wp_get_script_polyfill( WP_Scripts $scripts, string[] $tests ): string
- Since
- 5.0.0
- Source
wp-includes/script-loader.php:180
Compatibility
- WordPress
- since 5.0.0
- PHP
- 7.4–8.6-dev
- 6.7.7
- 6.8.8
- 6.9.7
- 7.0.4
- 7.1.0
Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.
Parameters
$scriptsWP_Scripts- WP_Scripts object.
$testsstring[]- Features to detect.
Return value
string- Conditional polyfill inline script.
Performance profile
How much work a call to wp_get_script_polyfill() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.
- Cost class
- Light
- Scaling
- Scales with input
- Instructions
- 6–7
- Plugin surface
- 1 hook
- Called by
- 1
Touches nothing outside its own arguments.
The body loops, so the work grows with what you pass in.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 53.
Third-party callbacks on 'script_loader_src' run inside this call, and their cost is not bounded by anything here.
1 place in core call this, so the cost is paid more often than your own code shows.
What it touches
- hookthird-party callbacks
apply_filters()called directly
What one call costs · 1 distinct outcome
One number would be a lie: the work depends on which branch runs. These are every distinct cost wp_get_script_polyfill() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
| always | 6–7 | none |
Across PHP versions
| PHP | Compiled | Executed | Branches | Notes |
|---|---|---|---|---|
| 8.6-dev | 53 | 6–7 | 8 | |
| 8.5 | 53 | 6–7 | 8 | |
| 8.4 | 53 | 6–7 | 8 | 6 fewer instructions than PHP 8.3 |
| 8.3 | 59 | 6–7 | 8 | |
| 8.2 | 59 | 6–7 | 8 | |
| 8.1 | 59 | 6–7 | 8 | 1 fewer instruction than PHP 7.4 |
| 7.4 | 60 | 6–7 | 8 |
An instruction is not a fixed amount of time, so a matching count is not necessarily the same speed; what it rules out is a difference in the work itself.
Hooks and filters fired · 1
One hook fires while wp_get_script_polyfill() runs, in this order:
- apply_filters( script_loader_src )filterline 199 (+19 into the body)
Filters the script loader source.
Uses · 4
- str_starts_with()Polyfill for `str_starts_with()` function added in PHP 8.0.
- add_query_arg()Retrieves a modified URL query string.
- esc_url()Checks and cleans a URL.
- apply_filters()Calls the callback functions that have been added to a filter hook.
Used by · 1
- twenty_twenty_one_scripts()Enqueues scripts and styles.
Source code
function wp_get_script_polyfill( $scripts, $tests ) { $polyfill = ''; foreach ( $tests as $test => $handle ) { if ( ! array_key_exists( $handle, $scripts->registered ) ) { continue; } $src = $scripts->registered[ $handle ]->src; $ver = $scripts->registered[ $handle ]->ver; if ( ! preg_match( '|^(https?:)?//|', $src ) && ! ( $scripts->content_url && str_starts_with( $src, $scripts->content_url ) ) ) { $src = $scripts->base_url . $src; } if ( ! empty( $ver ) ) { $src = add_query_arg( 'ver', $ver, $src ); } /** This filter is documented in wp-includes/class-wp-scripts.php */ $src = esc_url( apply_filters( 'script_loader_src', $src, $handle ) ); if ( ! $src ) { continue; } $polyfill .= ( // Test presence of feature... '( ' . $test . ' ) || ' . /* * ...appending polyfill on any failures. Cautious viewers may balk * at the `document.write`. Its caveat of synchronous mid-stream * blocking write is exactly the behavior we need though. */ 'document.write( \'<script src="' . $src . '"></scr\' + \'ipt>\' );' ); } return $polyfill;}Changelog
Introduced in 5.0.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
About this page
- Parsed data
- Generated from the wordpress-develop 6.7.7 tag, from
src/wp-includes/script-loader.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it. - Corrections
- Something wrong on this page? Report it and it gets fixed in the next regeneration.