Clear background colour for TTY formatters.

.golangci.yml

@@ -17,6 +17,7 @@ linters:
     - gochecknoglobals
     - funlen
     - godox
+    - wsl
 
 linters-settings:
   govet:

.travis.yml

@@ -2,7 +2,7 @@ sudo: false
 language: go
 script:
   - go test -v ./...
-  - curl -sfL https://install.goreleaser.com/github.com/golangci/golangci-lint.sh | bash -s v1.19.1
+  - curl -sfL https://install.goreleaser.com/github.com/golangci/golangci-lint.sh | bash -s v1.20.0
   - ./bin/golangci-lint run
   - git clean -fdx .
 after_success:

cmd/chroma/main.go

@@ -41,7 +41,7 @@ command, for Go.
 		List       bool             `help:"List lexers, styles and formatters."`
 		Unbuffered bool             `help:"Do not buffer output."`
 		Trace      bool             `help:"Trace lexer states as they are traversed."`
-		Check      bool             `help:"Do not format, check for tokenization errors instead."`
+		Check      bool             `help:"Do not format, check for tokenisation errors instead."`
 		Filename   string           `help:"Filename to use for selecting a lexer when reading from stdin."`
 
 		Lexer     string `help:"Lexer to use when formatting." default:"autodetect" short:"l" enum:"${lexers}"`
@@ -117,15 +117,12 @@ func main() {
 	}
 	defer w.Flush() // nolint: errcheck
 
-	if cli.JSON {
+	switch {
+	case cli.JSON:
 		cli.Formatter = "json"
-	}
-
-	if cli.HTML {
+	case cli.HTML:
 		cli.Formatter = "html"
-	}
-
-	if cli.SVG {
+	case cli.SVG:
 		cli.Formatter = "svg"
 	}
 
@@ -149,47 +146,7 @@ func main() {
 	}
 
 	if cli.Formatter == "html" {
-		options := []html.Option{
-			html.TabWidth(cli.HTMLTabWidth),
-			html.BaseLineNumber(cli.HTMLBaseLine),
-		}
-		if cli.HTMLPrefix != "" {
-			options = append(options, html.ClassPrefix(cli.HTMLPrefix))
-		}
-		if !cli.HTMLInlineStyles {
-			options = append(options, html.WithClasses())
-		}
-		if !cli.HTMLOnly {
-			options = append(options, html.Standalone())
-		}
-		if cli.HTMLLines {
-			options = append(options, html.WithLineNumbers())
-		}
-		if cli.HTMLLinesTable {
-			options = append(options, html.LineNumbersInTable())
-		}
-		if cli.HTMLPreventSurroundingPre {
-			options = append(options, html.PreventSurroundingPre())
-		}
-		if len(cli.HTMLHighlight) > 0 {
-			ranges := [][2]int{}
-			for _, span := range strings.Split(cli.HTMLHighlight, ",") {
-				parts := strings.Split(span, ":")
-				if len(parts) > 2 {
-					ctx.Fatalf("range should be N[:M], not %q", span)
-				}
-				start, err := strconv.ParseInt(parts[0], 10, 64)
-				ctx.FatalIfErrorf(err, "min value of range should be integer not %q", parts[0])
-				end := start
-				if len(parts) == 2 {
-					end, err = strconv.ParseInt(parts[1], 10, 64)
-					ctx.FatalIfErrorf(err, "max value of range should be integer not %q", parts[1])
-				}
-				ranges = append(ranges, [2]int{int(start), int(end)})
-			}
-			options = append(options, html.HighlightLines(ranges))
-		}
-		formatters.Register("html", html.New(options...))
+		configureHTMLFormatter(ctx)
 	}
 	if len(cli.Files) == 0 {
 		contents, err := ioutil.ReadAll(os.Stdin)
@@ -208,6 +165,50 @@ func main() {
 	}
 }
 
