fix(protect): treat undefined plaintext same as null in encryptQuery

Handle undefined plaintext values consistently with null by returning
early (data: null) before sending to FFI. Updates both single and batch
encrypt-query operations to use `=== null || === undefined` checks.

Author: tobyhede

packages/protect/src/ffi/operations/batch-encrypt-query.ts

@@ -15,8 +15,8 @@ import { assertValidNumericValue } from '../helpers/validation'
 import { encryptedToCompositeLiteral, encryptedToEscapedCompositeLiteral } from '../../helpers'
 
 /**
- * Separates null values from non-null terms in the input array.
- * Returns a set of indices where values are null and an array of non-null terms with their original indices.
+ * Separates null/undefined values from non-null terms in the input array.
+ * Returns a set of indices where values are null/undefined and an array of non-null terms with their original indices.
  */
 function filterNullTerms(
   terms: readonly ScalarQueryTerm[],
@@ -28,7 +28,7 @@ function filterNullTerms(
   const nonNullTerms: { term: ScalarQueryTerm; originalIndex: number }[] = []
 
   terms.forEach((term, index) => {
-    if (term.value === null) {
+    if (term.value === null || term.value === undefined) {
       nullIndices.add(index)
     } else {
       nonNullTerms.push({ term, originalIndex: index })

packages/protect/src/ffi/operations/encrypt-query.ts

@@ -35,7 +35,7 @@ export class EncryptQueryOperation extends ProtectOperation<Encrypted> {
       queryType: this.opts.queryType,
     })
 
-    if (this.plaintext === null) {
+    if (this.plaintext === null || this.plaintext === undefined) {
       return { data: null }
     }
 
@@ -93,7 +93,7 @@ export class EncryptQueryOperationWithLockContext extends ProtectOperation<Encry
   }
 
   public async execute(): Promise<Result<Encrypted, ProtectError>> {
-    if (this.plaintext === null) {
+    if (this.plaintext === null || this.plaintext === undefined) {
       return { data: null }
     }