Improvements to display code

Now switchable, detects terminal. Don't be weird with tabs. Known issues are
not being themeable and bold match output stopping if colours are used inside.

display.go

@@ -0,0 +1,54 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/logrusorgru/aurora/v4"
+	"golang.org/x/sys/unix"
+)
+
+type Display struct {
+	a *aurora.Aurora
+}
+
+func NewDisplay(noColour bool) *Display {
+	if _, err := unix.IoctlGetTermios(1, unix.TCGETS); err != nil {
+		noColour = true
+	}
+	a := aurora.New(aurora.WithColors(!noColour))
+	return &Display{
+		a: a,
+	}
+}
+
+func (d *Display) Filename(name string) aurora.Value {
+	return d.a.BgBlue(d.a.White(name))
+}
+
+func (d *Display) LineNumber(lineNum int) aurora.Value {
+	return d.a.Green(lineNum)
+}
+
+func (d *Display) Match(text string) aurora.Value {
+	return d.a.Bold(text)
+}
+
+func (d *Display) TruncatedMarker() aurora.Value {
+	return d.a.Magenta("…")
+}
+
+func (d *Display) TruncatedBytes(byteCount int) aurora.Value {
+	return d.a.Faint(fmt.Sprintf("(%d bytes)", byteCount))
+}
+
+func (d *Display) BadUTF8Char() aurora.Value {
+	return d.a.Magenta("\uFFFD")
+}
+
+func (d *Display) CarriageReturn() aurora.Value {
+	return d.a.Magenta(`\r`)
+}
+
+func (d *Display) UnprintableChar() aurora.Value {
+	return d.a.Magenta(`·`)
+}

main.go

@@ -14,14 +14,12 @@ import (
 	"unicode"
 	"unicode/utf8"
 
-	"github.com/logrusorgru/aurora/v4"
 	"github.com/spf13/cobra"
 	"golang.org/x/sys/unix"
 )
 
 // TODO:
-//  - option to squelch aurora output
-//  - detect if terminal
+//  - bold of escaped output doesn't work
 //  - binary file detection
 //  - long-line / minified-file detection
 //  - ignore files by extension (or glob?)
@@ -65,6 +63,9 @@ var (
 	ignoreList   []string
 	ignoreMap    map[string]struct{}
 	ignoreCase   bool
+	noColour     bool
+	display      *Display
+	matchedAny   bool
 )
 
 func init() {
@@ -72,9 +73,12 @@ func init() {
 	rootCmd.Flags().StringSliceVarP(&searchFixed, "fixed", "Q", nil, "pattern to match (fixed string)")
 	rootCmd.Flags().StringSliceVarP(&ignoreList, "exclude", "x", []string{".git"}, "files/directories to exclude")
 	rootCmd.Flags().BoolVarP(&ignoreCase, "ignore-case", "i", false, "make all searches case insensitive")
+	rootCmd.Flags().BoolVarP(&noColour, "no-colour", "C", false, "disable colour output")
 }
 
 func run(c *cobra.Command, args []string) error {
+	display = NewDisplay(noColour)
+
 	if len(searchRegexp) == 0 && len(searchFixed) == 0 {
 		if len(args) == 0 {
 			return errors.New("no pattern specified")
@@ -196,11 +200,16 @@ func search(path string) error {
 
 		if !printedHeader {
 			printedHeader = true
-			fmt.Println(aurora.BgBlue(aurora.Bold(path)))
+			if !matchedAny {
+				matchedAny = true
+			} else {
+				fmt.Println("")
+			}
+			fmt.Println(display.Filename(path))
 		}
 
 		b.Reset()
-		fmt.Fprintf(&b, "%4d: ", aurora.Gray(16, lineNum))
+		fmt.Fprintf(&b, "%4d: ", display.LineNumber(lineNum))
 
 		if loc[0] < 128 {
 			escape(&b, line[0:loc[0]])
@@ -213,14 +222,15 @@ func search(path string) error {
 				start++
 			}
 
-			fmt.Fprintf(&b, "(%d bytes)%s", start, aurora.Magenta("…"))
+			b.WriteString(display.TruncatedBytes(start).String())
+			b.WriteString(display.TruncatedMarker().String())
 			escape(&b, line[start:loc[0]])
 		}
 
 		if loc[1]-loc[0] < 128 {
 			b2.Reset()
 			escape(&b2, line[loc[0]:loc[1]])
-			b.WriteString(aurora.Bold(b2.String()).String())
+			b.WriteString(display.Match(b2.String()).String())
 
 			if loc[1]+128 > len(line) {
 				escape(&b, line[loc[1]:])
@@ -233,7 +243,8 @@ func search(path string) error {
 					end--
 				}
 				escape(&b, line[loc[1]:end])
-				fmt.Fprintf(&b, "(%d bytes)%s", len(line)-end, aurora.Magenta("…"))
+				b.WriteString(display.TruncatedBytes(len(line) - end).String())
+				b.WriteString(display.TruncatedMarker().String())
 			}
 
 		} else {
@@ -247,8 +258,9 @@ func search(path string) error {
 
 			b2.Reset()
 			escape(&b2, line[loc[0]:end])
-			b.WriteString(aurora.Bold(b2.String()).String())
-			fmt.Fprintf(&b, "%s(%d bytes)", aurora.Magenta("…"), len(line)-end)
+			b.WriteString(display.Match(b2.String()).String())
+			b.WriteString(display.TruncatedMarker().String())
+			b.WriteString(display.TruncatedBytes(len(line) - end).String())
 
 		}
 
@@ -282,19 +294,17 @@ func escape(b *strings.Builder, s []byte) {
 
 		switch {
 		case r == utf8.RuneError && size == 1:
-			b.WriteString(aurora.Magenta("\uFFFD").String())
+			b.WriteString(display.BadUTF8Char().String())
 
 		case r == '\r':
-			b.WriteString(aurora.Magenta(`\r`).String())
+			b.WriteString(display.CarriageReturn().String())
 
-		case r == '\t':
-			b.WriteString(aurora.Magenta(`\t`).String())
-
-		case unicode.IsPrint(r):
+		case r == '\t',
+			unicode.IsPrint(r):
 			b.WriteRune(r)
 
 		default:
-			b.WriteString(aurora.Magenta(".").String())
+			b.WriteString(display.UnprintableChar().String())
 		}
 	}
 }