PluginProbe
xSpeed Cache: AI-Powered Performance Hub with MCP, Caching & CDN / 1.3.1
xSpeed Cache: AI-Powered Performance Hub with MCP, Caching & CDN v1.3.1
1.3.2 1.3.1 1.3.0 1.2.4 trunk 1.0.0 1.0.1 1.0.2 1.0.3 1.0.4 1.0.5 1.0.6 1.0.7 1.0.8 1.0.9 1.1.0 1.1.1 1.1.2 1.1.3 1.1.4 1.1.5 1.1.6 1.1.7 1.1.8 1.2.0 All 28 releases
xspeed / includes / class-minifier.php

class-minifier.php in xSpeed Cache: AI-Powered Performance Hub with MCP, Caching & CDN 1.3.1, at includes/class-minifier.php

697 lines 28.1 KB
No matching file
Up and down to move Enter to open Esc to close
Raw Download Zip
1 <?php
2 /**
3 * Asset minifier — HTML, CSS, JS.
4 *
5 * Uses matthiasmullie/minify for CSS/JS. Local enqueued assets are minified
6 * once, cached on disk, and the loader URL is rewritten to point at the
7 * cached file.
8 *
9 * @package XSpeed
10 */
11
12 namespace XSpeed;
13
14 defined( 'ABSPATH' ) || exit;
15
16 class Minifier {
17
18 const MIN_SUBDIR = 'min';
19
20 /**
21 * Absolute path to the minified-cache directory. Always derived from
22 * XSPEED_CACHE_DIR (the plugin's own cache root) — never assembled from
23 * arbitrary URL fragments.
24 */
25 public static function min_dir() {
26 return trailingslashit( XSPEED_CACHE_DIR ) . self::MIN_SUBDIR;
27 }
28
29 /**
30 * Public URL of the minified-cache directory. Built from content_url() +
31 * the known relative path, not by string-replacing WP_CONTENT_DIR out of
32 * a filesystem path (which would assume the filesystem layout matches
33 * the URL layout — it does not on Bedrock-style installs, multisite with
34 * mapped domains, or any setup with a relocated wp-content).
35 */
36 private static function min_url() {
37 // XSPEED_CACHE_DIR lives under wp-content (defined in xspeed.php as
38 // WP_CONTENT_DIR . '/cache/xspeed'), so the URL is content_url() +
39 // the known suffix. We do not derive URLs from arbitrary filesystem
40 // paths anywhere in this plugin.
41 $url = trailingslashit( content_url( 'cache/xspeed' ) ) . self::MIN_SUBDIR;
42 // Force the site's scheme: content_url() derives its scheme from
43 // is_ssl(), which is false behind a TLS-terminating reverse proxy, so
44 // it can emit an http:// URL on an https page — the browser then blocks
45 // the minified stylesheet as mixed content and the page renders
46 // unstyled. Match home_url()'s registered scheme instead. (FBS-83633)
47 $scheme = wp_parse_url( home_url(), PHP_URL_SCHEME ) ?: 'https';
48 return set_url_scheme( $url, $scheme );
49 }
50
51 public function __construct() {
52 // Only run on the frontend — never minify wp-admin, AJAX, REST or cron
53 // asset URLs. Page caching already handles the logged-in case for
54 // the HTML response; minify scope is the public frontend.
55 if ( is_admin() || ( defined( 'DOING_AJAX' ) && DOING_AJAX ) || ( defined( 'DOING_CRON' ) && DOING_CRON ) || ( defined( 'REST_REQUEST' ) && REST_REQUEST ) ) {
56 return;
57 }
58
59 // A page-builder editing screen is a front-end URL, so none of the
60 // guards above catch it. Optimizing it breaks the editor outright --
61 // Combine JS reorders the builder's own dependency graph and the
62 // toolbar never renders. There is no speed to win on a logged-in,
63 // uncacheable editing request anyway. (#281)
64 if ( Builder_Editor::is_active() ) {
65 return;
66 }
67
68 // Settings now live in the per-module option (xspeed_module_minify),
69 // owned by XSpeed\Modules\Minify\MinifyModule. We read through
70 // Settings_Manager so schema-validated values are returned even
71 // if the option was hand-edited.
