Fix/dagger edit: wrong dir Path leads to infinite loop

Signed-off-by: Guillaume de Rouville <guillaume.derouville@gmail.com>

state/input.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
+	"os"
 	"path"
 	"path/filepath"
 	"strings"
@@ -113,6 +114,10 @@ func (dir dirInput) Compile(_ string, state *State) (*compiler.Value, error) {
 	if !strings.HasPrefix(p, state.Project) {
 		return nil, fmt.Errorf("%q is outside the project", dir.Path)
 	}
+	// Check that directory exists
+	if _, err := os.Stat(p); os.IsNotExist(err) {
+		return nil, fmt.Errorf("%q dir doesn't exist", dir.Path)
+	}
 
 	llb := fmt.Sprintf(
 		`#up: [{do:"local",dir:"%s", include:%s, exclude:%s}]`,