refactor syntax highlighting to be blank by default

lets you decide in the theme
apex · Jan 25, 2018 · f1a610f · f1a610f
1 parent edaa6e4
commit f1a610f
Show file tree

Hide file tree

Showing 4 changed files with 127 additions and 106 deletions.
diff --git a/html.go b/html.go
@@ -1,16 +1,11 @@
 package static
 
 import (
-	"bytes"
 	"io"
 	"strconv"
 	"strings"
 
 	dom "github.com/PuerkitoBio/goquery"
-	"github.com/alecthomas/chroma"
-	"github.com/alecthomas/chroma/formatters/html"
-	"github.com/alecthomas/chroma/lexers"
-	"github.com/alecthomas/chroma/styles"
 	snakecase "github.com/segmentio/go-snakecase"
 )
 
@@ -78,72 +73,3 @@ func HeadingAnchors(r io.Reader) io.ReadCloser {
 
 	return pr
 }
-
-// SyntaxHighlight returns a reader with HTML code prettified with chroma
-func SyntaxHighlight(r io.Reader) io.ReadCloser {
-	pr, pw := io.Pipe()
-	go func() {
-		doc, err := dom.NewDocumentFromReader(r)
-		if err != nil {
-			pw.CloseWithError(err)
-			return
-		}
-		// TODO: make this configurable?
-		style := styles.Get("github")
-		if style == nil {
-			style = styles.Fallback
-		}
-		formatter := html.New(html.Standalone())
-		doc.Find("pre>code").Each(func(i int, s *dom.Selection) {
-			lexer := detectLexer(s)
-			code := s.Contents().Text()
-			iterator, err := lexer.Tokenise(nil, code)
-			if err != nil {
-				pw.CloseWithError(err)
-				return
-			}
-			var html bytes.Buffer
-			err = formatter.Format(&html, style, iterator)
-			if err != nil {
-				pw.CloseWithError(err)
-				return
-			}
-
-			// Parent() because chroma html is already in a <pre><code>.
-			s.Parent().ReplaceWithHtml(html.String())
-		})
-
-		html, err := doc.Html()
-		if err != nil {
-			pw.CloseWithError(err)
-			return
-		}
-
-		pw.Write([]byte(html))
-		pw.Close()
-	}()
-	return pr
-}
-
-func detectLexer(s *dom.Selection) chroma.Lexer {
-	var lang string
-	classes, ok := s.Attr("class")
-	if ok {
-		for _, class := range strings.Split(classes, " ") {
-			if strings.HasPrefix(class, "language-") {
-				lang = strings.TrimPrefix(class, "language-")
-			}
-		}
-	}
-	var lexer chroma.Lexer
-	if lang != "" {
-		lexer = lexers.Get(lang)
-	}
-	if lexer == nil {
-		lexer = lexers.Analyse(s.Contents().Text())
-	}
-	if lexer == nil {
-		lexer = lexers.Fallback
-	}
-	return chroma.Coalesce(lexer)
-}
diff --git a/html_highlight.go b/html_highlight.go
@@ -0,0 +1,89 @@
+package static
+
+import (
+	"bytes"
+	"io"
+	"strings"
+
+	dom "github.com/PuerkitoBio/goquery"
+	"github.com/alecthomas/chroma"
+	"github.com/alecthomas/chroma/formatters/html"
+	"github.com/alecthomas/chroma/lexers"
+)
+
+// blankStyle is a blank style.
+var blankStyle = chroma.MustNewStyle("blank", chroma.StyleEntries{})
+
+// SyntaxHighlight returns a reader with HTML code prettified with chroma.
+func SyntaxHighlight(r io.Reader) io.ReadCloser {
+	pr, pw := io.Pipe()
+
+	go func() {
+		doc, err := dom.NewDocumentFromReader(r)
+		if err != nil {
+			pw.CloseWithError(err)
+			return
+		}
+
+		formatter := html.New(html.WithClasses())
+		doc.Find("pre > code").Each(func(i int, s *dom.Selection) {
+			lexer := detectLexer(s)
+			code := s.Contents().Text()
+
+			iterator, err := lexer.Tokenise(nil, code)
+			if err != nil {
+				pw.CloseWithError(err)
+				return
+			}
+
+			var buf bytes.Buffer
+			err = formatter.Format(&buf, blankStyle, iterator)
+			if err != nil {
+				pw.CloseWithError(err)
+				return
+			}
+
+			// Parent() because chroma html is already in a <pre><code>.
+			s.Parent().ReplaceWithHtml(buf.String())
+		})
+
+		html, err := doc.Html()
+		if err != nil {
+			pw.CloseWithError(err)
+			return
+		}
+
+		pw.Write([]byte(html))
+		pw.Close()
+	}()
+
+	return pr
+}
+
+// detectLexer returns a chroma lexer based on the classname.
+func detectLexer(s *dom.Selection) chroma.Lexer {
+	var lexer chroma.Lexer
+	var lang string
+
+	if classes, ok := s.Attr("class"); ok {
+		for _, c := range strings.Split(classes, " ") {
+			if strings.HasPrefix(c, "language-") {
+				lang = strings.TrimPrefix(c, "language-")
+			}
+		}
+	}
+
+	if lang != "" {
+		lexer = lexers.Get(lang)
+	}
+
+	if lexer == nil {
+		lexer = lexers.Analyse(s.Contents().Text())
+	}
+
+	if lexer == nil {
+		lexer = lexers.Fallback
+	}
+
+	return chroma.Coalesce(lexer)
+}
diff --git a/html_highlight_test.go b/html_highlight_test.go
@@ -0,0 +1,38 @@
+package static
+
+import (
+	"io/ioutil"
+	"strings"
+	"testing"
+)
+
+func TestSyntaxHighlight(t *testing.T) {
+	r := ioutil.NopCloser(strings.NewReader(`
+<pre><code>
+package main
+
+func main() {
+	fmt.Println("foo")
+}
+</code></pre>
+
+<pre><code class="language-yaml">
+foo: bar
+list:
+- 1
+- 2
+</code></pre>
+
+<pre><code>
+this is not even a lang
+</code></pre>
+	`))
+
+	r = SyntaxHighlight(r)
+	got, _ := ioutil.ReadAll(r)
+	expect, _ := ioutil.ReadFile("testdata/code.html")
+	if string(got) != string(expect) {
+		t.Errorf("expected %s but got %s", string(expect), string(got))
+		// ioutil.WriteFile("testdata/code.html", got, 0644)
+	}
+}
diff --git a/html_test.go b/html_test.go
@@ -5,7 +5,6 @@ import (
 	"io/ioutil"
 	"os"
 	"strings"
-	"testing"
 )
 
 func ExampleHeadingAnchors() {
@@ -53,34 +52,3 @@ func ExampleHeadingAnchors() {
 	// </a>Section 1</h2>
 	// 	</body></html>
 }
-
-func TestSyntaxHighlight(t *testing.T) {
-	r := ioutil.NopCloser(strings.NewReader(`
-<pre><code>
-package main
-
-func main() {
-	fmt.Println("foo")
-}
-</code></pre>
-
-<pre><code class="language-yaml">
-foo: bar
-list:
-- 1
-- 2
-</code></pre>
-
-<pre><code>
-this is not even a lang
-</code></pre>
-	`))
-
-	r = SyntaxHighlight(r)
-	got, _ := ioutil.ReadAll(r)
-	expect, _ := ioutil.ReadFile("testdata/code.html")
-	if string(got) != string(expect) {
-		t.Errorf("expected %s but got %s", string(expect), string(got))
-		// ioutil.WriteFile("testdata/code.html", got, 0644)
-	}
-}