Improve footnote handling

- Footnotes separator rather than headline to get around i18n
- Warn on footnote redefinition
- Do not export footnote definitions at point of definition, only in the
  footnote section.
- Do not automatically exclude Footnotes section to get around possibly hiding
  other content of such a section - and i18n.
  The user has the choice of explicitly hiding the section via a :noexport:
  tag.

and some other refactoring

etc/generate-fixtures

@@ -1,6 +1,7 @@
 #!/bin/bash
 
 for org_file in org/testdata/*.org; do
+    echo $org_file
     ./go-org $org_file html > org/testdata/$(basename $org_file .org).html
     ./go-org $org_file org > org/testdata/$(basename $org_file .org).pretty_org
 done

org/document.go

@@ -14,7 +14,7 @@ type Document struct {
 	Path                string
 	tokens              []token
 	Nodes               []Node
-	Footnotes           *Footnotes
+	Footnotes           Footnotes
 	StatusKeywords      []string
 	MaxEmphasisNewLines int
 	AutoLink            bool
@@ -72,7 +72,7 @@ func FrontMatterHandler(fm FrontMatter, k, v string) error {
 
 func NewDocument() *Document {
 	return &Document{
-		Footnotes: &Footnotes{
+		Footnotes: Footnotes{
 			Title:       "Footnotes",
 			Definitions: map[string]*FootnoteDefinition{},
 		},
@@ -222,6 +222,16 @@ func (d *Document) parseMany(i int, stop stopFn) (int, []Node) {
 	return i - start, nodes
 }
 
+func (d *Document) addFootnote(name string, definition *FootnoteDefinition) {
+	if definition != nil {
+		if _, exists := d.Footnotes.Definitions[name]; exists {
+			d.Log.Printf("Footnote [fn:%s] redefined! %#v", name, definition)
+		}
+		d.Footnotes.Definitions[name] = definition
+	}
+	d.Footnotes.addOrder = append(d.Footnotes.addOrder, name)
+}
+
 func tokenize(line string) token {
 	for _, lexFn := range lexFns {
 		if token, ok := lexFn(line); ok {

org/footnote.go

@@ -35,17 +35,10 @@ func (d *Document) parseFootnoteDefinition(i int, parentStop stopFn) (int, Node)
 	}
 	consumed, nodes := d.parseMany(i, stop)
 	definition := FootnoteDefinition{name, nodes, false}
-	d.Footnotes.add(name, &definition)
+	d.addFootnote(name, &definition)
 	return consumed, definition
 }
 
-func (fs *Footnotes) add(name string, definition *FootnoteDefinition) {
-	if definition != nil {
-		fs.Definitions[name] = definition
-	}
-	fs.addOrder = append(fs.addOrder, name)
-}
-
 func (fs *Footnotes) Ordered() []FootnoteDefinition {
 	m := map[string]bool{}
 	definitions, inlineDefinitions := []FootnoteDefinition{}, []FootnoteDefinition{}

org/html.go

@@ -13,11 +13,10 @@ import (
 
 type HTMLWriter struct {
 	stringBuilder
-	HighlightCodeBlock    func(source, lang string) string
+	HighlightCodeBlock func(source, lang string) string
-	FootnotesHeadingTitle string
+	htmlEscape         bool
-	htmlEscape            bool
+	excludeTags        []string
-	excludeTags           []string
+	log                *log.Logger
-	log                   *log.Logger
 }
 
 var emphasisTags = map[string][]string{
@@ -45,8 +44,7 @@ var listItemStatuses = map[string]string{
 
 func NewHTMLWriter() *HTMLWriter {
 	return &HTMLWriter{
-		htmlEscape:            true,
+		htmlEscape: true,
-		FootnotesHeadingTitle: "Footnotes",
 		HighlightCodeBlock: func(source, lang string) string {
 			return fmt.Sprintf("%s\n<pre>\n%s\n</pre>\n</div>", `<div class="highlight">`, html.EscapeString(source))
 		},
@@ -95,7 +93,7 @@ func (w *HTMLWriter) writeNodes(ns ...Node) {
 			continue
 
 		case FootnoteDefinition:
-			w.writeFootnoteDefinition(n)
+			continue
 
 		case List:
 			w.writeList(n)
@@ -191,24 +189,19 @@ func (w *HTMLWriter) writeFootnoteDefinition(f FootnoteDefinition) {
 }
 
 func (w *HTMLWriter) writeFootnotes(d *Document) {
-	fs := d.Footnotes
+	if len(d.Footnotes.Definitions) == 0 {
-	if len(fs.Definitions) == 0 {
 		return
 	}
 	w.WriteString(`<div class="footnotes">` + "\n")
-	w.WriteString(`<h1 class="footnotes-title">` + fs.Title + `</h1>` + "\n")
+	w.WriteString(`<hr class="footnotes-separatator">` + "\n")
 	w.WriteString(`<div class="footnote-definitions">` + "\n")
 	for _, definition := range d.Footnotes.Ordered() {
-		w.writeNodes(definition)
+		w.writeFootnoteDefinition(definition)
 	}
 	w.WriteString("</div>\n</div>\n")
 }
 
 func (w *HTMLWriter) writeHeadline(h Headline) {
-	title := w.nodesAsString(h.Title...)
-	if h.Lvl == 1 && title == w.FootnotesHeadingTitle {
-		return
-	}
 	for _, excludeTag := range w.excludeTags {
 		for _, tag := range h.Tags {
 			if excludeTag == tag {
@@ -230,7 +223,7 @@ func (w *HTMLWriter) writeHeadline(h Headline) {
 		w.WriteString(fmt.Sprintf(`<span class="priority">[%s]</span>`, h.Priority) + "\n")
 	}
 
