snapshot of https://github.com/toeverything/AFFiNE.git (canary, 2026-09-16; blobs > 131072B omitted)

blocksuite/affine/blocks/paragraph/src/utils/merge-with-prev.ts

@@ -0,0 +1,214 @@
+import {
+  AttachmentBlockModel,
+  BookmarkBlockModel,
+  CalloutBlockModel,
+  CodeBlockModel,
+  DatabaseBlockModel,
+  DividerBlockModel,
+  EdgelessTextBlockModel,
+  ImageBlockModel,
+  ListBlockModel,
+  NoteBlockModel,
+  ParagraphBlockModel,
+  type RootBlockModel,
+} from '@blocksuite/affine-model';
+import {
+  asyncSetInlineRange,
+  focusTextModel,
+} from '@blocksuite/affine-rich-text';
+import { EMBED_BLOCK_MODEL_LIST } from '@blocksuite/affine-shared/consts';
+import type { ExtendedModel } from '@blocksuite/affine-shared/types';
+import {
+  focusTitle,
+  getDocTitleInlineEditor,
+  getPrevContentBlock,
+  matchModels,
+} from '@blocksuite/affine-shared/utils';
+import { IS_ANDROID, IS_MOBILE } from '@blocksuite/global/env';
+import { BlockSelection, type EditorHost } from '@blocksuite/std';
+import type { BlockModel, Text } from '@blocksuite/store';
+
+/**
+ * Merge the paragraph with prev block
+ *
+ * Before press backspace
+ * - line1
+ *   - line2
+ *   - |aaa
+ *   - line3
+ *
+ * After press backspace
+ * - line1
+ *   - line2|aaa
+ *   - line3
+ */
+export function mergeWithPrev(editorHost: EditorHost, model: BlockModel) {
+  const doc = model.store;
+  const parent = doc.getParent(model);
+  if (!parent) return false;
+
+  const prevBlock = getPrevContentBlock(editorHost, model);
+  if (!prevBlock) {
+    return handleNoPreviousSibling(editorHost, model);
+  }
+
+  const modelIndex = parent.children.indexOf(model);
+  const prevSibling = doc.getPrev(model);
+  if (matchModels(prevSibling, [CalloutBlockModel])) {
+    editorHost.selection.setGroup('note', [
+      editorHost.selection.create(BlockSelection, {
+        blockId: prevSibling.id,
+      }),
+    ]);
+    return true;
+  }
+
+  if (matchModels(prevBlock, [ParagraphBlockModel, ListBlockModel])) {
+    if (
+      (modelIndex === -1 || modelIndex === parent.children.length - 1) &&
+      parent.role === 'content'
+    )
+      return false;
+
+    const lengthBeforeJoin = prevBlock.props.text?.length ?? 0;
+    prevBlock.props.text.join(model.text as Text);
+    doc.deleteBlock(model, {
+      bringChildrenTo: parent,
+    });
+    asyncSetInlineRange(editorHost.std, prevBlock, {
+      index: lengthBeforeJoin,
+      length: 0,
+    }).catch(console.error);
+
+    // due to some IME like Microsoft Swift IME on Android will reset range after join text,
+    // for example:
+    //
+    // $ZERO_WIDTH_FOR_EMPTY_LINE     <--- p1
+    // |aaa                           <--- p2
+    //
+    // after pressing backspace, during beforeinput event, the native range is (p1, 1) -> (p2, 0)
+    // and after browser and IME handle the event, the native range is (p1, 1) -> (p1, 1)
+    //
+    // a|aa                            <--- p1
+    //
+    // so we need to set range again after join text.
+    if (IS_ANDROID) {
+      setTimeout(() => {
+        asyncSetInlineRange(editorHost.std, prevBlock, {
+          index: lengthBeforeJoin,
+          length: 0,
+        }).catch(console.error);
+      });
+    }
+
+    return true;
+  }
+
+  if (
+    matchModels(prevBlock, [
+      AttachmentBlockModel,
+      BookmarkBlockModel,
+      CodeBlockModel,
+      ImageBlockModel,
+      DividerBlockModel,
+      ...EMBED_BLOCK_MODEL_LIST,
+    ])
+  ) {
+    // due to create a block selection will clear text selection, which lead
+    // the virtual keyboard to be auto closed on mobile. This behavior breaks
+    // the user experience.
+    if (!IS_MOBILE) {
+      const selection = editorHost.selection.create(BlockSelection, {
+        blockId: prevBlock.id,
+      });
+      editorHost.selection.setGroup('note', [selection]);
+    } else {
+      doc.deleteBlock(prevBlock);
+    }
+
+    if (model.text?.length === 0) {
+      doc.deleteBlock(model, {
+        bringChildrenTo: parent,
+      });
+    }
+
+    return true;
+  }
+
+  if (matchModels(parent, [DatabaseBlockModel])) {
+    doc.deleteBlock(model);
+    focusTextModel(editorHost.std, prevBlock.id, prevBlock.text?.yText.length);
+    return true;
+  }
+
+  return false;
+}
+
+function handleNoPreviousSibling(editorHost: EditorHost, model: ExtendedModel) {
+  const doc = model.store;
+  const text = model.text;
+  const parent = doc.getParent(model);
+  if (!parent) return false;
+
+  const focusFirstBlockStart = () => {
+    const firstBlock = parent.firstChild();
+    if (firstBlock) {
+      focusTextModel(editorHost.std, firstBlock.id, 0);
+    }
+  };
+
+  if (matchModels(parent, [NoteBlockModel])) {
+    const hasTitleEditor = getDocTitleInlineEditor(editorHost);
+    const rootModel = model.store.root as RootBlockModel;
+    const title = rootModel.props.title;
+
+    const shouldHandleTitle = parent.isPageBlock() && hasTitleEditor;
+
+    doc.captureSync();
+
+    if (shouldHandleTitle) {
+      let textLength = 0;
+      if (text) {
+        textLength = text.length;
+        title.join(text);
+      }
+      if (model.children.length > 0 || doc.getNext(model)) {
+        doc.deleteBlock(model, {
+          bringChildrenTo: parent,
+        });
+      }
+      // no other blocks, preserve a empty line
+      else {
+        text?.clear();
+      }
+      focusTitle(editorHost, title.length - textLength);
+      return true;
+    }
+
+    // Preserve at least one block to be able to focus on container click
+    if (
+      text?.length === 0 &&
+      (model.children.length > 0 || doc.getNext(model))
+    ) {
+      doc.deleteBlock(model, {
+        bringChildrenTo: parent,
+      });
+      focusFirstBlockStart();
+      return true;
+    }
+  }
+
+  if (
+    matchModels(parent, [EdgelessTextBlockModel]) &&
+    text?.length === 0 &&
+    (model.children.length > 0 || doc.getNext(model))
+  ) {
+    doc.deleteBlock(model, {
+      bringChildrenTo: parent,
+    });
+    focusFirstBlockStart();
+    return true;
+  }
+
+  return false;
+}