refactor: sql-tools (#19717)

server/src/sql-tools/transformers/function.transformer.ts

@@ -0,0 +1,26 @@
+import { SqlTransformer } from 'src/sql-tools/transformers/types';
+import { DatabaseFunction, SchemaDiff } from 'src/sql-tools/types';
+
+export const transformFunctions: SqlTransformer = (item: SchemaDiff) => {
+  switch (item.type) {
+    case 'FunctionCreate': {
+      return asFunctionCreate(item.function);
+    }
+
+    case 'FunctionDrop': {
+      return asFunctionDrop(item.functionName);
+    }
+
+    default: {
+      return false;
+    }
+  }
+};
+
+const asFunctionCreate = (func: DatabaseFunction): string => {
+  return func.expression;
+};
+
+const asFunctionDrop = (functionName: string): string => {
+  return `DROP FUNCTION ${functionName};`;
+};