72 $opts = Settings_Manager::get( 'minify' );
73
74 if ( ! empty( $opts['minify_css'] ) ) {
75 add_filter( 'style_loader_src', array( __CLASS__, 'rewrite_style' ), 10, 2 );
76 }
77 if ( ! empty( $opts['minify_js'] ) ) {
78 add_filter( 'script_loader_src', array( __CLASS__, 'rewrite_script' ), 10, 2 );
79 }
80
81 // Phase 4.1a — filter-only "smarter minifier" features. Each is
82 // gated on its own toggle so users can enable any subset.
83 if ( ! empty( $opts['remove_query_strings'] ) ) {
84 add_filter( 'style_loader_src', array( Minify_Filters::class, 'strip_version_query' ), 20 );
85 add_filter( 'script_loader_src', array( Minify_Filters::class, 'strip_version_query' ), 20 );
86 }
87 if ( ! empty( $opts['defer_js'] ) ) {
88 add_filter( 'script_loader_tag', array( Minify_Filters::class, 'defer_script_tag' ), 20, 3 );
89 }
90 if ( ! empty( $opts['delay_js'] ) ) {
91 // Delay applies a transform that's mutually exclusive with
92 // plain defer — when both are on, delay wins (the bootstrap
93 // will re-attach as a regular <script> on interaction).
94 add_filter( 'script_loader_tag', array( Minify_Filters::class, 'delay_script_tag' ), 30, 3 );
95 add_action( 'wp_footer', array( Minify_Filters::class, 'print_delay_bootstrap' ), 1000 );
96 // script_loader_tag only fires for wp_enqueue_script()'d assets.
97 // Analytics / pixel / chat-widget tags printed straight into
98 // wp_head bypass it, and those are usually the heaviest scripts
99 // on the page — so sweep the finished buffer too. Runs before
100 // minify_html (same filter, default priority) and is baked into
101 // the cache file, so it replays on static hits where PHP never
102 // boots.
103 add_filter( 'xspeed_cache_final_html', array( Minify_Filters::class, 'delay_raw_script_tags' ), 20 );
104 // The vendors' own install snippets are INLINE (no src at all),
105 // so the src sweep above never sees them; this one parks an
106 // inline body that names a known third-party host.
107 add_filter( 'xspeed_cache_final_html', array( Minify_Filters::class, 'delay_inline_snippets' ), 21 );
108 }
109 if ( ! empty( $opts['async_css'] ) ) {
110 add_filter( 'style_loader_tag', array( Minify_Filters::class, 'async_style_tag' ), 20, 2 );
111 // style_loader_tag only fires for wp_enqueue_style()'d sheets.
112 // Themes print Google/Bunny/Typekit font CSS as literal <link>
113 // markup in the head, so those sheets never reach the filter and
114 // stay render-blocking — sweep the finished buffer for the known
115 // font-CSS hosts. Baked into the cache file, so it replays on
116 // static hits where PHP never boots.
117 add_filter( 'xspeed_cache_final_html', array( Minify_Filters::class, 'async_raw_font_css_links' ), 22 );
118 }
119
120 /*
121 * CSS combining runs on the FINISHED HTML, not the enqueue queue.
122 *
123 * The queue-walking version could not be made correct: whatever it
124 * wrote at priority 999, WordPress edited afterwards. Core's
125 * wp_maybe_inline_styles() inlines any queued handle carrying a `path`
126 * and sets src=false on it, which silently threw away the combined URL
127 * and took the sheets we had blanked with it — six stylesheets became
128 * one and the site rendered unstyled. See Css_Combine_Buffer's header
129 * for the full trace. (#195)
130 *
131 * Two entry points, because the page cache's filter is not always
132 * available: `xspeed_cache_final_html` fires only on a cacheable MISS,
133 * so on a site with the cache off — or on an excluded URL like /cart —
134 * combining would silently stop working. Css_Combine_Buffer::boot()
135 * opens its own buffer in exactly those cases and no-ops otherwise, so
136 * the page is transformed once either way.
