fix: prevent TypeError in batch with output parameters when sql errors

When a batch with declared output parameters fails before the appended
`select 1 as [___return___], ...` trailer can run (e.g. a compile error
or a runtime error under SET XACT_ABORT ON), `recordsets` is empty and
`recordsets.pop()[0]` throws synchronously inside the tedious request
callback, preventing the user callback from being invoked and leaving
the request promise unsettled.

Guard the access with optional chaining so the SQL error propagates
through the existing callback path and rejects the promise normally.

Fixes #1863

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: dhensby

lib/tedious/request.js

@@ -477,7 +477,7 @@ class Request extends BaseRequest {
 
           // process batch outputs
           if (batchHasOutput) {
-            if (!this.stream) batchLastRow = recordsets.pop()[0]
+            if (!this.stream) batchLastRow = recordsets.pop()?.[0]
 
             for (const name in batchLastRow) {
               const value = batchLastRow[name]

test/common/tests.js

@@ -644,6 +644,22 @@ module.exports = (sql, driver) => {
       }).catch(done)
     },
 
+    'batch with output parameters and sql error' (done) {
+      const req = new TestRequest()
+      req.output('out', sql.Int)
+      req.batch('select * from notexistingtable').then(() => {
+        done(new Error('expected batch to reject with sql error'))
+      }).catch(err => {
+        try {
+          assert.ok(err instanceof sql.RequestError, `expected RequestError, got ${err && err.constructor.name}: ${err && err.message}`)
+          assert.strictEqual(err.code, 'EREQUEST')
+          done()
+        } catch (assertionError) {
+          done(assertionError)
+        }
+      })
+    },
+
     'create procedure batch' (done) {
       let req = new TestRequest()
       req.batch('create procedure #temporary as select 1 as num').then(result => {

test/msnodesqlv8/msnodesqlv8.js

@@ -74,6 +74,7 @@ describe('msnodesqlv8', function () {
     it('query with pipe and back pressure', (done) => TESTS['query with pipe and back pressure'](done))
     it('batch', done => TESTS.batch(done))
     it('batch (stream)', done => TESTS.batch(done, true))
+    it('batch with output parameters and sql error', done => TESTS['batch with output parameters and sql error'](done))
     it('create procedure batch', done => TESTS['create procedure batch'](done))
     it('prepared statement', done => TESTS['prepared statement'](done))
     it('prepared statement that fails to prepare throws', done => TESTS['prepared statement that fails to prepare throws'](done))

test/tedious/tedious.js

@@ -81,6 +81,7 @@ describe('tedious', () => {
     it('query with pipe and back pressure', (done) => TESTS['query with pipe and back pressure'](done))
     it('query with duplicate output column names', done => TESTS['query with duplicate output column names'](done))
     it('batch', done => TESTS.batch(done))
+    it('batch with output parameters and sql error', done => TESTS['batch with output parameters and sql error'](done))
     it('create procedure batch', done => TESTS['create procedure batch'](done))
     it('prepared statement', done => TESTS['prepared statement'](done))
     it('prepared statement that fails to prepare throws', done => TESTS['prepared statement that fails to prepare throws'](done))