get_category_parents needs improvement

[jayabb]

get_category_parents is fine for internal use and generating URLs etc. but it also has a template tag version which could use some enhancements.

Problems 1: It displays the separator at the end of the list as well as in between categories.

Problem 2: There is no way to override the title attribute when generating links.

Problem 3: This is more of a documentation and code readability issue than anything else, the "nicename" parameter is named back-to-front (i.e. FALSE means you get nice names and TRUE means you get slugs).

The following replacement function fixes all three issues (issue 3 fixed in the parameter name, still needs fixing in the docs):

function get_category_parents($id, $link = FALSE, $separator = '/', $useslug = FALSE, $trailingseparator = TRUE, $usedescfortitle = FALSE)
{
	$output = "";

	// Get the category from the id
	$category = &get_category($id);
	if(is_wp_error($category))
	{
		return $category;
	}

	// Use the slug or the category name
	if($useslug)
	{
		$name = $category->slug;
	}
	else
	{
		$name = $category->cat_name;
	}

	// If this is not a top-level parent, first get the parent of this category.
	if($category->parent && ($category->parent != $category->term_id))
	{
		$output = get_category_parents($category->parent, $link, $separator, $useslug, $trailingseparator, $usedescfortitle);

		// If the parent output did NOT contain a trailing separator
		// we need to add the separator between category names/links
		if(!$trailingseparator)
		{
			$output .= $separator;
		}
	}

	// Output a link or plain text
	if($link)
	{
		$title = "";

		// Use the category description or the default text for the link title
		if($usedescfortitle)
		{
			$title = $category->description;
		}

		if($title == "")
		{
			$title = "View all posts in " . $name;
		}

		// Add this category link onto the end of the string which already contains all of its parent links
		$output .= '<a href="' . get_category_link($category->term_id) . '" title="' . $title . '">' . $name . '</a>';
	}
	else
	{
		// Add this category name onto the end of the string which already contains all of its parent names
		$output .= $name;
	}

	// Add the trailing separator
	if($trailingseparator)
	{
		$output .= $separator;
	}

	return $output;
}

This updated function is backwards compatible with the old one, there should not be any behavioural differences. If someone could integrate and test it in the core for the next release it'd be much appreciated. Also change the docs so that nice name is called use slugs instead.

Ta,
-Jay

Milestone 2.5.2 deleted

Use get_ancestors() in get_category_parents

In 7030.get_ancestors.diff the $visited argument is deprecated, since it's not needed anymore.

We should deprecate the entire function, since the parameters are a mess.

Related: #17069