137 */
138 if ( ! empty( $opts['combine_css'] ) ) {
139 add_filter( 'xspeed_cache_final_html', array( Css_Combine_Buffer::class, 'process' ), 5 );
140 Css_Combine_Buffer::boot();
141 }
142 if ( ! empty( $opts['combine_js'] ) ) {
143 // JS stays on the enqueue path for now: dependency order,
144 // async/defer and wp_add_inline_script make it a different
145 // problem, and the reported break is CSS-only. Moving it is worth
146 // its own change rather than doubling the blast radius here.
147 add_action( 'wp_enqueue_scripts', array( Asset_Combiner::class, 'combine_scripts' ), 999 );
148 }
149 }
150
151 /**
152 * HTML elements that participate in an inline formatting context, where
153 * whitespace between two of them renders as a visible space.
154 *
155 * Deliberately excludes <br> (nothing to separate) and replaced/embedded
156 * inline elements that sit alone. Anything not listed is treated as block
157 * level, where inter-tag whitespace collapses to nothing and is safe to
158 * strip. (FBS-84090)
159 */
160 private const INLINE_TAGS = array(
161 'a', 'abbr', 'b', 'bdi', 'bdo', 'cite', 'code', 'data', 'del', 'dfn',
162 'em', 'i', 'ins', 'kbd', 'label', 'mark', 'q', 'rp', 'rt', 'ruby',
163 's', 'samp', 'small', 'span', 'strong', 'sub', 'sup', 'time', 'u',
164 'var', 'wbr', 'img', 'button', 'select', 'output',
165 );
166
167 /** True when $tag renders inline, so whitespace beside it is visible. */
168 private static function is_inline( string $tag ): bool {
169 return in_array( strtolower( $tag ), self::INLINE_TAGS, true );
170 }
171
172 /**
173 * Why minification is being skipped, when it is. '' when it will run.
174 *
175 * minify_html can read "on" in every settings surface while producing
176 * byte-identical HTML, because the guard below silently returns the
177 * input. Field report: a live site showed `minify_html: on` with 3,856
178 * indented lines in the delivered HTML and nothing anywhere explaining
179 * the contradiction — the setting looked broken rather than suppressed.
180 * Callers that report status MUST consult this so the refusal is
181 * visible. (Same class as Cache::static_rewrite_block_reason().)
182 *
183 * @return string 'wp_debug', 'filter', or ''.
184 */
185 public static function skip_reason(): string {
186 $debug_skip = defined( 'WP_DEBUG' ) && WP_DEBUG;
187 if ( ! apply_filters( 'xspeed_skip_minify', $debug_skip ) ) {
188 return '';
189 }
190 // Distinguish the built-in WP_DEBUG rule from a third party
191 // filtering the escape hatch — the fixes are different.
192 return $debug_skip ? 'wp_debug' : 'filter';
193 }
194
195 public static function minify_html( $html ) {
196 if ( '' !== self::skip_reason() ) {
197 return $html;
198 }
199
200 $placeholders = array();
201 $pattern = '#<(pre|textarea|script|style)\b[^>]*>.*?</\1>#is';
202 $html = preg_replace_callback(
203 $pattern,
204 function ( $m ) use ( &$placeholders ) {
205 $key = '__XSPEED_PH_' . count( $placeholders ) . '__';
206 // The placeholder pass exists to protect content whose
207 // whitespace is significant (<pre>, <textarea>) and to keep
208 // the tag-boundary regex off script bodies. <style> and
209 // <script> were grouped in with them, so protection became a
210 // permanent exemption: on builder sites where most CSS is
211 // inline, a page with minify ON shipped fully indented. Minify
212 // the BODY here, before it's stashed, so the outer passes
213 // still never see it. (#2)
214 $placeholders[ $key ] = self::minify_inline_block( $m[0], strtolower( $m[1] ) );
215 return $key;
216 },
217 $html
218 );
219
220 $html = preg_replace( '/<!--(?!\[if).*?-->/s', '', $html );
221 $html = preg_replace( '/\s+/', ' ', $html );
222
223 /*
224 * Collapse whitespace BETWEEN TAGS — but never where it is visible.
