fix: EXPOSED-161 SQL Server syntax incorrectly allows CASCADE with dropSchema

exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/SchemaUtils.kt

@@ -653,12 +653,12 @@ object SchemaUtils {
      * **Note** that when you are using Mysql or MariaDB, this will fail if you try to drop a schema that
      * contains a table that is referenced by a table in another schema.
      *
-     * @sample org.jetbrains.exposed.sql.tests.shared.SchemaTests
+     * @sample org.jetbrains.exposed.sql.tests.shared.SchemaTests.testDropSchemaWithCascade
      *
      * @param schemas the names of the schema
      * @param cascade flag to drop schema and all of its objects and all objects that depend on those objects.
-     * You don't have to specify this option when you are using Mysql or MariaDB
-     * because whether you specify it or not, all objects in the schema will be dropped.
+     * **Note** This option is not supported by MySQL, MariaDB, or SQL Server, so all objects in the schema will be
+     * dropped regardless of the flag's value.
      * @param inBatch flag to perform schema creation in a single batch
      */
     fun dropSchema(vararg schemas: Schema, cascade: Boolean = false, inBatch: Boolean = false) {

exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/vendors/SQLServerDialect.kt

@@ -312,13 +312,7 @@ open class SQLServerDialect : VendorDialect(dialectName, SQLServerDataTypeProvid
         appendIfNotNull(" AUTHORIZATION ", schema.authorization)
     }
 
-    override fun dropSchema(schema: Schema, cascade: Boolean): String = buildString {
-        append("DROP SCHEMA ", schema.identifier)
-
-        if (cascade) {
-            append(" CASCADE")
-        }
-    }
+    override fun dropSchema(schema: Schema, cascade: Boolean): String = "DROP SCHEMA ${schema.identifier}"
 
     override fun createIndex(index: Index): String {
         if (index.functions != null) {

exposed-tests/src/test/kotlin/org/jetbrains/exposed/sql/tests/shared/SchemaTests.kt

@@ -6,7 +6,6 @@ import org.jetbrains.exposed.sql.tests.DatabaseTestsBase
 import org.jetbrains.exposed.sql.tests.TestDB
 import org.jetbrains.exposed.sql.transactions.TransactionManager
 import org.jetbrains.exposed.sql.transactions.transaction
-import org.jetbrains.exposed.sql.vendors.OracleDialect
 import org.jetbrains.exposed.sql.vendors.SQLServerDialect
 import org.jetbrains.exposed.sql.vendors.currentDialect
 import org.junit.Assume
@@ -56,6 +55,20 @@ class SchemaTests : DatabaseTestsBase() {
         }
     }
 
+    @Test
+    fun testDropSchemaWithCascade() {
+        withDb {
+            if (currentDialect.supportsCreateSchema) {
+                val schema = Schema("TEST_SCHEMA")
+                SchemaUtils.createSchema(schema)
+                assertTrue(schema.exists())
+
+                SchemaUtils.dropSchema(schema, cascade = true)
+                assertFalse(schema.exists())
+            }
+        }
+    }
+
     @Test
     fun `table references table with same name in other database in mysql`() {
         withDb(listOf(TestDB.MYSQL, TestDB.MARIADB)) {