Fix #2160

packages-content-model/roosterjs-content-model-editor/lib/modelApi/common/mergeModel.ts

@@ -58,13 +58,19 @@ export interface MergeModelOption {
 
 /**
  * @internal
+ * Merge source model into target mode
+ * @param target Target Content Model that will merge content into
+ * @param source Source Content Model will be merged to target model
+ * @param context Format context. When call this function inside formatWithContentModel, provide this context so that formatWithContentModel will do extra handling to the result
+ * @param options More options, see MergeModelOption
+ * @returns Insert point after merge, or null if there is no insert point
  */
 export function mergeModel(
     target: ContentModelDocument,
     source: ContentModelDocument,
     context?: FormatWithContentModelContext,
     options?: MergeModelOption
-) {
+): InsertPoint | null {
     const insertPosition =
         options?.insertPosition ?? deleteSelection(target, [], context).insertPoint;
 
@@ -119,6 +125,8 @@ export function mergeModel(
     }
 
     normalizeContentModel(target);
+
+    return insertPosition;
 }
 
 function mergeParagraph(
@@ -186,7 +194,7 @@ function mergeTable(
     newTable: ContentModelTable,
     source: ContentModelDocument
 ) {
-    const { tableContext } = markerPosition;
+    const { tableContext, marker } = markerPosition;
 
     if (tableContext && source.blocks.length == 1 && source.blocks[0] == newTable) {
         const { table, colIndex, rowIndex } = tableContext;
@@ -226,10 +234,19 @@ function mergeTable(
                     }
                 }
 
+                const oldCell = table.rows[rowIndex + i].cells[colIndex + j];
                 table.rows[rowIndex + i].cells[colIndex + j] = newCell;
 
                 if (i == 0 && j == 0) {
-                    addSegment(newCell, createSelectionMarker());
+                    const newMarker = createSelectionMarker(marker.format);
+                    const newPara = addSegment(newCell, newMarker);
+
+                    if (markerPosition.path[0] == oldCell) {
+                        // Update insert point to match the change result
+                        markerPosition.path[0] = newCell;
+                        markerPosition.marker = newMarker;
+                        markerPosition.paragraph = newPara;
+                    }
                 }
             }
         }

packages-content-model/roosterjs-content-model-editor/lib/publicApi/utils/paste.ts

@@ -3,6 +3,8 @@ import { ChangeSource } from '../../publicTypes/event/ContentModelContentChanged
 import { formatWithContentModel } from './formatWithContentModel';
 import { GetContentMode, PasteType as OldPasteType, PluginEventType } from 'roosterjs-editor-types';
 import { mergeModel } from '../../modelApi/common/mergeModel';
+import { setPendingFormat } from '../../modelApi/format/pendingFormat';
+import type { InsertPoint } from '../../publicTypes/selection/InsertPoint';
 import type {
     ContentModelDocument,
     ContentModelSegmentFormat,
@@ -35,6 +37,19 @@ const PasteTypeMap: Record<PasteType, OldPasteType> = {
     mergeFormat: OldPasteType.MergeFormat,
     normal: OldPasteType.Normal,
 };
+const EmptySegmentFormat: Required<ContentModelSegmentFormat> = {
+    backgroundColor: '',
+    fontFamily: '',
+    fontSize: '',
+    fontWeight: '',
+    italic: false,
+    letterSpacing: '',
+    lineHeight: '',
+    strikethrough: false,
+    superOrSubScriptSequence: '',
+    textColor: '',
+    underline: false,
+};
 
 /**
  * Paste into editor using a clipboardData object
@@ -55,6 +70,7 @@ export default function paste(
     }
 
     editor.focus();
+    let originalFormat: ContentModelSegmentFormat | undefined;
 
     formatWithContentModel(
         editor,
@@ -81,14 +97,18 @@ export default function paste(
                 createDomToModelContext(undefined /*editorContext*/, domToModelOption)
             );
 
-            mergePasteContent(
+            const insertPoint = mergePasteContent(
                 model,
                 context,
                 pasteModel,
                 pasteType == 'mergeFormat',
                 customizedMerge
             );
 
+            if (insertPoint) {
+                originalFormat = insertPoint.marker.format;
+            }
+
             return true;
         },
 
@@ -97,6 +117,17 @@ export default function paste(
             getChangeData: () => clipboardData,
         }
     );
+
+    const pos = editor.getFocusedPosition();
+
+    if (originalFormat && pos) {
+        setPendingFormat(
+            editor,
+            { ...EmptySegmentFormat, ...originalFormat }, // Use empty format as initial value to clear any other format inherits from pasted content
+            pos.node,
+            pos.offset
+        );
+    }
 }
 
 /**
@@ -110,16 +141,14 @@ export function mergePasteContent(
     applyCurrentFormat: boolean,
     customizedMerge:
         | undefined
-        | ((source: ContentModelDocument, target: ContentModelDocument) => void)
-) {
-    if (customizedMerge) {
-        customizedMerge(model, pasteModel);
-    } else {
-        mergeModel(model, pasteModel, context, {
-            mergeFormat: applyCurrentFormat ? 'keepSourceEmphasisFormat' : 'none',
-            mergeTable: shouldMergeTable(pasteModel),
-        });
-    }
+        | ((source: ContentModelDocument, target: ContentModelDocument) => InsertPoint | null)
+): InsertPoint | null {
+    return customizedMerge
+        ? customizedMerge(model, pasteModel)
+        : mergeModel(model, pasteModel, context, {
+              mergeFormat: applyCurrentFormat ? 'keepSourceEmphasisFormat' : 'none',
+              mergeTable: shouldMergeTable(pasteModel),
+          });
 }
 
 function shouldMergeTable(pasteModel: ContentModelDocument): boolean | undefined {

packages-content-model/roosterjs-content-model-editor/lib/publicTypes/event/ContentModelBeforePasteEvent.ts

@@ -1,3 +1,4 @@
+import type { InsertPoint } from '../selection/InsertPoint';
 import type { ContentModelDocument, DomToModelOption } from 'roosterjs-content-model-types';
 import type {
     BeforePasteEvent,
@@ -16,7 +17,10 @@ export interface ContentModelBeforePasteEventData extends BeforePasteEventData {
     /**
      * customizedMerge Customized merge function to use when merging the paste fragment into the editor
      */
-    customizedMerge?: (target: ContentModelDocument, source: ContentModelDocument) => void;
+    customizedMerge?: (
+        target: ContentModelDocument,
+        source: ContentModelDocument
+    ) => InsertPoint | null;
 }
 
 /**