feat: add isTrue util function.

Author: ghosind

util.go

@@ -57,3 +57,19 @@ func isPanic(fn func()) (err any) {
 
 	return
 }
+
+// isTrue checks whether a value is truthy or not. It'll return true if the value is not the zero
+// value for its type. For a slice, a truthy value should not be the zero value and the length must
+// be greater than 0. For nil, it'll always return false.
+func isTrue(v any) bool {
+	rv := reflect.ValueOf(v)
+
+	switch rv.Kind() {
+	case reflect.Invalid:
+		return false // always false
+	case reflect.Slice:
+		return v != nil && rv.Len() > 0
+	default:
+		return !rv.IsZero()
+	}
+}

util_test.go

@@ -41,3 +41,23 @@ func TestIsPanic(t *testing.T) {
 		panic("unexpected panic")
 	}))
 }
+
+func TestIsTrue(t *testing.T) {
+	assert := New(t)
+
+	// reflect.Invalid
+	assert.DeepEqual(isTrue(nil), false)
+
+	// reflect.Slice
+	assert.DeepEqual(isTrue([]int{0}), true)
+	assert.DeepEqual(isTrue([]int{}), false)
+
+	// other kinds
+	assert.DeepEqual(isTrue(1), true)
+	assert.DeepEqual(isTrue(0), false)
+	assert.DeepEqual(isTrue(1.0), true)
+	assert.DeepEqual(isTrue(0.0), false)
+	assert.DeepEqual(isTrue("Hello"), true)
+	assert.DeepEqual(isTrue(""), false)
+	assert.DeepEqual(isTrue(func() {}), true)
+}