cmd/go: correctly quote environment variables in -x output

This fixes the -x output so that when it reports environment variables they
are correctly quoted for later execution by the shell.
Also fix -x output to use the right path to the pack tool, and note when
we are touching a file.

Fixes #21427

Change-Id: I323ef4edf9905b08bc26944b94183d8da2fa9675
Reviewed-on: https://go-review.googlesource.com/55350
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

diff --git a/src/cmd/go/go_test.go b/src/cmd/go/go_test.go
index 2006283ea18485695e991e9baad8ff38348038e8..56b9b07889b3f96e12b57a4885fe5bb093374dca 100644 (file)
--- a/src/cmd/go/go_test.go
+++ b/src/cmd/go/go_test.go
@@ -4389,3 +4389,52 @@ func TestBuildmodePIE(t *testing.T) {
                t.Errorf("got %q; want %q", out, "hello")
        }
 }
+
+func TestExecBuildX(t *testing.T) {
+       if !canCgo {
+               t.Skip("skipping because cgo not enabled")
+       }
+
+       if runtime.GOOS == "plan9" || runtime.GOOS == "windows" {
+               t.Skipf("skipping because unix shell is not supported on %s", runtime.GOOS)
+       }
+
+       tg := testgo(t)
+       defer tg.cleanup()
+
+       tg.tempFile("main.go", `package main; import "C"; func main() { print("hello") }`)
+       src := tg.path("main.go")
+       obj := tg.path("main")
+       tg.run("build", "-x", "-o", obj, src)
+       sh := tg.path("test.sh")
+       err := ioutil.WriteFile(sh, []byte(tg.getStderr()), 0666)
+       if err != nil {
+               t.Fatal(err)
+       }
+
+       out, err := exec.Command(obj).CombinedOutput()
+       if err != nil {
+               t.Fatal(err)
+       }
+       if string(out) != "hello" {
+               t.Fatalf("got %q; want %q", out, "hello")
+       }
+
+       err = os.Remove(obj)
+       if err != nil {
+               t.Fatal(err)
+       }
+
+       out, err = exec.Command("/bin/sh", sh).CombinedOutput()
+       if err != nil {
+               t.Fatalf("/bin/sh %s: %v\n%s", sh, err, out)
+       }
+
+       out, err = exec.Command(obj).CombinedOutput()
+       if err != nil {
+               t.Fatal(err)
+       }
+       if string(out) != "hello" {
+               t.Fatalf("got %q; want %q", out, "hello")
+       }
+}

diff --git a/src/cmd/go/internal/work/build.go b/src/cmd/go/internal/work/build.go
index 53afebe8cca919e28a891920ddf057921f1166fd..400186307ed3b08b7ac8121bce0cffdd7eb9537a 100644 (file)
--- a/src/cmd/go/internal/work/build.go
+++ b/src/cmd/go/internal/work/build.go
@@ -1963,9 +1963,15 @@ func (b *Builder) runOut(dir string, desc string, env []string, cmdargs ...inter
        cmdline := str.StringList(cmdargs...)
        if cfg.BuildN || cfg.BuildX {
                var envcmdline string
-               for i := range env {
-                       envcmdline += env[i]
-                       envcmdline += " "
+               for _, e := range env {
+                       if j := strings.IndexByte(e, '='); j != -1 {
+                               if strings.ContainsRune(e[j+1:], '\'') {
+                                       envcmdline += fmt.Sprintf("%s=%q", e[:j], e[j+1:])
+                               } else {
+                                       envcmdline += fmt.Sprintf("%s='%s'", e[:j], e[j+1:])
+                               }
+                               envcmdline += " "
+                       }
                }
                envcmdline += joinUnambiguously(cmdline)
                b.Showcmd(dir, "%s", envcmdline)
@@ -2416,7 +2422,7 @@ func (gcToolchain) pack(b *Builder, p *load.Package, objDir, afile string, ofile
        }
 
        if cfg.BuildN || cfg.BuildX {
-               cmdline := str.StringList("pack", "r", absAfile, absOfiles)
+               cmdline := str.StringList(base.Tool("pack"), "r", absAfile, absOfiles)
                b.Showcmd(p.Dir, "%s # internal", joinUnambiguously(cmdline))
        }
        if cfg.BuildN {
@@ -3220,6 +3226,9 @@ func (b *Builder) gccSupportsFlag(flag string) bool {
                return b
        }
        if b.flagCache == nil {
+               if cfg.BuildN || cfg.BuildX {
+                       b.Showcmd(b.WorkDir, "touch trivial.c")
+               }
                src := filepath.Join(b.WorkDir, "trivial.c")
                if err := ioutil.WriteFile(src, []byte{}, 0666); err != nil {
                        return false