+func configureHTMLFormatter(ctx *kong.Context) {
+	options := []html.Option{
+		html.TabWidth(cli.HTMLTabWidth),
+		html.BaseLineNumber(cli.HTMLBaseLine),
+	}
+	if cli.HTMLPrefix != "" {
+		options = append(options, html.ClassPrefix(cli.HTMLPrefix))
+	}
+	if !cli.HTMLInlineStyles {
+		options = append(options, html.WithClasses())
+	}
+	if !cli.HTMLOnly {
+		options = append(options, html.Standalone())
+	}
+	if cli.HTMLLines {
+		options = append(options, html.WithLineNumbers())
+	}
+	if cli.HTMLLinesTable {
+		options = append(options, html.LineNumbersInTable())
+	}
+	if cli.HTMLPreventSurroundingPre {
+		options = append(options, html.PreventSurroundingPre())
+	}
+	if len(cli.HTMLHighlight) > 0 {
+		ranges := [][2]int{}
+		for _, span := range strings.Split(cli.HTMLHighlight, ",") {
+			parts := strings.Split(span, ":")
+			if len(parts) > 2 {
+				ctx.Fatalf("range should be N[:M], not %q", span)
+			}
+			start, err := strconv.ParseInt(parts[0], 10, 64)
+			ctx.FatalIfErrorf(err, "min value of range should be integer not %q", parts[0])
+			end := start
+			if len(parts) == 2 {
+				end, err = strconv.ParseInt(parts[1], 10, 64)
+				ctx.FatalIfErrorf(err, "max value of range should be integer not %q", parts[1])
+			}
+			ranges = append(ranges, [2]int{int(start), int(end)})
+		}
+		options = append(options, html.HighlightLines(ranges))
+	}
+	formatters.Register("html", html.New(options...))
+}
+
 func listAll() {
 	fmt.Println("lexers:")
 	sort.Sort(lexers.Registry.Lexers)

delegate.go

@@ -34,7 +34,7 @@ type insertion struct {
 	tokens     []Token
 }
 
-func (d *delegatingLexer) Tokenise(options *TokeniseOptions, text string) (Iterator, error) {
+func (d *delegatingLexer) Tokenise(options *TokeniseOptions, text string) (Iterator, error) { // nolint: gocognit
 	tokens, err := Tokenise(Coalesce(d.language), options, text)
 	if err != nil {
 		return nil, err

formatters/tty_indexed.go

@@ -200,6 +200,7 @@ func findClosest(table *ttyTable, seeking chroma.Colour) chroma.Colour {
 }
 
 func styleToEscapeSequence(table *ttyTable, style *chroma.Style) map[chroma.TokenType]string {
+	style = clearBackground(style)
 	out := map[chroma.TokenType]string{}
 	for _, ttype := range style.Types() {
 		entry := style.Get(ttype)
@@ -208,6 +209,17 @@ func styleToEscapeSequence(table *ttyTable, style *chroma.Style) map[chroma.Toke
 	return out
 }
 
+// Clear the background colour.
+func clearBackground(style *chroma.Style) *chroma.Style {
+	builder := style.Builder()
+	bg := builder.Get(chroma.Background)
+	bg.Background = 0
+	bg.NoInherit = true
+	builder.AddEntry(chroma.Background, bg)
+	style, _ = builder.Build()
+	return style
+}
+
 type indexedTTYFormatter struct {
 	table *ttyTable
 }

formatters/tty_truecolour.go

@@ -11,6 +11,7 @@ import (
 var TTY16m = Register("terminal16m", chroma.FormatterFunc(trueColourFormatter))
 
 func trueColourFormatter(w io.Writer, style *chroma.Style, it chroma.Iterator) error {
+	style = clearBackground(style)
 	for token := it(); token != chroma.EOF; token = it() {
 		entry := style.Get(token.Type)
 		if !entry.IsZero() {

go.mod

@@ -20,3 +20,5 @@ require (
 )
 
 replace github.com/GeertJohan/go.rice => github.com/alecthomas/go.rice v1.0.1-0.20190719113735-961b99d742e7
+
+go 1.13

lexers/h/http.go

@@ -65,7 +65,7 @@ func httpBodyContentTypeLexer(lexer Lexer) Lexer { return &httpBodyContentTyper{
 
 type httpBodyContentTyper struct{ Lexer }
 
-func (d *httpBodyContentTyper) Tokenise(options *TokeniseOptions, text string) (Iterator, error) {
+func (d *httpBodyContentTyper) Tokenise(options *TokeniseOptions, text string) (Iterator, error) { // nolint: gocognit
 	var contentType string
 	var isContentType bool
 	var subIterator Iterator

regexp.go

@@ -255,7 +255,7 @@ func (l *LexerState) Get(key interface{}) interface{} {
 }
 
 // Iterator returns the next Token from the lexer.
-func (l *LexerState) Iterator() Token {
+func (l *LexerState) Iterator() Token { // nolint: gocognit
 	for l.Pos < len(l.Text) && len(l.Stack) > 0 {
 		// Exhaust the iterator stack, if any.
 		for len(l.iteratorStack) > 0 {