go/importer: disable TestForCompiler/LookupCustom for GOEXPERIMENT=unified

The TestForCompiler/LookupCustom test tries to read in the export data
for "math/big", but with a package path of "math/bigger" instead. This
has historically worked because the export data formats were designed
to not assume the package's own path, but I expect we can safely
remove support for this now.

However, since that would be a user-visible change, for now just
disable the test for GOEXPERIMENT=unified so we can land CL 393715. We
can revisit whether it's actually safe to break that go/importer use
case later.

Updates #51734.

Change-Id: I5e89314511bd1352a9f5e14a2e218a5ab00cab3c
Reviewed-on: https://go-review.googlesource.com/c/go/+/406319
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>

diff --git a/src/go/importer/importer_test.go b/src/go/importer/importer_test.go
index 91b656a88c9434a9b54db26741a570ae629c9fc6..1b8353e8fa63af863a63ec8ea200f291c0c2f24e 100644 (file)
--- a/src/go/importer/importer_test.go
+++ b/src/go/importer/importer_test.go
@@ -7,6 +7,7 @@ package importer
 import (
        "go/build"
        "go/token"
+       "internal/buildcfg"
        "internal/testenv"
        "io"
        "os"
@@ -67,6 +68,14 @@ func TestForCompiler(t *testing.T) {
        })
 
        t.Run("LookupCustom", func(t *testing.T) {
+               // TODO(mdempsky): Decide whether to remove this test, or to fix
+               // support for it in unified IR. It's not clear that we actually
+               // need to support importing "math/big" as "math/bigger", for
+               // example. cmd/link no longer supports that.
+               if buildcfg.Experiment.Unified {
+                       t.Skip("not supported by GOEXPERIMENT=unified; see go.dev/cl/406319")
+               }
+
                lookup := func(path string) (io.ReadCloser, error) {
                        if path != "math/bigger" {
                                t.Fatalf("lookup called with unexpected path %q", path)