225 *
226 * Whitespace separating two INLINE elements is a real, rendered space:
227 * WooCommerce emits `</del> <ins>` for a sale price, and that single
228 * character is the gap between "$32.50" and "$29.50". Stripping it
229 * printed "$32.50$29.50" run together, and only with cache on — the
230 * un-minified page was fine. (FBS-84090)
231 *
232 * So the strip only applies when at least one side is a BLOCK-level
233 * (or non-rendered) tag, where the whitespace collapses away anyway.
234 * Inline-to-inline boundaries keep their single space.
235 */
236 $html = preg_replace_callback(
237 // left tag name (may be a closing tag) … whitespace … right tag name
238 '#</?([a-zA-Z][a-zA-Z0-9-]*)\b[^>]*>\s+<(/?)([a-zA-Z][a-zA-Z0-9-]*)#',
239 static function ( $m ) {
240 // Keep the space only when BOTH sides are inline elements —
241 // that is the one case where it is actually rendered.
242 $keep = self::is_inline( $m[1] ) && self::is_inline( $m[3] );
243 $open = substr( $m[0], 0, strrpos( $m[0], '<' ) ); // through the left tag's '>'
244 return rtrim( $open ) . ( $keep ? ' ' : '' ) . '<' . $m[2] . $m[3];
245 },
246 $html
247 );
248 $html = trim( $html );
249
250 foreach ( $placeholders as $key => $original ) {
251 $html = str_replace( $key, $original, $html );
252 }
253
254 return $html;
255 }
256
257 public static function rewrite_style( $src, $handle ) {
258 unset( $handle );
259 return self::rewrite_asset( $src, 'css' );
260 }
261
262 public static function rewrite_script( $src, $handle ) {
263 $rewritten = self::rewrite_asset( $src, 'js' );
264
265 // Remember the pre-minify URL for this handle. script_loader_tag
266 // runs later and only ever sees the rewritten src (a hashed
267 // /cache/xspeed/min/<key>.js path), so a user's URL-substring
268 // delay/exclusion target would never match once minification is
269 // on. Minify_Filters::original_src() gives those checks the URL
270 // the user actually wrote their target against. (FBS field report)
271 if ( is_string( $handle ) && '' !== $handle && is_string( $src ) && $src !== $rewritten ) {
272 Minify_Filters::remember_original_src( $handle, $src );
273 }
274
275 return $rewritten;
276 }
277
278 /**
279 * Replace a local CSS/JS URL with a cached, minified equivalent.
280 *
281 * @param string $src Original asset URL.
282 * @param string $type 'css' or 'js'.
283 * @return string Possibly rewritten URL.
284 */
285 private static function rewrite_asset( $src, $type ) {
286 if ( ! is_string( $src ) || '' === $src ) {
287 return $src;
288 }
289
290 // Skip already-minified files.
291 if ( false !== strpos( $src, '.min.' ) ) {
292 return $src;
293 }
294
295 // Skip anything we already produced. The Asset_Combiner minifies the
296 // combined body itself before writing combined-<hash>.css under
297 // min/combined/ (issue #331 — that used to be asserted here but was
298 // not actually true, so the artifact shipped unminified), and enqueues it
299 // as `xspeed-combined-css`; the per-file minifier used to re-minify
300 // that combined output into a SECOND file (min/<hash2>.css) with its
301 // own mtime-derived hash. The served HTML then pinned that second
302 // hash, so a purge/regeneration (which changes the combined file's
303 // mtime -> a new hash2) left the cached page pointing at a file that
304 // no longer existed -> 404 -> unstyled/broken frontend. Leaving our
305 // own cache output untouched keeps a single, stable URL end-to-end.
306 if ( false !== strpos( $src, '/cache/xspeed/' ) ) {
307 return $src;
308 }
309
310 // Resolve to a local path; bail if external or unresolvable.
