From 83d4565b227508e25bd1e93d2155d167be51dc74 Mon Sep 17 00:00:00 2001
From: Robert Krimen <robertkrimen@gmail.com>
Date: Thu, 2 May 2013 20:23:06 +0200
Subject: [PATCH] Make decodeURI correspond to the 15.1.3.1 algorithm and
 decodeURIComponent ito 15.1.3.2

---
 builtin.go     | 31 +++++++++++++++++++++++++++----
 global.go      |  4 ++--
 global_test.go | 12 ++++++++++++
 3 files changed, 41 insertions(+), 6 deletions(-)

diff --git a/builtin.go b/builtin.go
index 775ad52..999d122 100644
--- a/builtin.go
+++ b/builtin.go
@@ -177,12 +177,35 @@ func builtinGlobal_encodeURIComponent(call FunctionCall) Value {
 	return _builtinGlobal_encodeURI(call, encodeURIComponent_Regexp)
 }
 
-func builtinGlobal_decodeURI_decodeURIComponent(call FunctionCall) Value {
-	value, err := url.QueryUnescape(toString(call.Argument(0)))
-	if err != nil {
+// 3B/2F/3F/3A/40/26/3D/2B/24/2C/23
+var decodeURI_guard = regexp.MustCompile(`(?i)(?:%)(3B|2F|3F|3A|40|26|3D|2B|24|2C|23)`)
+
+func _decodeURI(input string, reserve bool) (string, bool) {
+	if reserve {
+		input = decodeURI_guard.ReplaceAllString(input, "%25$1")
+	}
+	input = strings.Replace(input, "+", "%2B", -1) // Ugly hack to make QueryUnescape work with our use case
+	output, err := url.QueryUnescape(input)
+	if err != nil || !utf8.ValidString(output) {
+		return "", true
+	}
+	return output, false
+}
+
+func builtinGlobal_decodeURI(call FunctionCall) Value {
+	output, err := _decodeURI(toString(call.Argument(0)), true)
+	if err {
 		panic(newURIError("URI malformed"))
 	}
-	return toValue(value)
+	return toValue(output)
+}
+
+func builtinGlobal_decodeURIComponent(call FunctionCall) Value {
+	output, err := _decodeURI(toString(call.Argument(0)), false)
+	if err {
+		panic(newURIError("URI malformed"))
+	}
+	return toValue(output)
 }
 
 // escape/unescape
diff --git a/global.go b/global.go
index 8d6b0b8..dac5275 100644
--- a/global.go
+++ b/global.go
@@ -706,8 +706,8 @@ func newContext() *_runtime {
 		"parseFloat", -1, builtinGlobal_parseFloat,
 		"isNaN", -1, builtinGlobal_isNaN,
 		"isFinite", -1, builtinGlobal_isFinite,
-		"decodeURI", builtinGlobal_decodeURI_decodeURIComponent,
-		"decodeURIComponent", builtinGlobal_decodeURI_decodeURIComponent,
+		"decodeURI", -1, builtinGlobal_decodeURI,
+		"decodeURIComponent", -1, builtinGlobal_decodeURIComponent,
 		"encodeURI", builtinGlobal_encodeURI,
 		"encodeURIComponent", builtinGlobal_encodeURIComponent,
 		"escape", builtinGlobal_escape,
diff --git a/global_test.go b/global_test.go
index a97c8eb..4eb66ad 100644
--- a/global_test.go
+++ b/global_test.go
@@ -2,6 +2,8 @@ package otto
 
 import (
 	. "./terst"
+	"fmt"
+	"strings"
 	"testing"
 )
 
@@ -190,6 +192,13 @@ func Test_decodeURI(t *testing.T) {
 	test(`decodeURI(encodeURI("http://example.com/ Nothing happens."))`, "http://example.com/ Nothing happens.")
 	test(`decodeURI(encodeURI("http://example.com/ _^#"))`, "http://example.com/ _^#")
 	test(`raise: decodeURI("http://example.com/ _^#%")`, "URIError: URI malformed")
+	test(`raise: decodeURI("%DF%7F")`, "URIError: URI malformed")
+	for _, check := range strings.Fields("+ %3B %2F %3F %3A %40 %26 %3D %2B %24 %2C %23") {
+		test(fmt.Sprintf(`decodeURI("%s")`, check), check)
+	}
+
+	test(`decodeURI.length === 1`, "true")
+	test(`decodeURI.prototype === undefined`, "true")
 }
 
 func Test_decodeURIComponent(t *testing.T) {
@@ -198,6 +207,9 @@ func Test_decodeURIComponent(t *testing.T) {
 	test := runTest()
 	test(`decodeURIComponent(encodeURI("http://example.com/ Nothing happens."))`, "http://example.com/ Nothing happens.")
 	test(`decodeURIComponent(encodeURI("http://example.com/ _^#"))`, "http://example.com/ _^#")
+
+	test(`decodeURIComponent.length === 1`, "true")
+	test(`decodeURIComponent.prototype === undefined`, "true")
 }
 
 func TestGlobal_skipEnumeration(t *testing.T) {