fix(37791): Using object destructuring with ECMAScript's private field as computed property name leads to runtime error

[a-tarasyuk]

Fixes #37791

[rbuckton]

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[typescript-bot]

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[rbuckton]

I don't think this sufficiently resolves the issue. There are two different problems here that need to be addressed:

1. Somewhere in the classFields.ts transform part of the previous AST is being added to the output AST without being visited.
2. Its important to know where the computed property name is. While your fix addresses the object literal case, it is still broken when used with a nested class declaration:

class Foo {
    #value;
    constructor(value) {
        this.#value = value;
    }
    getValue(data) {
        const obj = this;
        class Bar {
            #y;
            [obj.#value]() {}
        }
        return value;
    }
}

I think the problem with (1) is in visitComputedPropertyName:

TypeScript/src/compiler/transformers/classFields.ts

Line 187 in 052d730

expressions.push(name.expression);

This should probably read:

expressions.push(node.expression);

Because name is the original AST node, and node is the visited AST node.

The problem with (2) is that there's only one pendingExpressions array, when this should really be a fresh array when you descend into each new function scope.

Removing visitComputedPropertyName from regular visitors does seem to address (2), but I think we need more tests to be sure.

[a-tarasyuk]

@rbuckton Thanks for the review 👍🏻. I've added additional changes/tests.

[rbuckton]

Looks good!

[a-tarasyuk]

@rbuckton Thanks