Keep the initial wrapped line upon dragging

src/browser/selection/SelectionModel.test.ts

@@ -116,6 +116,12 @@ describe('SelectionModel', () => {
       model.selectionStartLength = 4;
       assert.deepEqual(model.finalSelectionEnd, [2, 3]);
     });
+    it('should return the end on a different row when start + length overflows onto a following row with selectionEnd inbetween', () => {
+      model.selectionStart = [78, 2];
+      model.selectionEnd = [79, 2];
+      model.selectionStartLength = 4;
+      assert.deepEqual(model.finalSelectionEnd, [2, 3]);
+    });
     it('should return selection end if selection end is after selection start + length', () => {
       model.selectionStart = [2, 2];
       model.selectionStartLength = 2;

src/browser/selection/SelectionModel.ts

@@ -92,7 +92,12 @@ export class SelectionModel {
     if (this.selectionStartLength) {
       // Select the larger of the two when start and end are on the same line
       if (this.selectionEnd[1] === this.selectionStart[1]) {
-        return [Math.max(this.selectionStart[0] + this.selectionStartLength, this.selectionEnd[0]), this.selectionEnd[1]];
+        // Keep the whole wrapped word/line selected if the content wraps multiple lines
+        const startPlusLength = this.selectionStart[0] + this.selectionStartLength;
+        if (startPlusLength > this._bufferService.cols) {
+          return [startPlusLength % this._bufferService.cols, this.selectionStart[1] + Math.floor(startPlusLength / this._bufferService.cols)];
+        }
+        return [Math.max(startPlusLength, this.selectionEnd[0]), this.selectionEnd[1]];
       }
     }
     return this.selectionEnd;