hswg: add .Attr, .AttrList, contains

Trying to figure out a sensible way of handle tags.

hswg/asciidoc.go

@@ -0,0 +1,54 @@
+package main
+
+import (
+	"bytes"
+	"io"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+)
+
+// isTitle returns the title level if the lines seem to form a title,
+// zero otherwise. Input lines may inclide trailing newlines.
+func isTitle(line1, line2 []byte) int {
+	// This is a very naïve method, we should target graphemes (thus at least
+	// NFC normalize the lines first) and account for wide characters.
+	diff := utf8.RuneCount(line1) - utf8.RuneCount(line2)
+	if len(line2) < 2 || diff < -1 || diff > 1 {
+		return 0
+	}
+
+	// "Don't be fooled by back-to-back delimited blocks."
+	// Still gets fooled by other things, though.
+	if bytes.IndexFunc(line1, func(r rune) bool {
+		return unicode.IsLetter(r) || unicode.IsNumber(r)
+	}) < 0 {
+		return 0
+	}
+
+	// The underline must be homogenous.
+	for _, r := range bytes.TrimRight(line2, "\r\n") {
+		if r != line2[0] {
+			return 0
+		}
+	}
+	return 1 + strings.IndexByte("=-~^+", line2[0])
+}
+
+func writeLine(w *io.PipeWriter, cur, next []byte) []byte {
+	if level := isTitle(cur, next); level > 0 {
+		w.Write(append(bytes.Repeat([]byte{'='}, level), ' '))
+		next = nil
+	}
+	w.Write(cur)
+	return next
+}
+
+// ConvertTitles converts AsciiDoc two-line (underlined) titles to single-line.
+func ConvertTitles(w *io.PipeWriter, input []byte) {
+	var last []byte
+	for _, cur := range bytes.SplitAfter(input, []byte{'\n'}) {
+		last = writeLine(w, last, cur)
+	}
+	writeLine(w, last, nil)
+}

hswg/main.go

@@ -19,8 +19,6 @@ import (
 	"strings"
 	"syscall"
 	"time"
-	"unicode"
-	"unicode/utf8"
 
 	"github.com/bytesparadise/libasciidoc/pkg/configuration"
 	"github.com/bytesparadise/libasciidoc/pkg/parser"
@@ -30,51 +28,6 @@ import (
 	"github.com/bytesparadise/libasciidoc/pkg/validator"
 )
 
-// isTitle returns the title level if the lines seem to form a title,
-// zero otherwise. Input lines may inclide trailing newlines.
-func isTitle(line1, line2 []byte) int {
-	// This is a very naïve method, we should target graphemes (thus at least
-	// NFC normalize the lines first) and account for wide characters.
-	diff := utf8.RuneCount(line1) - utf8.RuneCount(line2)
-	if len(line2) < 2 || diff < -1 || diff > 1 {
-		return 0
-	}
-
-	// "Don't be fooled by back-to-back delimited blocks."
-	// Still gets fooled by other things, though.
-	if bytes.IndexFunc(line1, func(r rune) bool {
-		return unicode.IsLetter(r) || unicode.IsNumber(r)
-	}) < 0 {
-		return 0
-	}
-
-	// The underline must be homogenous.
-	for _, r := range bytes.TrimRight(line2, "\r\n") {
-		if r != line2[0] {
-			return 0
-		}
-	}
-	return 1 + strings.IndexByte("=-~^+", line2[0])
-}
-
-func writeLine(w *io.PipeWriter, cur, next []byte) []byte {
-	if level := isTitle(cur, next); level > 0 {
-		w.Write(append(bytes.Repeat([]byte{'='}, level), ' '))
-		next = nil
-	}
-	w.Write(cur)
-	return next
-}
-
-// ConvertTitles converts AsciiDoc two-line (underlined) titles to single-line.
-func ConvertTitles(w *io.PipeWriter, input []byte) {
-	var last []byte
-	for _, cur := range bytes.SplitAfter(input, []byte{'\n'}) {
-		last = writeLine(w, last, cur)
-	}
-	writeLine(w, last, nil)
-}
-
 // Metadata contains select metadata about a rendered document.
 type Metadata struct {
 	types.Metadata
@@ -88,6 +41,21 @@ type Metadata struct {
 // be linked anywhere else.
 func (m *Metadata) IsDraft() bool { return m.Attributes.Has("draft") }
 
+// Attr is a shortcut for retrieving document attributes by name.
+func (m *Metadata) Attr(name string) string {
+	return m.Attributes.GetAsStringWithDefault(name, "")
+}
+
+// AttrList is similar to Attr, but splits the result at commas,
+// and trims whitespace around array elements.
+func (m *Metadata) AttrList(name string) []string {
+	res := strings.Split(m.Attr(name), ",")
+	for i := range res {
+		res[i] = strings.TrimSpace(res[i])
+	}
+	return res
+}
+
 // Render converts an io.Reader with an AsciiDoc document to HTML. So long as
 // the file could be read at all, it will always return a non-empty document.
 func Render(r io.Reader, config configuration.Configuration) (
@@ -446,6 +414,17 @@ func watchDirectory(dirname string) (<-chan *watchEvent, error) {
 	return ch, nil
 }
 
+var funcs = template.FuncMap{
+	"contains": func(needle string, haystack []string) bool {
+		for _, el := range haystack {
+			if el == needle {
+				return true
+			}
+		}
+		return false
+	},
+}
+
 func singleFile() {
 	html, meta, err := Render(os.Stdin, configuration.NewConfiguration())
 	if err != nil {
@@ -474,7 +453,7 @@ func main() {
 	if err != nil {
 		log.Fatalln(err)
 	}
-	tmplEntry, err := template.New("entry").Parse(string(header))
+	tmplEntry, err := template.New("entry").Funcs(funcs).Parse(string(header))
 	if err != nil {
 		log.Fatalln(err)
 	}
@@ -484,7 +463,7 @@ func main() {
 	if err != nil {
 		log.Fatalln(err)
 	}
-	tmplIndex, err := template.New("index").Parse(string(index))
+	tmplIndex, err := template.New("index").Funcs(funcs).Parse(string(index))
 	if err != nil {
 		log.Fatalln(err)
 	}