Repo: Build failure on main: prefer-readonly.test.ts unit tests

[JoshuaKGoldberg]

Suggestion

https://github.com/typescript-eslint/typescript-eslint/actions/runs/7450497628/job/20269616606

Summary of all failing tests
 FAIL  tests/rules/prefer-readonly.test.ts (7.204 s, 224 MB heap size)
  ● prefer-readonly › invalid › 
...

There are a few failing tests. Full output here.

Summary of all failing tests
 FAIL  tests/rules/prefer-readonly.test.ts (7.204 s, 224 MB heap size)
  ● prefer-readonly › invalid › 
        class Test {
          private prop: number = 3;
        
          test() {
            const that = {} as this & { _foo: 'bar' };
            that._foo = 1;
          }
        }
      
    assert.strictEqual(received, expected)
    Expected value to strictly be equal to:
      "
            class Test {
              private readonly prop: number = 3·
              test() {
                const that = {} as this & {_foo: 'bar'}
                that._foo = 1
              }
            }
          "
    Received:
      "
            class Test {
              private readonly prop: number = 3;·········
        
          constructor() {
            const that = {} as this & { _foo: 'bar' };
            that.prop = 1;
          }
        }
      
    assert.strictEqual(received, expected)
    Expected value to strictly be equal to:
      "
            class Test {
              private readonly prop: number·
              constructor() {
                const that = {} as this & {_foo: 'bar'}
                that.prop = 1
              }
            }
          "
    Received:
      "
            class Test {
              private readonly prop: number;·········
              constructor() {
                const that = {} as this & { _foo: 'bar' };
                that.prop = 1;
              }
            }
          "
    
    Message:
      Output is incorrect.
    Difference:
    - Expected
    + Received
              class Test {
    -           private readonly prop: number
    -
    +           private readonly prop: number;
    +         
                constructor() {
    -             const that = {} as this & {_foo: 'bar'}
    -             that.prop = 1
    +             const that = {} as this & { _foo: 'bar' };
    +             that.prop = 1;
                }
              }
            

      634 |         }
      635 |         else {
    > 636 |             node_assert_1.default.strictEqual(result.output, item.output, 'Output is incorrect.');
          |                                   ^
      637 |         }
      638 |     }
      639 |     else {

      at RuleTester.strictEqual (../rule-tester/dist/RuleTester.js:636:35)
      at Object.call (../rule-tester/dist/RuleTester.js:237:119)

cc @auvred - the rule was changed in #8169, which at one point did have a passing build but I hadn't noticed it eventually failed on formatting things. No worries on your end, fault on my end for not noticing. I'll fix it up real quick now. We're delayed on releasing anyway from #8220 -> #8221.

[auvred]

Oops, I didn't notice that, sorry... I can send a PR with a fix right now if you tell me

[JoshuaKGoldberg]

For context, I try to make it a habit of sending fixes whenever I broke something - which I consider including approving and/or merging things that caused the error. Responsibility of a maintainer and all that.

[JoshuaKGoldberg]

Fixed by #8223.