package matchers import ( "fmt" "strings" "github.com/onsi/gomega/format" ) type ContainSubstringMatcher struct { Substr string Args []interface{} } func (matcher *ContainSubstringMatcher) Match(actual interface{}) (success bool, err error) { actualString, ok := toString(actual) if !ok { return false, fmt.Errorf("ContainSubstring matcher requires a string or stringer. Got:\n%s", format.Object(actual, 1)) } return strings.Contains(actualString, matcher.stringToMatch()), nil } func (matcher *ContainSubstringMatcher) stringToMatch() string { stringToMatch := matcher.Substr if len(matcher.Args) > 0 { stringToMatch = fmt.Sprintf(matcher.Substr, matcher.Args...) } return stringToMatch } func (matcher *ContainSubstringMatcher) FailureMessage(actual interface{}) (message string) { return format.Message(actual, "to contain substring", matcher.stringToMatch()) } func (matcher *ContainSubstringMatcher) NegatedFailureMessage(actual interface{}) (message string) { return format.Message(actual, "not to contain substring", matcher.stringToMatch()) }