package rule import ( "fmt" "github.com/mgechev/revive/internal/ifelse" "github.com/mgechev/revive/lint" ) // SuperfluousElseRule lints given else constructs. type SuperfluousElseRule struct{} // Apply applies the rule to given file. func (e *SuperfluousElseRule) Apply(file *lint.File, args lint.Arguments) []lint.Failure { return ifelse.Apply(e, file.AST, ifelse.TargetElse, args) } // Name returns the rule name. func (*SuperfluousElseRule) Name() string { return "superfluous-else" } // CheckIfElse evaluates the rule against an ifelse.Chain and returns a failure message if applicable. func (*SuperfluousElseRule) CheckIfElse(chain ifelse.Chain, args ifelse.Args) string { if !chain.If.Deviates() { // this rule only applies if the if-block deviates control flow return "" } if chain.HasPriorNonDeviating { // if we de-indent the "else" block then a previous branch // might flow into it, affecting program behaviour return "" } if chain.If.Returns() { // avoid overlapping with indent-error-flow return "" } if args.PreserveScope && !chain.AtBlockEnd && (chain.HasInitializer || chain.Else.HasDecls) { // avoid increasing variable scope return "" } return fmt.Sprintf("if block ends with %v, so drop this else and outdent its block", chain.If.LongString()) }