runtime: check that pprof accepts but doesn't need executable

The profiles are self-contained now.
Check that they work by themselves in the tests that invoke pprof,
but also keep checking that the old command lines work.

Change-Id: I24c74b5456f0b50473883c3640625c6612f72309
Reviewed-on: https://go-review.googlesource.com/37166
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>

src/runtime/crash_cgo_test.go

@@ -287,7 +287,14 @@ func testCgoPprof(t *testing.T, buildArg, runArg string) {
 	fn := strings.TrimSpace(string(got))
 	defer os.Remove(fn)
 
-	cmd := testEnv(exec.Command(testenv.GoToolPath(t), "tool", "pprof", "-top", "-nodecount=1", exe, fn))
+	for try := 0; try < 2; try++ {
+		cmd := testEnv(exec.Command(testenv.GoToolPath(t), "tool", "pprof", "-top", "-nodecount=1"))
+		// Check that pprof works both with and without explicit executable on command line.
+		if try == 0 {
+			cmd.Args = append(cmd.Args, exe, fn)
+		} else {
+			cmd.Args = append(cmd.Args, fn)
+		}
 
 		found := false
 		for i, e := range cmd.Env {
@@ -302,14 +309,13 @@ func testCgoPprof(t *testing.T, buildArg, runArg string) {
 		}
 
 		top, err := cmd.CombinedOutput()
-	t.Logf("%s", top)
+		t.Logf("%s:\n%s", cmd.Args, top)
 		if err != nil {
-		t.Fatal(err)
-	}
-
-	if !bytes.Contains(top, []byte("cpuHog")) {
+			t.Error(err)
+		} else if !bytes.Contains(top, []byte("cpuHog")) {
 			t.Error("missing cpuHog in pprof output")
 		}
+	}
 }
 
 func TestCgoPprof(t *testing.T) {

src/runtime/crash_test.go

@@ -476,8 +476,14 @@ func TestMemPprof(t *testing.T) {
 	fn := strings.TrimSpace(string(got))
 	defer os.Remove(fn)
 
-	cmd := testEnv(exec.Command(testenv.GoToolPath(t), "tool", "pprof", "-alloc_space", "-top", exe, fn))
-
+	for try := 0; try < 2; try++ {
+		cmd := testEnv(exec.Command(testenv.GoToolPath(t), "tool", "pprof", "-alloc_space", "-top"))
+		// Check that pprof works both with and without explicit executable on command line.
+		if try == 0 {
+			cmd.Args = append(cmd.Args, exe, fn)
+		} else {
+			cmd.Args = append(cmd.Args, fn)
+		}
 		found := false
 		for i, e := range cmd.Env {
 			if strings.HasPrefix(e, "PPROF_TMPDIR=") {
@@ -491,14 +497,13 @@ func TestMemPprof(t *testing.T) {
 		}
 
 		top, err := cmd.CombinedOutput()
-	t.Logf("%s", top)
+		t.Logf("%s:\n%s", cmd.Args, top)
 		if err != nil {
-		t.Fatal(err)
-	}
-
-	if !bytes.Contains(top, []byte("MemProf")) {
+			t.Error(err)
+		} else if !bytes.Contains(top, []byte("MemProf")) {
 			t.Error("missing MemProf in pprof output")
 		}
+	}
 }
 
 var concurrentMapTest = flag.Bool("run_concurrent_map_tests", false, "also run flaky concurrent map tests")