From 8e009702c2805f5e99de63c36909e7d81b58088e Mon Sep 17 00:00:00 2001
From: Eduard Urbach <admin@akyoto.dev>
Date: Mon, 1 Apr 2024 20:04:20 +0200
Subject: [PATCH] Implemented lists

---
 README.md      |  3 ++-
 Render.go      | 42 +++++++++++++++++++++++++++++++++++++-----
 Render_test.go |  9 +++++++++
 3 files changed, 48 insertions(+), 6 deletions(-)

diff --git a/README.md b/README.md
index b59879e..c5f42be 100644
--- a/README.md
+++ b/README.md
@@ -5,6 +5,7 @@ Markdown renderer.
 ## Features
 
 - Links
+- Lists
 - Headers
 - Paragraphs
 - Quotes
@@ -37,7 +38,7 @@ coverage: 100.0% of statements
 ## Benchmarks
 
 ```
-BenchmarkSmall-12        2425053               492.8 ns/op           248 B/op          5 allocs/op
+BenchmarkSmall-12        2585194               462.4 ns/op           248 B/op          5 allocs/op
 ```
 
 ## License
diff --git a/Render.go b/Render.go
index 1447a87..d13efe2 100644
--- a/Render.go
+++ b/Render.go
@@ -14,6 +14,7 @@ type renderer struct {
 	out            strings.Builder
 	paragraphLevel int
 	quoteLevel     int
+	listLevel      int
 }
 
 // Render creates HTML from the supplied markdown text.
@@ -26,7 +27,7 @@ func Render(markdown string) string {
 
 	for {
 		if i > len(markdown) {
-			r.closeParagraphs()
+			r.closeAll()
 
 			for range r.quoteLevel {
 				r.out.WriteString("</blockquote>")
@@ -72,8 +73,14 @@ func (r *renderer) processLine(line string) {
 
 	r.quoteLevel = newQuoteLevel
 
-	if strings.HasPrefix(line, "#") {
-		r.closeParagraphs()
+	if len(line) == 0 {
+		r.closeAll()
+		return
+	}
+
+	switch line[0] {
+	case '#':
+		r.closeAll()
 		space := strings.IndexByte(line, ' ')
 
 		if space > 0 && space <= 6 {
@@ -83,10 +90,19 @@ func (r *renderer) processLine(line string) {
 		}
 
 		return
-	}
 
-	if len(line) == 0 {
+	case '-', '*':
 		r.closeParagraphs()
+		line = strings.TrimSpace(line[1:])
+
+		if r.listLevel == 0 {
+			r.out.WriteString("<ul>")
+			r.listLevel++
+		}
+
+		r.out.WriteString("<li>")
+		r.writeText(line)
+		r.out.WriteString("</li>")
 		return
 	}
 
@@ -101,6 +117,12 @@ func (r *renderer) processLine(line string) {
 	r.writeText(line)
 }
 
+// closeAll closes all open tags.
+func (r *renderer) closeAll() {
+	r.closeLists()
+	r.closeParagraphs()
+}
+
 // closeParagraphs closes open paragraphs.
 func (r *renderer) closeParagraphs() {
 	for range r.paragraphLevel {
@@ -110,6 +132,15 @@ func (r *renderer) closeParagraphs() {
 	r.paragraphLevel = 0
 }
 
+// closeLists closes open lists.
+func (r *renderer) closeLists() {
+	for range r.listLevel {
+		r.out.WriteString("</ul>")
+	}
+
+	r.listLevel = 0
+}
+
 // writeText converts inline markdown to HTML.
 func (r *renderer) writeText(markdown string) {
 	var (
@@ -170,6 +201,7 @@ func (r *renderer) writeText(markdown string) {
 	}
 }
 
+// sanitizeURL makes a URL safe to use as the value for a `href` attribute.
 func sanitizeURL(linkURL string) string {
 	linkURL = strings.TrimSpace(linkURL)
 
diff --git a/Render_test.go b/Render_test.go
index 4ccecaa..95be167 100644
--- a/Render_test.go
+++ b/Render_test.go
@@ -38,6 +38,12 @@ func TestLink(t *testing.T) {
 	assert.Equal(t, markdown.Render("Prefix [text](https://example.com/) suffix."), "<p>Prefix <a href=\"https://example.com/\">text</a> suffix.</p>")
 }
 
+func TestList(t *testing.T) {
+	assert.Equal(t, markdown.Render("- Entry"), "<ul><li>Entry</li></ul>")
+	assert.Equal(t, markdown.Render("- Entry 1\n- Entry 2"), "<ul><li>Entry 1</li><li>Entry 2</li></ul>")
+	assert.Equal(t, markdown.Render("- Entry 1\n- Entry 2\n- Entry 3"), "<ul><li>Entry 1</li><li>Entry 2</li><li>Entry 3</li></ul>")
+}
+
 func TestQuote(t *testing.T) {
 	assert.Equal(t, markdown.Render("> Line"), "<blockquote><p>Line</p></blockquote>")
 	assert.Equal(t, markdown.Render("> Line 1\n> Line 2"), "<blockquote><p>Line 1 Line 2</p></blockquote>")
@@ -51,6 +57,9 @@ func TestCombined(t *testing.T) {
 	assert.Equal(t, markdown.Render("# Header\nLine 1.\nLine 2.\nLine 3."), "<h1>Header</h1><p>Line 1. Line 2. Line 3.</p>")
 	assert.Equal(t, markdown.Render("# Header 1\nLine 1.\n# Header 2\nLine 2."), "<h1>Header 1</h1><p>Line 1.</p><h1>Header 2</h1><p>Line 2.</p>")
 	assert.Equal(t, markdown.Render("# [Header Link](https://example.com/)"), "<h1><a href=\"https://example.com/\">Header Link</a></h1>")
+	assert.Equal(t, markdown.Render("# Title\n\n- Entry 1\n- Entry 2\n\nText."), "<h1>Title</h1><ul><li>Entry 1</li><li>Entry 2</li></ul><p>Text.</p>")
+	assert.Equal(t, markdown.Render("- Entry\n# Header"), "<ul><li>Entry</li></ul><h1>Header</h1>")
+	assert.Equal(t, markdown.Render("> - Entry\n> # Header"), "<blockquote><ul><li>Entry</li></ul><h1>Header</h1></blockquote>")
 }
 
 func TestSecurity(t *testing.T) {