support monochrome mode

Signed-off-by: Tw <[email protected]>
elves · Aug 7, 2023 · 77ec605 · 77ec605
1 parent a1bfc0e
commit 77ec605
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Showing 2 changed files with 22 additions and 7 deletions.
diff --git a/pkg/shell/shell.go b/pkg/shell/shell.go
@@ -19,6 +19,7 @@ import (
 	"src.elv.sh/pkg/parse"
 	"src.elv.sh/pkg/prog"
 	"src.elv.sh/pkg/sys"
+	"src.elv.sh/pkg/ui"
 )
 
 var logger = logutil.GetLogger("[shell] ")
@@ -61,6 +62,7 @@ func (p *Program) Run(fds [3]*os.File, args []string) error {
 	cleanup2 := initSignal(fds)
 	defer cleanup2()
 
+	ui.NoColor = os.Getenv("NO_COLOR") != ""
 	interactive := len(args) == 0
 	ev := p.makeEvaler(fds[2], interactive)
 	defer ev.PreExit()

diff --git a/pkg/ui/styling.go b/pkg/ui/styling.go
@@ -39,7 +39,8 @@ func Stylings(ts ...Styling) Styling { return jointStyling(ts) }
 
 // Common stylings.
 var (
-	Reset Styling = reset{}
+	NoColor bool    = false
+	Reset   Styling = reset{}
 
 	FgDefault Styling = setForeground{nil}
 
@@ -116,12 +117,24 @@ type boolOn struct{ f boolField }
 type boolOff struct{ f boolField }
 type boolToggle struct{ f boolField }
 
-func (reset) transform(s *Style)           { *s = Style{} }
-func (t setForeground) transform(s *Style) { s.Fg = t.c }
-func (t setBackground) transform(s *Style) { s.Bg = t.c }
-func (t boolOn) transform(s *Style)        { *t.f.get(s) = true }
-func (t boolOff) transform(s *Style)       { *t.f.get(s) = false }
-func (t boolToggle) transform(s *Style)    { p := t.f.get(s); *p = !*p }
+func (reset) transform(s *Style) { *s = Style{} }
+func (t setForeground) transform(s *Style) {
+	if NoColor {
+		s.Fg = nil
+	} else {
+		s.Fg = t.c
+	}
+}
+func (t setBackground) transform(s *Style) {
+	if NoColor {
+		s.Bg = nil
+	} else {
+		s.Bg = t.c
+	}
+}
+func (t boolOn) transform(s *Style)     { *t.f.get(s) = true }
+func (t boolOff) transform(s *Style)    { *t.f.get(s) = false }
+func (t boolToggle) transform(s *Style) { p := t.f.get(s); *p = !*p }
 
 type boolField interface{ get(*Style) *bool }