fix(amplify-cli-core): extend js-yaml.JSON_SCHEMA to inherit json typ…

…e conversions when parsing .yml cfn templates (#7909)

* fix(amplify-cli-core): extend js-yaml.JSON_SCHEMA to inherit json type conversions

Instead of creating a js-yaml schema that only contains conversions for cloudformation intrinsic
functions, we should extend the built-in JSON-SCHEMA to inherit type conversions for bools, ints,
floats, etc.

fix #7819

* test(amplify-cli-core): add regression tests

packages/amplify-cli-core/src/__tests__/cfnUtilities.test.ts

@@ -73,6 +73,42 @@ describe('readCFNTemplate', () => {
       }
     `);
   });
+
+  it('casts yaml boolean values to corresponding JavaScript boolean', async () => {
+    const yamlContent = `
+      someKey: true
+      someOtherKey: false
+      someStringKey: "true"
+    `;
+
+    ((fs_mock.readFile as unknown) as jest.MockedFunction<TwoArgReadFile>).mockResolvedValueOnce(yamlContent);
+
+    const result = await readCFNTemplate(testPath);
+
+    expect(result.cfnTemplate).toEqual({
+      someKey: true,
+      someOtherKey: false,
+      someStringKey: 'true',
+    });
+  });
+
+  it('casts yaml integer and float values to corresponding JavaScript number', async () => {
+    const yamlContent = `
+      someKey: 1
+      someOtherKey: 1.234
+      someStringKey: "1.234"
+    `;
+
+    ((fs_mock.readFile as unknown) as jest.MockedFunction<TwoArgReadFile>).mockResolvedValueOnce(yamlContent);
+
+    const result = await readCFNTemplate(testPath);
+
+    expect(result.cfnTemplate).toEqual({
+      someKey: 1,
+      someOtherKey: 1.234,
+      someStringKey: '1.234',
+    });
+  });
 });
 
 describe('writeCFNTemplate', () => {

packages/amplify-cli-core/src/cfnUtilities.ts

@@ -66,7 +66,7 @@ export async function writeCFNTemplate(template: object, filePath: string, optio
 
 // Register custom tags for yaml parser
 // Order and definition based on docs: https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/intrinsic-function-reference.html
-const CF_SCHEMA = new yaml.Schema([
+const CF_SCHEMA = yaml.JSON_SCHEMA.extend([
   new yaml.Type('!Base64', {
     kind: 'scalar',
     construct: function (data) {