diff --git a/src/cmd/addr2line/addr2line_test.go b/src/cmd/addr2line/addr2line_test.go
index 22bf1379bb72147c6ccbf72603e4fc8654356478..183a22f8f378ff188c4646c0fc237ef0d5315118 100644
--- a/src/cmd/addr2line/addr2line_test.go
+++ b/src/cmd/addr2line/addr2line_test.go
@@ -115,3 +115,5 @@ func TestAddr2Line(t *testing.T) {
testAddr2Line(t, exepath, syms[symName])
testAddr2Line(t, exepath, "0x"+syms[symName])
}
+
+func init() { testenv.SetModVendor() }
diff --git a/src/cmd/compile/internal/gc/scope_test.go b/src/cmd/compile/internal/gc/scope_test.go
index e327dc02af2df236e93d5c3eafe54aff21b10ac1..e4861c686cdf4e1a67f57c809f0b5141f0bb34bc 100644
--- a/src/cmd/compile/internal/gc/scope_test.go
+++ b/src/cmd/compile/internal/gc/scope_test.go
@@ -202,6 +202,8 @@ var testfile = []testline{
const detailOutput = false
+func init() { testenv.SetModVendor() }
+
// Compiles testfile checks that the description of lexical blocks emitted
// by the linker in debug_info, for each function in the main package,
// corresponds to what we expect it to be.
diff --git a/src/cmd/cover/cover_test.go b/src/cmd/cover/cover_test.go
index f002442b638fb758edb5beaf23c37192a297ff02..d7e6ca99b7fd63af3b7ee26cc2e17e89ac9855a0 100644
--- a/src/cmd/cover/cover_test.go
+++ b/src/cmd/cover/cover_test.go
@@ -77,6 +77,8 @@ var debug = flag.Bool("debug", false, "keep rewritten files for debugging")
// We use TestMain to set up a temporary directory and remove it when
// the tests are done.
func TestMain(m *testing.M) {
+ testenv.SetModVendor()
+
dir, err := ioutil.TempDir("", "gotestcover")
if err != nil {
fmt.Fprintln(os.Stderr, err)
diff --git a/src/cmd/go/go_test.go b/src/cmd/go/go_test.go
index dfada6c806a6c7edf44a0a068d6850c05083f4ab..9ba52e609e1ef67492a522df20fd267586224f85 100644
--- a/src/cmd/go/go_test.go
+++ b/src/cmd/go/go_test.go
@@ -212,7 +212,9 @@ func TestMain(m *testing.M) {
return
}
- out, err := exec.Command(gotool, args...).CombinedOutput()
+ buildCmd := exec.Command(gotool, args...)
+ buildCmd.Env = append(os.Environ(), "GOFLAGS=-mod=vendor")
+ out, err := buildCmd.CombinedOutput()
if err != nil {
fmt.Fprintf(os.Stderr, "building testgo failed: %v\n%s", err, out)
os.Exit(2)
diff --git a/src/cmd/internal/obj/x86/obj6_test.go b/src/cmd/internal/obj/x86/obj6_test.go
index c5399744f2d18761e4a03af33018d6b715051fca..2b1a729c8fcfc89d9e33d446147ebd15e08ec145 100644
--- a/src/cmd/internal/obj/x86/obj6_test.go
+++ b/src/cmd/internal/obj/x86/obj6_test.go
@@ -134,6 +134,8 @@ func parseOutput(t *testing.T, td *ParsedTestData, asmout []byte) {
}
}
+func init() { testenv.SetModVendor() }
+
func TestDynlink(t *testing.T) {
testenv.MustHaveGoBuild(t)
diff --git a/src/cmd/link/internal/ld/ld_test.go b/src/cmd/link/internal/ld/ld_test.go
index 081642931652bafe9a34750acfd8677cd2108445..219b2a63cacc060e6df9ae88483e4cd0c4ff2781 100644
--- a/src/cmd/link/internal/ld/ld_test.go
+++ b/src/cmd/link/internal/ld/ld_test.go
@@ -13,6 +13,8 @@ import (
"testing"
)
+func init() { testenv.SetModVendor() }
+
