# old/mod.ts
export class Foo {
  bar() {}
}

# new/mod.ts
export abstract class Foo {
  abstract bar(): void;
}

# output.json
{
  "modifiedModules": {
    "file:///mod.ts": {
      "modified": [
        {
          "name": "Foo",
          "declarations": {
            "modified": [
              {
                "kind": "class",
                "defChanges": {
                  "type": "class",
                  "isAbstractChange": {
                    "old": false,
                    "new": true
                  },
                  "methodChanges": {
                    "modified": [
                      {
                        "name": "bar",
                        "isAbstractChange": {
                          "old": false,
                          "new": true
                        }
                      }
                    ]
                  }
                }
              }
            ]
          }
        }
      ]
    }
  }
}
