cue/load: assume that Config.Registry is set when SkipImports is false

Now that the new modules implementation is always on by default,
any function which is only called when Config.SkipImports is false,
such as loadPackages or absDirFromImportPath1, can assume that
Config.Registry is set. Even if the user leaves it as nil, it takes
a default value derived from Config.Env.

Signed-off-by: Daniel Martí <[email protected]>
Change-Id: I93b85fd9fa9cdad5e6d92d0cf8244490a1bb6679
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1205859
Reviewed-by: Roger Peppe <[email protected]>
TryBot-Result: CUEcueckoo <[email protected]>

Author: mvdan

cue/load/import.go

@@ -429,68 +429,48 @@ func (l *loader) absDirFromImportPath1(pos token.Pos, p importPath) (absDir stri
 	if isStdlibPackage(string(p)) {
 		return "", "", fmt.Errorf("standard library import path %q cannot be imported as a CUE package", p)
 	}
+	if l.pkgs == nil {
+		return "", "", fmt.Errorf("imports are unavailable because there is no cue.mod/module.cue file")
+	}
 	// Extract the package name.
 	parts := module.ParseImportPath(string(p))
 	unqualified := parts.Unqualified().String()
-	if l.cfg.Registry != nil {
-		if l.pkgs == nil {
-			return "", "", fmt.Errorf("imports are unavailable because there is no cue.mod/module.cue file")
-		}
-		// TODO predicate registry-aware lookup on module.cue-declared CUE version?
-
-		// Note: use the canonical form of the import path because
-		// that's the form passed to [modpkgload.LoadPackages]
-		// and hence it's available by that name via Pkg.
-		pkg := l.pkgs.Pkg(parts.Canonical().String())
-		// TODO(mvdan): using "unqualified" for the errors below doesn't seem right,
-		// should we not be using either the original path or the canonical path?
-		// The unqualified import path should only be used for filepath.FromSlash further below.
-		if pkg == nil {
-			return "", "", fmt.Errorf("no dependency found for package %q", unqualified)
+	// TODO predicate registry-aware lookup on module.cue-declared CUE version?
+
+	// Note: use the canonical form of the import path because
+	// that's the form passed to [modpkgload.LoadPackages]
+	// and hence it's available by that name via Pkg.
+	pkg := l.pkgs.Pkg(parts.Canonical().String())
+	// TODO(mvdan): using "unqualified" for the errors below doesn't seem right,
+	// should we not be using either the original path or the canonical path?
+	// The unqualified import path should only be used for filepath.FromSlash further below.
+	if pkg == nil {
+		return "", "", fmt.Errorf("no dependency found for package %q", unqualified)
+	}
+	if err := pkg.Error(); err != nil {
+		return "", "", fmt.Errorf("cannot find package %q: %v", unqualified, err)
+	}
+	if mv := pkg.Mod(); mv.IsLocal() {
+		// It's a local package that's present inside one or both of the gen, usr or pkg
+		// directories. Even though modpkgload tells us exactly what those directories
+		// are, the rest of the cue/load logic expects only a single directory for now,
+		// so just use that.
+		absDir = filepath.Join(GenPath(l.cfg.ModuleRoot), parts.Path)
+	} else {
+		locs := pkg.Locations()
+		if len(locs) > 1 {
+			return "", "", fmt.Errorf("package %q unexpectedly found in multiple locations", unqualified)
 		}
-		if err := pkg.Error(); err != nil {
-			return "", "", fmt.Errorf("cannot find package %q: %v", unqualified, err)
+		if len(locs) == 0 {
+			return "", "", fmt.Errorf("no location found for package %q", unqualified)
 		}
-		if mv := pkg.Mod(); mv.IsLocal() {
-			// It's a local package that's present inside one or both of the gen, usr or pkg
-			// directories. Even though modpkgload tells us exactly what those directories
-			// are, the rest of the cue/load logic expects only a single directory for now,
-			// so just use that.
-			absDir = filepath.Join(GenPath(l.cfg.ModuleRoot), parts.Path)
-		} else {
-			locs := pkg.Locations()
-			if len(locs) > 1 {
-				return "", "", fmt.Errorf("package %q unexpectedly found in multiple locations", unqualified)
-			}
-			if len(locs) == 0 {
-				return "", "", fmt.Errorf("no location found for package %q", unqualified)
-			}
-			var err error
-			absDir, err = absPathForSourceLoc(locs[0])
-			if err != nil {
-				return "", "", fmt.Errorf("cannot determine source directory for package %q: %v", unqualified, err)
-			}
+		var err error
+		absDir, err = absPathForSourceLoc(locs[0])
+		if err != nil {
+			return "", "", fmt.Errorf("cannot determine source directory for package %q: %v", unqualified, err)
 		}
-		return absDir, pkg.Mod().Path(), nil
-	}
-
-	// Determine the directory without using the registry.
-
-	sub := filepath.FromSlash(unqualified)
-	switch hasPrefix := strings.HasPrefix(unqualified, l.cfg.Module); {
-	case hasPrefix && len(sub) == len(l.cfg.Module):
-		modPath = l.cfg.Module
-		absDir = l.cfg.ModuleRoot
-
-	case hasPrefix && unqualified[len(l.cfg.Module)] == '/':
-		modPath = l.cfg.Module
-		absDir = filepath.Join(l.cfg.ModuleRoot, sub[len(l.cfg.Module)+1:])
-
-	default:
-		modPath = "local"
-		absDir = filepath.Join(GenPath(l.cfg.ModuleRoot), sub)
 	}
-	return absDir, modPath, err
+	return absDir, pkg.Mod().Path(), nil
 }
 
 func absPathForSourceLoc(loc module.SourceLoc) (string, error) {

cue/load/instances.go

@@ -173,7 +173,7 @@ func loadPackages(
 	otherFiles []*build.File,
 	tg *tagger,
 ) (*modpkgload.Packages, error) {
-	if cfg.Registry == nil || cfg.modFile == nil || cfg.modFile.Module == "" {
+	if cfg.modFile == nil || cfg.modFile.Module == "" {
 		return nil, nil
 	}
 	mainModPath := cfg.modFile.QualifiedModule()