Clean up various use of escape/unescape functions for URL generation (#6334)

* Use PathUnescape instead of QueryUnescape when working with branch names

Currently branch names with a '+' fail in certain situations because
QueryUnescape replaces the + character with a blank space.

Using PathUnescape should be better since it is defined as:

// PathUnescape is identical to QueryUnescape except that it does not
// unescape '+' to ' ' (space).

Fixes #6333

* Change error to match new function name

* Add new util function PathEscapeSegments

This function simply runs PathEscape on each segment of a path without
touching the forward slash itself. We want to use this instead of
PathEscape/QueryEscape in most cases because a forward slash is a valid name for a
branch etc... and we don't want that escaped in a URL.

Putting this in new file url.go and also moving a couple similar
functions into that file as well.

* Use EscapePathSegments where appropriate

Replace various uses of EscapePath/EscapeQuery with new
EscapePathSegments. Also remove uncessary uses of various
escape/unescape functions when the text had already been escaped or was
not escaped.

* Reformat comment to make drone build happy

* Remove no longer used url library

* Requested code changes

1 files changed, 0 insertions, 40 deletions

diff --git a/modules/util/util.go b/modules/util/util.go
index b2067c8df6..4203b5eb51 100644
--- a/modules/util/util.go
+++ b/modules/util/util.go
@@ -5,12 +5,7 @@
 package util
 
 import (
-	"net/url"
-	"path"
 	"strings"
-
-	"code.gitea.io/gitea/modules/log"
-	"code.gitea.io/gitea/modules/setting"
 )
 
 // OptionalBool a boolean that can be "null"
@@ -56,41 +51,6 @@ func Max(a, b int) int {
 	return a
 }
 
-// URLJoin joins url components, like path.Join, but preserving contents
-func URLJoin(base string, elems ...string) string {
-	if !strings.HasSuffix(base, "/") {
-		base += "/"
-	}
-	baseURL, err := url.Parse(base)
-	if err != nil {
-		log.Error(4, "URLJoin: Invalid base URL %s", base)
-		return ""
-	}
-	joinedPath := path.Join(elems...)
-	argURL, err := url.Parse(joinedPath)
-	if err != nil {
-		log.Error(4, "URLJoin: Invalid arg %s", joinedPath)
-		return ""
-	}
-	joinedURL := baseURL.ResolveReference(argURL).String()
-	if !baseURL.IsAbs() && !strings.HasPrefix(base, "/") {
-		return joinedURL[1:] // Removing leading '/' if needed
-	}
-	return joinedURL
-}
-
-// IsExternalURL checks if rawURL points to an external URL like http://example.com
-func IsExternalURL(rawURL string) bool {
-	parsed, err := url.Parse(rawURL)
-	if err != nil {
-		return true
-	}
-	if len(parsed.Host) != 0 && strings.Replace(parsed.Host, "www.", "", 1) != strings.Replace(setting.Domain, "www.", "", 1) {
-		return true
-	}
-	return false
-}
-
 // Min min of two ints
 func Min(a, b int) int {
 	if a > b {