fix: build with go 1.23 by tracking modules.txt

builder/default.nix

@@ -106,11 +106,13 @@ let
 
         sources = toJSON (filterAttrs (n: _: n != defaultPackage) sources);
 
+        vendorModules = modulesStruct.vendorModulesTxt or "";
+
         passthru = {
           inherit sources;
         };
 
-        passAsFile = [ "json" "sources" ];
+        passAsFile = [ "json" "sources" "vendorModules" ];
       }
       (
         ''
@@ -122,6 +124,8 @@ let
           ${internal.symlink}
           ${concatStringsSep "\n" localReplaceCommands}
 
+          cp $vendorModulesPath vendor/modules.txt
+
           mv vendor $out
         ''
       );

gomod2nix.toml

@@ -1,4 +1,5 @@
-schema = 3
+schema = 4
+vendorModulesTxt = "# github.com/BurntSushi/toml v1.3.2\n## explicit; go 1.16\ngithub.com/BurntSushi/toml\ngithub.com/BurntSushi/toml/internal\n# github.com/inconshreveable/mousetrap v1.1.0\n## explicit; go 1.18\ngithub.com/inconshreveable/mousetrap\n# github.com/nix-community/go-nix v0.0.0-20220612195009-5f5614f7ca47\n## explicit; go 1.15\ngithub.com/nix-community/go-nix/pkg/nar\ngithub.com/nix-community/go-nix/pkg/wire\n# github.com/sirupsen/logrus v1.9.3\n## explicit; go 1.13\ngithub.com/sirupsen/logrus\n# github.com/spf13/cobra v1.8.0\n## explicit; go 1.15\ngithub.com/spf13/cobra\n# github.com/spf13/pflag v1.0.5\n## explicit; go 1.12\ngithub.com/spf13/pflag\n# golang.org/x/mod v0.14.0\n## explicit; go 1.18\ngolang.org/x/mod/internal/lazyregexp\ngolang.org/x/mod/modfile\ngolang.org/x/mod/module\ngolang.org/x/mod/semver\n# golang.org/x/sys v0.14.0\n## explicit; go 1.18\ngolang.org/x/sys/execabs\ngolang.org/x/sys/unix\ngolang.org/x/sys/windows\n# golang.org/x/tools/go/vcs v0.1.0-deprecated\n## explicit; go 1.19\ngolang.org/x/tools/go/vcs\n"
 
 [mod]
   [mod."github.com/BurntSushi/toml"]

internal/cmd/root.go

@@ -5,10 +5,10 @@ import (
 	"os"
 	"path/filepath"
 
-	log "github.com/sirupsen/logrus"
-	"github.com/spf13/cobra"
 	generate "github.com/nix-community/gomod2nix/internal/generate"
 	schema "github.com/nix-community/gomod2nix/internal/schema"
+	log "github.com/sirupsen/logrus"
+	"github.com/spf13/cobra"
 )
 
 const directoryDefault = "./"
@@ -62,7 +62,7 @@ func generateFunc(cmd *cobra.Command, args []string) {
 	{
 		goMod2NixPath := filepath.Join(outDir, "gomod2nix.toml")
 		outFile := goMod2NixPath
-		pkgs, err := generate.GeneratePkgs(directory, goMod2NixPath, maxJobs)
+		generated, err := generate.GeneratePkgs(directory, goMod2NixPath, maxJobs)
 		if err != nil {
 			panic(fmt.Errorf("error generating pkgs: %v", err))
 		}
@@ -75,7 +75,7 @@ func generateFunc(cmd *cobra.Command, args []string) {
 			goPackagePath = tmpProj.GoPackagePath
 		}
 
-		output, err := schema.Marshal(pkgs, goPackagePath, subPackages)
+		output, err := schema.Marshal(generated, goPackagePath, subPackages)
 		if err != nil {
 			panic(fmt.Errorf("error marshaling output: %v", err))
 		}

internal/generate/generate.go

@@ -140,7 +140,7 @@ builtins.filterSource (name: type: baseNameOf name != ".DS_Store") (
 	return executor.Wait()
 }
 
-func GeneratePkgs(directory string, goMod2NixPath string, numWorkers int) ([]*schema.Package, error) {
+func GeneratePkgs(directory string, goMod2NixPath string, numWorkers int) (*schema.GeneratePkgsResult, error) {
 	modDownloads, replace, err := common(directory)
 	if err != nil {
 		return nil, err
@@ -208,10 +208,44 @@ func GeneratePkgs(directory string, goMod2NixPath string, numWorkers int) ([]*sc
 		return nil, err
 	}
 
+	// Dependencies is downloaded, run `go mod vendor` to obtain `vendor/modules.txt` without reverse engineering
+	tmpVendorEnv := filepath.Join(directory, "vendor-gomod2nix")
+	err = os.RemoveAll(tmpVendorEnv)
+	if err != nil {
+		return nil, err
+	}
+	defer func() {
+		_ = os.RemoveAll(tmpVendorEnv)
+	}()
+
+	var modulesTxt string
+	{
+		log.Info("Obtaining modules.txt")
+		cmd := exec.Command(
+			"go", "mod", "vendor", "-o", tmpVendorEnv,
+		)
+		cmd.Dir = directory
+		err = cmd.Run()
+		if err != nil {
+			return nil, err
+		}
+		modulesTxtBytes, err := os.ReadFile(filepath.Join(tmpVendorEnv, "modules.txt"))
+		if err != nil {
+			return nil, err
+		}
+		if len(modulesTxtBytes) == 0 {
+			return nil, fmt.Errorf("modules.txt has no content")
+		}
+		modulesTxt = string(modulesTxtBytes)
+	}
+
 	sort.Slice(packages, func(i, j int) bool {
 		return packages[i].GoPackagePath < packages[j].GoPackagePath
 	})
 
-	return packages, nil
+	return &schema.GeneratePkgsResult{
+		Packages:   packages,
+		ModulesTxt: string(modulesTxt),
+	}, nil
 
 }

internal/schema/schema.go

@@ -2,11 +2,12 @@ package types
 
 import (
 	"bytes"
-	"github.com/BurntSushi/toml"
 	"os"
+
+	"github.com/BurntSushi/toml"
 )
 
-const SchemaVersion = 3
+const SchemaVersion = 4
 
 type Package struct {
 	GoPackagePath string `toml:"-"`
@@ -18,6 +19,7 @@ type Package struct {
 type Output struct {
 	SchemaVersion int                 `toml:"schema"`
 	Mod           map[string]*Package `toml:"mod"`
+	VendorModules string              `toml:"vendorModulesTxt"`
 
 	// Packages with passed import paths trigger `go install` based on this list
 	SubPackages []string `toml:"subPackages,omitempty"`
@@ -26,15 +28,21 @@ type Output struct {
 	GoPackagePath string `toml:"goPackagePath,omitempty"`
 }
 
-func Marshal(pkgs []*Package, goPackagePath string, subPackages []string) ([]byte, error) {
+type GeneratePkgsResult struct {
+	Packages   []*Package
+	ModulesTxt string
+}
+
+func Marshal(generated *GeneratePkgsResult, goPackagePath string, subPackages []string) ([]byte, error) {
 	out := &Output{
 		SchemaVersion: SchemaVersion,
 		Mod:           make(map[string]*Package),
 		SubPackages:   subPackages,
 		GoPackagePath: goPackagePath,
+		VendorModules: generated.ModulesTxt,
 	}
 
-	for _, pkg := range pkgs {
+	for _, pkg := range generated.Packages {
 		out.Mod[pkg.GoPackagePath] = pkg
 	}