go.mod: vendor golangci-lint

1 files changed, 163 insertions, 0 deletions

diff --git a/vendor/github.com/golangci/check/cmd/varcheck/varcheck.go b/vendor/github.com/golangci/check/cmd/varcheck/varcheck.go
new file mode 100644
index 000000000..8e93e0473
--- /dev/null
+++ b/vendor/github.com/golangci/check/cmd/varcheck/varcheck.go
@@ -0,0 +1,163 @@
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package varcheck
+
+import (
+	"flag"
+	"go/ast"
+	"go/token"
+	"strings"
+
+	"go/types"
+
+	"golang.org/x/tools/go/loader"
+)
+
+var (
+	buildTags = flag.String("varcheck.tags", "", "Build tags")
+)
+
+type object struct {
+	pkgPath string
+	name    string
+}
+
+type visitor struct {
+	prog       *loader.Program
+	pkg        *loader.PackageInfo
+	uses       map[object]int
+	positions  map[object]token.Position
+	insideFunc bool
+}
+
+func getKey(obj types.Object) object {
+	if obj == nil {
+		return object{}
+	}
+
+	pkg := obj.Pkg()
+	pkgPath := ""
+	if pkg != nil {
+		pkgPath = pkg.Path()
+	}
+
+	return object{
+		pkgPath: pkgPath,
+		name:    obj.Name(),
+	}
+}
+
+func (v *visitor) decl(obj types.Object) {
+	key := getKey(obj)
+	if _, ok := v.uses[key]; !ok {
+		v.uses[key] = 0
+	}
+	if _, ok := v.positions[key]; !ok {
+		v.positions[key] = v.prog.Fset.Position(obj.Pos())
+	}
+}
+
+func (v *visitor) use(obj types.Object) {
+	key := getKey(obj)
+	if _, ok := v.uses[key]; ok {
+		v.uses[key]++
+	} else {
+		v.uses[key] = 1
+	}
+}
+
+func isReserved(name string) bool {
+	return name == "_" || strings.HasPrefix(strings.ToLower(name), "_cgo_")
+}
+
+func (v *visitor) Visit(node ast.Node) ast.Visitor {
+	switch node := node.(type) {
+	case *ast.Ident:
+		v.use(v.pkg.Info.Uses[node])
+
+	case *ast.ValueSpec:
+		if !v.insideFunc {
+			for _, ident := range node.Names {
+				if !isReserved(ident.Name) {
+					v.decl(v.pkg.Info.Defs[ident])
+				}
+			}
+		}
+		for _, val := range node.Values {
+			ast.Walk(v, val)
+		}
+		if node.Type != nil {
+			ast.Walk(v, node.Type)
+		}
+		return nil
+
+	case *ast.FuncDecl:
+		if node.Body != nil {
+			v.insideFunc = true
+			ast.Walk(v, node.Body)
+			v.insideFunc = false
+		}
+
+		if node.Recv != nil {
+			ast.Walk(v, node.Recv)
+		}
+		if node.Type != nil {
+			ast.Walk(v, node.Type)
+		}
+
+		return nil
+	}
+
+	return v
+}
+
+type Issue struct {
+	Pos     token.Position
+	VarName string
+}
+
+func Run(program *loader.Program, reportExported bool) []Issue {
+	var issues []Issue
+	uses := make(map[object]int)
+	positions := make(map[object]token.Position)
+
+	for _, pkgInfo := range program.InitialPackages() {
+		if pkgInfo.Pkg.Path() == "unsafe" {
+			continue
+		}
+
+		v := &visitor{
+			prog:      program,
+			pkg:       pkgInfo,
+			uses:      uses,
+			positions: positions,
+		}
+
+		for _, f := range v.pkg.Files {
+			ast.Walk(v, f)
+		}
+	}
+
+	for obj, useCount := range uses {
+		if useCount == 0 && (reportExported || !ast.IsExported(obj.name)) {
+			pos := positions[obj]
+			issues = append(issues, Issue{
+				Pos:     pos,
+				VarName: obj.name,
+			})
+		}
+	}
+
+	return issues
+}