[release-branch.go1.20] runtime/coverage: avoid non-test coverage profiles in test...

When walking through the set of coverage data files generated from a
"go test -cover" run, it's possible to encounter pods (clumps of data
files) that were generated by a run from an instrumented Go tool (for
example, cmd/compile). Add a guard to the test reporting code to
ensure that it only processes files created by the currently running
test.

Fixes #57924.

Change-Id: I1bb7dce88305e1088162e3cb1df628486ecee1c1
Reviewed-on: https://go-review.googlesource.com/c/go/+/462756
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Than McIntosh <thanm@google.com>
(cherry picked from commit cf70d37967b8447af8305e02ef534c4c5f42d49c)
Reviewed-on: https://go-review.googlesource.com/c/go/+/463417
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Auto-Submit: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>

diff --git a/src/runtime/coverage/testsupport.go b/src/runtime/coverage/testsupport.go
index 1d90ebd7a299bf6bbeef863c272f38d2fa499ef3..a481bbbd9ddaa3065af8d88bd7d1bc3b5228f3c2 100644 (file)
--- a/src/runtime/coverage/testsupport.go
+++ b/src/runtime/coverage/testsupport.go
@@ -15,6 +15,7 @@ import (
        "internal/coverage/pods"
        "io"
        "os"
+       "strings"
 )
 
 // processCoverTestDir is called (via a linknamed reference) from
@@ -80,7 +81,15 @@ func processCoverTestDirInternal(dir string, cfile string, cm string, cpkg strin
                cf:    cformat.NewFormatter(cmode),
                cmode: cmode,
        }
+       // Generate the expected hash string based on the final meta-data
+       // hash for this test, then look only for pods that refer to that
+       // hash (just in case there are multiple instrumented executables
+       // in play). See issue #57924 for more on this.
+       hashstring := fmt.Sprintf("%x", finalHash)
        for _, p := range podlist {
+               if !strings.Contains(p.MetaFile, hashstring) {
+                       continue
+               }
                if err := ts.processPod(p); err != nil {
                        return err
                }