move fs bridge to launcher

Signed-off-by: Pablo Chacin <pablochacin@gmail.com>

Author: pablochacin

internal/cmd/launcher.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
+	"io/fs"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -20,6 +21,27 @@ import (
 	"go.k6.io/k6/lib/fsext"
 )
 
+// OFSBridge allows an afero.Fs to implement the Go standard library io/fs.FS.
+type iofSBridge struct {
+	fsext fsext.Fs
+}
+
+// newIofsBridge returns an IOFSBridge from a Fs
+func newIofsBridge(fs fsext.Fs) fs.FS {
+	return &iofSBridge{
+		fsext: fs,
+	}
+}
+
+// Open implements fs.Fs Open
+func (b *iofSBridge) Open(name string) (fs.File, error) {
+	f, err := b.fsext.Open(name)
+	if err != nil {
+		return nil, fmt.Errorf("opening file: %w", err)
+	}
+	return f, nil
+}
+
 // commandExecutor executes the requested k6 command line command.
 // It abstract the execution path from the concrete binary.
 type commandExecutor interface {
@@ -308,7 +330,7 @@ func analyze(gs *state.GlobalState, args []string) (k6deps.Dependencies, error)
 		}
 		dopts.Script.Name = sourceRootPath
 		dopts.Script.Contents = src.Data
-		dopts.Fs = fsext.NewIOFSBridge(gs.FS)
+		dopts.Fs = newIofsBridge(gs.FS)
 	}
 
 	return k6deps.Analyze(dopts)

internal/cmd/launcher_test.go

@@ -4,13 +4,16 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
+	"io"
+	"io/fs"
 	"os"
 	"path/filepath"
 	"testing"
 
 	"github.com/grafana/k6deps"
 	"github.com/spf13/cobra"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"go.k6.io/k6/cmd/state"
 
 	"go.k6.io/k6/errext"
@@ -394,3 +397,23 @@ func TestIsAnalysisRequired(t *testing.T) {
 		})
 	}
 }
+
+func TestBridgeOpen(t *testing.T) {
+	t.Parallel()
+
+	testfs := afero.NewMemMapFs()
+	require.NoError(t, fsext.WriteFile(testfs, "abasicpath/onetwo.txt", []byte(`test123`), 0o644))
+
+	bridge := &iofSBridge{fsext: testfs}
+
+	// it asserts that bridge implements io/fs.FS
+	goiofs := fs.FS(bridge)
+	f, err := goiofs.Open("abasicpath/onetwo.txt")
+	require.NoError(t, err)
+	require.NotNil(t, f)
+
+	content, err := io.ReadAll(f)
+	require.NoError(t, err)
+
+	assert.Equal(t, "test123", string(content))
+}