Carry a label text carrier's case onto the label caption

php-transformer/composer.json

@@ -194,6 +194,7 @@
       "php tests/unit/site-marker-document-scan.php",
       "php tests/unit/form-offscreen-submit-presenter.php",
       "php tests/unit/form-submit-caption-box.php",
+      "php tests/unit/form-label-carrier-case.php",
       "php tests/unit/runtime-declarations-streaming-hash.php",
       "php tests/unit/external-metric-declarations.php",
       "php tests/unit/runtime-script-evidence-analyzer.php",

php-transformer/src/HtmlToBlocks/Style/FormPresentationGraphBuilder.php

@@ -32,12 +32,11 @@ final class FormPresentationGraphBuilder
     /** Authored values such as system font stacks exceed a few hundred bytes; bound like selectors and conditions. */
     private const MAX_STYLE_VALUE_BYTES = 1024;
     private const MAX_DIAGNOSTICS = 32;
-    /** The text properties a label role reads from its text carrier when the label declares none itself. */
+    /**
+     * The inherited text properties a label or button caption reads from its
+     * text carrier when it declares none itself, including the caption's case.
+     */
     private const TYPOGRAPHY_PROPERTIES = array(
-        'color', 'font', 'font-family', 'font-size', 'font-weight', 'letter-spacing', 'line-height',
-    );
-    /** A button caption carrier also sets the caption's case. */
-    private const CAPTION_PROPERTIES = array(
         'color', 'font', 'font-family', 'font-size', 'font-weight', 'letter-spacing', 'line-height', 'text-transform',
     );
     /** A block-level caption carrier fills its button, so its padding sizes the button box. */
@@ -743,7 +742,7 @@ private static function assertRole(mixed $role, ?array $condition, bool $allowEm
      */
     private function carrierTypography(array $roles, DOMElement $label, array $rules, array $customPropertyRules, array $labelConditional = array(), bool $captionBox = false): array
     {
-        $properties = array_flip(array() === $roles ? self::CAPTION_PROPERTIES : self::TYPOGRAPHY_PROPERTIES);
+        $properties = array_flip(self::TYPOGRAPHY_PROPERTIES);
         $excluded = array_values(array_filter(
             array( $roles['control'] ?? null, $roles['required_marker'] ?? null ),
             static fn (mixed $element): bool => $element instanceof DOMElement

php-transformer/tests/unit/form-label-carrier-case.php

@@ -0,0 +1,57 @@
+<?php
+declare(strict_types=1);
+
+/**
+ * A label whose text is painted by an inner carrier — `<label class="field">
+ * <span class="field__label">Name</span><input></label>` — takes that text's
+ * case from the carrier, the same way it takes the carrier's font and color.
+ * `text-transform` is an inherited text property, so a provider label that
+ * renders the caption directly must keep it, and an in-form heading that
+ * inherits it from an ancestor keeps it too.
+ */
+
+require dirname(__DIR__, 2) . '/vendor/autoload.php';
+
+use Automattic\BlocksEngine\PhpTransformer\HtmlToBlocks\Style\FormPresentationGraphBuilder;
+
+$failures = 0;
+$passes = 0;
+$assert = static function (bool $ok, string $message, string $detail = '') use (&$failures, &$passes): void {
+    if ( $ok ) {
+        ++$passes;
+        return;
+    }
+    ++$failures;
+    fwrite(STDERR, 'FAIL: ' . $message . ( '' !== $detail ? ' - ' . $detail : '' ) . PHP_EOL);
+};
+
+$document = static function (string $body): DOMDocument {
+    $document = new DOMDocument();
+    $document->loadHTML('<?xml encoding="utf-8" ?><body>' . $body . '</body>', LIBXML_NOERROR | LIBXML_NOWARNING);
+    return $document;
+};
+$label = static function (string $css) use ($document): array {
+    $form = $document('<form class="f" method="post"><label class="field"><span class="field__label">Name</span><input type="text" name="name"></label><button type="submit">Send</button></form>')->getElementsByTagName('form')->item(0);
+    $graph = (new FormPresentationGraphBuilder())->build($form, array(), $css);
+    return array( 'styles' => array_column($graph['controls'], null, 'index')[0]['label']['styles'] ?? array(), 'variants' => $graph['variants'] ?? array() );
+};
+
+$carrier = $label('.field { display: flex; flex-direction: column; } .field__label { font-size: .72rem; letter-spacing: .14em; text-transform: uppercase; }');
+$assert('uppercase' === ($carrier['styles']['text_transform'] ?? null) && '.14em' === ($carrier['styles']['letter_spacing'] ?? null), 'the label text carrier sets the caption case alongside its typography', json_encode($carrier['styles']));
+
+$own = $label('.field { text-transform: lowercase; } .field__label { text-transform: uppercase; }');
+$assert('uppercase' === ($own['styles']['text_transform'] ?? null), 'the carrier case wins over the label case for the text it paints', json_encode($own['styles']));
+
+$responsive = $label('.field__label { text-transform: none; } @media (min-width: 600px) { .field__label { text-transform: uppercase; } }');
+$patches = array_map(static fn (array $variant): array => $variant['style_patch'] ?? array(), array_filter($responsive['variants'], static fn (array $variant): bool => 0 === ($variant['index'] ?? null) && 'label' === ($variant['role'] ?? null)));
+$assert('none' === ($responsive['styles']['text_transform'] ?? null) && in_array('uppercase', array_column($patches, 'text_transform'), true), 'a conditional carrier case becomes a label variant', json_encode(array( $responsive['styles'], $patches )));
+
+$heading = $document('<form class="f" method="post"><div class="eyebrow"><p class="copy">Write to us</p></div><input type="text" name="name"></form>')->getElementsByTagName('p')->item(0);
+$inherited = (new FormPresentationGraphBuilder())->buildElement($heading, array(), '.eyebrow { text-transform: uppercase; }');
+$assert('uppercase' === ($inherited['styles']['text_transform'] ?? null), 'in-form copy inherits its case from the nearest declaring ancestor', json_encode($inherited));
+
+if ( 0 < $failures ) {
+    fwrite(STDERR, "form label carrier case FAILED: {$passes} passed, {$failures} failed\n");
+    exit(1);
+}
+echo "form label carrier case passed: {$passes} assertions\n";