--- /dev/null
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package analysisflags defines helpers for processing flags of
+// analysis driver tools.
+package analysisflags
+
+import (
+ "crypto/sha256"
+ "encoding/gob"
+ "encoding/json"
+ "flag"
+ "fmt"
+ "go/token"
+ "io"
+ "io/ioutil"
+ "log"
+ "os"
+ "strconv"
+ "strings"
+
+ "golang.org/x/tools/go/analysis"
+)
+
+// flags common to all {single,multi,unit}checkers.
+var (
+ JSON = false // -json
+ Context = -1 // -c=N: if N>0, display offending line plus N lines of context
+)
+
+// Parse creates a flag for each of the analyzer's flags,
+// including (in multi mode) a flag named after the analyzer,
+// parses the flags, then filters and returns the list of
+// analyzers enabled by flags.
+//
+// The result is intended to be passed to unitchecker.Run or checker.Run.
+// Use in unitchecker.Run will gob.Register all fact types for the returned
+// graph of analyzers but of course not the ones only reachable from
+// dropped analyzers. To avoid inconsistency about which gob types are
+// registered from run to run, Parse itself gob.Registers all the facts
+// only reachable from dropped analyzers.
+// This is not a particularly elegant API, but this is an internal package.
+func Parse(analyzers []*analysis.Analyzer, multi bool) []*analysis.Analyzer {
+ // Connect each analysis flag to the command line as -analysis.flag.
+ enabled := make(map[*analysis.Analyzer]*triState)
+ for _, a := range analyzers {
+ var prefix string
+
+ // Add -NAME flag to enable it.
+ if multi {
+ prefix = a.Name + "."
+
+ enable := new(triState)
+ enableUsage := "enable " + a.Name + " analysis"
+ flag.Var(enable, a.Name, enableUsage)
+ enabled[a] = enable
+ }
+
+ a.Flags.VisitAll(func(f *flag.Flag) {
+ if !multi && flag.Lookup(f.Name) != nil {
+ log.Printf("%s flag -%s would conflict with driver; skipping", a.Name, f.Name)
+ return
+ }
+
+ name := prefix + f.Name
+ flag.Var(f.Value, name, f.Usage)
+ })
+ }
+
+ // standard flags: -flags, -V.
+ printflags := flag.Bool("flags", false, "print analyzer flags in JSON")
+ addVersionFlag()
+
+ // flags common to all checkers
+ flag.BoolVar(&JSON, "json", JSON, "emit JSON output")
+ flag.IntVar(&Context, "c", Context, `display offending line with this many lines of context`)
+
+ // Add shims for legacy vet flags to enable existing
+ // scripts that run vet to continue to work.
+ _ = flag.Bool("source", false, "no effect (deprecated)")
+ _ = flag.Bool("v", false, "no effect (deprecated)")
+ _ = flag.Bool("all", false, "no effect (deprecated)")
+ _ = flag.String("tags", "", "no effect (deprecated)")
+ for old, new := range vetLegacyFlags {
+ newFlag := flag.Lookup(new)
+ if newFlag != nil && flag.Lookup(old) == nil {
+ flag.Var(newFlag.Value, old, "deprecated alias for -"+new)
+ }
+ }
+
+ flag.Parse() // (ExitOnError)
+
+ // -flags: print flags so that go vet knows which ones are legitimate.
+ if *printflags {
+ printFlags()
+ os.Exit(0)
+ }
+
+ everything := expand(analyzers)
+
+ // If any -NAME flag is true, run only those analyzers. Otherwise,
+ // if any -NAME flag is false, run all but those analyzers.
+ if multi {
+ var hasTrue, hasFalse bool
+ for _, ts := range enabled {
+ switch *ts {
+ case setTrue:
+ hasTrue = true
+ case setFalse:
+ hasFalse = true
+ }
+ }
+
+ var keep []*analysis.Analyzer
+ if hasTrue {
+ for _, a := range analyzers {
+ if *enabled[a] == setTrue {
+ keep = append(keep, a)
+ }
+ }
+ analyzers = keep
+ } else if hasFalse {
+ for _, a := range analyzers {
+ if *enabled[a] != setFalse {
+ keep = append(keep, a)
+ }
+ }
+ analyzers = keep
+ }
+ }
+
+ // Register fact types of skipped analyzers
+ // in case we encounter them in imported files.
