1 files changed, 180 insertions, 0 deletions
diff --git a/spec/ruby/core/basicobject/instance_eval_spec.rb b/spec/ruby/core/basicobject/instance_eval_spec.rb
new file mode 100644
index 0000000000..3898e96b8b
--- /dev/null
+++ b/spec/ruby/core/basicobject/instance_eval_spec.rb
@@ -0,0 +1,180 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+
+describe "BasicObject#instance_eval" do
+  before :each do
+    ScratchPad.clear
+  end
+
+  it "is a public instance method" do
+    BasicObject.should have_public_instance_method(:instance_eval)
+  end
+
+  it "sets self to the receiver in the context of the passed block" do
+    a = BasicObject.new
+    a.instance_eval { self }.equal?(a).should be_true
+  end
+
+  it "evaluates strings" do
+    a = BasicObject.new
+    a.instance_eval('self').equal?(a).should be_true
+  end
+
+  it "expects a block with no arguments" do
+    lambda { "hola".instance_eval }.should raise_error(ArgumentError)
+  end
+
+  it "takes no arguments with a block" do
+    lambda { "hola".instance_eval(4, 5) {|a,b| a + b } }.should raise_error(ArgumentError)
+  end
+
+  it "yields the object to the block" do
+    "hola".instance_eval {|o| ScratchPad.record o }
+    ScratchPad.recorded.should == "hola"
+  end
+
+  it "returns the result of the block" do
+    "hola".instance_eval { :result }.should == :result
+  end
+
+  it "only binds the eval to the receiver" do
+    f = Object.new
+    f.instance_eval do
+      def foo
+        1
+      end
+    end
+    f.foo.should == 1
+    lambda { Object.new.foo }.should raise_error(NoMethodError)
+  end
+
+  it "preserves self in the original block when passed a block argument" do
+    prc = proc { self }
+
+    old_self = prc.call
+
+    new_self = Object.new
+    new_self.instance_eval(&prc).should == new_self
+
+    prc.call.should == old_self
+  end
+
+  # TODO: This should probably be replaced with a "should behave like" that uses
+  # the many scoping/binding specs from kernel/eval_spec, since most of those
+  # behaviors are the same for instance_eval. See also module_eval/class_eval.
+
+  it "binds self to the receiver" do
+    s = "hola"
+    (s == s.instance_eval { self }).should be_true
+    o = mock('o')
+    (o == o.instance_eval("self")).should be_true
+  end
+
+  it "executes in the context of the receiver" do
+    "Ruby-fu".instance_eval { size }.should == 7
+    "hola".instance_eval("size").should == 4
+    Object.class_eval { "hola".instance_eval("to_s") }.should == "hola"
+    Object.class_eval { "Ruby-fu".instance_eval{ to_s } }.should == "Ruby-fu"
+
+  end
+
+  it "has access to receiver's instance variables" do
+    BasicObjectSpecs::IVars.new.instance_eval { @secret }.should == 99
+    BasicObjectSpecs::IVars.new.instance_eval("@secret").should == 99
+  end
+
+  it "treats block-local variables as local to the block" do
+    prc = instance_eval <<-CODE
+      proc do |x, prc|
+        if x
+          n = 2
+        else
+          n = 1
+          prc.call(true, prc)
+          n
+        end
+      end
+    CODE
+
+    prc.call(false, prc).should == 1
+  end
+
+  it "sets class variables in the receiver" do
+    BasicObjectSpecs::InstEvalCVar.class_variables.should include(:@@count)
+    BasicObjectSpecs::InstEvalCVar.send(:class_variable_get, :@@count).should == 2
+  end
+
+  it "makes the receiver metaclass the scoped class when used with a string" do
+    obj = Object.new
+    obj.instance_eval %{
+      class B; end
+      B
+    }
+    obj.singleton_class.const_get(:B).should be_an_instance_of(Class)
+  end
+
+  it "gets constants in the receiver if a string given" do
+    BasicObjectSpecs::InstEvalOuter::Inner::X_BY_STR.should == 2
+  end
+
+  it "doesn't get constants in the receiver if a block given" do
+    BasicObjectSpecs::InstEvalOuter::Inner::X_BY_BLOCK.should be_nil
+  end
+
+  it "raises a TypeError when defining methods on an immediate" do
+    lambda do
+      1.instance_eval { def foo; end }
+    end.should raise_error(TypeError)
+    lambda do
+      :foo.instance_eval { def foo; end }
+    end.should raise_error(TypeError)
+  end
+
+quarantine! do # Not clean, leaves cvars lying around to break other specs
+  it "scopes class var accesses in the caller when called on a Fixnum" do
+    # Fixnum can take instance vars
+    Fixnum.class_eval "@@__tmp_instance_eval_spec = 1"
+    (defined? @@__tmp_instance_eval_spec).should be_nil
+
+    @@__tmp_instance_eval_spec = 2
+    1.instance_eval { @@__tmp_instance_eval_spec }.should == 2
+    Fixnum.__send__(:remove_class_variable, :@@__tmp_instance_eval_spec)
+  end
+end
+
+  it "raises a TypeError when defining methods on numerics" do
+    lambda do
+      (1.0).instance_eval { def foo; end }
+    end.should raise_error(TypeError)
+    lambda do
+      (1 << 64).instance_eval { def foo; end }
+    end.should raise_error(TypeError)
+  end
+
+  it "evaluates procs originating from methods" do
+    def meth(arg); arg; end
+
+    m = method(:meth)
+    obj = Object.new
+
+    obj.instance_eval(&m).should == obj
+  end
+
+  it "evaluates string with given filename and linenumber" do
+    err = begin
+      Object.new.instance_eval("raise", "a_file", 10)
+    rescue => e
+      e
+    end
+    err.backtrace.first.split(":")[0..1].should == ["a_file", "10"]
+  end
+
+  it "evaluates string with given filename and negative linenumber" do
+    err = begin
+      Object.new.instance_eval("\n\nraise\n", "b_file", -100)
+    rescue => e
+      e
+    end
+    err.backtrace.first.split(":")[0..1].should == ["b_file", "-98"]
+  end
+end