311 $path = self::url_to_path( $src );
312 if ( ! $path || ! is_readable( $path ) ) {
313 return $src;
314 }
315
316 // Build a cache filename keyed on path + mtime so edits invalidate.
317 $mtime = filemtime( $path );
318 $key = md5( $path . '|' . $mtime );
319 $cache = self::cache_path( $key, $type );
320
321 if ( ! file_exists( $cache ) ) {
322 $ok = self::minify_file( $path, $cache, $type );
323 if ( ! $ok ) {
324 return $src;
325 }
326 }
327
328 // Return a URL to the cached file. Built from known constants — never
329 // from str_replace on a filesystem path (which would assume the FS
330 // layout mirrors the URL layout).
331 return self::min_url() . '/' . $key . '.' . $type;
332 }
333
334 private static function minify_file( $source_path, $target_path, $type ) {
335 if ( ! class_exists( '\\MatthiasMullie\\Minify\\CSS' ) ) {
336 return false;
337 }
338
339 // Path-traversal guard: refuse to write anywhere outside our cache
340 // dir, even if a malicious filter ever produced a poisoned key.
341 $cache_root = self::min_dir();
342 self::ensure_dir( $cache_root );
343 $real_root = realpath( $cache_root );
344 $real_dir = realpath( dirname( $target_path ) );
345 if ( ! $real_root || ! $real_dir || 0 !== strpos( $real_dir, $real_root ) ) {
346 return false;
347 }
348
349 try {
350 if ( 'css' === $type ) {
351 // Passing the TARGET path makes matthiasmullie/minify rebase every
352 // relative url(...) / @import against the minified file's location.
353 // Without it, a stylesheet moved from e.g.
354 // .../font-awesome/css/all.css to cache/xspeed/min/<key>.css keeps
355 // its original url(../webfonts/…) — which then resolves against the
356 // cache dir and 404s (missing FontAwesome/eicons/WooCommerce fonts).
357 $minifier = new \MatthiasMullie\Minify\CSS( $source_path );
358 $minified = $minifier->minify( $target_path );
359 return '' !== $minified && file_exists( $target_path );
360 }
361
362 $minifier = new \MatthiasMullie\Minify\JS( $source_path );
363 $minified = $minifier->minify();
364
365 // Sanity check: paren/brace/bracket/backtick balance must be preserved.
366 // matthiasmullie/minify can silently truncate mid-template-literal on
367 // complex modern JS — bail rather than ship a broken file.
368 // phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents -- WP_Filesystem requires admin context; minification runs on frontend page renders. Source already validated as readable on line 121.
369 $source = file_get_contents( $source_path );
370 if ( false === $source || ! self::balanced( $source, $minified ) ) {
371 return false;
372 }
373
374 // phpcs:ignore WordPress.WP.AlternativeFunctions.file_put_contents_file_put_contents -- WP_Filesystem requires admin context; minification runs on frontend page renders.
375 $bytes = file_put_contents( $target_path, $minified );
376 return false !== $bytes && file_exists( $target_path );
377 } catch ( \Throwable $e ) {
378 return false;
379 }
380 }
381
382 /**
383 * Cheap structural sanity check between source + minified bodies.
384 *
385 * Counts paired-delimiter tokens (parens, braces, brackets, backticks)
386 * in each and bails when the counts disagree — matthiasmullie/minify
387 * has been observed to silently truncate inside template literals on
388 * complex modern JS (see commit history), shipping a body that LOOKS
389 * minified but is structurally broken and crashes the page at parse.
390 *
391 * Backticks are paired (open + close = same token), so the count
392 * itself must match exactly. Strings inside the source can contain
393 * literal `{` / `}` / `[` / `]` that throw off the count by the same
394 * amount in both bodies (since they survive minification as-is), so
395 * the equality check is robust to that noise.
396 */
397 /**
398 * Minify the body of one captured inline block, or return it untouched.
