Support for using private go modules about go-mod-vendor HOT 5 CLOSED

diff --git a/build.go b/build.go
index 4736fbe..81f8977 100644
--- a/build.go
+++ b/build.go
@@ -1,6 +1,11 @@
 package gomodvendor

 import (
+       "fmt"
+       "io"
+       "os"
+       "path/filepath"
+
        "github.com/paketo-buildpacks/packit"
 )

@@ -10,10 +15,38 @@ type BuildProcess interface {
        Execute(path, workingDir string) error
 }

+func cp(src, dst string) error {
+       in, err := os.Open(src)
+       if err != nil {
+               return fmt.Errorf("open: %w", err)
+       }
+       defer in.Close()
+
+       out, err := os.Create(dst)
+       if err != nil {
+               return fmt.Errorf("create: %w", err)
+       }
+       defer out.Close()
+
+       if _, err = io.Copy(out, in); err != nil {
+               return fmt.Errorf("copy: %w", err)
+       }
+
+       return nil
+}
+
+const netrcFromBinding = "/platform/bindings/netrc/secret/.netrc"
+
 func Build(buildProcess BuildProcess, logs LogEmitter) packit.BuildFunc {
        return func(context packit.BuildContext) (packit.BuildResult, error) {
                logs.Title("%s %s", context.BuildpackInfo.Name, context.BuildpackInfo.Version)

+               if _, err := os.Stat(netrcFromBinding); !os.IsNotExist(err) {
+                       if err := cp(netrcFromBinding, filepath.Join(os.Getenv("HOME"), ".netrc")); err != nil {
+                               return packit.BuildResult{}, fmt.Errorf("cp: %w", err)
+                       }
+               }
+
                ok, err := buildProcess.ShouldRun(context.WorkingDir)
                if err != nil {
                        return packit.BuildResult{}, err