cue/load: clean up some var names and code organization

This CL:

- improves naming of a few methods
- removes an unnecessary method
- moves some var declarations closer to their usage

Signed-off-by: Noam Dolovich <noam.tzvi.dolovich@gmail.com>
Change-Id: Ia94b73088355565a94461db95806232eb7842fa3
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1193882
TryBot-Result: CUEcueckoo <cueckoo@cuelang.org>
Unity-Result: CUE porcuepine <cue.porcuepine@gmail.com>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>

cue/load/config.go

@@ -371,7 +371,7 @@ func (c Config) complete() (cfg *Config, err error) {
 	if c.ModuleRoot == "" {
 		// Only consider the current directory by default
 		c.ModuleRoot = c.Dir
-		if root := c.findRoot(c.Dir); root != "" {
+		if root := c.findModRoot(c.Dir); root != "" {
 			c.ModuleRoot = root
 		}
 	} else if !filepath.IsAbs(c.ModuleRoot) {
@@ -442,19 +442,18 @@ func (c *Config) loadModule() error {
 	return nil
 }
 
-func (c Config) isRoot(dir string) bool {
-	fs := &c.fileSystem
+func (c Config) isModRoot(dir string) bool {
 	// Note: cue.mod used to be a file. We still allow both to match.
-	_, err := fs.stat(filepath.Join(dir, modDir))
+	_, err := c.fileSystem.stat(filepath.Join(dir, modDir))
 	return err == nil
 }
 
-// findRoot returns the module root that's ancestor
+// findModRoot returns the module root that's ancestor
 // of the given absolute directory path, or "" if none was found.
-func (c Config) findRoot(absDir string) string {
+func (c Config) findModRoot(absDir string) string {
 	abs := absDir
 	for {
-		if c.isRoot(abs) {
+		if c.isModRoot(abs) {
 			return abs
 		}
 		d := filepath.Dir(abs)

cue/load/fs.go

@@ -134,10 +134,6 @@ func (fs *fileSystem) init(cwd string, overlay map[string]Source) error {
 	return nil
 }
 
-func (fs *fileSystem) joinPath(elem ...string) string {
-	return filepath.Join(elem...)
-}
-
 func (fs *fileSystem) makeAbs(path string) string {
 	if filepath.IsAbs(path) {
 		return path
@@ -270,7 +266,7 @@ func (fs *fileSystem) walkRec(path string, entry iofs.DirEntry, f walkFunc) erro
 	}
 
 	for _, entry := range dir {
-		filename := fs.joinPath(path, entry.Name())
+		filename := filepath.Join(path, entry.Name())
 		err = fs.walkRec(filename, entry, f)
 		if err != nil {
 			if !entry.IsDir() || err != skipDir {
@@ -335,7 +331,7 @@ func (fs *ioFS) ReadDir(name string) ([]iofs.DirEntry, error) {
 	return fs.fs.readDir(fpath)
 }
 
-// ReadDir implements [io/fs.ReadFileFS].
+// ReadFile implements [io/fs.ReadFileFS].
 func (fs *ioFS) ReadFile(name string) ([]byte, error) {
 	fpath, err := fs.absPathFromFSPath(name)
 	if err != nil {

cue/load/import.go

@@ -131,7 +131,7 @@ func (l *loader) importPkg(pos token.Pos, p *build.Instance) []*build.Instance {
 	// have the same module scope and that there are no invalid modules.
 	inModule := false // if pkg == "_"
 	for _, d := range dirs {
-		if l.cfg.findRoot(d[1]) != "" {
+		if l.cfg.findModRoot(d[1]) != "" {
 			inModule = true
 			break
 		}
@@ -156,7 +156,7 @@ func (l *loader) importPkg(pos token.Pos, p *build.Instance) []*build.Instance {
 				fp.add(dir, &bf, importComment)
 			}
 
-			if p.PkgName == "" || !inModule || l.cfg.isRoot(dir) || dir == d[0] {
+			if p.PkgName == "" || !inModule || l.cfg.isModRoot(dir) || dir == d[0] {
 				break
 			}
 
@@ -259,23 +259,20 @@ func (l *loader) newRelInstance(pos token.Pos, path, pkgName string) *build.Inst
 		panic(fmt.Errorf("non-relative import path %q passed to newRelInstance", path))
 	}
 
-	var err errors.Error
-	dir := path
-
 	p := l.cfg.Context.NewInstance(path, l.loadFunc)
 	p.PkgName = pkgName
 	p.DisplayPath = filepath.ToSlash(path)
 	// p.ImportPath = string(dir) // compute unique ID.
 	p.Root = l.cfg.ModuleRoot
 	p.Module = l.cfg.Module
 
-	dir = filepath.Join(l.cfg.Dir, filepath.FromSlash(path))
-
+	var err errors.Error
 	if path != cleanImport(path) {
 		err = errors.Append(err, l.errPkgf(nil,
 			"non-canonical import path: %q should be %q", path, pathpkg.Clean(path)))
 	}
 
+	dir := filepath.Join(l.cfg.Dir, filepath.FromSlash(path))
 	if importPath, e := l.importPathFromAbsDir(fsPath(dir), path); e != nil {
 		// Detect later to keep error messages consistent.
 	} else {