SERVER-40446 Add "NonResumableChangeStreamError" error label

Give the "NonRetryableChangeStreamError" error class a more
appropriate name and propagate it to an "errorLabel" in the command
response.

1 files changed, 33 insertions, 0 deletions

diff --git a/jstests/change_streams/error_label.js b/jstests/change_streams/error_label.js
new file mode 100644
index 00000000000..1c9a00db356
--- /dev/null
+++ b/jstests/change_streams/error_label.js
@@ -0,0 +1,33 @@
+/**
+ * Test that an erroneous Change Stream pipeline responds with an error that includes the
+ * "NonResumableChangeStreamError" label.
+ */
+
+(function() {
+    "use strict";
+
+    load("jstests/libs/collection_drop_recreate.js");  // For assertDropAndRecreateCollection.
+
+    // Drop and recreate the collections to be used in this set of tests.
+    const coll = assertDropAndRecreateCollection(db, "change_stream_error_label");
+
+    // Attaching a projection to the Change Stream that filters out the resume token (stored in the
+    // _id field) guarantees a ChangeStreamFatalError as soon as we get the first change.
+    const changeStream = coll.watch([{$project: {_id: 0}}], {batchSize: 1});
+    assert.commandWorked(coll.insert({a: 1}));
+
+    const err = assert.throws(function() {
+        // Call hasNext() until it throws an error or unexpectedly returns true. We need the
+        // assert.soon() to keep trying here, because the above insert command isn't immediately
+        // observable to the change stream in sharded configurations.
+        assert.soon(function() {
+            return changeStream.hasNext();
+        });
+    });
+
+    // The hasNext() sends a getMore command, which should generate a ChangeStreamFatalError reply
+    // that includes the NonResumableChangeStreamError errorLabel.
+    assert.commandFailedWithCode(err, ErrorCodes.ChangeStreamFatalError);
+    assert("errorLabels" in err, err);
+    assert.contains("NonResumableChangeStreamError", err.errorLabels, err);
+}());
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