Is accessing __dirname within function in Node.js considered as impure code?

Question

If I have a function:

function testDirectory(filePath) {
    return __dirname === path.dirname(filePath);
}

Can I call this a pure function? By definition of pure function,

1. It doesn't cause any observable side effect.
2. It always evaluates the same result for same input value.
3. Both the criteria mentioned above are satisfied.

However, depending on where this function is defined, the result changes. So, in a way it is dependent on context ( location in this case.)

Answer 1

Yes, this function is pure since __dirname is a constant. It does not matter at all how that constant did get its value (in this case, during the compilation of the module).