Mutate nested deep object

April 29, 2022

I have this object

const a = {
  elementErrors: {
    errorMessages: [],
    errors: {
      project: "Issues with this Issue Type must be created in the same project as the parent."
    }
  },
  issueKey: "JP-55",
  status: 400
}

and I want to mutate it so that the nested project property includes the issueKey property at the end of the string, something like "Issues with this Issue Type must be created in the same project as the parent (JP-55)."

I know I should show that I tried and I did but I haven’t managed to come with the beginning of a solution.

The final object would look like this:

const a = {
      elementErrors: {
        errorMessages: [],
        errors: {
          project: "Issues with this Issue Type must be created in the same project as the parent (JP-55)."
        }
      },
      issueKey: "JP-55",
      status: 400
    }

Many thanks

>Solution :

You can use the += operator to ‘add’ something to the end of the string.

a.elementErrors.errors.project += ` (${a.issueKey})`;

let a = {
  elementErrors: {
    errorMessages: [],
    errors: {
      project: "Issues with this Issue Type must be created in the same project as the parent."
    }
  },
  issueKey: "JP-55",
  status: 400
}

a.elementErrors.errors.project += ` (${a.issueKey})`;

console.log(a);