399 *
400 * Only `<style>` and JavaScript `<script>` bodies are eligible:
401 *
402 * - `<pre>` / `<textarea>` — whitespace is rendered, never touch it.
403 * - `<script>` with a non-JS `type` — `application/ld+json`,
404 * `text/template`, `text/x-handlebars` and anything unrecognised are
405 * data or markup, not code. Minifying JSON-LD would corrupt structured
406 * data; minifying a template would eat the markup it holds. An unknown
407 * type is treated as non-JS on purpose: guessing wrong breaks the page,
408 * while skipping only forgoes a few bytes.
409 * - `<script src="...">` — the body is empty; the file path already goes
410 * through minify_file().
411 *
412 * Every result is checked with balanced(), the same structural guard the
413 * file path uses, so a body the library truncates is shipped as-is rather
414 * than broken. (#2)
415 *
416 * @param string $block Full matched tag, opening tag through closing tag.
417 * @param string $tag Lowercased tag name.
418 * @return string Minified block, or $block unchanged.
419 */
420 private static function minify_inline_block( string $block, string $tag ): string {
421 if ( 'style' !== $tag && 'script' !== $tag ) {
422 return $block; // pre / textarea — significant whitespace.
423 }
424 if ( ! class_exists( '\\MatthiasMullie\\Minify\\CSS' ) ) {
425 return $block;
426 }
427
428 // Split into opening tag / body / closing tag. Anything that doesn't
429 // match this shape isn't something we should be rewriting.
430 if ( ! preg_match( '#^(<' . $tag . '\b[^>]*>)(.*)(</' . $tag . '\s*>)$#is', $block, $parts ) ) {
431 return $block;
432 }
433 list( , $open, $body, $close ) = $parts;
434
435 if ( '' === trim( $body ) ) {
436 return $block;
437 }
438
439 // Refuse a body that is already structurally broken. balanced() only
440 // compares source against minified, so it passes when BOTH are equally
441 // unbalanced — `function x( {` minifies to `function x({`, same counts,
442 // guard satisfied, broken code reformatted. Rewriting a body we can't
443 // parse risks turning a page that happens to work into one that does
444 // not, for no gain. (#2 AC: a syntactically broken block is left
445 // untouched.)
446 if ( ! self::self_consistent( $body ) ) {
447 return $block;
448 }
449
450 if ( 'script' === $tag ) {
451 // An external script has no body worth minifying.
452 if ( preg_match( '#\bsrc\s*=#i', $open ) ) {
453 return $block;
454 }
455 // No type, or an explicitly JavaScript type, is code. Everything
456 // else is data/markup — see the docblock.
457 $js_types = array(
458 'text/javascript',
459 'application/javascript',
460 'application/ecmascript',
461 'text/ecmascript',
462 'module',
463 );
464 if ( preg_match( '#\btype\s*=\s*["\']?([^"\'\s>]+)#i', $open, $type_match ) ) {
465 if ( ! in_array( strtolower( trim( $type_match[1] ) ), $js_types, true ) ) {
466 return $block;
467 }
468 }
469 }
470
471 try {
472 $minifier = 'style' === $tag
473 ? new \MatthiasMullie\Minify\CSS()
474 : new \MatthiasMullie\Minify\JS();
475 $minifier->add( $body );
476 $minified = $minifier->minify();
477 } catch ( \Throwable $e ) {
478 return $block;
479 }
480
481 // A minifier that returns nothing for a non-empty body has failed, not
482 // succeeded — shipping '' would silently delete the rule set.
483 if ( ! is_string( $minified ) || '' === trim( $minified ) ) {
484 return $block;
485 }
486 if ( ! self::balanced( $body, $minified ) ) {
487 return $block;
488 }
489
490 return $open . $minified . $close;
491 }
492
493 /**
494 * Does a body's own paired delimiters balance?
495 *
496 * balanced() is a RELATIVE check — source against minified — so it cannot
497 * see input that was already broken: an unbalanced body minifies to an
498 * equally unbalanced one and the counts still agree. This is the absolute
499 * check, applied to the source alone before we touch it.
