feat(mongodb): support db.getSiblingDB()

packages/app-tests/mongoShellCommand.test.ts

@@ -6,6 +6,7 @@ import {
   evaluateMongoWriteSafety,
   mongoAggregateWriteStage,
   listChainedCalls,
+  MONGO_SHELL_COMMAND_HINT,
   parseMongoFindExplainCommand,
   mongoBulkWriteToQueryResult,
   mongoCollectionStatsToQueryResult,
@@ -360,6 +361,45 @@ test("parseMongoFindCommand does not rewrite constructor text inside strings", (
   assert.deepEqual(JSON.parse(command.filter), { label: "new Date()", note: "ObjectId()" });
 });
 
+test("parseMongoCommand wraps db.getSiblingDB() commands with the target database", () => {
+  // The exact command from #3936.
+  const parsed = parseMongoCommand(`db.getSiblingDB("iam_account").getCollection("user")
+    .find({_id: NumberLong('144115205316939462')})
+    .sort({phone: 1})
+    .limit(21);`);
+  assert.ok(parsed && parsed.command.kind === "inDatabase");
+  assert.equal(parsed.command.database, "iam_account");
+  assert.equal(parsed.command.command.kind, "find");
+  assert.equal((parsed.command.command as { limit: number }).limit, 21);
+  assert.equal((parsed.command.command as { collection: string }).collection, "user");
+
+  assert.equal(parseMongoCommand("db.getSiblingDB('other').orders.updateOne({a: 1}, {$set: {b: 2}})")?.command.kind, "inDatabase");
+  assert.equal(parseMongoCommand('db . getSiblingDB( "x" ) . stats()')?.command.kind, "inDatabase");
+  // A sibling command is one statement in a batch, and a plain one after it is unaffected.
+  assert.deepEqual(
+    splitMongoCommandRanges('db.getSiblingDB("a").c.find({});\ndb.d.find({})').map((range) => range.command.kind),
+    ["inDatabase", "find"],
+  );
+  // A command that parses is not a failure, even when asked directly.
+  assert.equal(describeMongoCommandParseFailure('db.getSiblingDB("other").c.find({})'), MONGO_SHELL_COMMAND_HINT);
+});
+
+test("parseMongoCommand rejects malformed db.getSiblingDB() with a specific reason", () => {
+  for (const [source, expected] of [
+    ['db.getSiblingDB("x")', /requires a database name string followed by a command/],
+    ['db.getSiblingDB("").c.find({})', /requires a database name string/],
+    ["db.getSiblingDB(1).c.find({})", /requires a database name string/],
+    ['db.getSiblingDB("x", "y").c.find({})', /requires a database name string/],
+    ['db.getSiblingDB("x").getSiblingDB("y").c.find({})', /cannot be chained/],
+    // Errors inside the wrapped command are reported as they would be without the prefix.
+    ['db.getSiblingDB("x").c.replaceOne({a: 1}, {$set: {b: 2}})', /must not contain update operators such as \$set/],
+    ['db.getSiblingDB("x").c.bogus()', /Collection method bogus\(\) is not supported/],
+  ] as const) {
+    assert.equal(parseMongoCommand(source), null, source);
+    assert.match(describeMongoCommandParseFailure(source), expected, source);
+  }
+});
+
 test('parseMongoCommand accepts db["name"] bracket collection accessors', () => {
   const find = parseMongoFindCommand('db["orders-2024"].find({a: 1})');
   assert.ok(find);
@@ -1433,7 +1473,7 @@ test("describeMongoCommandParseFailure names unsupported methods and points at a
   assert.match(describeMongoCommandParseFailure('db.getCollection("my-coll").watch()'), /watch\(\) is not supported/);
 
   assert.match(describeMongoCommandParseFailure("db.getCollectionNames()"), /db\.getCollectionNames\(\) is not supported; collections are listed in the sidebar/);
-  assert.match(describeMongoCommandParseFailure('db.getSiblingDB("other").c.find({})'), /use <database>/);
+  assert.match(describeMongoCommandParseFailure("db.currentOp()"), /db\.currentOp\(\) is not supported/);
   assert.match(describeMongoCommandParseFailure("db.adminCommand({ping: 1})"), /use db\.runCommand/);
   assert.match(describeMongoCommandParseFailure("show collections"), /listed in the sidebar/);