1 files changed, 21 insertions, 3 deletions
diff --git a/spec/ruby/core/string/rindex_spec.rb b/spec/ruby/core/string/rindex_spec.rb
index 7a6af0c9d0..88ce733583 100644
--- a/spec/ruby/core/string/rindex_spec.rb
+++ b/spec/ruby/core/string/rindex_spec.rb
@@ -1,16 +1,19 @@
 # -*- encoding: utf-8 -*-
 require_relative '../../spec_helper'
 require_relative 'fixtures/classes'
-require_relative 'fixtures/utf-8-encoding'
 
 describe "String#rindex with object" do
-  it "raises a TypeError if obj isn't a String, Integer or Regexp" do
+  it "raises a TypeError if obj isn't a String or Regexp" do
     not_supported_on :opal do
       -> { "hello".rindex(:sym) }.should raise_error(TypeError)
     end
     -> { "hello".rindex(mock('x')) }.should raise_error(TypeError)
   end
 
+  it "raises a TypeError if obj is an Integer" do
+    -> { "hello".rindex(42) }.should raise_error(TypeError)
+  end
+
   it "doesn't try to convert obj to an integer via to_int" do
     obj = mock('x')
     obj.should_not_receive(:to_int)
@@ -192,6 +195,21 @@ describe "String#rindex with String" do
   it "raises a TypeError when given offset is nil" do
     -> { "str".rindex("st", nil) }.should raise_error(TypeError)
   end
+
+  it "handles a substring in a superset encoding" do
+    'abc'.dup.force_encoding(Encoding::US_ASCII).rindex('é').should == nil
+  end
+
+  it "handles a substring in a subset encoding" do
+    'été'.rindex('t'.dup.force_encoding(Encoding::US_ASCII)).should == 1
+  end
+
+  it "raises an Encoding::CompatibilityError if the encodings are incompatible" do
+    str = 'abc'.dup.force_encoding("ISO-2022-JP")
+    pattern = 'b'.dup.force_encoding("EUC-JP")
+
+    -> { str.rindex(pattern) }.should raise_error(Encoding::CompatibilityError, "incompatible character encodings: ISO-2022-JP and EUC-JP")
+  end
 end
 
 describe "String#rindex with Regexp" do
@@ -361,6 +379,6 @@ describe "String#rindex with Regexp" do
     re = Regexp.new "れ".encode(Encoding::EUC_JP)
     -> do
       "あれ".rindex re
-    end.should raise_error(Encoding::CompatibilityError)
+    end.should raise_error(Encoding::CompatibilityError, "incompatible encoding regexp match (EUC-JP regexp with UTF-8 string)")
   end
 end