chore(helpers): Enhance the Default and DefaultFunc functionality…

… and add `DefaultFunc`

Signed-off-by: Flc゛ <[email protected]>

helpers/values.go

@@ -117,28 +117,54 @@ func When[T any](condition bool, callbacks func() T, defaults ...T) T {
 	return zero
 }
 
-// Default returns defaultValue if value is zero, otherwise value.
+// Default returns the first non-zero value.
+// If all values are zero, return the zero value.
 //
 //	Default("", "foo") // "foo"
 //	Default("bar", "foo") // "bar"
-func Default[T comparable](value T, defaultValue T) T {
+//	Default("", "", "foo") // "foo"
+func Default[T comparable](values ...T) T {
 	var zero T
-	if value == zero {
-		return defaultValue
+	for _, value := range values {
+		if value != zero {
+			return value
+		}
 	}
-	return value
+	return zero
+}
+
+func DefaultFunc[T comparable](callbacks ...func() T) T {
+	var zero, value T
+	for _, callback := range callbacks {
+		if callback != nil {
+			value = callback()
+			if value != zero {
+				return value
+			}
+		}
+	}
+	return zero
 }
 
 // DefaultWithFunc returns defaultValue if value is zero, otherwise value.
 //
 //	DefaultWithFunc("", func() string { return "foo" }) // "foo"
 //	DefaultWithFunc("bar", func() string { return "foo" }) // "bar"
-func DefaultWithFunc[T comparable](value T, defaultValue func() T) T {
+//	DefaultWithFunc("", func() string { return "" }, func() string { return "foo" }) // "foo"
+func DefaultWithFunc[T comparable](value T, callbacks ...func() T) T {
 	var zero T
-	if value == zero {
-		return defaultValue()
+	if value != zero {
+		return value
 	}
-	return value
+	for _, callback := range callbacks {
+		if callback != nil {
+			value = callback()
+			if value != zero {
+				return value
+			}
+		}
+	}
+	return zero
 }
 
 // Ptr returns a pointer to the value.

helpers/values_test.go

@@ -243,9 +243,60 @@ func TestDefault(t *testing.T) {
 	// ptr
 	got4 := Default(nil, &foo{Name: "bar"})
 	assert.Equal(t, "bar", got4.Name)
+
+	// more values
+	got5 := Default(0, 10, 20, 30)
+	assert.Equal(t, 10, got5)
+
+	got6 := Default(0, 0, 20)
+	assert.Equal(t, 20, got6)
 }
 
-func TestDefaultWith(t *testing.T) {
+func TestDefaultFunc(t *testing.T) {
+	// string
+	got := DefaultFunc(func() string {
+		return ""
+	}, func() string {
+		return "foo"
+	})
+	assert.Equal(t, "foo", got)
+
+	// int
+	got2 := DefaultFunc(func() int {
+		return 0
+	}, func() int {
+		return 10
+	})
+	assert.Equal(t, 10, got2)
+
+	// struct
+	got3 := DefaultFunc(func() foo {
+		return foo{}
+	}, func() foo {
+		return foo{Name: "bar"}
+	})
+	assert.Equal(t, "bar", got3.Name)
+
+	// ptr
+	got4 := DefaultFunc(func() *foo {
+		return nil
+	}, func() *foo {
+		return &foo{Name: "bar"}
+	})
+	assert.Equal(t, "bar", got4.Name)
+
+	// more values
+	got5 := DefaultFunc(func() int {
+		return 0
+	}, func() int {
+		return 0
+	}, func() int {
+		return 10
+	})
+	assert.Equal(t, 10, got5)
+}
+
+func TestDefaultWithFunc(t *testing.T) {
 	// string
 	got := DefaultWithFunc("", func() string {
 		return "foo"
@@ -269,6 +320,14 @@ func TestDefaultWith(t *testing.T) {
 		return &foo{Name: "bar"}
 	})
 	assert.Equal(t, "bar", got4.Name)
+
+	// more values
+	got5 := DefaultWithFunc(0, func() int {
+		return 0
+	}, func() int {
+		return 10
+	})
+	assert.Equal(t, 10, got5)
 }
 
 func TestPtrAndVal(t *testing.T) {