From 9d46ee1cdedfacd4a8819236516ff5da977c2354 Mon Sep 17 00:00:00 2001
From: gak <gak@gak0.com>
Date: Fri, 17 May 2024 10:03:55 +1000
Subject: [PATCH] feat: LOG_COLOR env to override tty detection (#1508)

LOG_COLOR env to override tty detection

eg `LOG_COLOR=1 LOG_LEVEL=trace go test -v ./buildengine -run TestEngine`
---
 internal/log/api.go       | 4 +++-
 internal/log/configure.go | 3 ++-
 internal/log/plain.go     | 6 ++++--
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/internal/log/api.go b/internal/log/api.go
index d721f47fdd..bb6bfba2e9 100644
--- a/internal/log/api.go
+++ b/internal/log/api.go
@@ -66,5 +66,7 @@ func ContextWithLogger(ctx context.Context, logger *Logger) context.Context {
 }
 
 func ContextWithNewDefaultLogger(ctx context.Context) context.Context {
-	return ContextWithLogger(ctx, Configure(os.Stderr, Config{Level: Debug}))
+	// Matches LOG_COLOR in log.Config. This is a special case for the default logger in testing.
+	color := os.Getenv("LOG_COLOR") != ""
+	return ContextWithLogger(ctx, Configure(os.Stderr, Config{Level: Debug, Color: color}))
 }
diff --git a/internal/log/configure.go b/internal/log/configure.go
index c6534e6342..94e6c7950a 100644
--- a/internal/log/configure.go
+++ b/internal/log/configure.go
@@ -9,6 +9,7 @@ type Config struct {
 	Level      Level `help:"Log level." default:"info" env:"LOG_LEVEL"`
 	JSON       bool  `help:"Log in JSON format." env:"LOG_JSON"`
 	Timestamps bool  `help:"Include timestamps in text logs." env:"LOG_TIMESTAMPS"`
+	Color      bool  `help:"Enable colored output regardless of TTY." env:"LOG_COLOR"`
 }
 
 // Configure returns a new logger based on the config.
@@ -17,7 +18,7 @@ func Configure(w io.Writer, cfg Config) *Logger {
 	if cfg.JSON {
 		sink = newJSONSink(w)
 	} else {
-		sink = newPlainSink(w, cfg.Timestamps)
+		sink = newPlainSink(w, cfg.Timestamps, cfg.Color)
 	}
 	return New(cfg.Level, sink)
 }
diff --git a/internal/log/plain.go b/internal/log/plain.go
index 02881ec353..0bbabda99e 100644
--- a/internal/log/plain.go
+++ b/internal/log/plain.go
@@ -19,9 +19,11 @@ var colours = map[Level]string{
 
 var _ Sink = (*plainSink)(nil)
 
-func newPlainSink(w io.Writer, logTime bool) *plainSink {
+func newPlainSink(w io.Writer, logTime bool, alwaysColor bool) *plainSink {
 	var isaTTY bool
-	if f, ok := w.(*os.File); ok {
+	if alwaysColor {
+		isaTTY = true
+	} else if f, ok := w.(*os.File); ok {
 		isaTTY = isatty.IsTerminal(f.Fd())
 	}
 	return &plainSink{