-	w.WriteString(title)
+	w.writeNodes(h.Title...)
 	if len(h.Tags) != 0 {
 		tags := make([]string, len(h.Tags))
 		for i, tag := range h.Tags {
@@ -337,7 +330,7 @@ func (w *HTMLWriter) writeDescriptiveListItem(di DescriptiveListItem) {
 }
 
 func (w *HTMLWriter) writeParagraph(p Paragraph) {
-	if isEmptyLineParagraph(p) {
+	if len(p.Children) == 0 {
 		return
 	}
 	w.WriteString("<p>")

org/inline.go

@@ -157,7 +157,7 @@ func (d *Document) parseFootnoteReference(input string, start int) (int, Node) {
 		link := FootnoteLink{name, nil}
 		if definition != "" {
 			link.Definition = &FootnoteDefinition{name, []Node{Paragraph{d.parseInline(definition)}}, true}
-			d.Footnotes.add(name, link.Definition)
+			d.addFootnote(name, link.Definition)
 		}
 		return len(m[0]), link
 	}

org/org.go

@@ -3,6 +3,7 @@ package org
 import (
 	"fmt"
 	"strings"
+	"unicode"
 	"unicode/utf8"
 )
 
@@ -175,10 +176,11 @@ func (w *OrgWriter) writePropertyDrawer(d PropertyDrawer) {
 
 func (w *OrgWriter) writeFootnoteDefinition(f FootnoteDefinition) {
 	w.WriteString(fmt.Sprintf("[fn:%s]", f.Name))
-	if !(len(f.Children) >= 1 && isEmptyLineParagraph(f.Children[0])) {
+	content := w.nodesAsString(f.Children...)
+	if content != "" && !unicode.IsSpace(rune(content[0])) {
 		w.WriteString(" ")
 	}
-	w.writeNodes(f.Children...)
+	w.WriteString(content)
 }
 
 func (w *OrgWriter) writeParagraph(p Paragraph) {

org/testdata/footnotes.html

@@ -17,11 +17,43 @@ further references to the same footnote should not <sup class="footnote-referenc
 inline footnotes are also supported via <sup class="footnote-reference"><a id="footnote-reference-2" href="#footnote-2">2</a></sup>.
 </p>
 </li>
+<li>
+<p>
+Footnote definitions are not printed where they appear.
+Rather, they are gathered and exported at the end of the document in the footnote section. <sup class="footnote-reference"><a id="footnote-reference-4" href="#footnote-4">4</a></sup>
+</p>
+</li>
 </ul>
+<h1>
+Footnotes
+</h1>
+<p>
+Please note that the footnotes section is not automatically excluded from the export like in emacs. <sup class="footnote-reference"><a id="footnote-reference-7" href="#footnote-7">7</a></sup>
+</p>
+<p>
+this is not part of <sup class="footnote-reference"><a id="footnote-reference-7" href="#footnote-7">7</a></sup> anymore as there are 2 blank lines in between!
+</p>
 <div class="footnotes">
-<h1 class="footnotes-title">Footnotes</h1>
+<hr class="footnotes-separatator">
 <div class="footnote-definitions">
 <div class="footnote-definition">
+<sup id="footnote-4"><a href="#footnote-reference-4">4</a></sup>
+<div class="footnote-body">
+<p>
+so this definition will not be at the end of this section in the exported document.
+Rather, it will be somewhere down below in the footnotes section.
+</p>
+</div>
+</div>
+<div class="footnote-definition">
+<sup id="footnote-5"><a href="#footnote-reference-5">5</a></sup>
+<div class="footnote-body">
+<p>
+another unused footnote (this definition overwrites the previous definition of <code class="verbatim">fn:5</code>)
+</p>
+</div>
+</div>
+<div class="footnote-definition">
 <sup id="footnote-1"><a href="#footnote-reference-1">1</a></sup>
 <div class="footnote-body">
 <p>
@@ -83,22 +115,6 @@ and tables
 </div>
 </div>
 <div class="footnote-definition">
-<sup id="footnote-4"><a href="#footnote-reference-4">4</a></sup>
-<div class="footnote-body">
-<p>
-another unused footnote
-</p>
-</div>
-</div>
-<div class="footnote-definition">
-<sup id="footnote-5"><a href="#footnote-reference-5">5</a></sup>
-<div class="footnote-body">
-<p>
-another unused footnote
-</p>
-</div>
-</div>
-<div class="footnote-definition">
 <sup id="footnote-6"><a href="#footnote-reference-6">6</a></sup>
 <div class="footnote-body">
 <p>
@@ -108,6 +124,15 @@ This shouldn&#39;t happen when the definition line and the line after that are e
 </div>
 </div>
 <div class="footnote-definition">
+<sup id="footnote-7"><a href="#footnote-reference-7">7</a></sup>
+<div class="footnote-body">
+<p>
+There&#39;s multiple reasons for that. Among others, doing so requires i18n (to recognize the section) and silently
+hides content before and after the footnotes.
+</p>
+</div>
+</div>
+<div class="footnote-definition">
 <sup id="footnote-2"><a href="#footnote-reference-2">2</a></sup>
 <div class="footnote-body">
 <p>

