1 files changed, 107 insertions, 0 deletions
diff --git a/vendor/github.com/mgechev/revive/rule/unnecessary-stmt.go b/vendor/github.com/mgechev/revive/rule/unnecessary-stmt.go
new file mode 100644
index 0000000000..732d8a8bb6
--- /dev/null
+++ b/vendor/github.com/mgechev/revive/rule/unnecessary-stmt.go
@@ -0,0 +1,107 @@
+package rule
+
+import (
+	"go/ast"
+	"go/token"
+
+	"github.com/mgechev/revive/lint"
+)
+
+// UnnecessaryStmtRule warns on unnecessary statements.
+type UnnecessaryStmtRule struct{}
+
+// Apply applies the rule to given file.
+func (r *UnnecessaryStmtRule) Apply(file *lint.File, _ lint.Arguments) []lint.Failure {
+	var failures []lint.Failure
+	onFailure := func(failure lint.Failure) {
+		failures = append(failures, failure)
+	}
+
+	w := lintUnnecessaryStmtRule{onFailure}
+	ast.Walk(w, file.AST)
+	return failures
+}
+
+// Name returns the rule name.
+func (r *UnnecessaryStmtRule) Name() string {
+	return "unnecessary-stmt"
+}
+
+type lintUnnecessaryStmtRule struct {
+	onFailure func(lint.Failure)
+}
+
+func (w lintUnnecessaryStmtRule) Visit(node ast.Node) ast.Visitor {
+	switch n := node.(type) {
+	case *ast.FuncDecl:
+		if n.Body == nil || n.Type.Results != nil {
+			return w
+		}
+		stmts := n.Body.List
+		if len(stmts) == 0 {
+			return w
+		}
+
+		lastStmt := stmts[len(stmts)-1]
+		rs, ok := lastStmt.(*ast.ReturnStmt)
+		if !ok {
+			return w
+		}
+
+		if len(rs.Results) == 0 {
+			w.newFailure(lastStmt, "omit unnecessary return statement")
+		}
+
+	case *ast.SwitchStmt:
+		w.checkSwitchBody(n.Body)
+	case *ast.TypeSwitchStmt:
+		w.checkSwitchBody(n.Body)
+	case *ast.CaseClause:
+		if n.Body == nil {
+			return w
+		}
+		stmts := n.Body
+		if len(stmts) == 0 {
+			return w
+		}
+
+		lastStmt := stmts[len(stmts)-1]
+		rs, ok := lastStmt.(*ast.BranchStmt)
+		if !ok {
+			return w
+		}
+
+		if rs.Tok == token.BREAK && rs.Label == nil {
+			w.newFailure(lastStmt, "omit unnecessary break at the end of case clause")
+		}
+	}
+
+	return w
+}
+
+func (w lintUnnecessaryStmtRule) checkSwitchBody(b *ast.BlockStmt) {
+	cases := b.List
+	if len(cases) != 1 {
+		return
+	}
+
+	cc, ok := cases[0].(*ast.CaseClause)
+	if !ok {
+		return
+	}
+
+	if len(cc.List) > 1 { // skip cases with multiple expressions
+		return
+	}
+
+	w.newFailure(b, "switch with only one case can be replaced by an if-then")
+}
+
+func (w lintUnnecessaryStmtRule) newFailure(node ast.Node, msg string) {
+	w.onFailure(lint.Failure{
+		Confidence: 1,
+		Node:       node,
+		Category:   "style",
+		Failure:    msg,
+	})
+}