test(graphql-transformer-core): add direct unit tests for getGlobalSecondaryIndexes accessor

Author: Simone319

packages/amplify-graphql-transformer-core/src/__tests__/utils/schema-utils.test.ts

@@ -0,0 +1,43 @@
+import { Stack } from 'aws-cdk-lib';
+import { AttributeType, Table } from 'aws-cdk-lib/aws-dynamodb';
+import { getGlobalSecondaryIndexes } from '../../utils/schema-utils';
+
+describe('getGlobalSecondaryIndexes', () => {
+  it('reads the indexes off a real DynamoDB L2 Table regardless of the installed aws-cdk-lib field name', () => {
+    const table = new Table(new Stack(), 'TestTable', {
+      partitionKey: { name: 'id', type: AttributeType.STRING },
+    });
+    table.addGlobalSecondaryIndex({
+      indexName: 'byName',
+      partitionKey: { name: 'name', type: AttributeType.STRING },
+    });
+
+    const indexes = getGlobalSecondaryIndexes(table);
+
+    expect(indexes).toBeDefined();
+    expect(indexes.find((gsi: any) => gsi.indexName === 'byName')).toBeDefined();
+  });
+
+  it('returns the private _globalSecondaryIndexes ArrayBox when present', () => {
+    const indexes = [{ indexName: 'byName', keySchema: [{ attributeName: 'name', keyType: 'HASH' }] }];
+
+    expect(getGlobalSecondaryIndexes({ _globalSecondaryIndexes: indexes })).toBe(indexes);
+  });
+
+  it('falls back to the public globalSecondaryIndexes array (Amplify managed table)', () => {
+    const indexes = [{ indexName: 'byOwner', keySchema: [{ attributeName: 'owner', keyType: 'HASH' }] }];
+
+    expect(getGlobalSecondaryIndexes({ globalSecondaryIndexes: indexes })).toBe(indexes);
+  });
+
+  it('prefers _globalSecondaryIndexes when both fields are populated', () => {
+    const renamed = [{ indexName: 'renamed' }];
+    const legacy = [{ indexName: 'legacy' }];
+
+    expect(getGlobalSecondaryIndexes({ _globalSecondaryIndexes: renamed, globalSecondaryIndexes: legacy })).toBe(renamed);
+  });
+
+  it('returns undefined when neither field is present', () => {
+    expect(getGlobalSecondaryIndexes({})).toBeUndefined();
+  });
+});