Support replacing module with different version

pkgs/gnolang/gnomod/gnomod.go

@@ -106,6 +106,18 @@ func GnoToGoMod(f File) (*File, error) {
 		})
 	}
 
+	// Since we already fetched and replaced replacement modules
+	// with `/pkg/gnomod/...` path.
+	// Ignore leftovers.
+	var repl []*modfile.Replace
+	for _, r := range f.Replace {
+		if !modfile.IsDirectoryPath(r.New.Path) {
+			continue
+		}
+		repl = append(repl, r)
+	}
+	f.Replace = repl
+
 	return &f, nil
 }
 

pkgs/gnolang/gnomod/parse.go

@@ -2,7 +2,6 @@ package gnomod
 
 import (
 	"fmt"
-	"path/filepath"
 	"reflect"
 	"strings"
 
@@ -143,42 +142,3 @@ func (f *File) add(errs *modfile.ErrorList, block *modfile.LineBlock, line *modf
 		f.Replace = append(f.Replace, replace)
 	}
 }
-
-func parseReplace(filename string, line *modfile.Line, verb string, args []string) (*modfile.Replace, *modfile.Error) {
-	wrapError := func(err error) *modfile.Error {
-		return &modfile.Error{
-			Filename: filename,
-			Pos:      line.Start,
-			Err:      err,
-		}
-	}
-	errorf := func(format string, args ...interface{}) *modfile.Error {
-		return wrapError(fmt.Errorf(format, args...))
-	}
-
-	if len(args) != 3 || args[1] != "=>" {
-		return nil, errorf("usage: %s module/path => ../local/directory", verb)
-	}
-	s, err := parseString(&args[0])
-	if err != nil {
-		return nil, errorf("invalid quoted string: %v", err)
-	}
-
-	ns, err := parseString(&args[2])
-	if err != nil {
-		return nil, errorf("invalid quoted string: %v", err)
-	}
-
-	if !modfile.IsDirectoryPath(ns) {
-		return nil, errorf("replacement module must be directory path (rooted or starting with ./ or ../)")
-	}
-	if filepath.Separator == '/' && strings.Contains(ns, `\`) {
-		return nil, errorf("replacement directory appears to be Windows path (on a non-windows system)")
-	}
-
-	return &modfile.Replace{
-		Old:    module.Version{Path: s, Version: "v0.0.0"},
-		New:    module.Version{Path: ns},
-		Syntax: line,
-	}, nil
-}

pkgs/gnolang/gnomod/read.go

@@ -14,6 +14,7 @@ import (
 	"errors"
 	"fmt"
 	"os"
+	"path/filepath"
 	"strconv"
 	"strings"
 	"unicode"
@@ -661,6 +662,14 @@ func ModulePath(mod []byte) string {
 	return "" // missing module path
 }
 
+func modulePathMajor(path string) (string, error) {
+	_, major, ok := module.SplitPathVersion(path)
+	if !ok {
+		return "", fmt.Errorf("invalid module path")
+	}
+	return major, nil
+}
+
 func parseString(s *string) (string, error) {
 	t := *s
 	if strings.HasPrefix(t, `"`) {
@@ -706,3 +715,81 @@ func parseVersion(verb string, path string, s *string) (string, error) {
 	*s = cv
 	return *s, nil
 }
+
+func parseReplace(filename string, line *modfile.Line, verb string, args []string) (*modfile.Replace, *modfile.Error) {
+	wrapModPathError := func(modPath string, err error) *modfile.Error {
+		return &modfile.Error{
+			Filename: filename,
+			Pos:      line.Start,
+			ModPath:  modPath,
+			Verb:     verb,
+			Err:      err,
+		}
+	}
+	wrapError := func(err error) *modfile.Error {
+		return &modfile.Error{
+			Filename: filename,
+			Pos:      line.Start,
+			Err:      err,
+		}
+	}
+	errorf := func(format string, args ...interface{}) *modfile.Error {
+		return wrapError(fmt.Errorf(format, args...))
+	}
+
+	arrow := 2
+	if len(args) >= 2 && args[1] == "=>" {
+		arrow = 1
+	}
+	if len(args) < arrow+2 || len(args) > arrow+3 || args[arrow] != "=>" {
+		return nil, errorf("usage: %s module/path [v1.2.3] => other/module v1.4\n\t or %s module/path [v1.2.3] => ../local/directory", verb, verb)
+	}
+	s, err := parseString(&args[0])
+	if err != nil {
+		return nil, errorf("invalid quoted string: %v", err)
+	}
+	pathMajor, err := modulePathMajor(s)
+	if err != nil {
+		return nil, wrapModPathError(s, err)
+	}
+	var v string
+	if arrow == 2 {
+		v, err = parseVersion(verb, s, &args[1])
+		if err != nil {
+			return nil, wrapError(err)
+		}
+		if err := module.CheckPathMajor(v, pathMajor); err != nil {
+			return nil, wrapModPathError(s, err)
+		}
+	}
+	ns, err := parseString(&args[arrow+1])
+	if err != nil {
+		return nil, errorf("invalid quoted string: %v", err)
+	}
+	nv := ""
+	if len(args) == arrow+2 {
+		if !modfile.IsDirectoryPath(ns) {
+			if strings.Contains(ns, "@") {
+				return nil, errorf("replacement module must match format 'path version', not 'path@version'")
+			}
+			return nil, errorf("replacement module without version must be directory path (rooted or starting with ./ or ../)")
+		}
+		if filepath.Separator == '/' && strings.Contains(ns, `\`) {
+			return nil, errorf("replacement directory appears to be Windows path (on a non-windows system)")
+		}
+	}
+	if len(args) == arrow+3 {
+		nv, err = parseVersion(verb, ns, &args[arrow+2])
+		if err != nil {
+			return nil, wrapError(err)
+		}
+		if modfile.IsDirectoryPath(ns) {
+			return nil, errorf("replacement module directory path %q cannot have version", ns)
+		}
+	}
+	return &modfile.Replace{
+		Old:    module.Version{Path: s, Version: v},
+		New:    module.Version{Path: ns, Version: nv},
+		Syntax: line,
+	}, nil
+}