Unpoly Up-current Bug With Encoded Query Params In Nav Links

by Alex Johnson 61 views

Unpoly is a fantastic framework, but like any software, it has its quirks. One such issue involves the up-current class and how it interacts with encoded query parameters in navigation links. This article delves into a specific bug where the up-current class isn't consistently applied when query parameters are URL-encoded. We'll explore the bug's description, how to reproduce it, the expected behavior, and the context in which this issue arises. Let's dive in and understand this Unpoly behavior.

Bug Description: Inconsistent up-current Class Application

The core of the problem lies in the inconsistent application of the up-current class to navigation links. When query parameters within these links are encoded (e.g., a[]=b becomes a%5B%5D=b), the up-current class, which is crucial for indicating the active link, doesn't always behave as expected.

Specifically, the class is correctly added during regular navigation, meaning when you click on a link with encoded query parameters, the corresponding navigation item gets highlighted as active. However, the issue arises when the address is manually typed (or pasted) into the browser's address bar. In this scenario, the up-current class may fail to be applied, even though the resulting page is the same as if you had navigated via a link click. This discrepancy between click-based navigation and direct URL entry can lead to a confusing user experience, where the active link isn't visually indicated.

The up-current class serves as a visual cue for users, helping them understand their current location within the application. When this class is inconsistently applied, it can disrupt the user's sense of orientation and make navigation feel less intuitive. Therefore, understanding and addressing this bug is vital for ensuring a smooth and user-friendly experience with Unpoly.

The inconsistency primarily stems from how Unpoly handles URL encoding and decoding when matching the current URL against the navigation links. While Unpoly correctly processes encoded URLs during link clicks, the manual entry scenario appears to bypass this processing, leading to a mismatch. This highlights the need for a more robust mechanism for handling URL encoding, ensuring consistent behavior across different navigation methods. This issue can be particularly problematic in applications that heavily rely on query parameters for state management or filtering, as the visual indication of the current state might be lost when users directly manipulate the URL.

Reproduction Project and Steps

To better understand and reproduce this bug, a minimal reproduction project has been created. This project serves as a sandbox, allowing you to witness the inconsistent behavior firsthand and experiment with potential solutions. The project is designed to be simple and self-contained, focusing specifically on the up-current class and URL encoding, minimizing external dependencies and complexities. Here’s how you can reproduce the behavior:

  1. Access the Reproduction Project: Start by navigating to the provided Reproduction Project. This link will take you to a StackBlitz environment, pre-configured with the necessary files and setup to demonstrate the bug. StackBlitz is an online code editor that allows you to run and test web applications directly in your browser, making it an ideal platform for reproducing and debugging web-related issues.
  2. Open Project Preview in a Separate Tab: Once the StackBlitz environment is loaded, open the project preview in a new tab. This will allow you to interact with the application in a more isolated environment, free from the StackBlitz editor interface. You can usually find a button or option within StackBlitz to open the preview in a new tab.
  3. **Initial State: