1 files changed, 61 insertions, 0 deletions
diff --git a/spec/ruby/language/source_encoding_spec.rb b/spec/ruby/language/source_encoding_spec.rb
new file mode 100644
index 0000000000..7135bc0a70
--- /dev/null
+++ b/spec/ruby/language/source_encoding_spec.rb
@@ -0,0 +1,61 @@
+require_relative '../spec_helper'
+
+describe "Source files" do
+
+  describe "encoded in UTF-8 without a BOM" do
+    it "can be parsed" do
+      ruby_exe(fixture(__FILE__, "utf8-nobom.rb"), args: "2>&1").should == "hello\n"
+    end
+  end
+
+  describe "encoded in UTF-8 with a BOM" do
+    it "can be parsed" do
+      ruby_exe(fixture(__FILE__, "utf8-bom.rb"), args: "2>&1").should == "hello\n"
+    end
+  end
+
+  describe "encoded in UTF-16 LE without a BOM" do
+    it "are parsed as empty because they contain a NUL byte before the encoding comment" do
+      ruby_exe(fixture(__FILE__, "utf16-le-nobom.rb"), args: "2>&1").should == ""
+    end
+  end
+
+  describe "encoded in UTF-16 LE with a BOM" do
+    it "are invalid because they contain an invalid UTF-8 sequence before the encoding comment" do
+      bom = "\xFF\xFE".b
+      source = "# encoding: utf-16le\nputs 'hello'\n"
+      source = bom + source.bytes.zip([0]*source.bytesize).flatten.pack('C*')
+      path = tmp("utf16-le-bom.rb")
+
+      touch(path, "wb") { |f| f.write source }
+      begin
+        ruby_exe(path, args: "2>&1", exit_status: 1).should =~ /invalid multibyte char/
+      ensure
+        rm_r path
+      end
+    end
+  end
+
+  describe "encoded in UTF-16 BE without a BOM" do
+    it "are parsed as empty because they contain a NUL byte before the encoding comment" do
+      ruby_exe(fixture(__FILE__, "utf16-be-nobom.rb"), args: "2>&1").should == ""
+    end
+  end
+
+  describe "encoded in UTF-16 BE with a BOM" do
+    it "are invalid because they contain an invalid UTF-8 sequence before the encoding comment" do
+      bom = "\xFE\xFF".b
+      source = "# encoding: utf-16be\nputs 'hello'\n"
+      source = bom + ([0]*source.bytesize).zip(source.bytes).flatten.pack('C*')
+      path = tmp("utf16-be-bom.rb")
+
+      touch(path, "wb") { |f| f.write source }
+      begin
+        ruby_exe(path, args: "2>&1", exit_status: 1).should =~ /invalid multibyte char/
+      ensure
+        rm_r path
+      end
+    end
+  end
+
+end