[dev.typeparams] all: merge master (37f9a8f) into dev.typeparams

Conflicts:

- src/go/types/check_test.go

  CL 330629 fixed a bug in package qualification logic

- src/internal/buildcfg/exp.go

  CL 329930 make parseExperiments get go arch string as input param

Merge List:

+ 2021-06-25 37f9a8f69d go/types: fix a bug in package qualification logic
+ 2021-06-24 c309c89db5 reflect: document that InterfaceData is a low-entropy RNG
+ 2021-06-24 cce621431a cmd/compile: fix wrong type in SSA generation for OSLICE2ARRPTR
+ 2021-06-24 600a2a4ffb cmd/go: don't try to add replaced versions that won't be selected
+ 2021-06-24 a9bb38222a net: remove hard-coded timeout in dialClosedPort test helper
+ 2021-06-24 86d72fa2cb time: handle invalid UTF-8 byte sequences in quote to prevent panic
+ 2021-06-24 44a12e5f33 cmd/go: search breadth-first instead of depth-first for test dependency cycles
+ 2021-06-24 73496e0df0 net: use absDomainName in the Windows lookupPTR test helper
+ 2021-06-24 222ed1b38a os: enable TestFifoEOF on openbsd
+ 2021-06-22 0ebd5a8de0 cmd/go: update ToolTags based on GOARCH value
+ 2021-06-22 5bd09e5efc spec: unsafe.Add/Slice are not permitted in statement context
+ 2021-06-22 666315b4d3 runtime/internal/atomic: remove incorrect pointer indirection in comment
+ 2021-06-22 63daa774b5 go/types: guard against checking instantiation when generics is disabled
+ 2021-06-22 197a5ee2ab cmd/gofmt: remove stale documentation for the -G flag
+ 2021-06-22 9afd158eb2 go/parser: parse an ast.IndexExpr for a[]
+ 2021-06-21 1bd5a20e3c cmd/go: add a -go flag to 'go mod graph'
+ 2021-06-21 761edf71f6 cmd/internal/moddeps: use a temporary directory for GOMODCACHE if needed
+ 2021-06-21 a0400420ad cmd/internal/moddeps: use -mod=readonly instead of -mod=mod
+ 2021-06-21 3f9ec83b10 cmd/go: document GOPPC64 environment variable
+ 2021-06-21 20bdfba325 go/scanner: fall back to next() when encountering 0 bytes in parseIdentifier
+ 2021-06-21 44f9a3566c database/sql: fix deadlock test in prepare statement

Change-Id: I16490e8ea70ee65081f467223857033842da513a

1 files changed, 32 insertions, 3 deletions

diff --git a/src/cmd/internal/moddeps/moddeps_test.go b/src/cmd/internal/moddeps/moddeps_test.go
index 7723250468..56c3b2585c 100644
--- a/src/cmd/internal/moddeps/moddeps_test.go
+++ b/src/cmd/internal/moddeps/moddeps_test.go
@@ -5,6 +5,7 @@
 package moddeps_test
 
 import (
+	"bytes"
 	"encoding/json"
 	"fmt"
 	"internal/testenv"
@@ -68,7 +69,7 @@ func TestAllDependencies(t *testing.T) {
 
 			// There is no vendor directory, so the module must have no dependencies.
 			// Check that the list of active modules contains only the main module.
-			cmd := exec.Command(goBin, "list", "-mod=mod", "-m", "all")
+			cmd := exec.Command(goBin, "list", "-mod=readonly", "-m", "all")
 			cmd.Env = append(os.Environ(), "GO111MODULE=on")
 			cmd.Dir = m.Dir
 			cmd.Stderr = new(strings.Builder)
@@ -123,10 +124,38 @@ func TestAllDependencies(t *testing.T) {
 		t.Skip("skipping because a diff command with support for --recursive and --unified flags is unavailable")
 	}
 
+	// We're going to check the standard modules for tidiness, so we need a usable
+	// GOMODCACHE. If the default directory doesn't exist, use a temporary
+	// directory instead. (That can occur, for example, when running under
+	// run.bash with GO_TEST_SHORT=0: run.bash sets GOPATH=/nonexist-gopath, and
+	// GO_TEST_SHORT=0 causes it to run this portion of the test.)
+	var modcacheEnv []string
+	{
+		out, err := exec.Command(goBin, "env", "GOMODCACHE").Output()
+		if err != nil {
+			t.Fatalf("%s env GOMODCACHE: %v", goBin, err)
+		}
+		modcacheOk := false
+		if gomodcache := string(bytes.TrimSpace(out)); gomodcache != "" {
+			if _, err := os.Stat(gomodcache); err == nil {
+				modcacheOk = true
+			}
+		}
+		if !modcacheOk {
+			modcacheEnv = []string{
+				"GOMODCACHE=" + t.TempDir(),
+				"GOFLAGS=" + os.Getenv("GOFLAGS") + " -modcacherw", // Allow t.TempDir() to clean up subdirectories.
+			}
+		}
+	}
+
 	// Build the bundle binary at the golang.org/x/tools
 	// module version specified in GOROOT/src/cmd/go.mod.
 	bundleDir := t.TempDir()
-	r := runner{Dir: filepath.Join(runtime.GOROOT(), "src/cmd")}
+	r := runner{
+		Dir: filepath.Join(runtime.GOROOT(), "src/cmd"),
+		Env: append(os.Environ(), modcacheEnv...),
+	}
 	r.run(t, goBin, "build", "-mod=readonly", "-o", bundleDir, "golang.org/x/tools/cmd/bundle")
 
 	var gorootCopyDir string
@@ -160,7 +189,7 @@ func TestAllDependencies(t *testing.T) {
 			}
 			r := runner{
 				Dir: filepath.Join(gorootCopyDir, rel),
-				Env: append(os.Environ(),
+				Env: append(append(os.Environ(), modcacheEnv...),
 					// Set GOROOT.
 					"GOROOT="+gorootCopyDir,
 					// Explicitly override PWD and clear GOROOT_FINAL so that GOROOT=gorootCopyDir is definitely used.