fix:(go) run go mod tidy before parsing (cloudwego#18)

Author: AsterDY

lang/golang/parser/parser.go

@@ -15,13 +15,15 @@
 package parser
 
 import (
+	"bytes"
 	"fmt"
 	"go/ast"
 	"go/parser"
 	"go/token"
 	"go/types"
 	"io/fs"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"regexp"
 	"strings"
@@ -142,6 +144,15 @@ func (p *GoParser) ParseRepo() (Repository, error) {
 
 func (p *GoParser) ParseModule(mod *Module, dir string) (err error) {
 	filepath.Walk(dir, func(path string, info fs.FileInfo, e error) error {
+		// run go mod tidy before parse
+		cmd := exec.Command("go", "mod", "tidy")
+		cmd.Dir = dir
+		buf := bytes.NewBuffer(nil)
+		cmd.Stderr = buf
+		if err := cmd.Run(); err != nil {
+			return fmt.Errorf("run go mod tidy failed in %s: %v", dir, buf.String())
+		}
+
 		if info != nil && info.IsDir() && filepath.Base(path) == ".git" {
 			return filepath.SkipDir
 		}

lang/golang/parser/pkg.go

@@ -151,7 +151,7 @@ func (p *GoParser) loadPackages(mod *Module, dir string, pkgPath PkgPath) (err e
 	if mm := p.repo.Modules[mod.Name]; mm != nil && (*mm).Packages[pkgPath] != nil {
 		return nil
 	}
-	fmt.Fprintf(os.Stderr, "[loadPackages] mod: %s, dir: %s, pkgPath: %s", mod.Name, dir, pkgPath)
+	fmt.Fprintf(os.Stderr, "[loadPackages] mod: %s, dir: %s, pkgPath: %s\n", mod.Name, dir, pkgPath)
 	fset := token.NewFileSet()
 	loadCount++
 	// slow-path: load packages in the dir, including sub pakcages
@@ -181,6 +181,10 @@ func (p *GoParser) loadPackages(mod *Module, dir string, pkgPath PkgPath) (err e
 		}
 	next_file:
 		for idx, file := range pkg.Syntax {
+			if idx >= len(pkg.GoFiles) {
+				fmt.Fprintf(os.Stderr, "skip file %s by loader\n", file.Name)
+				continue
+			}
 			filePath := pkg.GoFiles[idx]
 			for _, exclude := range p.exclues {
 				if exclude.MatchString(filePath) {