Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
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Description

v6.6.0 generates what we and tsc expected, v7.0.0 doesn't.

openapi-generator version

v7.0.0

OpenAPI declaration file content or url

swagger spec file t.json

{
  "swagger": "2.0",
  "info": {
    "title": "foo APIs",
    "version": "0.0.1"
  },
  "host": "foo.com",
  "paths": {
    "/hello": {}
  },
  "definitions": {
    "protobufAny": {
      "type": "object",
      "properties": {
        "@type": {
          "type": "string"
        }
      },
      "additionalProperties": {}
    }
  }
}

openapi tool configuration file foo.openapitools.json

{
  "npmName": "foo",
  "npmVersion": "0.0.1",
  "snapshot": false,
  "supportsES6": true,
  "modelPropertyNaming": "original"
}

Generation Details

Steps to reproduce

generate code from spec

openapi-generator-cli version-manager set 7.0.0
openapi-generator-cli generate -i t.json --generator-name typescript-axios -o src/gen/foo -c foo.openapitools.json

tsc build failed with v7.0.0

npm run --prefix src/gen/foo build                                                                                

> foo@0.0.1 build
> tsc && tsc -p tsconfig.esm.json

api.ts:39:5 - error TS2411: Property ''@type'' of type 'string' is not assignable to 'string' index type 'object'.

39     '@type'?: string;
       ~~~~~~~


Found 1 error in api.ts:39

Related issues/PRs

Suggest a fix

If we switch back to 6.6.0 everything works as expected:

openapi-generator-cli version-manager set 6.6.0

openapi-generator-cli generate -i t.json --generator-name typescript-axios -o src/gen/foo -c foo.openapitools.json
npm run --prefix src/gen/foo build

we diff v6.6.0 and v7.0.0

 diff -Nuar  src/gen/foo/api.ts /tmp/app/src/gen/foo/api.ts
--- src/gen/foo/api.ts	2023-09-04 13:39:42
+++ /tmp/app/src/gen/foo/api.ts	2023-09-04 13:39:57
@@ -29,7 +29,7 @@
  * @interface ProtobufAny
  */
 export interface ProtobufAny {
-    [key: string]: object | any;
+    [key: string]: object;
 
     /**
      *