The composite figure drops its panels wrapper

CHANGELOG.md

@@ -116,8 +116,9 @@ This project uses [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
   from its label's sequence and a panel id resolves `</#id>` as the group
   number plus a letter ("Figure 2a"). An opener carrying a quoted title or
   `[label]` stays a generic container, and groups do not nest. HTML renders the
-  corpus-pinned `carve-figure-group` / `carve-figure-panels` /
-  `carve-figure-panel` shape; the Markdown, plain-text and ANSI targets degrade
+  corpus-pinned flat `carve-figure-group` / `carve-figure-panel` shape (panels
+  directly inside the group figure, per HTML's figure content model and
+  Pandoc's subfigure output); the Markdown, plain-text and ANSI targets degrade
   deterministically; `carve fmt` writes the authored form back; the AST wire
   carries `figure_group` with inline `caption` content; and the HTML importer
   turns the rendered shape back into `::: figure` source.

src/Converter/HtmlToCarve.php

@@ -3769,31 +3769,23 @@ protected function processFigureGroup(DOMElement $node): string
     {
         $attrs = $this->formatBlockAttributesWithoutClass($node, 'carve-figure-group');
 
-        $panelsDiv = null;
+        // FLAT shape: panels and preserved stray content are DIRECT children
+        // of the group figure - no wrapper element - and the group's own
+        // `<figcaption>` is the direct child handled below (a panel's caption
+        // sits inside the panel figure, so it never matches here).
+        $content = '';
         foreach ($node->childNodes as $child) {
+            if ($child instanceof DOMElement && strtolower($child->tagName) === 'figcaption') {
+                continue;
+            }
             if (
                 $child instanceof DOMElement
-                && strtolower($child->tagName) === 'div'
-                && $this->hasClass($child, 'carve-figure-panels')
+                && strtolower($child->tagName) === 'figure'
+                && $this->hasClass($child, 'carve-figure-panel')
             ) {
-                $panelsDiv = $child;
-
-                break;
-            }
-        }
-
-        $content = '';
-        if ($panelsDiv !== null) {
-            foreach ($panelsDiv->childNodes as $child) {
-                if (
-                    $child instanceof DOMElement
-                    && strtolower($child->tagName) === 'figure'
-                    && $this->hasClass($child, 'carve-figure-panel')
-                ) {
-                    $content .= $this->processFigurePanel($child);
-                } else {
-                    $content .= $this->processNode($child);
-                }
+                $content .= $this->processFigurePanel($child);
+            } else {
+                $content .= $this->processNode($child);
             }
         }
         $content = trim($content);

src/Renderer/HtmlRenderer.php

@@ -1667,10 +1667,10 @@ protected static function withLeadingClass(array $attrs, string $leadingClass):
      * A composite figure (PART 9 §4c, markup-carve/carve#1122).
      *
      * The corpus pins the byte shape (318-composite-figures): the group class
-     * leads, the panels div is UNCONDITIONAL - zero panels still wrap the
-     * preserved stray content - and a Figure panel renders as the `<figure>`
-     * its host already produces with `carve-figure-panel` leading its classes.
-     * A table does not render as a figure on its own, so its panel wrapper is
+     * leads, panels and preserved stray content are DIRECT children of the
+     * group figure, and a Figure panel renders as the `<figure>` its host
+     * already produces with `carve-figure-panel` leading its classes. A table
+     * does not render as a figure on its own, so its panel wrapper is
      * explicit and the table keeps its own attributes and its own `<caption>`.
      * No group caption, no trailing `<figcaption>`.
      */
@@ -1680,32 +1680,36 @@ protected function renderFigureGroup(FigureGroup $node): string
             self::withLeadingClass($this->getRenderableAttributes($node), 'carve-figure-group'),
         );
 
-        $inner = '';
+        // FLAT: panels and preserved stray content nest DIRECTLY inside the
+        // group figure, the group caption last. HTML's figure content model is
+        // one figcaption first-or-last plus flow content, and a figure is
+        // itself flow content, so the wrapper div added nothing the element
+        // does not already provide - and Pandoc's subfigure HTML output has
+        // the same flat shape.
+        $body = '';
         foreach ($node->getChildren() as $child) {
             if ($child instanceof Figure) {
-                $inner .= $this->renderFigure($child, 'carve-figure-panel');
+                $body .= $this->renderFigure($child, 'carve-figure-panel');
             } elseif ($child instanceof Table) {
                 $table = rtrim($this->renderTable($child), "\n");
-                $inner .= "<figure class=\"carve-figure-panel\">\n"
+                $body .= "<figure class=\"carve-figure-panel\">\n"
                     . $this->indentBlock($table, 2) . "\n</figure>\n";
             } else {
-                $inner .= rtrim($this->renderNode($child), "\n") . "\n";
+                $body .= rtrim($this->renderNode($child), "\n") . "\n";
             }
         }
 
-        $body = "<div class=\"carve-figure-panels\">\n";
-        $inner = rtrim($inner, "\n");
-        if ($inner !== '') {
-            $body .= $this->indentBlock($inner, 2) . "\n";
-        }
-        $body .= "</div>\n";
-
         $caption = $node->getCaption();
         if ($caption !== null) {
             $body .= '<figcaption>' . $this->renderChildren($caption) . "</figcaption>\n";
         }
 
-        return '<figure' . $attrs . ">\n" . $this->indentBlock(rtrim($body, "\n"), 2) . "\n</figure>\n";
+        $body = rtrim($body, "\n");
+        if ($body === '') {
+            return '<figure' . $attrs . ">\n</figure>\n";
+        }
+
+        return '<figure' . $attrs . ">\n" . $this->indentBlock($body, 2) . "\n</figure>\n";
     }
 
     protected function renderTable(Table $node): string

tests/TestCase/Parser/ABareFigureFenceIsACompositeFigureTest.php

@@ -56,6 +56,24 @@ public function testAnEmptyGroupIsAValidParseToo(): void
         $this->assertSame([], $node->getChildren());
     }
 
+    public function testAnEmptyGroupRendersTheBareContainerEmptyBodyShape(): void
+    {
+        // The oracle keeps the PART 10 §4 exception the BARE div takes: an
+        // empty uncaptioned group closes on the next line, no blank body line.
+        $this->assertSame(
+            "<figure class=\"carve-figure-group\">\n</figure>\n",
+            (new CarveConverter())->convert("::: figure\n:::\n"),
+        );
+    }
+
+    public function testAnEmptyCaptionedGroupHoldsOnlyItsFigcaption(): void
+    {
+        $this->assertSame(
+            "<figure class=\"carve-figure-group\">\n  <figcaption>Figure 1: G</figcaption>\n</figure>\n",
+            (new CarveConverter())->convert("::: figure\n:::\n^ Figure #: G\n"),
+        );
+    }
+
     public function testAQuotedTitleKeepsTheOpenerAGenericContainer(): void
     {
         // `figure_group` has no title slot BY DESIGN (§4c): the group's one