diff options
Diffstat (limited to 'vendor/github.com/mgechev/revive/rule/bool-literal-in-expr.go')
-rw-r--r-- | vendor/github.com/mgechev/revive/rule/bool-literal-in-expr.go | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/vendor/github.com/mgechev/revive/rule/bool-literal-in-expr.go b/vendor/github.com/mgechev/revive/rule/bool-literal-in-expr.go new file mode 100644 index 0000000000..0a4e696c63 --- /dev/null +++ b/vendor/github.com/mgechev/revive/rule/bool-literal-in-expr.go @@ -0,0 +1,73 @@ +package rule + +import ( + "go/ast" + "go/token" + + "github.com/mgechev/revive/lint" +) + +// BoolLiteralRule warns when logic expressions contains Boolean literals. +type BoolLiteralRule struct{} + +// Apply applies the rule to given file. +func (r *BoolLiteralRule) Apply(file *lint.File, _ lint.Arguments) []lint.Failure { + var failures []lint.Failure + + onFailure := func(failure lint.Failure) { + failures = append(failures, failure) + } + + astFile := file.AST + w := &lintBoolLiteral{astFile, onFailure} + ast.Walk(w, astFile) + + return failures +} + +// Name returns the rule name. +func (r *BoolLiteralRule) Name() string { + return "bool-literal-in-expr" +} + +type lintBoolLiteral struct { + file *ast.File + onFailure func(lint.Failure) +} + +func (w *lintBoolLiteral) Visit(node ast.Node) ast.Visitor { + switch n := node.(type) { + case *ast.BinaryExpr: + if !isBoolOp(n.Op) { + return w + } + + lexeme, ok := isExprABooleanLit(n.X) + if !ok { + lexeme, ok = isExprABooleanLit(n.Y) + + if !ok { + return w + } + } + + isConstant := (n.Op == token.LAND && lexeme == "false") || (n.Op == token.LOR && lexeme == "true") + + if isConstant { + w.addFailure(n, "Boolean expression seems to always evaluate to "+lexeme, "logic") + } else { + w.addFailure(n, "omit Boolean literal in expression", "style") + } + } + + return w +} + +func (w lintBoolLiteral) addFailure(node ast.Node, msg string, cat string) { + w.onFailure(lint.Failure{ + Confidence: 1, + Node: node, + Category: cat, + Failure: msg, + }) +} |