Test: Add tests for color.go

color/color.go

@@ -45,17 +45,7 @@ func Green(style int, format string, a ...interface{}) string {
 	return colorString(FgGreen, style, format, a...)
 }
 
-// Yellow returns a string with yellow foreground
-func Yellow(style int, format string, a ...interface{}) string {
-	return colorString(FgYellow, style, format, a...)
-}
-
 // Blue returns a string with blue foreground
 func Blue(style int, format string, a ...interface{}) string {
 	return colorString(FgBlue, style, format, a...)
 }
-
-// Purple returns a string with purple foreground
-func Purple(style int, format string, a ...interface{}) string {
-	return colorString(FgPurple, style, format, a...)
-}

color/color_test.go

@@ -0,0 +1,54 @@
+package color
+
+import (
+	"os"
+	"testing"
+)
+
+// Setup tests
+var tests = []struct {
+	color    func(style int, format string, a ...interface{}) string
+	input    []string
+	expected string
+}{
+	{Black, []string{"%s", "foobar"}, "\033[30;1mfoobar"},
+	{Red, []string{"%s %s", "foobar", "hey"}, "\033[31;1mfoobar hey"},
+	{Green, []string{"%s", ""}, "\033[32;1m"},
+	{Blue, []string{"foobar"}, "\033[34;1mfoobar"},
+}
+
+func TestColors(t *testing.T) {
+	// Redirect stdout
+	oldStdout := os.Stdout
+	_, w, err := os.Pipe()
+	if err != nil {
+		t.Fatalf("ColorString failed to redirect stdout because %s", err.Error())
+	}
+	os.Stdout = w
+
+	// Restore old stdout
+	defer func() {
+		w.Close()
+		os.Stdout = oldStdout
+	}()
+
+	// Check output
+	var out string
+	for _, test := range tests {
+		if len(test.input) == 1 {
+			// With formatter
+			out = test.color(Regular, test.input[0])
+		} else {
+			// Without formatter
+			s := make([]interface{}, len(test.input)-1)
+			for i, v := range test.input[1:] {
+				s[i] = v
+			}
+			out = test.color(Regular, test.input[0], s...)
+		}
+
+		if test.expected != out {
+			t.Errorf("Color failed: got %s, want %s", out, test.expected)
+		}
+	}
+}