From 52f8dcda43645a1e961243e46b557f39f6a2d616 Mon Sep 17 00:00:00 2001
From: mlpo <mlpo@mlpo.fr>
Date: Thu, 13 May 2021 11:31:23 +0200
Subject: [PATCH] Allow custom highlight mapping beyond file extensions
 (#15808)

Co-authored-by: Lauris BH <lauris@nix.lv>
---
 modules/highlight/highlight.go | 27 +++++++++++++++++----------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/modules/highlight/highlight.go b/modules/highlight/highlight.go
index 914ba8210..a46499691 100644
--- a/modules/highlight/highlight.go
+++ b/modules/highlight/highlight.go
@@ -16,6 +16,7 @@ import (
 	"code.gitea.io/gitea/modules/analyze"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
+	"github.com/alecthomas/chroma"
 	"github.com/alecthomas/chroma/formatters/html"
 	"github.com/alecthomas/chroma/lexers"
 	"github.com/alecthomas/chroma/styles"
@@ -66,14 +67,17 @@ func Code(fileName, code string) string {
 	htmlbuf := bytes.Buffer{}
 	htmlw := bufio.NewWriter(&htmlbuf)
 
+	var lexer chroma.Lexer
 	if val, ok := highlightMapping[filepath.Ext(fileName)]; ok {
-		//change file name to one with mapped extension so we look that up instead
-		fileName = "mapped." + val
+		//use mapped value to find lexer
+		lexer = lexers.Get(val)
 	}
 
-	lexer := lexers.Match(fileName)
 	if lexer == nil {
-		lexer = lexers.Fallback
+		lexer = lexers.Match(fileName)
+		if lexer == nil {
+			lexer = lexers.Fallback
+		}
 	}
 
 	iterator, err := lexer.Tokenise(nil, string(code))
@@ -114,17 +118,20 @@ func File(numLines int, fileName string, code []byte) map[int]string {
 	htmlbuf := bytes.Buffer{}
 	htmlw := bufio.NewWriter(&htmlbuf)
 
+	var lexer chroma.Lexer
 	if val, ok := highlightMapping[filepath.Ext(fileName)]; ok {
-		fileName = "test." + val
+		lexer = lexers.Get(val)
 	}
 
-	language := analyze.GetCodeLanguage(fileName, code)
-
-	lexer := lexers.Get(language)
 	if lexer == nil {
-		lexer = lexers.Match(fileName)
+		language := analyze.GetCodeLanguage(fileName, code)
+
+		lexer = lexers.Get(language)
 		if lexer == nil {
-			lexer = lexers.Fallback
+			lexer = lexers.Match(fileName)
+			if lexer == nil {
+				lexer = lexers.Fallback
+			}
 		}
 	}