Fix gitgraph branch continues after merge (go-gitea#12044)

* Fix gitgraph branch continues after merge

After fixing the initial problem in go-gitea#11981 another
problem has come to light...

Fix go-gitea#11981 (part 2)

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Update web_src/js/vendor/gitgraph.js

* Apply suggestions from code review

Co-authored-by: silverwind <me@silverwind.io>

Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>

web_src/js/vendor/gitgraph.js

@@ -372,6 +372,10 @@ export default function gitGraph(canvas, rawGraphList, config) {
  inlineIntersect = false;
  }
 
+ if (colomn === '|' && currentRow[colomnIndex - 1] && currentRow[colomnIndex - 1] === '\\') {
+ flows.splice(colomnIndex, 0, genNewFlow());
+ }
+
  color = flows[colomnIndex].color;
 
  switch (colomn) {
@@ -387,6 +391,9 @@ export default function gitGraph(canvas, rawGraphList, config) {
  break;
 
  case '|':
+ if (prevColomn && prevColomn === '\\') {
+ x += config.unitSize;
+ }
  drawLineUp(x, y, color);
  break;