1// Copyright 2019 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5//go:build !js && !wasip1
6
7// TODO(@musiol, @odeke-em): re-unify this entire file back into
8// example.go when js/wasm gets an os.Pipe implementation
9// and no longer needs this separation.
10
11package testing
12
13import (
14	"fmt"
15	"io"
16	"os"
17	"strings"
18	"time"
19)
20
21func runExample(eg InternalExample) (ok bool) {
22	if chatty.on {
23		fmt.Printf("%s=== RUN   %s\n", chatty.prefix(), eg.Name)
24	}
25
26	// Capture stdout.
27	stdout := os.Stdout
28	r, w, err := os.Pipe()
29	if err != nil {
30		fmt.Fprintln(os.Stderr, err)
31		os.Exit(1)
32	}
33	os.Stdout = w
34	outC := make(chan string)
35	go func() {
36		var buf strings.Builder
37		_, err := io.Copy(&buf, r)
38		r.Close()
39		if err != nil {
40			fmt.Fprintf(os.Stderr, "testing: copying pipe: %v\n", err)
41			os.Exit(1)
42		}
43		outC <- buf.String()
44	}()
45
46	finished := false
47	start := time.Now()
48
49	// Clean up in a deferred call so we can recover if the example panics.
50	defer func() {
51		timeSpent := time.Since(start)
52
53		// Close pipe, restore stdout, get output.
54		w.Close()
55		os.Stdout = stdout
56		out := <-outC
57
58		err := recover()
59		ok = eg.processRunResult(out, timeSpent, finished, err)
60	}()
61
62	// Run example.
63	eg.F()
64	finished = true
65	return
66}
67