feat: NO_COLOR env to not use ansi colors in miro

internal/output/output.go

@@ -21,9 +21,6 @@ var (
 		pass:        0x7bf1a8,
 		fail:        0xff8fa3,
 	}
-
-	chevron = NewStyle().FG(palette.chevronTeal).Bold().Italic().Apply("›")
-	prefix  = NewStyle().FG(palette.miroGreen).Bold().Italic().Apply("miro") + " " + chevron + " "
 )
 
 func label(text string, color uint32) string {
@@ -42,10 +39,19 @@ func LabelInfo(text string) string {
 	return label(text, palette.info)
 }
 
+func noColor() bool {
+	return os.Getenv("NO_COLOR") != ""
+}
+
+func prefix() string {
+	chevron := NewStyle().FG(palette.chevronTeal).Bold().Italic().Apply("›")
+	return NewStyle().FG(palette.miroGreen).Bold().Italic().Apply("miro") + " " + chevron + " "
+}
+
 func Format(msg string) string {
 	body := strings.TrimRight(msg, "\n")
 	suffix := msg[len(body):]
-	return prefix + body + suffix
+	return prefix() + body + suffix
 }
 
 func Println(msg string) {

internal/output/output_test.go

@@ -0,0 +1,58 @@
+package output
+
+import (
+	"os"
+	"strings"
+	"testing"
+)
+
+func TestFormatIncludesANSIByDefault(t *testing.T) {
+	t.Setenv("NO_COLOR", "")
+
+	got := Format("hello\n")
+	if !strings.Contains(got, "\x1b[") {
+		t.Fatalf("Format() = %q, want ANSI styling", got)
+	}
+	if !strings.Contains(got, "hello\n") {
+		t.Fatalf("Format() = %q, want message body", got)
+	}
+}
+
+func TestFormatPlainWhenNoColorSet(t *testing.T) {
+	t.Setenv("NO_COLOR", "1")
+
+	if got := Format("hello\n"); got != "miro › hello\n" {
+		t.Fatalf("Format() = %q, want %q", got, "miro › hello\n")
+	}
+}
+
+func TestLabelsPlainWhenNoColorSet(t *testing.T) {
+	t.Setenv("NO_COLOR", "1")
+
+	if got := LabelInfo("RUN"); got != "RUN" {
+		t.Fatalf("LabelInfo() = %q, want %q", got, "RUN")
+	}
+	if got := LabelPass("PASS"); got != "PASS" {
+		t.Fatalf("LabelPass() = %q, want %q", got, "PASS")
+	}
+	if got := LabelFail("FAIL"); got != "FAIL" {
+		t.Fatalf("LabelFail() = %q, want %q", got, "FAIL")
+	}
+}
+
+func TestFormatReadsNoColorAtRuntime(t *testing.T) {
+	t.Setenv("NO_COLOR", "")
+
+	styled := Format("hello\n")
+	if err := os.Setenv("NO_COLOR", "1"); err != nil {
+		t.Fatalf("Setenv() error = %v", err)
+	}
+
+	plain := Format("hello\n")
+	if !strings.Contains(styled, "\x1b[") {
+		t.Fatalf("styled Format() = %q, want ANSI styling", styled)
+	}
+	if plain != "miro › hello\n" {
+		t.Fatalf("plain Format() = %q, want %q", plain, "miro › hello\n")
+	}
+}

internal/output/termstyle.go

@@ -40,7 +40,7 @@ func (s Style) BG(rgb uint32) Style {
 }
 
 func (s Style) Apply(text string) string {
-	if !s.bold && !s.italic && s.fg == nil && s.bg == nil {
+	if noColor() || (!s.bold && !s.italic && s.fg == nil && s.bg == nil) {
 		return text
 	}