Add copy from parent to editing field buttons

Summary: The "copy from parent" action already exists in the commit info header, but it's not easily discoverable when editing individual fields. This adds an additional entrypoint for "copy from parent" directly in the editing field toolbar, making it more accessible during the commit message editing workflow.

Reviewed By: nsblake

Differential Revision: D93452994

fbshipit-source-id: c292fb1df980ca8e2899e201eda5d2279638628c

Author: babyleafy

addons/isl/src/CommitInfoView/CommitInfoField.tsx

@@ -129,6 +129,7 @@ export function CommitInfoField({
                 autoFocus={autofocus ?? false}
                 editedMessage={editedFieldContent}
                 setEditedField={setEditedField}
+                copyFromParent={copyFromParent}
               />
             )}
             {extra}

addons/isl/src/CommitInfoView/TextArea.tsx

@@ -7,7 +7,10 @@
 
 import type {ReactNode, RefObject} from 'react';
 
+import {Button} from 'isl-components/Button';
+import {Icon} from 'isl-components/Icon';
 import {TextArea} from 'isl-components/TextArea';
+import {Tooltip} from 'isl-components/Tooltip';
 import {useEffect, useRef} from 'react';
 import {InternalFieldName} from 'shared/constants';
 import {
@@ -30,12 +33,14 @@ export function CommitInfoTextArea({
   autoFocus,
   editedMessage,
   setEditedField,
+  copyFromParent,
 }: {
   kind: 'title' | 'textarea' | 'field';
   name: string;
   autoFocus: boolean;
   editedMessage: string;
   setEditedField: (fieldValue: string) => unknown;
+  copyFromParent?: () => void;
 }) {
   const ref = useRef<HTMLTextAreaElement>(null);
   useEffect(() => {
@@ -93,6 +98,7 @@ export function CommitInfoTextArea({
         fieldName={name}
         uploadFiles={supportsImageUpload ? uploadFiles : undefined}
         textAreaRef={ref}
+        copyFromParent={copyFromParent}
       />
     </div>
   );
@@ -110,10 +116,12 @@ export function EditorToolbar({
   fieldName,
   textAreaRef,
   uploadFiles,
+  copyFromParent,
 }: {
   fieldName: string;
   uploadFiles?: (files: Array<File>) => unknown;
   textAreaRef: RefObject<HTMLTextAreaElement>;
+  copyFromParent?: () => void;
 }) {
   const parts: Array<ReactNode> = [];
   if (uploadFiles != null) {
@@ -127,6 +135,15 @@ export function EditorToolbar({
   if (fieldName === InternalFieldName.Summary && Internal.GenerateSummaryButton) {
     parts.push(<Internal.GenerateSummaryButton key="generate-summary" />);
   }
+  if (copyFromParent != null) {
+    parts.push(
+      <Tooltip title="Copy from previous commit" key="copy-parent">
+        <Button icon onClick={copyFromParent}>
+          <Icon icon="clippy" />
+        </Button>
+      </Tooltip>,
+    );
+  }
   if (uploadFiles != null) {
     parts.push(<FilePicker key="picker" uploadFiles={uploadFiles} />);
   }