1 files changed, 43 insertions, 7 deletions
diff --git a/spec/ruby/core/env/replace_spec.rb b/spec/ruby/core/env/replace_spec.rb
index 8837deea4a..9fc67643d1 100644
--- a/spec/ruby/core/env/replace_spec.rb
+++ b/spec/ruby/core/env/replace_spec.rb
@@ -1,15 +1,51 @@
 require_relative '../../spec_helper'
 
 describe "ENV.replace" do
+  before :each do
+    @orig = ENV.to_hash
+    ENV.delete("foo")
+  end
+
+  after :each do
+    ENV.replace(@orig)
+  end
 
   it "replaces ENV with a Hash" do
-    ENV["foo"] = "bar"
-    e = ENV.reject { |k, v| k == "foo" }
-    e["baz"] = "bam"
-    ENV.replace e
-    ENV["foo"].should == nil
-    ENV["baz"].should == "bam"
-    ENV.delete "baz"
+    ENV.replace("foo" => "0", "bar" => "1").should equal(ENV)
+    ENV.size.should == 2
+    ENV["foo"].should == "0"
+    ENV["bar"].should == "1"
+  end
+
+  it "raises TypeError if the argument is not a Hash" do
+    -> { ENV.replace(Object.new) }.should raise_error(TypeError, "no implicit conversion of Object into Hash")
+    ENV.to_hash.should == @orig
+  end
+
+  it "raises TypeError if a key is not a String" do
+    -> { ENV.replace(Object.new => "0") }.should raise_error(TypeError, "no implicit conversion of Object into String")
+    ENV.to_hash.should == @orig
+  end
+
+  it "raises TypeError if a value is not a String" do
+    -> { ENV.replace("foo" => Object.new) }.should raise_error(TypeError, "no implicit conversion of Object into String")
+    ENV.to_hash.should == @orig
+  end
+
+  it "raises Errno::EINVAL when the key contains the '=' character" do
+    -> { ENV.replace("foo=" =>"bar") }.should raise_error(Errno::EINVAL)
+  end
+
+  it "raises Errno::EINVAL when the key is an empty string" do
+    -> { ENV.replace("" => "bar") }.should raise_error(Errno::EINVAL)
+  end
+
+  it "does not accept good data preceding an error" do
+    -> { ENV.replace("foo" => "1", Object.new => Object.new) }.should raise_error(TypeError, "no implicit conversion of Object into String")
   end
 
+  it "does not accept good data following an error" do
+    -> { ENV.replace(Object.new => Object.new, "foo" => "0") }.should raise_error(TypeError, "no implicit conversion of Object into String")
+    ENV.to_hash.should == @orig
+  end
 end