[BUG][typescript-fetch] Compile error when using "noImplicitOverride" in tsconfig

Created by: douniii

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Description

When compiling the generated code with a tsconfig where "noImplicitOverride": true (see here) is set, the compiler complains about the not marked overrides: This member must have an 'override' modifier because it overrides a member in the base class 'Error'.

openapi-generator version

6.0.1 (and master) by using "@openapitools/openapi-generator-cli": "2.5.1"

OpenAPI declaration file content or url

N/A

Generation Details

openapi-generator-cli generate -i ./openapi.json -g typescript-fetch -o src/generated-sources/openapi --additional-properties=supportsES6=true,npmVersion=8.6.0,typescriptThreePlus=true

Steps to reproduce

Checkout https://github.com/OpenAPITools/openapi-generator/tree/master/samples/client/petstore/typescript-fetch/builds/es6-target and add to the tsconfig "noImplicitOverride": true,.

{
  "compilerOptions": {
    "noImplicitOverride": true,
    "declaration": true,
    "target": "es6",
    "module": "commonjs",
    "moduleResolution": "node",
    "outDir": "dist",
    "typeRoots": [
      "node_modules/@types"
    ]
  },
  "exclude": [
    "dist",
    "node_modules"
  ]
}

and build it.

Related issues/PRs

Suggest a fix

Place "override" before overridding props/methods here https://github.com/OpenAPITools/openapi-generator/blob/6d44f97d6cc4bcd11752ca6556075232dc4e5fdb/modules/openapi-generator/src/main/resources/typescript-fetch/runtime.mustache#L222 https://github.com/OpenAPITools/openapi-generator/blob/6d44f97d6cc4bcd11752ca6556075232dc4e5fdb/modules/openapi-generator/src/main/resources/typescript-fetch/runtime.mustache#L229 https://github.com/OpenAPITools/openapi-generator/blob/6d44f97d6cc4bcd11752ca6556075232dc4e5fdb/modules/openapi-generator/src/main/resources/typescript-fetch/runtime.mustache#L230 https://github.com/OpenAPITools/openapi-generator/blob/6d44f97d6cc4bcd11752ca6556075232dc4e5fdb/modules/openapi-generator/src/main/resources/typescript-fetch/runtime.mustache#L236