500 *
501 * Deliberately naive: it counts tokens without parsing, so a brace inside
502 * a string or comment skews it. That only ever makes it MORE conservative —
503 * a false negative skips minification, which costs bytes, while a false
504 * positive would ship broken code. (#2)
505 *
506 * @param string $body Inline block body.
507 */
508 private static function self_consistent( string $body ): bool {
509 $pairs = array(
510 '{' => '}',
511 '(' => ')',
512 '[' => ']',
513 );
514 foreach ( $pairs as $open => $close ) {
515 if ( substr_count( $body, $open ) !== substr_count( $body, $close ) ) {
516 return false;
517 }
518 }
519 // Backticks and quotes pair with themselves, so an odd count means an
520 // unterminated literal.
521 foreach ( array( '`' ) as $token ) {
522 if ( 0 !== substr_count( $body, $token ) % 2 ) {
523 return false;
524 }
525 }
526 return true;
527 }
528
529 private static function balanced( string $source, string $minified ): bool {
530 unset( $source );
531
532 // Judge the OUTPUT, not the difference between input and output.
533 //
534 // This used to compare token counts across the pair, on the stated
535 // assumption that "literal braces inside strings survive minification
536 // unchanged, so they cancel out". Comments do not: stripping them is
537 // the minifier's whole job, and every brace, bracket and backtick
538 // inside one disappears with it. So any file whose comments contain a
539 // delimiter — a commented-out block, a URL in a docblock, an SVG in a
540 // note — failed the check and silently shipped unminified.
541 //
542 // It is not a rare shape. EmbedPress's front.js counts 372 braces
543 // against 368, 61 brackets against 58 and 110 backticks against 102
544 // purely from comment removal, so 67 KB shipped raw where 46 KB was
545 // correct — and `node --check` confirms that rejected output parses
546 // fine. A guard that refuses valid work is not conservative, it is
547 // broken: it costs bytes on every request and reports nothing.
548 //
549 // What the guard is FOR still stands (#2): matthiasmullie/minify can
550 // truncate inside a template literal on complex modern JS and return a
551 // body that looks minified but is structurally broken. That failure is
552 // visible in the output alone — an unterminated literal leaves an odd
553 // backtick count and unmatched braces — which is exactly what
554 // self_consistent() measures, without the false positives.
555 return self::self_consistent( $minified );
556 }
557
558 /**
559 * Resolve a local asset URL to a filesystem path using a strict allowlist
560 * of "URL prefix → filesystem prefix" pairs registered with WordPress.
561 *
562 * We never assume `site_url()` maps to `ABSPATH` (the WordPress root can
563 * live above the document root in Bedrock-style installs, behind a proxy,
564 * or on multisite with mapped domains). Each branch resolves through a
565 * known WP API (plugins, themes, content, includes) and validates that
566 * `realpath()` of the result still lives under the expected base — so a
567 * crafted `..`-laden URL cannot escape into the filesystem.
568 *
569 * @param string $url Asset URL (may be protocol-relative or absolute).
570 * @return string|false Absolute filesystem path on success, false otherwise.
571 */
572 private static function url_to_path( $url ) {
573 if ( ! is_string( $url ) || '' === $url ) {
574 return false;
575 }
576
577 // Drop query string + fragment.
578 $clean = strtok( $url, '?#' );
579
580 // Normalise protocol-relative + scheme variants of the host so we
581 // match regardless of whether the asset URL came in over http/https.
582 $site_host = wp_parse_url( home_url(), PHP_URL_HOST );
583 if ( 0 === strpos( $clean, '//' ) ) {
584 $clean = 'https:' . $clean;
585 }
586 if ( $site_host ) {
587 $asset_host = wp_parse_url( $clean, PHP_URL_HOST );
588 if ( $asset_host && $asset_host !== $site_host ) {
589 return false; // External asset — never touch.
