Repository navigation
A descendant rule with a part mPDF cannot match is applied to the element its first parts name #521
Description
Part of #520 (step 1).
SelectorParser::parseCascadedSelector() stops at the first part of a descendant selector it cannot parse and returns the parts before it (if (!$tag) { break; }, src/Css/SelectorParser.php:152). CssParser::processCssSelector() stores what is left with the depth of the whole selector (src/Css/CssParser.php:291). The shortened rule then passes the depth check in CssMerger::setMergedCss() and is applied to the element its first parts name. On the table path setMergedCss() does not check depth at all.
Measured on gravitypdf at b6a07921, PHP 8.5.4.
| Rule | Treated as | Effect |
|---|---|---|
div p > span {color:red} on <div><p> |
div p |
the p is red |
div p a:hover {color:red} on <div><p> |
div p |
the p text is red |
nav ul li:last-child {color:red} |
nav ul |
the ul is red, so every li inherits it |
table td > span {color:red} on <table><tr><td> |
table td |
the cell is red |
.a p {color:green} .a p > span {color:red} on <div class="a"><p> |
.a p |
red: the shortened rule is stored in the same node as the real one and overrides it |
Framework and CMS stylesheets contain rules of exactly this shape. When only one part is left nothing visible happens (checked with .a > .b), because the properties land where no lookup reads them.
Fix. parseCascadedSelector() returns no levels when any part fails, as parseSimpleSelector() already does, so the rule is dropped as a browser drops what it cannot match. A fix is committed locally as e88dd209 on fix/selector-truncation, based on 973ef247. It merges cleanly onto b6a07921 and makes every row above match a browser. Rebase it and name the branch after this issue.
No upstream issue found. The closest, mpdf#138, renders identically before and after.
Tests. The five rows above, plus div p and .a .b p still applying.
Activity
jakejackson1 commentedon Sep 28, 2026
Completed by #519 (merged as
d660a410).