func TestUndefinedRelocErrors(t *testing.T) {
t.Parallel()
testenv.MustHaveGoBuild(t)
diff --git a/src/cmd/link/link_test.go b/src/cmd/link/link_test.go
index 5200c3a6f084ca4f7a320eeb6ccb452db01de191..5043a778ca9edfcac8b3db1f0c8104a07a4265cb 100644
--- a/src/cmd/link/link_test.go
+++ b/src/cmd/link/link_test.go
@@ -38,6 +38,8 @@ func TestLargeSymName(t *testing.T) {
_ = AuthorPaidByTheColumnInch
}
+func init() { testenv.SetModVendor() }
+
func TestIssue21703(t *testing.T) {
t.Parallel()
diff --git a/src/cmd/nm/nm_test.go b/src/cmd/nm/nm_test.go
index 8176ddd7f458706065e33e910dd05860695f602a..82f4235510ecf251466f32c9deef30a0048ddd74 100644
--- a/src/cmd/nm/nm_test.go
+++ b/src/cmd/nm/nm_test.go
@@ -30,6 +30,8 @@ func testMain(m *testing.M) int {
return 0
}
+ testenv.SetModVendor()
+
tmpDir, err := ioutil.TempDir("", "TestNM")
if err != nil {
fmt.Println("TempDir failed:", err)
diff --git a/src/cmd/objdump/objdump_test.go b/src/cmd/objdump/objdump_test.go
index a2ca32960900ed8e86a0cf5292445600134ae539..7c874e853b92b459fce7d9247908f16e1099c50d 100644
--- a/src/cmd/objdump/objdump_test.go
+++ b/src/cmd/objdump/objdump_test.go
@@ -24,6 +24,8 @@ func TestMain(m *testing.M) {
if !testenv.HasGoBuild() {
return
}
+ testenv.SetModVendor()
+
var exitcode int
if err := buildObjdump(); err == nil {
exitcode = m.Run()
diff --git a/src/cmd/vet/all/main.go b/src/cmd/vet/all/main.go
index 2500c690bfd6ebf2ab9c20906f0c1ac8ae0aa292..8cc4140e6e6bf53db666cd99dc69a6a63a1b5087 100644
--- a/src/cmd/vet/all/main.go
+++ b/src/cmd/vet/all/main.go
@@ -44,6 +44,7 @@ func main() {
log.SetPrefix("vet/all: ")
log.SetFlags(0)
+ testenv.SetModVendor()
var err error
cmdGoPath, err = testenv.GoTool()
if err != nil {
diff --git a/src/cmd/vet/vet_test.go b/src/cmd/vet/vet_test.go
index 5d8139d977b81393c0d7d8db8e269ef219f27509..62c28fb9a21ccce7ab910b21a8db59bb5a0fed9b 100644
--- a/src/cmd/vet/vet_test.go
+++ b/src/cmd/vet/vet_test.go
@@ -32,6 +32,8 @@ func TestMain(m *testing.M) {
}
func testMain(m *testing.M) int {
+ testenv.SetModVendor()
+
dir, err := ioutil.TempDir("", "vet_test")
if err != nil {
fmt.Fprintln(os.Stderr, err)
diff --git a/src/crypto/x509/x509_test.go b/src/crypto/x509/x509_test.go
index f5851f1f11b79fe03dbb8e5e038e2a3fd6f05d83..fbcdb7b58e75afb71a6751848e48f8fcd047650c 100644
--- a/src/crypto/x509/x509_test.go
+++ b/src/crypto/x509/x509_test.go
@@ -1146,6 +1146,8 @@ func TestParsePEMCRL(t *testing.T) {
// Can't check the signature here without a package cycle.
}
+func init() { testenv.SetModVendor() }
+
func TestImports(t *testing.T) {
testenv.MustHaveGoRun(t)
diff --git a/src/debug/gosym/pclntab_test.go b/src/debug/gosym/pclntab_test.go
index d21f0e24a8324030d4297d3b7a6697807bb20468..c67fb66f0d843caf102ff6d35da996ffa6a66bce 100644
--- a/src/debug/gosym/pclntab_test.go
+++ b/src/debug/gosym/pclntab_test.go
@@ -21,6 +21,8 @@ var (
pclinetestBinary string
)
+func init() { testenv.SetModVendor() }
+
func dotest(t *testing.T) {
testenv.MustHaveGoBuild(t)
// For now, only works on amd64 platforms.
