Add staticcheck tool

vendor/honnef.co/go/tools/analysis/lint/lint.go

@@ -0,0 +1,221 @@
+// Package lint provides abstractions on top of go/analysis.
+// These abstractions add extra information to analyzes, such as structured documentation and severities.
+package lint
+
+import (
+	"fmt"
+	"go/ast"
+	"go/token"
+	"strings"
+
+	"golang.org/x/tools/go/analysis"
+	"honnef.co/go/tools/analysis/facts/tokenfile"
+)
+
+// Analyzer wraps a go/analysis.Analyzer and provides structured documentation.
+type Analyzer struct {
+	// The analyzer's documentation. Unlike go/analysis.Analyzer.Doc,
+	// this field is structured, providing access to severity, options
+	// etc.
+	Doc      *RawDocumentation
+	Analyzer *analysis.Analyzer
+}
+
+func InitializeAnalyzer(a *Analyzer) *Analyzer {
+	a.Analyzer.Doc = a.Doc.Compile().String()
+	a.Analyzer.URL = "https://staticcheck.dev/docs/checks/#" + a.Analyzer.Name
+	a.Analyzer.Requires = append(a.Analyzer.Requires, tokenfile.Analyzer)
+	return a
+}
+
+// Severity describes the severity of diagnostics reported by an analyzer.
+type Severity int
+
+const (
+	SeverityNone Severity = iota
+	SeverityError
+	SeverityDeprecated
+	SeverityWarning
+	SeverityInfo
+	SeverityHint
+)
+
+// MergeStrategy sets how merge mode should behave for diagnostics of an analyzer.
+type MergeStrategy int
+
+const (
+	MergeIfAny MergeStrategy = iota
+	MergeIfAll
+)
+
+type RawDocumentation struct {
+	Title      string
+	Text       string
+	Before     string
+	After      string
+	Since      string
+	NonDefault bool
+	Options    []string
+	Severity   Severity
+	MergeIf    MergeStrategy
+}
+
+type Documentation struct {
+	Title string
+	Text  string
+
+	TitleMarkdown string
+	TextMarkdown  string
+
+	Before     string
+	After      string
+	Since      string
+	NonDefault bool
+	Options    []string
+	Severity   Severity
+	MergeIf    MergeStrategy
+}
+
+func (doc RawDocumentation) Compile() *Documentation {
+	return &Documentation{
+		Title: strings.TrimSpace(stripMarkdown(doc.Title)),
+		Text:  strings.TrimSpace(stripMarkdown(doc.Text)),
+
+		TitleMarkdown: strings.TrimSpace(toMarkdown(doc.Title)),
+		TextMarkdown:  strings.TrimSpace(toMarkdown(doc.Text)),
+
+		Before:     strings.TrimSpace(doc.Before),
+		After:      strings.TrimSpace(doc.After),
+		Since:      doc.Since,
+		NonDefault: doc.NonDefault,
+		Options:    doc.Options,
+		Severity:   doc.Severity,
+		MergeIf:    doc.MergeIf,
+	}
+}
+
+func toMarkdown(s string) string {
+	return strings.NewReplacer(`\'`, "`", `\"`, "`").Replace(s)
+}
+
+func stripMarkdown(s string) string {
+	return strings.NewReplacer(`\'`, "", `\"`, "'").Replace(s)
+}
+
+func (doc *Documentation) Format(metadata bool) string {
+	return doc.format(false, metadata)
+}
+
+func (doc *Documentation) FormatMarkdown(metadata bool) string {
+	return doc.format(true, metadata)
+}
+
+func (doc *Documentation) format(markdown bool, metadata bool) string {
+	b := &strings.Builder{}
+	if markdown {
+		fmt.Fprintf(b, "%s\n\n", doc.TitleMarkdown)
+		if doc.Text != "" {
+			fmt.Fprintf(b, "%s\n\n", doc.TextMarkdown)
+		}
+	} else {
+		fmt.Fprintf(b, "%s\n\n", doc.Title)
+		if doc.Text != "" {
+			fmt.Fprintf(b, "%s\n\n", doc.Text)
+		}
+	}
+
+	if doc.Before != "" {
+		fmt.Fprintln(b, "Before:")
+		fmt.Fprintln(b, "")
+		for line := range strings.SplitSeq(doc.Before, "\n") {
+			fmt.Fprint(b, "    ", line, "\n")
+		}
+		fmt.Fprintln(b, "")
+		fmt.Fprintln(b, "After:")
+		fmt.Fprintln(b, "")
+		for line := range strings.SplitSeq(doc.After, "\n") {
+			fmt.Fprint(b, "    ", line, "\n")
+		}
+		fmt.Fprintln(b, "")
+	}
+
+	if metadata {
+		fmt.Fprint(b, "Available since\n    ")
+		if doc.Since == "" {
+			fmt.Fprint(b, "unreleased")
+		} else {
+			fmt.Fprintf(b, "%s", doc.Since)
+		}
+		if doc.NonDefault {
+			fmt.Fprint(b, ", non-default")
+		}
+		fmt.Fprint(b, "\n")
+		if len(doc.Options) > 0 {
+			fmt.Fprintf(b, "\nOptions\n")
+			for _, opt := range doc.Options {
+				fmt.Fprintf(b, "    %s", opt)
+			}
+			fmt.Fprint(b, "\n")
+		}
+	}
+
+	return b.String()
+}
+
+func (doc *Documentation) String() string {
+	return doc.Format(true)
+}
+
+// ExhaustiveTypeSwitch panics when called. It can be used to ensure
+// that type switches are exhaustive.
+func ExhaustiveTypeSwitch(v any) {
+	panic(fmt.Sprintf("internal error: unhandled case %T", v))
+}
+
+// A directive is a comment of the form '//lint:<command>
+// [arguments...]'. It represents instructions to the static analysis
+// tool.
+type Directive struct {
+	Command   string
+	Arguments []string
+	Directive *ast.Comment
+	Node      ast.Node
+}
+
+func parseDirective(s string) (cmd string, args []string) {
+	if !strings.HasPrefix(s, "//lint:") {
+		return "", nil
+	}
+	s = strings.TrimPrefix(s, "//lint:")
+	fields := strings.Split(s, " ")
+	return fields[0], fields[1:]
+}
+
+// ParseDirectives extracts all directives from a list of Go files.
+func ParseDirectives(files []*ast.File, fset *token.FileSet) []Directive {
+	var dirs []Directive
+	for _, f := range files {
+		// OPT(dh): in our old code, we skip all the comment map work if we
+		// couldn't find any directives, benchmark if that's actually
+		// worth doing
+		cm := ast.NewCommentMap(fset, f, f.Comments)
+		for node, cgs := range cm {
+			for _, cg := range cgs {
+				for _, c := range cg.List {
+					if !strings.HasPrefix(c.Text, "//lint:") {
+						continue
+					}
+					cmd, args := parseDirective(c.Text)
+					d := Directive{
+						Command:   cmd,
+						Arguments: args,
+						Directive: c,
+						Node:      node,
+					}
+					dirs = append(dirs, d)
+				}
+			}
+		}
+	}
+	return dirs
+}