feat: gno mod graph (#3588)

Basic initial version compatible with `go mod graph` in terms of output,
while allowing the specification of folders through an optional
argument.

- [x] implement
- [x] tests
- [x] share examples

Depends on #3587

---------

Signed-off-by: moul <94029+moul@users.noreply.github.com>

gnovm/cmd/gno/mod.go

@@ -34,7 +34,7 @@ func newModCmd(io commands.IO) *commands.Command {
 	cmd.AddSubCommands(
 		newModDownloadCmd(io),
 		// edit
-		// graph
+		newModGraphCmd(io),
 		newModInitCmd(),
 		newModTidy(io),
 		// vendor
@@ -61,6 +61,21 @@ func newModDownloadCmd(io commands.IO) *commands.Command {
 	)
 }
 
+func newModGraphCmd(io commands.IO) *commands.Command {
+	cfg := &modGraphCfg{}
+	return commands.NewCommand(
+		commands.Metadata{
+			Name:       "graph",
+			ShortUsage: "graph [path]",
+			ShortHelp:  "print module requirement graph",
+		},
+		cfg,
+		func(_ context.Context, args []string) error {
+			return execModGraph(cfg, args, io)
+		},
+	)
+}
+
 func newModInitCmd() *commands.Command {
 	return commands.NewCommand(
 		commands.Metadata{
@@ -144,6 +159,38 @@ func (c *modDownloadCfg) RegisterFlags(fs *flag.FlagSet) {
 	)
 }
 
+type modGraphCfg struct{}
+
+func (c *modGraphCfg) RegisterFlags(fs *flag.FlagSet) {
+	// /out std
+	// /out remote
+	// /out _test processing
+	// ...
+}
+
+func execModGraph(cfg *modGraphCfg, args []string, io commands.IO) error {
+	// default to current directory if no args provided
+	if len(args) == 0 {
+		args = []string{"."}
+	}
+	if len(args) > 1 {
+		return flag.ErrHelp
+	}
+
+	stdout := io.Out()
+
+	pkgs, err := gnomod.ListPkgs(args[0])
+	if err != nil {
+		return err
+	}
+	for _, pkg := range pkgs {
+		for _, dep := range pkg.Imports {
+			fmt.Fprintf(stdout, "%s %s\n", pkg.Name, dep)
+		}
+	}
+	return nil
+}
+
 func execModDownload(cfg *modDownloadCfg, args []string, io commands.IO) error {
 	if len(args) > 0 {
 		return flag.ErrHelp

gnovm/cmd/gno/mod_test.go

@@ -210,6 +210,34 @@ func TestModApp(t *testing.T) {
 
 # gno.land/p/demo/avl
 valid.gno
+`,
+		},
+
+		// test `gno mod graph`
+		{
+			args:                 []string{"mod", "graph"},
+			testDir:              "../../tests/integ/minimalist_gnomod",
+			simulateExternalRepo: true,
+			stdoutShouldBe:       ``,
+		},
+		{
+			args:                 []string{"mod", "graph"},
+			testDir:              "../../tests/integ/valid1",
+			simulateExternalRepo: true,
+			stdoutShouldBe:       ``,
+		},
+		{
+			args:                 []string{"mod", "graph"},
+			testDir:              "../../tests/integ/valid2",
+			simulateExternalRepo: true,
+			stdoutShouldBe: `gno.land/p/integ/valid gno.land/p/demo/avl
+`,
+		},
+		{
+			args:                 []string{"mod", "graph"},
+			testDir:              "../../tests/integ/require_remote_module",
+			simulateExternalRepo: true,
+			stdoutShouldBe: `gno.land/tests/importavl gno.land/p/demo/avl
 `,
 		},
 	}