Your IP : 172.28.240.42
// Copyright 2020 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 metrics_test
import (
"bytes"
"flag"
"fmt"
"go/ast"
"go/doc"
"go/doc/comment"
"go/format"
"go/parser"
"go/token"
"internal/diff"
"os"
"regexp"
"runtime/metrics"
"sort"
"strings"
"testing"
_ "unsafe"
)
// Implemented in the runtime.
//
//go:linkname runtime_readMetricNames
func runtime_readMetricNames() []string
func TestNames(t *testing.T) {
// Note that this regexp is promised in the package docs for Description. Do not change.
r := regexp.MustCompile("^(?P<name>/[^:]+):(?P<unit>[^:*/]+(?:[*/][^:*/]+)*)$")
all := metrics.All()
for i, d := range all {
if !r.MatchString(d.Name) {
t.Errorf("name %q does not match regexp %#q", d.Name, r)
}
if i > 0 && all[i-1].Name >= all[i].Name {
t.Fatalf("allDesc not sorted: %s ≥ %s", all[i-1].Name, all[i].Name)
}
}
names := runtime_readMetricNames()
sort.Strings(names)
samples := make([]metrics.Sample, len(names))
for i, name := range names {
samples[i].Name = name
}
metrics.Read(samples)
for _, d := range all {
for len(samples) > 0 && samples[0].Name < d.Name {
t.Errorf("%s: reported by runtime but not listed in All", samples[0].Name)
samples = samples[1:]
}
if len(samples) == 0 || d.Name < samples[0].Name {
t.Errorf("%s: listed in All but not reported by runtime", d.Name)
continue
}
if samples[0].Value.Kind() != d.Kind {
t.Errorf("%s: runtime reports %v but All reports %v", d.Name, samples[0].Value.Kind(), d.Kind)
}
samples = samples[1:]
}
}
func wrap(prefix, text string, width int) string {
doc := &comment.Doc{Content: []comment.Block{&comment.Paragraph{Text: []comment.Text{comment.Plain(text)}}}}
pr := &comment.Printer{TextPrefix: prefix, TextWidth: width}
return string(pr.Text(doc))
}
func formatDesc(t *testing.T) string {
var b strings.Builder
for i, d := range metrics.All() {
if i > 0 {
fmt.Fprintf(&b, "\n")
}
fmt.Fprintf(&b, "%s\n", d.Name)
fmt.Fprintf(&b, "%s", wrap("\t", d.Description, 80-2*8))
}
return b.String()
}
var generate = flag.Bool("generate", false, "update doc.go for go generate")
func TestDocs(t *testing.T) {
want := formatDesc(t)
src, err := os.ReadFile("doc.go")
if err != nil {
t.Fatal(err)
}
fset := token.NewFileSet()
f, err := parser.ParseFile(fset, "doc.go", src, parser.ParseComments)
if err != nil {
t.Fatal(err)
}
fdoc := f.Doc
if fdoc == nil {
t.Fatal("no doc comment in doc.go")
}
pkg, err := doc.NewFromFiles(fset, []*ast.File{f}, "runtime/metrics")
if err != nil {
t.Fatal(err)
}
if pkg.Doc == "" {
t.Fatal("doc.NewFromFiles lost doc comment")
}
doc := new(comment.Parser).Parse(pkg.Doc)
expectCode := false
foundCode := false
updated := false
for _, block := range doc.Content {
switch b := block.(type) {
case *comment.Heading:
expectCode = false
if b.Text[0] == comment.Plain("Supported metrics") {
expectCode = true
}
case *comment.Code:
if expectCode {
foundCode = true
if b.Text != want {
if !*generate {
t.Fatalf("doc comment out of date; use go generate to rebuild\n%s", diff.Diff("old", []byte(b.Text), "want", []byte(want)))
}
b.Text = want
updated = true
}
}
}
}
if !foundCode {
t.Fatalf("did not find Supported metrics list in doc.go")
}
if updated {
fmt.Fprintf(os.Stderr, "go test -generate: writing new doc.go\n")
var buf bytes.Buffer
buf.Write(src[:fdoc.Pos()-f.FileStart])
buf.WriteString("/*\n")
buf.Write(new(comment.Printer).Comment(doc))
buf.WriteString("*/")
buf.Write(src[fdoc.End()-f.FileStart:])
src, err := format.Source(buf.Bytes())
if err != nil {
t.Fatal(err)
}
if err := os.WriteFile("doc.go", src, 0666); err != nil {
t.Fatal(err)
}
} else if *generate {
fmt.Fprintf(os.Stderr, "go test -generate: doc.go already up-to-date\n")
}
}