fix(mempkg): don't attempt to validate name of an empty package

gno.land/cmd/gnoland/start.go

@@ -235,6 +235,7 @@ func makeGenesisDoc(
 	for _, pkg := range nonDraftPkgs {
 		// open files in directory as MemPackage.
 		memPkg := gno.ReadMemPackage(pkg.Dir, pkg.Name)
+
 		var tx std.Tx
 		tx.Msgs = []std.Msg{
 			vmm.MsgAddPackage{

gno.land/pkg/sdk/vm/builtins.go

@@ -25,6 +25,11 @@ func (vm *VMKeeper) initBuiltinPackagesAndTypes(store gno.Store) {
 			return nil, nil
 		}
 		memPkg := gno.ReadMemPackage(stdlibPath, pkgPath)
+		if memPkg.IsEmpty() {
+			// no gno files are present, skip this package
+			return nil, nil
+		}
+
 		m2 := gno.NewMachineWithOptions(gno.MachineOptions{
 			PkgPath: "gno.land/r/stdlibs/" + pkgPath,
 			// PkgPath: pkgPath,

gnovm/pkg/gnolang/nodes.go

@@ -1132,8 +1132,13 @@ func ReadMemPackage(dir string, pkgPath string) *std.MemPackage {
 				Body: string(bz),
 			})
 	}
-	validatePkgName(string(pkgName))
-	memPkg.Name = string(pkgName)
+
+	// If no .gno files are present, package simply does not exist.
+	if !memPkg.IsEmpty() {
+		validatePkgName(string(pkgName))
+		memPkg.Name = string(pkgName)
+	}
+
 	return memPkg
 }
 

gnovm/tests/imports.go

@@ -97,15 +97,20 @@ func TestStore(rootDir, filesPath string, stdin io.Reader, stdout, stderr io.Wri
 			stdlibPath := filepath.Join(rootDir, "gnovm", "stdlibs", pkgPath)
 			if osm.DirExists(stdlibPath) {
 				memPkg := gno.ReadMemPackage(stdlibPath, pkgPath)
-				m2 := gno.NewMachineWithOptions(gno.MachineOptions{
-					// NOTE: see also pkgs/sdk/vm/builtins.go
-					// XXX: why does this fail when just pkgPath?
-					PkgPath: "gno.land/r/stdlibs/" + pkgPath,
-					Output:  stdout,
-					Store:   store,
-				})
-				save := pkgPath != "testing" // never save the "testing" package
-				return m2.RunMemPackage(memPkg, save)
+				if !memPkg.IsEmpty() {
+					m2 := gno.NewMachineWithOptions(gno.MachineOptions{
+						// NOTE: see also pkgs/sdk/vm/builtins.go
+						// XXX: why does this fail when just pkgPath?
+						PkgPath: "gno.land/r/stdlibs/" + pkgPath,
+						Output:  stdout,
+						Store:   store,
+					})
+					save := pkgPath != "testing" // never save the "testing" package
+					return m2.RunMemPackage(memPkg, save)
+				}
+
+				// There is no package there, but maybe we have a
+				// native counterpart below.
 			}
 		}
 
@@ -413,6 +418,10 @@ func TestStore(rootDir, filesPath string, stdin io.Reader, stdout, stderr io.Wri
 			stdlibPath := filepath.Join(rootDir, "gnovm", "stdlibs", pkgPath)
 			if osm.DirExists(stdlibPath) {
 				memPkg := gno.ReadMemPackage(stdlibPath, pkgPath)
+				if memPkg.IsEmpty() {
+					panic(fmt.Sprintf("found an empty package %q", pkgPath))
+				}
+
 				m2 := gno.NewMachineWithOptions(gno.MachineOptions{
 					PkgPath: "test",
 					Output:  stdout,
@@ -427,6 +436,10 @@ func TestStore(rootDir, filesPath string, stdin io.Reader, stdout, stderr io.Wri
 		examplePath := filepath.Join(rootDir, "examples", pkgPath)
 		if osm.DirExists(examplePath) {
 			memPkg := gno.ReadMemPackage(examplePath, pkgPath)
+			if memPkg.IsEmpty() {
+				panic(fmt.Sprintf("found an empty package %q", pkgPath))
+			}
+
 			m2 := gno.NewMachineWithOptions(gno.MachineOptions{
 				PkgPath: "test",
 				Output:  stdout,

gnovm/tests/package_test.go

@@ -14,6 +14,7 @@ import (
 	// "go/build"
 
 	gno "github.com/gnolang/gno/gnovm/pkg/gnolang"
+	"github.com/jaekwon/testify/require"
 )
 
 func TestPackages(t *testing.T) {
@@ -60,6 +61,7 @@ func runPackageTest(t *testing.T, dir string, path string) {
 	t.Helper()
 
 	memPkg := gno.ReadMemPackage(dir, path)
+	require.False(t, memPkg.IsEmpty())
 
 	stdin := new(bytes.Buffer)
 	// stdout := new(bytes.Buffer)

tm2/pkg/crypto/keys/client/addpkg.go

@@ -98,6 +98,9 @@ func execAddPkg(cfg *addPkgCfg, args []string, io *commands.IO) error {
 
 	// open files in directory as MemPackage.
 	memPkg := gno.ReadMemPackage(cfg.pkgDir, cfg.pkgPath)
+	if memPkg.IsEmpty() {
+		panic(fmt.Sprintf("found an empty package %q", cfg.pkgPath))
+	}
 
 	// precompile and validate syntax
 	err = gno.PrecompileAndCheckMempkg(memPkg)

tm2/pkg/std/memfile.go

@@ -30,6 +30,10 @@ func (mempkg *MemPackage) GetFile(name string) *MemFile {
 	return nil
 }
 
+func (mempkg *MemPackage) IsEmpty() bool {
+	return len(mempkg.Files) == 0
+}
+
 const (
 	reDomainPart   = `gno\.land`
 	rePathPart     = `[a-z][a-z0-9_]*`