Handle missing status field in execute_reply from XEUS-based kernels

news/changelog-1.10.md

@@ -48,6 +48,12 @@ All changes included in 1.10:
 
 - ([#14297](https://github.com/quarto-dev/quarto-cli/pull/14297)): Fix `quarto.utils.is_empty_node()` returning inverted results for text nodes (`Str`, `Code`, `RawInline`).
 
+## Engines
+
+### Jupyter
+
+- ([#14374](https://github.com/quarto-dev/quarto-cli/pull/14374)): Avoid a crash when a third-party Jupyter kernel (observed with Maple 2025, built on XEUS) returns `execute_reply` without the required `status` field. The failing cell is recorded as an error instead of aborting the render. (author: @ChrisJefferson)
+
 ## Other fixes and improvements
 
 - ([#6651](https://github.com/quarto-dev/quarto-cli/issues/6651)): Fix dart-sass compilation failing in enterprise environments where `.bat` files are blocked by group policy.

src/resources/jupyter/notebook.py

@@ -380,9 +380,18 @@ def handle_meta_object(obj):
     if cleanup_cell:
         kernel_supports_daemonization = True
         nb.cells.append(cleanup_cell)
-        client.execute_cell(
-            cell=cleanup_cell, cell_index=len(client.nb.cells) - 1, store_history=False
-        )
+        try:
+            client.execute_cell(
+                cell=cleanup_cell, cell_index=len(client.nb.cells) - 1, store_history=False
+            )
+        except KeyError as e:
+            # Same XEUS-based protocol violation as in cell_execute.
+            # Cleanup failures are non-fatal: trace and continue so the
+            # render still completes (kernel deps just won't be collected).
+            if e.args == ("status",):
+                trace("cleanup cell failed with missing 'status' in execute_reply; kernel deps unavailable")
+            else:
+                raise
         nb.cells.pop()
 
         # record kernel deps after execution (picks up imports that occurred
@@ -563,12 +572,26 @@ def cell_execute(client, cell, index, execution_count, eval_default, store_histo
         # execute (w/o yaml options so that cell magics work)
         source = cell.source
         cell.source = nb_strip_yaml_options(client, cell.source)
-        cell = client.execute_cell(
-            cell=cell,
-            cell_index=index,
-            execution_count=execution_count,
-            store_history=store_history,
-        )
+        try:
+            cell = client.execute_cell(
+                cell=cell,
+                cell_index=index,
+                execution_count=execution_count,
+                store_history=store_history,
+            )
+        except KeyError as e:
+            # Some kernels (e.g. XEUS-based Maple) omit 'status' from
+            # execute_reply on error, violating the Jupyter protocol.
+            # Record the error in the cell outputs rather than crashing.
+            if e.args == ("status",):
+                cell.outputs.append(nbformat.v4.new_output(
+                    output_type="error",
+                    ename="KernelProtocolError",
+                    evalue="Kernel returned execute_reply without status field",
+                    traceback=[],
+                ))
+            else:
+                raise
         cell.source = source
 
         # if lines_to_next_cell is 0 then fix it to be 1