isPartiallyCurrent error in matching

[Andreas Ottosson]

Hi!

The following code produces a match for /pro when on /products using isPartiallyCurrent, is this correct? We are trying to use this to add active styling to top level Links when on subpages. So /products/product1 should not match /pro but it should match /products. Perhaps isPartiallyCurrent is not what we are looking for?

import React from "react";
import { render } from "react-dom";
import { Router, Link, Match } from "@reach/router";

const NavLink = (props) => (
  <Link
    {...props}
    getProps={({ isPartiallyCurrent }) => {
      // the object returned here is passed to the
      // anchor element's props
      return {
        style: {
          color: isPartiallyCurrent ? "red" : "blue"
        }
      };
    }}
  />
);

const App = (props) => (
  <div>
    <h1>Active Links</h1>
    <nav>
      <NavLink to="/products">Products</NavLink>
      <NavLink to="/pro">Professional</NavLink>
    </nav>
    {props.children}
  </div>
);

const Products = () => (
  <div>
    <h2>Products</h2>
    <NavLink to="/products/product1">Product 1</NavLink>
  </div>
);

const Product1 = () => (
  <div>
    <h2>Product 1</h2>
    <p>My fancy product.</p>
  </div>
);

const Professional = () => (
  <div>
    <h2>Professional</h2>
  </div>
);

render(
  <Router>
    <App path="/">
      <Products path="/products" />
      <Product1 path="/products/product1" />
      <Professional path="/pro" />
    </App>
  </Router>,
  document.getElementById("root")
);

You can run this easily by pasting this code over index.js in this example https://reach.tech/router/example/active-links :)

Best regards,
Andreas

[Andreas Ottosson]

So to give some more constructive feedback this is how I solved it,

const isPartiallyActiveExact = (props) => {
  const currentLocation = props.location.pathname
  const toProp = props.href
  const regex = new RegExp(`${toProp}/`, 'i')
  if (regex.test(currentLocation) || currentLocation === toProp) {
    return { className: 'active' }
  }
}

and used getProps={isPartiallyActiveExact} on the Link's that needed this. This makes sure that /pro does not match /products etc. but /pro/someotherpage will match as partially active which to me is more correct. Perhaps this could be implemented as isPartiallyActiveExact or something like that?