Add staticcheck tool

vendor/honnef.co/go/tools/stylecheck/st1000/st1000.go

@@ -0,0 +1,83 @@
+package st1000
+
+import (
+	"fmt"
+	"go/ast"
+	"strings"
+
+	"honnef.co/go/tools/analysis/code"
+	"honnef.co/go/tools/analysis/lint"
+	"honnef.co/go/tools/analysis/report"
+
+	"golang.org/x/tools/go/analysis"
+)
+
+var SCAnalyzer = lint.InitializeAnalyzer(&lint.Analyzer{
+	Analyzer: &analysis.Analyzer{
+		Name: "ST1000",
+		Run:  run,
+	},
+	Doc: &lint.RawDocumentation{
+		Title: `Incorrect or missing package comment`,
+		Text: `Packages must have a package comment that is formatted according to
+the guidelines laid out in
+https://go.dev/wiki/CodeReviewComments#package-comments.`,
+		Since:      "2019.1",
+		NonDefault: true,
+		MergeIf:    lint.MergeIfAny,
+	},
+})
+
+var Analyzer = SCAnalyzer.Analyzer
+
+func run(pass *analysis.Pass) (any, error) {
+	// - At least one file in a non-main package should have a package comment
+	//
+	// - The comment should be of the form
+	// "Package x ...". This has a slight potential for false
+	// positives, as multiple files can have package comments, in
+	// which case they get appended. But that doesn't happen a lot in
+	// the real world.
+
+	if pass.Pkg.Name() == "main" {
+		return nil, nil
+	}
+	hasDocs := false
+	for _, f := range pass.Files {
+		if code.IsInTest(pass, f) {
+			continue
+		}
+		text, ok := docText(f.Doc)
+		if ok {
+			hasDocs = true
+			prefix := "Package " + f.Name.Name
+			isNonAlpha := func(b byte) bool {
+				// This check only considers ASCII, which can lead to false negatives for some malformed package
+				// comments.
+				return !((b >= '0' && b <= '9') || (b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z'))
+			}
+			if !strings.HasPrefix(text, prefix) || (len(text) > len(prefix) && !isNonAlpha(text[len(prefix)])) {
+				report.Report(pass, f.Doc, fmt.Sprintf(`package comment should be of the form "%s..."`, prefix))
+			}
+		}
+	}
+
+	if !hasDocs {
+		for _, f := range pass.Files {
+			if code.IsInTest(pass, f) {
+				continue
+			}
+			report.Report(pass, f, "at least one file in a package should have a package comment", report.ShortRange())
+		}
+	}
+	return nil, nil
+}
+
+func docText(doc *ast.CommentGroup) (string, bool) {
+	if doc == nil {
+		return "", false
+	}
+	// We trim spaces primarily because of /**/ style comments, which often have leading space.
+	text := strings.TrimSpace(doc.Text())
+	return text, text != ""
+}