Add a soft wrap option to handle Lines and ShowLineNumbers behavior

config.go

@@ -31,6 +31,7 @@ type Config struct {
 	Language    string `json:"language,omitempty" help:"Language of code file." short:"l" group:"Settings" placeholder:"go"`
 	Theme       string `json:"theme" help:"Theme to use for syntax highlighting." short:"t" group:"Settings" placeholder:"charm"`
 	Wrap        int    `json:"wrap" help:"Wrap lines at a specific width." short:"w" group:"Settings" default:"0" placeholder:"80"`
+	SoftWrap    bool   `json:"soft-wrap" help:"Do not count wrapped lines (Lines & LineHeight)." group:"Settings"`
 
 	Output         string        `json:"output,omitempty" help:"Output location for {{.svg}}, {{.png}}, or {{.webp}}." short:"o" group:"Settings" default:"" placeholder:"freeze.svg"`
 	Execute        string        `json:"-" help:"Capture output of command execution." short:"x" group:"Settings" default:""`

main.go

@@ -177,7 +177,7 @@ func main() {
 	strippedInput = cut(strippedInput, config.Lines)
 
 	// wrap to character limit.
-	if config.Wrap > 0 {
+	if config.Wrap > 0 && !config.SoftWrap {
 		strippedInput = wordwrap.String(strippedInput, config.Wrap)
 		input = wordwrap.String(input, config.Wrap)
 	}
@@ -195,6 +195,23 @@ func main() {
 		}
 	}
 
+	isRealLine := []bool{}
+	strippedIsRealLine := []bool{}
+	// wrap to character limit.
+	if config.Wrap > 0 && config.SoftWrap {
+		isRealLine = SoftWrap(input, config.Wrap)
+		strippedIsRealLine = SoftWrap(strippedInput, config.Wrap)
+		strippedInput = wordwrap.String(strippedInput, config.Wrap)
+		input = wordwrap.String(input, config.Wrap)
+	}
+
+	if config.Wrap <= 0 {
+		// If Wrap is disabled, but SoftWrap enabled, we force disable SoftWrap as it does not make sense
+		// to keep this option enabled.
+		printError("Wrap option disabled, but SoftWrap option enabled", fmt.Errorf("wrap option disabled"))
+		config.SoftWrap = false
+	}
+
 	s, ok := styles.Registry[strings.ToLower(config.Theme)]
 	if s == nil || !ok {
 		s = charmStyle
@@ -320,6 +337,7 @@ func main() {
 
 	config.LineHeight *= float64(scale)
 
+	softWrapOffset := 0
 	for i, line := range text {
 		if isAnsi {
 			line.SetText("")
@@ -330,9 +348,20 @@ func main() {
 			ln := etree.NewElement("tspan")
 			ln.CreateAttr("xml:space", "preserve")
 			ln.CreateAttr("fill", s.Get(chroma.LineNumbers).Colour.String())
-			ln.SetText(fmt.Sprintf("%3d  ", i+1+offsetLine))
+			if config.SoftWrap {
+				if (isAnsi && strippedIsRealLine[i]) || (!isAnsi && isRealLine[i]) {
+					ln.SetText(fmt.Sprintf("%3d  ", i+1+offsetLine-softWrapOffset))
+				} else {
+					ln.SetText("     ")
+				}
+			} else {
+				ln.SetText(fmt.Sprintf("%3d  ", i+1+offsetLine))
+			}
 			line.InsertChildAt(0, ln)
 		}
+		if config.SoftWrap && !((isAnsi && strippedIsRealLine[i]) || (!isAnsi && isRealLine[i])) {
+			softWrapOffset++
+		}
 		x := float64(config.Padding[left] + config.Margin[left])
 		y := (float64(i+1))*(config.Font.Size*config.LineHeight) + float64(config.Padding[top]) + float64(config.Margin[top])
 

soft_wrap.go

@@ -0,0 +1,24 @@
+package main
+
+import (
+	"github.com/muesli/reflow/wordwrap"
+	"strings"
+)
+
+func SoftWrap(input string, wrapLength int) []bool {
+	var wrap []bool
+	for _, line := range strings.Split(input, "\n") {
+		wrappedLine := wordwrap.String(line, wrapLength)
+
+		for i := range strings.Split(wrappedLine, "\n") {
+			if i == 0 {
+				// We want line number on the original line
+				wrap = append(wrap, true)
+			} else {
+				// for wrapped line, we do not want line number
+				wrap = append(wrap, false)
+			}
+		}
+	}
+	return wrap
+}

soft_wrap_test.go

@@ -0,0 +1,62 @@
+package main
+
+import (
+	"reflect"
+	"testing"
+)
+
+// Mock the dependency if needed, assuming wordwrap.String works correctly.
+func TestSoftWrap(t *testing.T) {
+	tests := []struct {
+		name       string
+		input      string
+		wrapLength int
+		expected   []bool
+	}{
+		{
+			name:       "Single short line, no wrapping",
+			input:      "Hello",
+			wrapLength: 10,
+			expected:   []bool{true},
+		},
+		{
+			name:       "Single long line, wrapping",
+			input:      "Hello World, this is a long line",
+			wrapLength: 10,
+			expected:   []bool{true, false, false, false},
+		},
+		{
+			name:       "Multiple lines, some wrapped",
+			input:      "Short\nThis is a long line",
+			wrapLength: 10,
+			expected:   []bool{true, true, false},
+		},
+		{
+			name:       "Multiple lines, multiple wraps",
+			input:      "This is an long line\nThis is an other long line\nThis is the last long line\nShort line",
+			wrapLength: 10,
+			expected:   []bool{true, false, true, false, false, true, false, false, true},
+		},
+		{
+			name:       "Empty input",
+			input:      "",
+			wrapLength: 10,
+			expected:   []bool{true},
+		},
+		{
+			name:       "Lines with spaces only",
+			input:      "    \n      ",
+			wrapLength: 5,
+			expected:   []bool{true, true},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := SoftWrap(tt.input, tt.wrapLength)
+			if !reflect.DeepEqual(got, tt.expected) {
+				t.Errorf("SoftWrap() = %v, expected %v", got, tt.expected)
+			}
+		})
+	}
+}