fix support with the latest Go master version

It added packages which are only built with the boringcrypto build tag,
so trying to `go list` them will fail even though it doesn't matter.

While here, a few more minor cleanups:

1) Hide GarbleActionID and ToObfuscate from encoding/json, so that they
   can't possibly collide with the fields consumed from `go list -json`.

2) Add test cases for `garble build` with packages that fail to load.
   Note that this requires GOGARBLE=* to avoid its "does not match any
   package to be built" error.

3) Remove the last use of interface{}, in a testdata file.

Fixes #531.

.github/workflows/test.yml

@@ -71,8 +71,7 @@ jobs:
     steps:
     - name: Install Go
       env:
-        # Note that newer tip versions from May break due to the boringtls merge.
-        GO_COMMIT: e6dfdbd11d5dcc9f918150552f50ca6cd524b89b # 2022-04-23
+        GO_COMMIT: 016d7552138077741a9c3fdadc73c0179f5d3ff7 # 2022-05-12
       run: |
         cd $HOME
         mkdir $HOME/gotip

shared.go

@@ -139,9 +139,10 @@ type listedPackage struct {
 	ImportMap  map[string]string
 	Standard   bool
 
-	Dir     string
-	GoFiles []string
-	Imports []string
+	Dir        string
+	GoFiles    []string
+	Imports    []string
+	Incomplete bool
 
 	// The fields below are not part of 'go list', but are still reused
 	// between garble processes. Use "Garble" as a prefix to ensure no
@@ -149,10 +150,10 @@ type listedPackage struct {
 
 	// TODO(mvdan): consider filling this iff ToObfuscate==true,
 	// which will help ensure we don't obfuscate any of their names otherwise.
-	GarbleActionID []byte
+	GarbleActionID []byte `json:"-"`
 
 	// ToObfuscate records whether the package should be obfuscated.
-	ToObfuscate bool
+	ToObfuscate bool `json:"-"`
 }
 
 func (p *listedPackage) obfuscatedImportPath() string {
@@ -176,7 +177,7 @@ func appendListedPackages(packages []string, withDeps bool) error {
 	// TODO: perhaps include all top-level build flags set by garble,
 	// including -buildvcs=false.
 	// They shouldn't affect "go list" here, but might as well be consistent.
-	args := []string{"list", "-json", "-export", "-trimpath"}
+	args := []string{"list", "-json", "-export", "-trimpath", "-e"}
 	if withDeps {
 		args = append(args, "-deps")
 	}
@@ -209,6 +210,13 @@ func appendListedPackages(packages []string, withDeps bool) error {
 		if err := dec.Decode(&pkg); err != nil {
 			return err
 		}
+
+		// Note that we use the `-e` flag above with `go list`.
+		// If a package fails to load, the Incomplete and Error fields will be set.
+		// We still record failed packages in the ListedPackages map,
+		// because some like crypto/internal/boring/fipstls simply fall under
+		// "build constraints exclude all Go files" and can be ignored.
+		// Real build errors will still be surfaced by `go build -toolexec` later.
 		if cache.ListedPackages[pkg.ImportPath] != nil {
 			return fmt.Errorf("duplicate package: %q", pkg.ImportPath)
 		}
@@ -235,6 +243,9 @@ func appendListedPackages(packages []string, withDeps bool) error {
 		case cannotObfuscate[path], runtimeAndDeps[path]:
 			// We don't support obfuscating these yet.
 
+		case pkg.Incomplete:
+			// We can't obfuscate packages which weren't loaded.
+
 		case pkg.Name == "main" && strings.HasSuffix(path, ".test"),
 			path == "command-line-arguments",
 			strings.HasPrefix(path, "plugin/unnamed"),
@@ -335,6 +346,8 @@ func listPackage(path string) (*listedPackage, error) {
 		startTime := time.Now()
 		// Obtained via scripts/runtime-linknamed-nodeps.sh as of Go 1.18beta1.
 		runtimeLinknamed := []string{
+			"crypto/internal/boring",
+			"crypto/internal/boring/fipstls",
 			"crypto/x509/internal/macos",
 			"internal/poll",
 			"internal/reflectlite",

testdata/scripts/help.txt

@@ -1,3 +1,5 @@
+env GOGARBLE=*
+
 ! garble
 stderr 'Garble obfuscates Go code'
 stderr 'garble \[garble flags\] command'
@@ -77,6 +79,14 @@ stderr 'must precede command, like: garble -seed=random build \./pkg'
 [windows] ! garble C:\does\not\exist\compile
 stderr 'run "garble \[command\]"'
 
+! garble build badpackage
+stderr 'package badpackage is not in GOROOT'
+! stdout .
+
+! garble build ./badpackage
+stderr 'directory not found'
+! stdout .
+
 # Test the version command. Note that test binaries exclude VCS build info,
 # and we reuse the test binary for garble itself, so that's missing.
 # To avoid building another garble binary,

testdata/scripts/reflect.txt

@@ -229,7 +229,7 @@ type ReflectEmbeddedAlias = ReflectEmbeddingNamed
 
 type ReflectEmbeddingNamed struct{}
 
-func VariadicReflect(x interface{}, ys ...interface{}) int {
+func VariadicReflect(x any, ys ...any) int {
 	_ = reflect.TypeOf(x)
 	_ = reflect.TypeOf(ys)