markup/goldmark: Add removeSurroundingParagraph for Markdown images

* Removes any surrounding paragraph nodes
* And transfers any attributes from the surrounding paragraph down to the image node
* Adds IsBlock and Ordinal (zero based) field to the image context passed to the image render hooks

IsBlock is set to true if `wrapStandAloneImageWithinParagraph = false` and  the image's parent node has only one child.

Closes #8362
Fixes #10492
Fixes #10494
Fixes #10501

markup/goldmark/render_hooks.go

@@ -20,6 +20,7 @@ import (
 	"github.com/gohugoio/hugo/common/types/hstring"
 	"github.com/gohugoio/hugo/markup/converter/hooks"
 	"github.com/gohugoio/hugo/markup/goldmark/goldmark_config"
+	"github.com/gohugoio/hugo/markup/goldmark/images"
 	"github.com/gohugoio/hugo/markup/goldmark/internal/render"
 	"github.com/gohugoio/hugo/markup/internal/attributes"
 
@@ -52,16 +53,13 @@ type linkContext struct {
 	title       string
 	text        hstring.RenderedString
 	plainText   string
+	*attributes.AttributesHolder
 }
 
 func (ctx linkContext) Destination() string {
 	return ctx.destination
 }
 
-func (ctx linkContext) Resolved() bool {
-	return false
-}
-
 func (ctx linkContext) Page() any {
 	return ctx.page
 }
@@ -78,6 +76,20 @@ func (ctx linkContext) Title() string {
 	return ctx.title
 }
 
+type imageLinkContext struct {
+	linkContext
+	ordinal int
+	isBlock bool
+}
+
+func (ctx imageLinkContext) IsBlock() bool {
+	return ctx.isBlock
+}
+
+func (ctx imageLinkContext) Ordinal() int {
+	return ctx.ordinal
+}
+
 type headingContext struct {
 	page      any
 	level     int
@@ -151,14 +163,36 @@ func (r *hookedRenderer) renderImage(w util.BufWriter, source []byte, node ast.N
 	text := ctx.Buffer.Bytes()[pos:]
 	ctx.Buffer.Truncate(pos)
 
+	var (
+		isBlock bool
+		ordinal int
+	)
+	if b, ok := n.AttributeString(images.AttrIsBlock); ok && b.(bool) {
+		isBlock = true
+	}
+	if n, ok := n.AttributeString(images.AttrOrdinal); ok {
+		ordinal = n.(int)
+	}
+
+	// We use the attributes to signal from the parser whether the image is in
+	// a block context or not.
+	// We may find a better way to do that, but for now, we'll need to remove any
+	// internal attributes before rendering.
+	attrs := r.filterInternalAttributes(n.Attributes())
+
 	err := lr.RenderLink(
 		w,
-		linkContext{
-			page:        ctx.DocumentContext().Document,
-			destination: string(n.Destination),
-			title:       string(n.Title),
-			text:        hstring.RenderedString(text),
-			plainText:   string(n.Text(source)),
+		imageLinkContext{
+			linkContext: linkContext{
+				page:             ctx.DocumentContext().Document,
+				destination:      string(n.Destination),
+				title:            string(n.Title),
+				text:             hstring.RenderedString(text),
+				plainText:        string(n.Text(source)),
+				AttributesHolder: attributes.New(attrs, attributes.AttributesOwnerGeneral),
+			},
+			ordinal: ordinal,
+			isBlock: isBlock,
 		},
 	)
 
@@ -167,6 +201,17 @@ func (r *hookedRenderer) renderImage(w util.BufWriter, source []byte, node ast.N
 	return ast.WalkContinue, err
 }
 
+func (r *hookedRenderer) filterInternalAttributes(attrs []ast.Attribute) []ast.Attribute {
+	n := 0
+	for _, x := range attrs {
+		if !bytes.HasPrefix(x.Name, []byte(internalAttrPrefix)) {
+			attrs[n] = x
+			n++
+		}
+	}
+	return attrs[:n]
+}
+
 // Fall back to the default Goldmark render funcs. Method below borrowed from:
 // https://github.com/yuin/goldmark/blob/b611cd333a492416b56aa8d94b04a67bf0096ab2/renderer/html/html.go#L404
 func (r *hookedRenderer) renderImageDefault(w util.BufWriter, source []byte, node ast.Node, entering bool) (ast.WalkStatus, error) {
@@ -186,6 +231,10 @@ func (r *hookedRenderer) renderImageDefault(w util.BufWriter, source []byte, nod
 		r.Writer.Write(w, n.Title)
 		_ = w.WriteByte('"')
 	}
+	if n.Attributes() != nil {
+		attrs := r.filterInternalAttributes(n.Attributes())
+		attributes.RenderASTAttributes(w, attrs...)
+	}
 	if r.XHTML {
 		_, _ = w.WriteString(" />")
 	} else {
@@ -224,11 +273,12 @@ func (r *hookedRenderer) renderLink(w util.BufWriter, source []byte, node ast.No
 	err := lr.RenderLink(
 		w,
 		linkContext{
-			page:        ctx.DocumentContext().Document,
-			destination: string(n.Destination),
-			title:       string(n.Title),
-			text:        hstring.RenderedString(text),
-			plainText:   string(n.Text(source)),
+			page:             ctx.DocumentContext().Document,
+			destination:      string(n.Destination),
+			title:            string(n.Title),
+			text:             hstring.RenderedString(text),
+			plainText:        string(n.Text(source)),
+			AttributesHolder: attributes.Empty,
 		},
 	)
 
@@ -292,10 +342,11 @@ func (r *hookedRenderer) renderAutoLink(w util.BufWriter, source []byte, node as
 	err := lr.RenderLink(
 		w,
 		linkContext{
-			page:        ctx.DocumentContext().Document,
-			destination: url,
-			text:        hstring.RenderedString(label),
-			plainText:   label,
+			page:             ctx.DocumentContext().Document,
+			destination:      url,
+			text:             hstring.RenderedString(label),
+			plainText:        label,
+			AttributesHolder: attributes.Empty,
 		},
 	)