org/testdata/footnotes.org

@@ -2,8 +2,17 @@
 - normal footnote reference [fn:1] [fn:6]
 - further references to the same footnote should not [fn:1] render duplicates in the footnote list
 - inline footnotes are also supported via [fn:2:the inline footnote definition].
+- Footnote definitions are not printed where they appear.
+  Rather, they are gathered and exported at the end of the document in the footnote section. [fn:4]
 
+[fn:4] so this definition will not be at the end of this section in the exported document.
+Rather, it will be somewhere down below in the footnotes section.
+
+[fn:5] this definition will also not be exported here - not only that, it will be overwritten by a definition
+of the same name later on in the document. That will log a warning but carry on nonetheless.
 * Footnotes
+Please note that the footnotes section is not automatically excluded from the export like in emacs. [fn:7]
+
 [fn:1] https://www.example.com
 - footnotes can contain *markup*
 - and other elements
@@ -18,11 +27,18 @@
 
 [fn:3] [[http://example.com/unused-footnote][example.com/unused-footnote]]
 
-[fn:4] another unused footnote
+[fn:5] another unused footnote (this definition overwrites the previous definition of =fn:5=)
-
-[fn:5] another unused footnote
 
 [fn:6]
 
 Footnotes break after two consecutive empty lines - just like paragraphs - see https://orgmode.org/worg/dev/org-syntax.html.
 This shouldn't happen when the definition line and the line after that are empty.
+
+
+[fn:7]
+There's multiple reasons for that. Among others, doing so requires i18n (to recognize the section) and silently
+hides content before and after the footnotes.
+
+
+
+this is not part of [fn:7] anymore as there are 2 blank lines in between!

org/testdata/footnotes.pretty_org

@@ -2,8 +2,17 @@
 - normal footnote reference [fn:1] [fn:6]
 - further references to the same footnote should not [fn:1] render duplicates in the footnote list
 - inline footnotes are also supported via [fn:2:the inline footnote definition].
+- Footnote definitions are not printed where they appear.
+  Rather, they are gathered and exported at the end of the document in the footnote section. [fn:4]
 
+[fn:4] so this definition will not be at the end of this section in the exported document.
+Rather, it will be somewhere down below in the footnotes section.
+
+[fn:5] this definition will also not be exported here - not only that, it will be overwritten by a definition
+of the same name later on in the document. That will log a warning but carry on nonetheless.
 * Footnotes
+Please note that the footnotes section is not automatically excluded from the export like in emacs. [fn:7]
+
 [fn:1] https://www.example.com
 - footnotes can contain *markup*
 - and other elements
@@ -18,11 +27,18 @@
 
 [fn:3] [[http://example.com/unused-footnote][example.com/unused-footnote]]
 
-[fn:4] another unused footnote
+[fn:5] another unused footnote (this definition overwrites the previous definition of =fn:5=)
-
-[fn:5] another unused footnote
 
 [fn:6]
 
 Footnotes break after two consecutive empty lines - just like paragraphs - see https://orgmode.org/worg/dev/org-syntax.html.
 This shouldn't happen when the definition line and the line after that are empty.
+
+
+[fn:7]
+There's multiple reasons for that. Among others, doing so requires i18n (to recognize the section) and silently
+hides content before and after the footnotes.
+
+
+
+this is not part of [fn:7] anymore as there are 2 blank lines in between!

org/testdata/misc.html

@@ -359,8 +359,11 @@ When inserting an image link like <img src="/home/amos/Pictures/Screenshots/img-
   (ansi-term))
 </pre>
 </div>
+<h1>
+Footnotes
+</h1>
 <div class="footnotes">
-<h1 class="footnotes-title">Footnotes</h1>
+<hr class="footnotes-separatator">
 <div class="footnote-definitions">
 <div class="footnote-definition">
 <sup id="footnote-1"><a href="#footnote-reference-1">1</a></sup>

org/util.go

@@ -11,11 +11,6 @@ func isSecondBlankLine(d *Document, i int) bool {
 	return false
 }
 
-func isEmptyLineParagraph(n Node) bool {
-	p, ok := n.(Paragraph)
-	return ok && len(p.Children) == 0
-}
-
 func isImageOrVideoLink(n Node) bool {
 	if l, ok := n.(RegularLink); ok && l.Kind() == "video" || l.Kind() == "image" {
 		return true