Replace clipboard.js with async clipboard api (go-gitea#15899)

Use async clipboard api [1] over this dependency, saving around 10kB
bundle size before minify while delivering the same functionality.

The issue comment button works but does not have a popup indication. We
could add some toast-style notifications in the future to fix that but I
think it's out of scope of this PR.

[1] https://developer.mozilla.org/en-US/docs/Web/API/Clipboard/writeText

package.json

@@ -9,7 +9,6 @@
     "@claviska/jquery-minicolors": "2.3.5",
     "@primer/octicons": "13.0.0",
     "add-asset-webpack-plugin": "2.0.1",
-    "clipboard": "2.0.8",
     "codemirror": "5.61.0",
     "css-loader": "5.2.4",
     "dropzone": "5.9.2",

templates/repo/clone_buttons.tmpl

@@ -14,7 +14,7 @@
 	<input id="repo-clone-url" value="{{if $.PageIsWiki}}{{$.WikiCloneLink.SSH}}{{else}}{{$.CloneLink.SSH}}{{end}}" readonly>
 {{end}}
 {{if or (not $.DisableHTTP) (and (not $.DisableSSH) (or $.IsSigned $.ExposeAnonSSH))}}
-	<button class="ui basic icon button poping up clipboard" id="clipboard-btn" data-original="{{.i18n.Tr "repo.copy_link"}}" data-success="{{.i18n.Tr "repo.copy_link_success"}}" data-error="{{.i18n.Tr "repo.copy_link_error"}}" data-content="{{.i18n.Tr "repo.copy_link"}}" data-variation="inverted tiny" data-clipboard-target="#repo-clone-url">
+	<button class="ui basic icon button poping up" id="clipboard-btn" data-original="{{.i18n.Tr "repo.copy_link"}}" data-success="{{.i18n.Tr "repo.copy_link_success"}}" data-error="{{.i18n.Tr "repo.copy_link_error"}}" data-content="{{.i18n.Tr "repo.copy_link"}}" data-variation="inverted tiny" data-clipboard-target="#repo-clone-url">
 		{{svg "octicon-clippy"}}
 	</button>
 {{end}}

templates/repo/issue/view_content/context_menu.tmpl

@@ -10,7 +10,7 @@
 		{{ else }}
 			{{ $referenceUrl = Printf "%s%s/pulls/%d/files#%s" AppUrl .ctx.Repository.FullName .ctx.Issue.Index .item.HashTag }}
 		{{ end }}
-		<div class="item context clipboard" data-clipboard-text="{{$referenceUrl}}">{{.ctx.i18n.Tr "repo.issues.context.copy_link"}}</div>
+		<div class="item context" data-clipboard-text="{{$referenceUrl}}">{{.ctx.i18n.Tr "repo.issues.context.copy_link"}}</div>
 		<div class="item context quote-reply {{if .diff}}quote-reply-diff{{end}}" data-target="{{.item.ID}}">{{.ctx.i18n.Tr "repo.issues.context.quote_reply"}}</div>
 		{{if not .ctx.UnitIssuesGlobalDisabled}}
 			<div class="item context reference-issue" data-target="{{.item.ID}}" data-modal="#reference-issue-modal" data-poster="{{.item.Poster.GetDisplayName}}" data-reference="{{$referenceUrl}}">{{.ctx.i18n.Tr "repo.issues.context.reference_issue"}}</div>

web_src/js/features/clipboard.js

@@ -1,22 +1,38 @@
-export default async function initClipboard() {
-  const els = document.querySelectorAll('.clipboard');
-  if (!els || !els.length) return;
+const selector = '[data-clipboard-target], [data-clipboard-text]';
 
-  const {default: ClipboardJS} = await import(/* webpackChunkName: "clipboard" */'clipboard');
+// TODO: replace these with toast-style notifications
+function onSuccess(btn) {
+  if (!btn.dataset.content) return;
+  $(btn).popup('destroy');
+  btn.dataset.content = btn.dataset.success;
+  $(btn).popup('show');
+  btn.dataset.content = btn.dataset.original;
+}
+function onError(btn) {
+  if (!btn.dataset.content) return;
+  $(btn).popup('destroy');
+  btn.dataset.content = btn.dataset.error;
+  $(btn).popup('show');
+  btn.dataset.content = btn.dataset.original;
+}
 
-  const clipboard = new ClipboardJS(els);
-  clipboard.on('success', (e) => {
-    e.clearSelection();
-    $(e.trigger).popup('destroy');
-    e.trigger.dataset.content = e.trigger.dataset.success;
-    $(e.trigger).popup('show');
-    e.trigger.dataset.content = e.trigger.dataset.original;
-  });
+export default async function initClipboard() {
+  for (const btn of document.querySelectorAll(selector) || []) {
+    btn.addEventListener('click', async () => {
+      let text;
+      if (btn.dataset.clipboardText) {
+        text = btn.dataset.clipboardText;
+      } else if (btn.dataset.clipboardTarget) {
+        text = document.querySelector(btn.dataset.clipboardTarget)?.value;
+      }
+      if (!text) return;
 
-  clipboard.on('error', (e) => {
-    $(e.trigger).popup('destroy');
-    e.trigger.dataset.content = e.trigger.dataset.error;
-    $(e.trigger).popup('show');
-    e.trigger.dataset.content = e.trigger.dataset.original;
-  });
+      try {
+        await navigator.clipboard.writeText(text);
+        onSuccess(btn);
+      } catch {
+        onError(btn);
+      }
+    });
+  }
 }