From 4646a330905d8195e2664e6142832ad118f7bb03 Mon Sep 17 00:00:00 2001
From: Samuel Tan <samueltan@google.com>
Date: Fri, 14 Apr 2017 09:50:00 -0700
Subject: [PATCH] html/template: ensure that MIME type handling is case
 insensitive

Handle MIME types found in the type attribute of the script element
in a case insensitive way, as per Section 5.1 of RFC 2045.

Fixes #19968

Change-Id: Ie1416178c937dcf2c96bcec4191cebe7c3477af8
Reviewed-on: https://go-review.googlesource.com/40702
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
---
 src/html/template/escape_test.go | 5 +++++
 src/html/template/js.go          | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/html/template/escape_test.go b/src/html/template/escape_test.go
index 5dfb09b500..0a6a9e49c7 100644
--- a/src/html/template/escape_test.go
+++ b/src/html/template/escape_test.go
@@ -1399,6 +1399,11 @@ func TestEscapeText(t *testing.T) {
 			`<script type="text/template">`,
 			context{state: stateText},
 		},
+		// covering issue 19968
+		{
+			`<script type="TEXT/JAVASCRIPT">`,
+			context{state: stateJS, element: elementScript},
+		},
 		{
 			`<script type="notjs">`,
 			context{state: stateText},
diff --git a/src/html/template/js.go b/src/html/template/js.go
index 6434fa3be6..239395f8d3 100644
--- a/src/html/template/js.go
+++ b/src/html/template/js.go
@@ -372,7 +372,7 @@ func isJSType(mimeType string) bool {
 	//   https://tools.ietf.org/html/rfc7231#section-3.1.1
 	//   https://tools.ietf.org/html/rfc4329#section-3
 	//   https://www.ietf.org/rfc/rfc4627.txt
-
+	mimeType = strings.ToLower(mimeType)
 	// discard parameters
 	if i := strings.Index(mimeType, ";"); i >= 0 {
 		mimeType = mimeType[:i]
-- 
2.50.0