590 }
591 }
592
593 $candidates = array(
594 array( plugins_url(), WP_PLUGIN_DIR ),
595 array( get_stylesheet_directory_uri(), get_stylesheet_directory() ),
596 array( get_template_directory_uri(), get_template_directory() ),
597 array( content_url(), WP_CONTENT_DIR ),
598 array( includes_url(), ABSPATH . WPINC ),
599 );
600
601 // The host check above normalised the HOST but not the SCHEME, and the
602 // prefix match below is a plain string compare — so an https asset URL
603 // never matched an http base and the file silently shipped unminified.
604 // That is not a corner case: WP_CONTENT_URL is derived from a stored
605 // option, `plugins_url()` from another, and a site moved to https
606 // without rewriting every row (or one behind a TLS-terminating proxy
607 // where `is_ssl()` reads false) serves https pages off http-rooted
608 // bases all day. Comparing scheme-less is the whole fix; the host
609 // equality test already did the security work of refusing anything
610 // off-site, and this runs after it.
611 $strip_scheme = static function ( string $value ): string {
612 return (string) preg_replace( '#^https?://#i', '//', $value );
613 };
614 $clean_match = $strip_scheme( $clean );
615
616 foreach ( $candidates as $pair ) {
617 list( $url_base, $path_base ) = $pair;
618 if ( ! $url_base || ! $path_base ) {
619 continue;
620 }
621 $url_base = rtrim( $url_base, '/' );
622 $base_match = $strip_scheme( $url_base );
623 if ( 0 !== strpos( $clean_match, $base_match . '/' ) && $clean_match !== $base_match ) {
624 continue;
625 }
626
627 // Slice the scheme-less pair, not the original. `https://…` and
628 // `http://…` differ by one byte, so an offset taken from the base
629 // as written would cut one character short of (or past) the path
630 // when the two schemes disagree — which is the case this fix
631 // exists for.
632 $relative = ltrim( substr( $clean_match, strlen( $base_match ) ), '/' );
633 $candidate = trailingslashit( $path_base ) . $relative;
634
635 $real_base = realpath( $path_base );
636 $real = realpath( $candidate );
637 if ( ! $real_base || ! $real ) {
638 return false;
639 }
640 // Guard against `..`-traversal: resolved path must stay inside
641 // the registered base.
642 if ( 0 !== strpos( $real, $real_base ) ) {
643 return false;
644 }
645 return $real;
646 }
647
648 return false;
649 }
650
651 private static function cache_path( $key, $type ) {
652 return self::min_dir() . '/' . $key . '.' . $type;
653 }
654
655 private static function ensure_dir( $dir ) {
656 if ( ! file_exists( $dir ) ) {
657 wp_mkdir_p( $dir );
658 Cache::write_silence( $dir );
659 }
660 }
661
662 /**
663 * Clear every minified / combined asset.
664 *
665 * @return int Files removed. Most callers are `add_action` callbacks and
666 * ignore it; `wp xspeed purge` reports it as a line item.
667 */
668 public static function purge_minified() {
669 return self::rmtree_files( self::min_dir() );
670 }
671
672 /**
673 * Recursively delete every file under $dir (and the emptied
674 * subdirectories), keeping $dir itself. The previous glob('$dir/*')
675 * was non-recursive and no-ops on directories, so combined assets in
676 * min/combined/ were never cleared — a purge left a stale
677 * combined-<hash>.css the regenerated page no longer referenced.
678 * (FBS-83114 / FBS-83116)
679 */
680 private static function rmtree_files( string $dir ): int {
681 if ( ! is_dir( $dir ) ) {
682 return 0;
683 }
684 $removed = 0;
685 foreach ( (array) glob( $dir . '/*' ) as $path ) {
686 if ( is_dir( $path ) ) {
687 $removed += self::rmtree_files( $path );
688 @rmdir( $path ); // phpcs:ignore WordPress.WP.AlternativeFunctions.file_system_operations_rmdir, WordPress.PHP.NoSilencedErrors.Discouraged -- best-effort cleanup of our own cache subdir; WP_Filesystem is unavailable on the frontend purge path.
689 continue;
690 }
691 wp_delete_file( $path );
692 ++$removed;
693 }
694 return $removed;
695 }
696 }
697