+ kept := expand(analyzers)
+ for a := range everything {
+ if !kept[a] {
+ for _, f := range a.FactTypes {
+ gob.Register(f)
+ }
+ }
+ }
+
+ return analyzers
+}
+
+func expand(analyzers []*analysis.Analyzer) map[*analysis.Analyzer]bool {
+ seen := make(map[*analysis.Analyzer]bool)
+ var visitAll func([]*analysis.Analyzer)
+ visitAll = func(analyzers []*analysis.Analyzer) {
+ for _, a := range analyzers {
+ if !seen[a] {
+ seen[a] = true
+ visitAll(a.Requires)
+ }
+ }
+ }
+ visitAll(analyzers)
+ return seen
+}
+
+func printFlags() {
+ type jsonFlag struct {
+ Name string
+ Bool bool
+ Usage string
+ }
+ var flags []jsonFlag = nil
+ flag.VisitAll(func(f *flag.Flag) {
+ // Don't report {single,multi}checker debugging
+ // flags or fix as these have no effect on unitchecker
+ // (as invoked by 'go vet').
+ switch f.Name {
+ case "debug", "cpuprofile", "memprofile", "trace", "fix":
+ return
+ }
+
+ b, ok := f.Value.(interface{ IsBoolFlag() bool })
+ isBool := ok && b.IsBoolFlag()
+ flags = append(flags, jsonFlag{f.Name, isBool, f.Usage})
+ })
+ data, err := json.MarshalIndent(flags, "", "\t")
+ if err != nil {
+ log.Fatal(err)
+ }
+ os.Stdout.Write(data)
+}
+
+// addVersionFlag registers a -V flag that, if set,
+// prints the executable version and exits 0.
+//
+// If the -V flag already exists — for example, because it was already
+// registered by a call to cmd/internal/objabi.AddVersionFlag — then
+// addVersionFlag does nothing.
+func addVersionFlag() {
+ if flag.Lookup("V") == nil {
+ flag.Var(versionFlag{}, "V", "print version and exit")
+ }
+}
+
+// versionFlag minimally complies with the -V protocol required by "go vet".
+type versionFlag struct{}
+
+func (versionFlag) IsBoolFlag() bool { return true }
+func (versionFlag) Get() interface{} { return nil }
+func (versionFlag) String() string { return "" }
+func (versionFlag) Set(s string) error {
+ if s != "full" {
+ log.Fatalf("unsupported flag value: -V=%s", s)
+ }
+
+ // This replicates the minimal subset of
+ // cmd/internal/objabi.AddVersionFlag, which is private to the
+ // go tool yet forms part of our command-line interface.
+ // TODO(adonovan): clarify the contract.
+
+ // Print the tool version so the build system can track changes.
+ // Formats:
+ // $progname version devel ... buildID=...
+ // $progname version go1.9.1
+ progname := os.Args[0]
+ f, err := os.Open(progname)
+ if err != nil {
+ log.Fatal(err)
+ }
+ h := sha256.New()
+ if _, err := io.Copy(h, f); err != nil {
+ log.Fatal(err)
+ }
+ f.Close()
+ fmt.Printf("%s version devel comments-go-here buildID=%02x\n",
+ progname, string(h.Sum(nil)))
+ os.Exit(0)
+ return nil
+}
+
+// A triState is a boolean that knows whether
+// it has been set to either true or false.
+// It is used to identify whether a flag appears;
+// the standard boolean flag cannot
+// distinguish missing from unset.
+// It also satisfies flag.Value.
+type triState int
+
+const (
+ unset triState = iota
+ setTrue
+ setFalse
+)
+
+func triStateFlag(name string, value triState, usage string) *triState {
+ flag.Var(&value, name, usage)
+ return &value
+}
+
+// triState implements flag.Value, flag.Getter, and flag.boolFlag.
