1 files changed, 142 insertions, 0 deletions
diff --git a/cli/internal/fs/package_json.go b/cli/internal/fs/package_json.go
new file mode 100644
index 0000000..883f7a4
--- /dev/null
+++ b/cli/internal/fs/package_json.go
@@ -0,0 +1,142 @@
+package fs
+
+import (
+	"bytes"
+	"encoding/json"
+	"sync"
+
+	"github.com/vercel/turbo/cli/internal/lockfile"
+	"github.com/vercel/turbo/cli/internal/turbopath"
+)
+
+// PackageJSON represents NodeJS package.json
+type PackageJSON struct {
+	Name                 string            `json:"name"`
+	Version              string            `json:"version"`
+	Scripts              map[string]string `json:"scripts"`
+	Dependencies         map[string]string `json:"dependencies"`
+	DevDependencies      map[string]string `json:"devDependencies"`
+	OptionalDependencies map[string]string `json:"optionalDependencies"`
+	PeerDependencies     map[string]string `json:"peerDependencies"`
+	PackageManager       string            `json:"packageManager"`
+	Os                   []string          `json:"os"`
+	Workspaces           Workspaces        `json:"workspaces"`
+	Private              bool              `json:"private"`
+	// Exact JSON object stored in package.json including unknown fields
+	// During marshalling struct fields will take priority over raw fields
+	RawJSON map[string]interface{} `json:"-"`
+
+	// relative path from repo root to the package.json file
+	PackageJSONPath turbopath.AnchoredSystemPath `json:"-"`
+	// relative path from repo root to the package
+	Dir                    turbopath.AnchoredSystemPath `json:"-"`
+	InternalDeps           []string                     `json:"-"`
+	UnresolvedExternalDeps map[string]string            `json:"-"`
+	TransitiveDeps         []lockfile.Package           `json:"-"`
+	LegacyTurboConfig      *TurboJSON                   `json:"turbo"`
+	Mu                     sync.Mutex                   `json:"-"`
+	ExternalDepsHash       string                       `json:"-"`
+}
+
+type Workspaces []string
+
+type WorkspacesAlt struct {
+	Packages []string `json:"packages,omitempty"`
+}
+
+func (r *Workspaces) UnmarshalJSON(data []byte) error {
+	var tmp = &WorkspacesAlt{}
+	if err := json.Unmarshal(data, tmp); err == nil {
+		*r = Workspaces(tmp.Packages)
+		return nil
+	}
+	var tempstr = []string{}
+	if err := json.Unmarshal(data, &tempstr); err != nil {
+		return err
+	}
+	*r = tempstr
+	return nil
+}
+
+// ReadPackageJSON returns a struct of package.json
+func ReadPackageJSON(path turbopath.AbsoluteSystemPath) (*PackageJSON, error) {
+	b, err := path.ReadFile()
+	if err != nil {
+		return nil, err
+	}
+	return UnmarshalPackageJSON(b)
+}
+
+// UnmarshalPackageJSON decodes a byte slice into a PackageJSON struct
+func UnmarshalPackageJSON(data []byte) (*PackageJSON, error) {
+	var rawJSON map[string]interface{}
+	if err := json.Unmarshal(data, &rawJSON); err != nil {
+		return nil, err
+	}
+
+	pkgJSON := &PackageJSON{}
+	if err := json.Unmarshal(data, &pkgJSON); err != nil {
+		return nil, err
+	}
+	pkgJSON.RawJSON = rawJSON
+
+	return pkgJSON, nil
+}
+
+// MarshalPackageJSON Serialize PackageJSON to a slice of bytes
+func MarshalPackageJSON(pkgJSON *PackageJSON) ([]byte, error) {
+	structuredContent, err := json.Marshal(pkgJSON)
+	if err != nil {
+		return nil, err
+	}
+	var structuredFields map[string]interface{}
+	if err := json.Unmarshal(structuredContent, &structuredFields); err != nil {
+		return nil, err
+	}
+
+	fieldsToSerialize := make(map[string]interface{}, len(pkgJSON.RawJSON))
+
+	// copy pkgJSON.RawJSON
+	for key, value := range pkgJSON.RawJSON {
+		fieldsToSerialize[key] = value
+	}
+
+	for key, value := range structuredFields {
+		if isEmpty(value) {
+			delete(fieldsToSerialize, key)
+		} else {
+			fieldsToSerialize[key] = value
+		}
+	}
+
+	var b bytes.Buffer
+	encoder := json.NewEncoder(&b)
+	encoder.SetEscapeHTML(false)
+	encoder.SetIndent("", "  ")
+	if err := encoder.Encode(fieldsToSerialize); err != nil {
+		return nil, err
+	}
+
+	return b.Bytes(), nil
+}
+
+func isEmpty(value interface{}) bool {
+	if value == nil {
+		return true
+	}
+	switch s := value.(type) {
+	case string:
+		return s == ""
+	case bool:
+		return !s
+	case []string:
+		return len(s) == 0
+	case map[string]interface{}:
+		return len(s) == 0
+	case Workspaces:
+		return len(s) == 0
+	default:
+		// Assume any unknown types aren't empty
+		return false
+	}
+}