Color aliases for custom color support (#1101)

This moves the custom color support away from the raw ASCI escapes and
instead uses words for the standard 16 terminal colors or optionally
0-255 for the extended 256 color palette.

Also add missing envvar unset in the test

Co-authored-by: Benjamin Nørgaard <mail@blacksails.dev>

Author: blacksails

formatter/formatter.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"os"
 	"regexp"
+	"strconv"
 	"strings"
 )
 
@@ -50,13 +51,35 @@ func NewWithNoColorBool(noColor bool) Formatter {
 }
 
 func New(colorMode ColorMode) Formatter {
+	colorAliases := map[string]int{
+		"black":   0,
+		"red":     1,
+		"green":   2,
+		"yellow":  3,
+		"blue":    4,
+		"magenta": 5,
+		"cyan":    6,
+		"white":   7,
+	}
+	for colorAlias, n := range colorAliases {
+		colorAliases[fmt.Sprintf("bright-%s", colorAlias)] = n + 8
+	}
+
 	getColor := func(color, defaultEscapeCode string) string {
 		color = strings.ToUpper(strings.ReplaceAll(color, "-", "_"))
 		envVar := fmt.Sprintf("GINKGO_CLI_COLOR_%s", color)
-		if escapeCode := os.Getenv(envVar); escapeCode != "" {
-			return escapeCode
+		envVarColor := os.Getenv(envVar)
+		if envVarColor == "" {
+			return defaultEscapeCode
+		}
+		if colorCode, ok := colorAliases[envVarColor]; ok {
+			return fmt.Sprintf("\x1b[38;5;%dm", colorCode)
+		}
+		colorCode, err := strconv.Atoi(envVarColor)
+		if err != nil || colorCode < 0 || colorCode > 255 {
+			return defaultEscapeCode
 		}
-		return defaultEscapeCode
+		return fmt.Sprintf("\x1b[38;5;%dm", colorCode)
 	}
 
 	f := Formatter{

formatter/formatter_test.go

@@ -62,19 +62,46 @@ var _ = Describe("Formatter", func() {
 		})
 	})
 
-	Context("with environment overrides", func() {
-		BeforeEach(func() {
-			os.Setenv("GINKGO_CLI_COLOR_RED", "\x1b[31m")
-		})
+	DescribeTable("with environment overrides",
+		func(envVars map[string]string, input, expected string) {
+			for envVar, value := range envVars {
+				os.Setenv(envVar, value)
+			}
+			f := formatter.New(colorMode)
+			Ω(f.F(input)).Should(Equal(expected))
+			for envVar := range envVars {
+				os.Unsetenv(envVar)
+			}
+		},
 
-		AfterEach(func() {
-			os.Unsetenv("GINKGO_CLI_COLOR_RED")
-		})
+		Entry("uses default for too low codes", map[string]string{
+			"GINKGO_CLI_COLOR_RED": "-1",
+		}, "{{red}}hi there{{/}}", "\x1b[38;5;9mhi there\x1b[0m"),
 
-		It("uses the escape codes from the environment variables", func() {
-			Ω(f.F("{{red}}hi there{{/}}")).Should(Equal("\x1b[31mhi there\x1b[0m"))
-		})
-	})
+		Entry("uses default for too high codes", map[string]string{
+			"GINKGO_CLI_COLOR_RED": "256",
+		}, "{{red}}hi there{{/}}", "\x1b[38;5;9mhi there\x1b[0m"),
+
+		Entry("supports literal alias for 8bit color", map[string]string{
+			"GINKGO_CLI_COLOR_RED": "red",
+		}, "{{red}}hi there{{/}}", "\x1b[38;5;1mhi there\x1b[0m"),
+
+		Entry("supports number alias for 8bit color", map[string]string{
+			"GINKGO_CLI_COLOR_RED": "1",
+		}, "{{red}}hi there{{/}}", "\x1b[38;5;1mhi there\x1b[0m"),
+
+		Entry("supports 16bit colors (bright)", map[string]string{
+			"GINKGO_CLI_COLOR_RED": "9",
+		}, "{{red}}hi there{{/}}", "\x1b[38;5;9mhi there\x1b[0m"),
+
+		Entry("supports 16bit color literal aliases (bright)", map[string]string{
+			"GINKGO_CLI_COLOR_RED": "bright-red",
+		}, "{{red}}hi there{{/}}", "\x1b[38;5;9mhi there\x1b[0m"),
+
+		Entry("supports extended 256 colors", map[string]string{
+			"GINKGO_CLI_COLOR_RED": "16",
+		}, "{{red}}hi there{{/}}", "\x1b[38;5;16mhi there\x1b[0m"),
+	)
 
 	Describe("NewWithNoColorBool", func() {
 		Context("when the noColor bool is true", func() {