From fc85699a9506c6f6376742ea92a9a549af2eba84 Mon Sep 17 00:00:00 2001
From: Larry Lv <larrylv1990@gmail.com>
Date: Sun, 26 Jul 2020 17:48:24 -0700
Subject: [PATCH] =?UTF-8?q?=F0=9F=A7=B9=20Refactor=20etag=20stale=20checki?=
 =?UTF-8?q?ng?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 ctx.go   | 10 +---------
 utils.go | 25 ++++++++++++++++---------
 2 files changed, 17 insertions(+), 18 deletions(-)

diff --git a/ctx.go b/ctx.go
index 07912ba5..6aa93fb0 100644
--- a/ctx.go
+++ b/ctx.go
@@ -449,15 +449,7 @@ func (ctx *Ctx) Fresh() bool {
 		if etag == "" {
 			return false
 		}
-		var etagStale = true
-		var matches = parseTokenList(getBytes(noneMatch))
-		for _, match := range matches {
-			if match == etag || match == "W/"+etag || "W/"+match == etag {
-				etagStale = false
-				break
-			}
-		}
-		if etagStale {
+		if isEtagStale(etag, getBytes(noneMatch)) {
 			return false
 		}
 
diff --git a/utils.go b/utils.go
index 121885d1..06bc0940 100644
--- a/utils.go
+++ b/utils.go
@@ -163,14 +163,14 @@ func getOffer(header string, offers ...string) string {
 	return ""
 }
 
-// Adapted from:
-// https://github.com/jshttp/fresh/blob/10e0471669dbbfbfd8de65bc6efac2ddd0bfa057/index.js#L110
-func parseTokenList(noneMatchBytes []byte) []string {
+func isEtagStale(etag string, noneMatchBytes []byte) bool {
 	var (
-		start int
-		end   int
-		list  []string
+		start   int
+		end     int
+		matches []string
 	)
+	// Adapted from:
+	// https://github.com/jshttp/fresh/blob/10e0471669dbbfbfd8de65bc6efac2ddd0bfa057/index.js#L110
 	for i := range noneMatchBytes {
 		switch noneMatchBytes[i] {
 		case 0x20:
@@ -179,7 +179,7 @@ func parseTokenList(noneMatchBytes []byte) []string {
 				end = i + 1
 			}
 		case 0x2c:
-			list = append(list, getString(noneMatchBytes[start:end]))
+			matches = append(matches, getString(noneMatchBytes[start:end]))
 			start = i + 1
 			end = i + 1
 		default:
@@ -187,8 +187,15 @@ func parseTokenList(noneMatchBytes []byte) []string {
 		}
 	}
 
-	list = append(list, getString(noneMatchBytes[start:end]))
-	return list
+	matches = append(matches, getString(noneMatchBytes[start:end]))
+
+	for _, match := range matches {
+		if match == etag || match == "W/"+etag || "W/"+match == etag {
+			return false
+		}
+	}
+
+	return true
 }
 
 func isIPv6(address string) bool {