consolidate pod and clean up errlogs

internal/docker/docker.go

@@ -144,8 +144,8 @@ func (d *Client) Run(ctx context.Context, req *Request) (string, error) {
 
 					if inspect.State != nil && inspect.State.Health != nil {
 						if inspect.State.Health.Status == "unhealthy" {
-							status := inspect.State.Health.Log[len(inspect.State.Health.Log)-1].Output
-							unhealthyCh <- fmt.Errorf("container became unhealthy, last status: %s", status)
+							code := inspect.State.Health.Log[len(inspect.State.Health.Log)-1].ExitCode
+							unhealthyCh <- fmt.Errorf("container became unhealthy with exit code: %d", code)
 							return
 						}
 					}
@@ -164,11 +164,11 @@ func (d *Client) Run(ctx context.Context, req *Request) (string, error) {
 
 	case status := <-statusCh:
 		if status.Error != nil {
-			return "", fmt.Errorf("container exited with error: %s", status.Error.Message)
+			return "", fmt.Errorf("container exited with error (%d): %s", status.StatusCode, status.Error.Message)
 		}
 
 		if status.StatusCode != 0 {
-			return "", fmt.Errorf("container exited with non-zero status code: %d", status.StatusCode)
+			return "", fmt.Errorf("container exited with non-zero exit code: %v", status.StatusCode)
 		}
 
 	case err := <-unhealthyCh:

internal/drivers/docker_in_docker/driver.go

@@ -2,6 +2,7 @@ package dockerindocker
 
 import (
 	"bufio"
+	"bytes"
 	"context"
 	"encoding/json"
 	"fmt"
@@ -140,6 +141,10 @@ func (d *driver) Run(ctx context.Context, ref name.Reference) error {
 	r, w := io.Pipe()
 	defer w.Close()
 
+	// collect container output for better error messages
+	stw := bytes.NewBuffer(nil)
+	mw := io.MultiWriter(w, stw)
+
 	go func() {
 		defer r.Close()
 		scanner := bufio.NewScanner(r)
@@ -168,10 +173,10 @@ func (d *driver) Run(ctx context.Context, ref name.Reference) error {
 		},
 		ExtraHosts: []string{"host.docker.internal:host-gateway"},
 		Contents:   content,
-		Logger:     w,
+		Logger:     mw,
 	})
 	if err != nil {
-		return err
+		return fmt.Errorf("docker-in-docker test failed: %w\n\n%s", err, stw.String())
 	}
 
 	if err := d.stack.Add(func(ctx context.Context) error {