[config] look for the devbox.json file in parent directories as well

devbox.go

@@ -12,6 +12,7 @@ import (
 	"github.com/pkg/errors"
 	"go.jetpack.io/devbox/boxcli/usererr"
 	"go.jetpack.io/devbox/cuecfg"
+	"go.jetpack.io/devbox/debug"
 	"go.jetpack.io/devbox/docker"
 	"go.jetpack.io/devbox/nix"
 	"go.jetpack.io/devbox/pkgslice"
@@ -33,17 +34,19 @@ func InitConfig(dir string) (created bool, err error) {
 // Devbox provides an isolated development environment that contains a set of
 // Nix packages.
 type Devbox struct {
-	cfg    *Config
+	cfg *Config
+	// srcDir is the directory where the config file (devbox.json) resides
 	srcDir string
 }
 
 // Open opens a devbox by reading the config file in dir.
 func Open(dir string) (*Devbox, error) {
-	cfgPath := filepath.Join(dir, configFilename)
 
-	if !plansdk.FileExists(cfgPath) {
-		return nil, missingDevboxJSONError(dir)
+	cfgDir, err := findConfigDir(dir)
+	if err != nil {
+		return nil, err
 	}
+	cfgPath := filepath.Join(cfgDir, configFilename)
 
 	cfg, err := ReadConfig(cfgPath)
 	if err != nil {
@@ -52,7 +55,7 @@ func Open(dir string) (*Devbox, error) {
 
 	box := &Devbox{
 		cfg:    cfg,
-		srcDir: dir,
+		srcDir: cfgDir,
 	}
 	return box, nil
 }
@@ -226,7 +229,7 @@ func (d *Devbox) generateBuildFiles() error {
 func missingDevboxJSONError(dir string) error {
 
 	// We try to prettify the `dir` before printing
-	if dir == "." {
+	if dir == "." || dir == "" {
 		dir = "this directory"
 	} else {
 		// Instead of a long absolute directory, print the relative directory
@@ -240,5 +243,26 @@ func missingDevboxJSONError(dir string) error {
 			}
 		}
 	}
-	return usererr.New("No devbox.json found in %s. Did you run `devbox init` yet?", dir)
+	return usererr.New("No devbox.json found in %s, or any parent directories. Did you run `devbox init` yet?", dir)
+}
+
+func findConfigDir(dir string) (string, error) {
+
+	// Sanitize the directory and use the absolute path as canonical form
+	cur, err := filepath.Abs(dir)
+	if err != nil {
+		return "", errors.WithStack(err)
+	}
+
+	for cur != "/" {
+		debug.Log("finding %s in dir: %s\n", configFilename, cur)
+		if plansdk.FileExists(filepath.Join(cur, configFilename)) {
+			return cur, nil
+		}
+		cur = filepath.Dir(cur)
+	}
+	if plansdk.FileExists(filepath.Join(cur, configFilename)) {
+		return cur, nil
+	}
+	return "", missingDevboxJSONError(dir)
 }

devbox_test.go

@@ -8,6 +8,7 @@ import (
 
 	"github.com/bmatcuk/doublestar/v4"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"go.jetpack.io/devbox/planner/plansdk"
 )
 
@@ -28,6 +29,10 @@ func TestDevbox(t *testing.T) {
 }
 
 func testExample(t *testing.T, testPath string) {
+
+	currentDir, err := os.Getwd()
+	require.New(t).NoError(err)
+
 	baseDir := filepath.Dir(testPath)
 	t.Run(baseDir, func(t *testing.T) {
 		assert := assert.New(t)
@@ -36,6 +41,13 @@ func testExample(t *testing.T, testPath string) {
 
 		box, err := Open(baseDir)
 		assert.NoErrorf(err, "%s should be a valid devbox project", baseDir)
+
+		// Just for tests, we make srcDir be a relative path so that the paths in plan.json
+		// of various test cases have relative paths. Absolute paths are a no-go because they'd
+		// be of the form `/Users/savil/...`, which are not generalized and cannot be checked in.
+		box.srcDir, err = filepath.Rel(currentDir, box.srcDir)
+		assert.NoErrorf(err, "expect to construct relative path from %s relative to base %s", box.srcDir, currentDir)
+
 		plan, err := box.ShellPlan()
 		assert.NoError(err, "devbox plan should not fail")