Support $FORCE_COLOR

internal/colour/colour.go

@@ -18,23 +18,36 @@ const (
 //
 // If $NO_COLOR is set, text will be returned unmodified.
 func Title(text string) string {
-	if noColour() {
-		return text
-	}
-	return CodeTitle + text + CodeReset
+	return sprint(CodeTitle, text)
 }
 
 // Bold returns the given text in bold white.
 //
 // If $NO_COLOR is set, text will be returned unmodified.
 func Bold(text string) string {
-	if noColour() {
+	return sprint(CodeBold, text)
+}
+
+// sprint returns a string with a given colour and the reset code.
+//
+// It handles checking for NO_COLOR and FORCE_COLOR.
+func sprint(code, text string) string {
+	// TODO(@FollowTheProcess): I don't like checking *every* time but doing it
+	// via e.g. sync.Once means that tests are annoying unless we ensure env vars are
+	// set at the process level
+	noColor := os.Getenv("NO_COLOR") != ""
+	forceColor := os.Getenv("FORCE_COLOR") != ""
+
+	// $FORCE_COLOR overrides $NO_COLOR
+	if forceColor {
+		return code + text + CodeReset
+	}
+
+	// $NO_COLOR is next
+	if noColor {
 		return text
 	}
-	return CodeBold + text + CodeReset
-}
 
-// noColour returns whether the $NO_COLOR env var was set.
-func noColour() bool {
-	return os.Getenv("NO_COLOR") != ""
+	// Normal
+	return code + text + CodeReset
 }

internal/colour/colour_test.go

@@ -9,11 +9,12 @@ import (
 
 func TestColour(t *testing.T) {
 	tests := []struct {
-		name    string                   // Name of the test case
-		text    string                   // Text to colour
-		fn      func(text string) string // Printer function to return the coloured version of text
-		want    string                   // Expected result containing ANSI escape codes
-		noColor bool                     // Whether to set the $NO_COLOR env var
+		name       string                   // Name of the test case
+		text       string                   // Text to colour
+		fn         func(text string) string // Printer function to return the coloured version of text
+		want       string                   // Expected result containing ANSI escape codes
+		noColor    bool                     // Whether to set the $NO_COLOR env var
+		forceColor bool                     // Whether to set the $FORCE_COLOR env var
 	}{
 		{
 			name: "bold",
@@ -28,6 +29,21 @@ func TestColour(t *testing.T) {
 			noColor: true,
 			want:    "hello bold",
 		},
+		{
+			name:       "bold force color",
+			text:       "hello bold",
+			fn:         colour.Bold,
+			want:       colour.CodeBold + "hello bold" + colour.CodeReset,
+			forceColor: true,
+		},
+		{
+			name:       "bold force color and no color",
+			text:       "hello bold",
+			fn:         colour.Bold,
+			want:       colour.CodeBold + "hello bold" + colour.CodeReset,
+			forceColor: true, // force should override no
+			noColor:    true,
+		},
 		{
 			name: "title",
 			text: "Section",
@@ -41,13 +57,31 @@ func TestColour(t *testing.T) {
 			noColor: true,
 			want:    "Section",
 		},
+		{
+			name:       "title force color",
+			text:       "Section",
+			fn:         colour.Title,
+			want:       colour.CodeTitle + "Section" + colour.CodeReset,
+			forceColor: true,
+		},
+		{
+			name:       "title force color and no color",
+			text:       "Section",
+			fn:         colour.Title,
+			want:       colour.CodeTitle + "Section" + colour.CodeReset,
+			forceColor: true, // force should override no
+			noColor:    true,
+		},
 	}
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			if tt.noColor {
 				t.Setenv("NO_COLOR", "true")
 			}
+			if tt.forceColor {
+				t.Setenv("FORCE_COLOR", "true")
+			}
 			got := tt.fn(tt.text)
 			test.Equal(t, got, tt.want)
 		})