Improved performance

README.md

@@ -4,7 +4,8 @@ A markdown renderer that supports only a subset of the CommonMark spec in order
 
 ## Features
 
-- Code
+- Code blocks
+- Formatting (bold, italic, monospace)
 - Links
 - Lists
 - Headers
@@ -47,9 +48,9 @@ coverage: 100.0% of statements
 ## Benchmarks
 
 ```
-BenchmarkSmall-12        8109500               145.1 ns/op            32 B/op          1 allocs/op
-BenchmarkMedium-12        556713              1906 ns/op             512 B/op          1 allocs/op
-BenchmarkLarge-12         218116              4588 ns/op            2560 B/op          2 allocs/op
+BenchmarkSmall-12        5986922               187.5 ns/op            32 B/op          1 allocs/op
+BenchmarkMedium-12       1000000              1077 ns/op             512 B/op          1 allocs/op
+BenchmarkLarge-12         255178              4055 ns/op            2560 B/op          2 allocs/op
 ```
 
 ## License

Render.go

@@ -249,36 +249,37 @@ func (r *renderer) closeTables() {
 // writeText converts inline markdown to HTML.
 func (r *renderer) writeText(markdown string) {
 	var (
-		i          = 0
-		tokenStart = 0
-	)
-
-	var (
-		textStart   = -1
-		textEnd     = -1
-		urlStart    = -1
-		codeStart   = -1
-		emStart     = -1
-		strongStart = -1
-		parentheses = 0
+		tokenStart    = 0
+		searchStart   = 0
+		linkTextStart = -1
+		linkTextEnd   = -1
+		urlStart      = -1
+		codeStart     = -1
+		emStart       = -1
+		strongStart   = -1
+		parentheses   = 0
 	)
 
 	for {
-		if i >= len(markdown) {
+		i := strings.IndexAny(markdown[searchStart:], "[]()`*_")
+
+		if i == -1 {
 			r.WriteString(html.EscapeString(markdown[tokenStart:]))
 			return
 		}
 
+		i += searchStart
+		searchStart = i + 1
 		c := markdown[i]
 
 		switch c {
 		case '[':
 			r.WriteString(html.EscapeString(markdown[tokenStart:i]))
 			tokenStart = i
-			textStart = i
+			linkTextStart = i
 
 		case ']':
-			textEnd = i
+			linkTextEnd = i
 
 		case '(':
 			if parentheses == 0 {
@@ -290,8 +291,8 @@ func (r *renderer) writeText(markdown string) {
 		case ')':
 			parentheses--
 
-			if parentheses == 0 && textStart >= 0 && textEnd >= 0 && urlStart >= 0 {
-				linkText := markdown[textStart+1 : textEnd]
+			if parentheses == 0 && linkTextStart >= 0 && linkTextEnd >= 0 && urlStart >= 0 {
+				linkText := markdown[linkTextStart+1 : linkTextEnd]
 				linkURL := markdown[urlStart+1 : i]
 
 				r.WriteString("<a href=\"")
@@ -300,8 +301,8 @@ func (r *renderer) writeText(markdown string) {
 				r.WriteString(html.EscapeString(linkText))
 				r.WriteString("</a>")
 
-				textStart = -1
-				textEnd = -1
+				linkTextStart = -1
+				linkTextEnd = -1
 				urlStart = -1
 
 				tokenStart = i + 1
@@ -329,9 +330,8 @@ func (r *renderer) writeText(markdown string) {
 				r.WriteString(html.EscapeString(markdown[strongStart:i]))
 				r.WriteString("</strong>")
 				strongStart = -1
-
-				i++
-				tokenStart = i + 1
+				tokenStart = i + 2
+				searchStart = tokenStart
 			} else if emStart != -1 {
 				r.WriteString("<em>")
 				r.WriteString(html.EscapeString(markdown[emStart:i]))
@@ -344,8 +344,6 @@ func (r *renderer) writeText(markdown string) {
 				emStart = i + 1
 			}
 		}
-
-		i++
 	}
 }