+// They work like boolean flags: we can say vet -printf as well as vet -printf=true
+func (ts *triState) Get() interface{} {
+ return *ts == setTrue
+}
+
+func (ts triState) isTrue() bool {
+ return ts == setTrue
+}
+
+func (ts *triState) Set(value string) error {
+ b, err := strconv.ParseBool(value)
+ if err != nil {
+ // This error message looks poor but package "flag" adds
+ // "invalid boolean value %q for -NAME: %s"
+ return fmt.Errorf("want true or false")
+ }
+ if b {
+ *ts = setTrue
+ } else {
+ *ts = setFalse
+ }
+ return nil
+}
+
+func (ts *triState) String() string {
+ switch *ts {
+ case unset:
+ return "true"
+ case setTrue:
+ return "true"
+ case setFalse:
+ return "false"
+ }
+ panic("not reached")
+}
+
+func (ts triState) IsBoolFlag() bool {
+ return true
+}
+
+// Legacy flag support
+
+// vetLegacyFlags maps flags used by legacy vet to their corresponding
+// new names. The old names will continue to work.
+var vetLegacyFlags = map[string]string{
+ // Analyzer name changes
+ "bool": "bools",
+ "buildtags": "buildtag",
+ "methods": "stdmethods",
+ "rangeloops": "loopclosure",
+
+ // Analyzer flags
+ "compositewhitelist": "composites.whitelist",
+ "printfuncs": "printf.funcs",
+ "shadowstrict": "shadow.strict",
+ "unusedfuncs": "unusedresult.funcs",
+ "unusedstringmethods": "unusedresult.stringmethods",
+}
+
+// ---- output helpers common to all drivers ----
+
+// PrintPlain prints a diagnostic in plain text form,
+// with context specified by the -c flag.
+func PrintPlain(fset *token.FileSet, diag analysis.Diagnostic) {
+ posn := fset.Position(diag.Pos)
+ fmt.Fprintf(os.Stderr, "%s: %s\n", posn, diag.Message)
+
+ // -c=N: show offending line plus N lines of context.
+ if Context >= 0 {
+ posn := fset.Position(diag.Pos)
+ end := fset.Position(diag.End)
+ if !end.IsValid() {
+ end = posn
+ }
+ data, _ := ioutil.ReadFile(posn.Filename)
+ lines := strings.Split(string(data), "\n")
+ for i := posn.Line - Context; i <= end.Line+Context; i++ {
+ if 1 <= i && i <= len(lines) {
+ fmt.Fprintf(os.Stderr, "%d\t%s\n", i, lines[i-1])
+ }
+ }
+ }
+}
+
+// A JSONTree is a mapping from package ID to analysis name to result.
+// Each result is either a jsonError or a list of jsonDiagnostic.
+type JSONTree map[string]map[string]interface{}
+
+// Add adds the result of analysis 'name' on package 'id'.
+// The result is either a list of diagnostics or an error.
+func (tree JSONTree) Add(fset *token.FileSet, id, name string, diags []analysis.Diagnostic, err error) {
+ var v interface{}
+ if err != nil {
+ type jsonError struct {
+ Err string `json:"error"`
+ }
+ v = jsonError{err.Error()}
+ } else if len(diags) > 0 {
+ type jsonDiagnostic struct {
+ Category string `json:"category,omitempty"`
+ Posn string `json:"posn"`
+ Message string `json:"message"`
+ }
+ var diagnostics []jsonDiagnostic
+ // TODO(matloob): Should the JSON diagnostics contain ranges?
+ // If so, how should they be formatted?
+ for _, f := range diags {
+ diagnostics = append(diagnostics, jsonDiagnostic{
+ Category: f.Category,
+ Posn: fset.Position(f.Pos).String(),
+ Message: f.Message,
+ })
+ }
+ v = diagnostics
+ }
+ if v != nil {
+ m, ok := tree[id]
+ if !ok {
+ m = make(map[string]interface{})
+ tree[id] = m
+ }
+ m[name] = v
+ }
+}
+
+func (tree JSONTree) Print() {
+ data, err := json.MarshalIndent(tree, "", "\t")
+ if err != nil {
+ log.Panicf("internal error: JSON marshaling failed: %v", err)
+ }
+ fmt.Printf("%s\n", data)
+}
projects / dotfiles / .git / blobdiff