Add staticcheck tool

vendor/honnef.co/go/tools/simple/s1002/s1002.go

@@ -0,0 +1,88 @@
+package s1002
+
+import (
+	"fmt"
+	"go/ast"
+	"go/token"
+	"go/types"
+	"strings"
+
+	"honnef.co/go/tools/analysis/code"
+	"honnef.co/go/tools/analysis/edit"
+	"honnef.co/go/tools/analysis/facts/generated"
+	"honnef.co/go/tools/analysis/lint"
+	"honnef.co/go/tools/analysis/report"
+	"honnef.co/go/tools/go/types/typeutil"
+
+	"golang.org/x/tools/go/analysis"
+	"golang.org/x/tools/go/analysis/passes/inspect"
+)
+
+var SCAnalyzer = lint.InitializeAnalyzer(&lint.Analyzer{
+	Analyzer: &analysis.Analyzer{
+		Name:     "S1002",
+		Run:      run,
+		Requires: []*analysis.Analyzer{inspect.Analyzer, generated.Analyzer},
+	},
+	Doc: &lint.RawDocumentation{
+		Title:  `Omit comparison with boolean constant`,
+		Before: `if x == true {}`,
+		After:  `if x {}`,
+		Since:  "2017.1",
+		// MergeIfAll because 'true' might not be the builtin constant under all build tags.
+		// You shouldn't write code like that…
+		MergeIf: lint.MergeIfAll,
+	},
+})
+
+var Analyzer = SCAnalyzer.Analyzer
+
+func run(pass *analysis.Pass) (any, error) {
+	fn := func(node ast.Node) {
+		if code.IsInTest(pass, node) {
+			return
+		}
+
+		expr := node.(*ast.BinaryExpr)
+		if expr.Op != token.EQL && expr.Op != token.NEQ {
+			return
+		}
+		x := code.IsBoolConst(pass, expr.X)
+		y := code.IsBoolConst(pass, expr.Y)
+		if !x && !y {
+			return
+		}
+		var other ast.Expr
+		var val bool
+		if x {
+			val = code.BoolConst(pass, expr.X)
+			other = expr.Y
+		} else {
+			val = code.BoolConst(pass, expr.Y)
+			other = expr.X
+		}
+
+		ok := typeutil.All(pass.TypesInfo.TypeOf(other), func(term *types.Term) bool {
+			basic, ok := term.Type().Underlying().(*types.Basic)
+			return ok && basic.Kind() == types.Bool
+		})
+		if !ok {
+			return
+		}
+		op := ""
+		if (expr.Op == token.EQL && !val) || (expr.Op == token.NEQ && val) {
+			op = "!"
+		}
+		r := op + report.Render(pass, other)
+		l1 := len(r)
+		r = strings.TrimLeft(r, "!")
+		if (l1-len(r))%2 == 1 {
+			r = "!" + r
+		}
+		report.Report(pass, expr, fmt.Sprintf("should omit comparison to bool constant, can be simplified to %s", r),
+			report.FilterGenerated(),
+			report.Fixes(edit.Fix("Simplify bool comparison", edit.ReplaceWithString(expr, r))))
+	}
+	code.Preorder(pass, fn, (*ast.BinaryExpr)(nil))
+	return nil, nil
+}