fix(cmd/gno): support new examples gno.mods (#915)

gnovm/cmd/gno/doc.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"flag"
 	"fmt"
+	"io/fs"
 	"os"
 	"path/filepath"
 
@@ -84,14 +85,25 @@ func execDoc(cfg *docCfg, args []string, io *commands.IO) error {
 		return fmt.Errorf("could not determine working directory: %w", err)
 	}
 
+	var modDirs []string
+
 	rd, err := gnomod.FindRootDir(wd)
 	if err != nil && !errors.Is(err, gnomod.ErrGnoModNotFound) {
 		return fmt.Errorf("error determining root gno.mod file: %w", err)
 	}
-	modDirs := []string{rd}
+	if !errors.Is(err, gnomod.ErrGnoModNotFound) {
+		modDirs = append(modDirs, rd)
+	}
+
+	examplesModules, err := findGnomodExamples(filepath.Join(cfg.rootDir, "examples"))
+	if err != nil {
+		io.Printfln("warning: error scanning examples directory for modules: %v", err)
+	} else {
+		modDirs = append(modDirs, examplesModules...)
+	}
 
 	// select dirs from which to gather directories
-	dirs := []string{filepath.Join(cfg.rootDir, "gnovm/stdlibs"), filepath.Join(cfg.rootDir, "examples")}
+	dirs := []string{filepath.Join(cfg.rootDir, "gnovm/stdlibs")}
 	res, err := doc.ResolveDocumentable(dirs, modDirs, args, cfg.unexported)
 	if res == nil {
 		return err
@@ -109,3 +121,17 @@ func execDoc(cfg *docCfg, args []string, io *commands.IO) error {
 		},
 	)
 }
+
+func findGnomodExamples(dir string) ([]string, error) {
+	dirs := make([]string, 0, 64) // "hint" about the size
+	err := filepath.WalkDir(dir, func(path string, e fs.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		if !e.IsDir() && e.Name() == "gno.mod" {
+			dirs = append(dirs, filepath.Dir(path))
+		}
+		return nil
+	})
+	return dirs, err
+}

gnovm/pkg/doc/dirs.go

@@ -34,7 +34,8 @@ type bfsDirs struct {
 }
 
 // newDirs begins scanning the given stdlibs directory.
-// dirs are "gopath-like" directories, such as @/gnovm/stdlibs and @/examples.
+// dirs are "gopath-like" directories, such as @/gnovm/stdlibs, whose path
+// relative to the root specify the import path.
 // modDirs are user directories, expected to have gno.mod files
 func newDirs(dirs []string, modDirs []string) *bfsDirs {
 	d := &bfsDirs{
@@ -99,6 +100,14 @@ func getGnoModDirs(gm *gnomod.File) []bfsDir {
 	for _, r := range gm.Require {
 		mv := gm.Resolve(r)
 		path := gnomod.PackageDir("", mv)
+		if _, err := os.Stat(path); err != nil {
+			// only give directories which actually exist and don't give
+			// an error when accessing
+			if !os.IsNotExist(err) {
+				log.Println("open source directories from gno.mod:", err)
+			}
+			continue
+		}
 		dirs = append(dirs, bfsDir{
 			importPath: mv.Path,
 			dir:        path,

gnovm/pkg/doc/doc.go

@@ -206,7 +206,7 @@ func resolveDocumentable(dirs *bfsDirs, parsed docArgs, unexported bool) (Docume
 		parsed = docArgs{pkg: ".", sym: parsed.pkg, acc: parsed.sym}
 		return resolveDocumentable(dirs, parsed, unexported)
 	}
-	// we wanted documentabfsDirn about a package, and we found one!
+	// we wanted documentation about a package, and we found one!
 	if parsed.sym == "" {
 		return &documentable{bfsDir: candidates[0]}, nil
 	}