fix: Fix bug that could cause dragged blocks to connect to and delete others

packages/blockly/core/dragging/block_drag_strategy.ts

@@ -902,7 +902,11 @@ export class BlockDragStrategy implements IDragStrategy {
     blockAnimation.disconnectUiStop();
     this.connectionPreviewer?.hidePreview();
 
-    if (!this.block.isDeadOrDying() && this.dragging) {
+    if (
+      !this.block.isDeadOrDying() &&
+      this.dragging &&
+      disposition !== DragDisposition.DELETE
+    ) {
       // These are expensive and don't need to be done if we're deleting, or
       // if we've already stopped dragging because we moved back to the start.
       this.workspace
@@ -921,7 +925,7 @@ export class BlockDragStrategy implements IDragStrategy {
       this.redisableAllDraggedBlocks(this.block);
     }
 
-    if (this.connectionCandidate) {
+    if (this.connectionCandidate && disposition !== DragDisposition.DELETE) {
       // Applying connections also rerenders the relevant blocks.
       this.applyConnections(this.connectionCandidate);
       this.disposeStep();

packages/blockly/tests/browser/test/dragger_test.mjs

@@ -372,4 +372,50 @@ suite('Dragging into a delete area', function () {
       });
     });
   });
+
+  test('does not delete blocks already on the workspace within the connection radius of a dragged block dropped on a delete area', async function () {
+    const {blockHasDeleteStyle, blockIsDeadOrDying, existingBlockDeleted} =
+      await this.browser.execute(() => {
+        const workspace = Blockly.getMainWorkspace();
+
+        const existingBlock = workspace.newBlock('controls_repeat');
+        existingBlock.initSvg();
+        existingBlock.render();
+
+        const draggingBlock = workspace.newBlock('controls_if');
+        draggingBlock.initSvg();
+        draggingBlock.render();
+
+        const deleteRect = workspace.trashcan.getClientRect();
+        const deleteRectCenter = rectCenterClient(deleteRect);
+
+        // Move the existing block near the trash so that the dragged block will
+        // attempt to connect on top of it.
+        existingBlock.moveTo(
+          new Blockly.utils.Coordinate(
+            deleteRectCenter.x - workspace.toolbox.getClientRect().right - 30,
+            deleteRectCenter.y + existingBlock.height / 2,
+          ),
+        );
+
+        const state = getAssertionState(
+          draggingBlock,
+          deleteRectCenter,
+          deleteRect,
+        );
+
+        return {
+          ...state,
+          existingBlockDeleted: existingBlock.isDeadOrDying(),
+        };
+      });
+
+    chai.assert.isFalse(
+      existingBlockDeleted,
+      'Expected existing block to not be deleted',
+    );
+
+    chai.assert.isTrue(blockHasDeleteStyle);
+    chai.assert.isTrue(blockIsDeadOrDying);
+  });
 });