when passed just '@'" do
+    obj = mock("to_str")
+    obj.stub!(:to_str).and_return('@')
+    lambda { @obj.instance_variable_get(obj) }.should raise_error(NameError)
+  end
+end
+
+describe "Kernel#instance_variable_get when passed Symbol" do
+  before :each do
+    @obj = Object.new
+    @obj.instance_variable_set("@test", :test)
+  end
+
+  it "returns the value of the instance variable that is referred to by the passed Symbol" do
+    @obj.instance_variable_get(:@test).should == :test
+  end
+
+  it "raises a NameError when passed :@ as an instance variable name" do
+    lambda { @obj.instance_variable_get(:"@") }.should raise_error(NameError)
+  end
+
+  it "raises a NameError when the passed Symbol does not start with an '@'" do
+    lambda { @obj.instance_variable_get(:test) }.should raise_error(NameError)
+  end
+
+  it "raises a NameError when the passed Symbol is an invalid instance variable name" do
+    lambda { @obj.instance_variable_get(:"@0") }.should raise_error(NameError)
+  end
+end
+
+describe "Kernel#instance_variable_get when passed String" do
+  before :each do
+    @obj = Object.new
+    @obj.instance_variable_set("@test", :test)
+  end
+
+  it "returns the value of the instance variable that is referred to by the passed String" do
+    @obj.instance_variable_get("@test").should == :test
+  end
+
+  it "raises a NameError when the passed String does not start with an '@'" do
+    lambda { @obj.instance_variable_get("test") }.should raise_error(NameError)
+  end
+
+  it "raises a NameError when the passed String is an invalid instance variable name" do
+    lambda { @obj.instance_variable_get("@0") }.should raise_error(NameError)
+  end
+
+  it "raises a NameError when passed '@' as an instance variable name" do
+    lambda { @obj.instance_variable_get("@") }.should raise_error(NameError)
+  end
+end
+
+describe "Kernel#instance_variable_get when passed Fixnum" do
+  before :each do
+    @obj = Object.new
+    @obj.instance_variable_set("@test", :test)
+  end
+
+  it "raises a TypeError" do
+    lambda { @obj.instance_variable_get(10) }.should raise_error(TypeError)
+    lambda { @obj.instance_variable_get(-10) }.should raise_error(TypeError)
+  end
+end