diff --git a/src/go/importer/importer_test.go b/src/go/importer/importer_test.go
index ff6e12c0da5233a5d340058e353a3768273a8722..2887ec6ea5b46b625ba166ff1b215ce31f22b32a 100644
--- a/src/go/importer/importer_test.go
+++ b/src/go/importer/importer_test.go
@@ -16,6 +16,8 @@ import (
"testing"
)
+func init() { testenv.SetModVendor() }
+
func TestForCompiler(t *testing.T) {
testenv.MustHaveGoBuild(t)
diff --git a/src/go/internal/srcimporter/srcimporter_test.go b/src/go/internal/srcimporter/srcimporter_test.go
index f8e1c323b32bb6adab817b1033a9712518a68613..06472447a635dc88f5fd83440e8761546dd5e2d3 100644
--- a/src/go/internal/srcimporter/srcimporter_test.go
+++ b/src/go/internal/srcimporter/srcimporter_test.go
@@ -10,7 +10,6 @@ import (
"go/types"
"internal/testenv"
"io/ioutil"
- "os"
"path"
"path/filepath"
"runtime"
@@ -19,22 +18,7 @@ import (
"time"
)
-func TestMain(m *testing.M) {
- // Add -mod=vendor to GOFLAGS to ensure that we don't fetch modules while importing std or cmd.
- //
- // TODO(golang.org/issue/30240): If we load go.mod files from vendor/
- // automatically, this will probably no longer be necessary.
- var goflags []string
- for _, f := range strings.Fields(os.Getenv("GOFLAGS")) {
- if !strings.HasPrefix(f, "-mod=") && !strings.HasPrefix(f, "--mod=") {
- goflags = append(goflags, f)
- }
- }
- goflags = append(goflags, "-mod=vendor")
- os.Setenv("GOFLAGS", strings.Join(goflags, " "))
-
- os.Exit(m.Run())
-}
+func init() { testenv.SetModVendor() }
const maxTime = 2 * time.Second
diff --git a/src/internal/testenv/testenv.go b/src/internal/testenv/testenv.go
index 8f69fe0da5fbda3180502907fab9f11c47f18e6f..72e4d803cb0ba9062da609e340e0ced5dc9260c3 100644
--- a/src/internal/testenv/testenv.go
+++ b/src/internal/testenv/testenv.go
@@ -19,6 +19,7 @@ import (
"runtime"
"strconv"
"strings"
+ "sync"
"testing"
)
@@ -77,6 +78,31 @@ func MustHaveGoRun(t testing.TB) {
}
}
+var modVendorOnce sync.Once
+
+// SetModVendor adds the "-mod=vendor" flag to the GOFLAGS environment variable.
+// This allows tests whose working directories are within the cmd and std
+// modules to run ``go'' commands without accessing the network to load
+// dependencies modules.
+//
+// SetModVendor must be called before any test may read the GOFLAGS environment
+// variable.
+//
+// TODO(golang.org/issue/30240): If we load go.mod files from vendor/
+// automatically, this will probably no longer be necessary.
+func SetModVendor() {
+ modVendorOnce.Do(func() {
+ var goflags []string
+ for _, f := range strings.Fields(os.Getenv("GOFLAGS")) {
+ if !strings.HasPrefix(f, "-mod=") && !strings.HasPrefix(f, "--mod=") {
+ goflags = append(goflags, f)
+ }
+ }
+ goflags = append(goflags, "-mod=vendor")
+ os.Setenv("GOFLAGS", strings.Join(goflags, " "))
+ })
+}
+
// GoToolPath reports the path to the Go tool.
// It is a convenience wrapper around GoTool.
// If the tool is unavailable GoToolPath calls t.Skip.
diff --git a/src/runtime/crash_test.go b/src/runtime/crash_test.go
index 03ebf022a6ef8d02aa94e4c9ff3be219f88090f5..3a27b269a126919c0b1cc719f84accb5c7bcad63 100644
--- a/src/runtime/crash_test.go
+++ b/src/runtime/crash_test.go
@@ -25,6 +25,8 @@ import (
var toRemove []string
func TestMain(m *testing.M) {
+ testenv.SetModVendor()
+
status := m.Run()
for _, file := range toRemove {
os.RemoveAll(file)
diff --git a/src/runtime/pprof/proto_test.go b/src/runtime/pprof/proto_test.go
index 4452d5123158e5c40af264536d92a21624000ddc..a276d81c491234f7b9ab95af1cbabe04bb3d5193 100644
--- a/src/runtime/pprof/proto_test.go
+++ b/src/runtime/pprof/proto_test.go
@@ -301,6 +301,8 @@ func TestProcSelfMaps(t *testing.T) {
})
}
+func init() { testenv.SetModVendor() }
+
// TestMapping checkes the mapping section of CPU profiles
// has the HasFunctions field set correctly. If all PCs included
// in the samples are successfully symbolized, the corresponding