We have the URL.

let urlC = "http://example.com"

We want to communicate via our unit tests that new URL(urlC).pathname results in /.

Approach

Since there is no path in the URL we may expect the path to be "" , however it is /, which is good for our API users to know.

let urlA = "http://example.com/aa/bb/"
let urlB = "http://example.com/"
let urlC = "http://example.com"
it(`should be true`, () => {
    expect(isURLPathsEqual(urlA, "/aa/bb/").value).toBeTruthy();
    expect(isURLPathsEqual(urlB, "/").value).toBeTruthy();
    expect(isURLPathsEqual(urlC, "/").value).toBeTruthy();
})
it(`should be false`, () => {
    expect(isURLPathsEqual(urlA, "/aa/bb/cc").value).toBeFalsy();
    expect(isURLPathsEqual(urlC, "").value).toBeFalsy();
})

For the isURLPathsEqual implementation see this link.

For the corresponding tests see this link.

And for the NPM repository containing the validators and sanitizers see this link.

Communicating API Semantics Through Unit Tests | Task

Scenario

Approach