testing: enable examples on js/wasm with non os.Pipe runExample

os.Pipe is not implemented on wasm/js so for that purpose use
a temporary file for js/wasm. This change creates two versions
of runExample:

* runExample verbatim that still uses os.Pipe for non js/wasm
* runExample that uses a temporary file

Also added a TODO to re-unify these function versions back into
example.go wasm/js gets an os.Pipe implementation.

Change-Id: I9f418a49b2c397e1667724c7442b7bbe8942225e
Reviewed-on: https://go-review.googlesource.com/c/go/+/165357
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This commit is contained in:
Emmanuel T Odeke 2019-03-05 03:58:37 -08:00 committed by Brad Fitzpatrick
parent 48d3c32ba9
commit ac56baa09f
3 changed files with 170 additions and 62 deletions

View file

@ -6,7 +6,6 @@ package testing
import (
"fmt"
"io"
"os"
"sort"
"strings"
@ -56,68 +55,39 @@ func sortLines(output string) string {
return strings.Join(lines, "\n")
}
func runExample(eg InternalExample) (ok bool) {
if *chatty {
fmt.Printf("=== RUN %s\n", eg.Name)
// processRunResult computes a summary and status of the result of running an example test.
// stdout is the captured output from stdout of the test.
// recovered is the result of invoking recover after running the test, in case it panicked.
//
// If stdout doesn't match the expected output or if recovered is non-nil, it'll print the cause of failure to stdout.
// If the test is chatty/verbose, it'll print a success message to stdout.
// If recovered is non-nil, it'll panic with that value.
func (eg *InternalExample) processRunResult(stdout string, timeSpent time.Duration, recovered interface{}) (passed bool) {
passed = true
dstr := fmtDuration(timeSpent)
var fail string
got := strings.TrimSpace(stdout)
want := strings.TrimSpace(eg.Output)
if eg.Unordered {
if sortLines(got) != sortLines(want) && recovered == nil {
fail = fmt.Sprintf("got:\n%s\nwant (unordered):\n%s\n", stdout, eg.Output)
}
} else {
if got != want && recovered == nil {
fail = fmt.Sprintf("got:\n%s\nwant:\n%s\n", got, want)
}
}
if fail != "" || recovered != nil {
fmt.Printf("--- FAIL: %s (%s)\n%s", eg.Name, dstr, fail)
passed = false
} else if *chatty {
fmt.Printf("--- PASS: %s (%s)\n", eg.Name, dstr)
}
if recovered != nil {
// Propagate the previously recovered result, by panicking.
panic(recovered)
}
// Capture stdout.
stdout := os.Stdout
r, w, err := os.Pipe()
if err != nil {
fmt.Fprintln(os.Stderr, err)
os.Exit(1)
}
os.Stdout = w
outC := make(chan string)
go func() {
var buf strings.Builder
_, err := io.Copy(&buf, r)
r.Close()
if err != nil {
fmt.Fprintf(os.Stderr, "testing: copying pipe: %v\n", err)
os.Exit(1)
}
outC <- buf.String()
}()
start := time.Now()
ok = true
// Clean up in a deferred call so we can recover if the example panics.
defer func() {
dstr := fmtDuration(time.Since(start))
// Close pipe, restore stdout, get output.
w.Close()
os.Stdout = stdout
out := <-outC
var fail string
err := recover()
got := strings.TrimSpace(out)
want := strings.TrimSpace(eg.Output)
if eg.Unordered {
if sortLines(got) != sortLines(want) && err == nil {
fail = fmt.Sprintf("got:\n%s\nwant (unordered):\n%s\n", out, eg.Output)
}
} else {
if got != want && err == nil {
fail = fmt.Sprintf("got:\n%s\nwant:\n%s\n", got, want)
}
}
if fail != "" || err != nil {
fmt.Printf("--- FAIL: %s (%s)\n%s", eg.Name, dstr, fail)
ok = false
} else if *chatty {
fmt.Printf("--- PASS: %s (%s)\n", eg.Name, dstr)
}
if err != nil {
panic(err)
}
}()
// Run example.
eg.F()
return
}