Use weighted algorithm for string matching when finding files in repo (#21370)

This PR is for:
* https://github.com/go-gitea/gitea/issues/20231

Now, when a user searches `word`, they always see `/{word}.txt` before
`/{w}e-g{o}t-{r}esult.{d}at`

Demo:

When searching "a", "a.ext" comes first. 

Then when searching "at", the longer matched "template" comes first.

<details>


![image](https://user-images.githubusercontent.com/2114189/194588738-3644d891-956f-40e4-b79b-b97d34265456.png)


![image](https://user-images.githubusercontent.com/2114189/194588797-9b124670-4e1e-4510-a170-780295ed89b8.png)

</details>

This PR also makes the frontend tests could import feature JS files by
introducing `jestSetup.js`

Co-authored-by: delvh <dev.lh@web.de>
Co-authored-by: silverwind <me@silverwind.io>

1 files changed, 0 insertions, 30 deletions

diff --git a/web_src/js/utils.js b/web_src/js/utils.js
index 8e8dc01be1..4020b7a7f4 100644
--- a/web_src/js/utils.js
+++ b/web_src/js/utils.js
@@ -59,36 +59,6 @@ export function parseIssueHref(href) {
   return {owner, repo, type, index};
 }
 
-// return the sub-match result as an array:  [unmatched, matched, unmatched, matched, ...]
-// res[even] is unmatched, res[odd] is matched, see unit tests for examples
-export function strSubMatch(full, sub) {
-  const res = [''];
-  let i = 0, j = 0;
-  const subLower = sub.toLowerCase(), fullLower = full.toLowerCase();
-  while (i < subLower.length && j < fullLower.length) {
-    if (subLower[i] === fullLower[j]) {
-      if (res.length % 2 !== 0) res.push('');
-      res[res.length - 1] += full[j];
-      j++;
-      i++;
-    } else {
-      if (res.length % 2 === 0) res.push('');
-      res[res.length - 1] += full[j];
-      j++;
-    }
-  }
-  if (i !== sub.length) {
-    // if the sub string doesn't match the full, only return the full as unmatched.
-    return [full];
-  }
-  if (j < full.length) {
-    // append remaining chars from full to result as unmatched
-    if (res.length % 2 === 0) res.push('');
-    res[res.length - 1] += full.substring(j);
-  }
-  return res;
-}
-
 // pretty-print a number using locale-specific separators, e.g. 1200 -> 1,200
 export function prettyNumber(num, locale = 'en-US') {
   if (typeof num !== 'number') return '';