This works:

arr[-1] = 42 // arr[arr.length - 1] = 42

(The parent node is an AssignmentExpression.)

And this works:

let foo = arr[-1] // let foo = arr[arr.length - 1]

(The parent node is a VariableDeclarator.)

But this doesn't work:

foo = arr[-1] // foo = arr[-1]

(The parent node is an AssignmentExpression.)

This condition is meant to exclude lvalue MemberExpressions (like the first example), which are handled separately, but also excludes these expressions, which should be included:

• Babel: 7.7.4
• babel-plugin-array-last-index: 0.0.4
• OS: Linux (Arch)