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demo/demo.ts

@@ -11,7 +11,7 @@ import { schema as baseSchema } from 'prosemirror-schema-basic';
 import { keymap } from 'prosemirror-keymap';
 import { exampleSetup, buildMenuItems } from 'prosemirror-example-setup';
 import { MenuItem, Dropdown } from 'prosemirror-menu';
-import { imeSpan } from 'prosemirror-safari-ime-span';
+import { imeSpan } from '../src/ime';
 import {
   addColumnAfter,
   addColumnBefore,

src/ime/browser.ts

@@ -0,0 +1,12 @@
+// Copied from https://github.com/prosemirror/prosemirror-view/blob/1.33.8/src/browser.ts
+
+const nav = typeof navigator != 'undefined' ? navigator : null
+const agent = (nav && nav.userAgent) || ''
+
+const ie_edge = /Edge\/(\d+)/.exec(agent)
+const ie_upto10 = /MSIE \d/.exec(agent)
+const ie_11up = /Trident\/(?:[7-9]|\d{2,})\..*rv:(\d+)/.exec(agent)
+
+const ie = !!(ie_upto10 || ie_11up || ie_edge)
+
+export const safari = !ie && !!nav && /Apple Computer/.test(nav.vendor)

src/ime/index.ts

@@ -0,0 +1,55 @@
+import {
+  Plugin,
+  PluginKey,
+  type PluginSpec,
+  type EditorState,
+} from 'prosemirror-state';
+import { Decoration, DecorationSet, type EditorView } from 'prosemirror-view';
+
+import { safari } from './browser';
+
+const key = new PluginKey<boolean>('safari-ime-span');
+
+let isComposing = false;
+
+const spec: PluginSpec<any> = {
+  key,
+  props: {
+    decorations: createDecorations,
+    handleDOMEvents: {
+      compositionstart: () => {
+        isComposing = true;
+      },
+      compositionend: () => {
+        isComposing = false;
+      },
+    },
+  },
+};
+
+function createDecorations(state: EditorState): DecorationSet | undefined {
+  const { $from, $to, to } = state.selection;
+  if (isComposing && $from.sameParent($to)) {
+    const deco = Decoration.widget(to, createSpan, {
+      ignoreSelection: true,
+      key: 'safari-ime-span',
+    });
+    return DecorationSet.create(state.doc, [deco]);
+  }
+}
+
+function createSpan(view: EditorView): HTMLSpanElement {
+  const span = view.dom.ownerDocument.createElement('span');
+  span.className = 'ProseMirror-safari-ime-span';
+  return span;
+}
+
+/**
+ * A plugin as a workaround for a bug in Safari that causes the composition
+ * based IME to remove the empty HTML element with CSS `position: relative`.
+ *
+ * See also https://github.com/ProseMirror/prosemirror/issues/934
+ *
+ * @public @group Plugins
+ */
+export const imeSpan = new Plugin(safari ? spec : { key });