[bugfix] Write back lockfile after devbox update

internal/devpkg/package.go

@@ -518,8 +518,8 @@ func (p *Package) ContentAddressedPath() (string, error) {
 
 	ux.Fwarning(
 		os.Stderr,
-		"calculating ca_store_path. This may be slow. "+
-			"Run `devbox update` to speed this up for next time.\n",
+		fmt.Sprintf("calculating ca_store_path for %s. This may be slow. "+
+			"Run `devbox update` to speed this up for next time.\n", sysInfo.StorePath),
 	)
 	localPath, err := nix.ContentAddressedStorePath(sysInfo.StorePath)
 	if err != nil {

internal/impl/update.go

@@ -54,6 +54,10 @@ func (d *Devbox) Update(ctx context.Context, pkgs ...string) error {
 		}
 	}
 
+	if err := d.lockfile.Save(); err != nil {
+		return err
+	}
+
 	if err := d.ensurePackagesAreInstalled(ctx, ensure); err != nil {
 		return err
 	}
@@ -107,34 +111,22 @@ func (d *Devbox) updateDevboxPackage(
 		return nil
 	}
 
-	// Check if the package's system info is missing, or not complete.
+	// Add any missing system infos for packages whose versions did not change.
 	if featureflag.RemoveNixpkgs.Enabled() {
 		userSystem, err := nix.System()
 		if err != nil {
 			return err
 		}
 
-		// If the newEntry has a system info for the user's system,
-		// then check if we need to update system info
-		if newEntry.Systems[userSystem] != nil {
-
-			// Check if the system info is missing for the user's system.
-			sysInfo := d.lockfile.Packages[pkg.Raw].Systems[userSystem]
-			if sysInfo == nil {
+		// If the newEntry has a system info for the user's system, then add/overwrite it. We don't overwrite
+		// other system infos because we don't want to clobber system-dependent CAStorePaths.
+		if newSysInfo, ok := newEntry.Systems[userSystem]; ok {
+			if !newSysInfo.Equals(existing.Systems[userSystem]) {
+				// We only guard this so that the ux messaging is accurate. We could overwrite every time.
 				if d.lockfile.Packages[pkg.Raw].Systems == nil {
 					d.lockfile.Packages[pkg.Raw].Systems = map[string]*lock.SystemInfo{}
 				}
-				d.lockfile.Packages[pkg.Raw].Systems[userSystem] = newEntry.Systems[userSystem]
-				ux.Finfo(d.writer, "Updated system information for %s\n", pkg)
-				return nil
-			}
-
-			// Check if the CAStorePath is missing for the user's system.
-			// Since any one user cannot add this field for all systems,
-			// we'll need to progressively add it to a project's lockfile.
-			if sysInfo.CAStorePath == "" {
-				// Update the CAStorePath for the user's system
-				d.lockfile.Packages[pkg.Raw].Systems[userSystem].CAStorePath = newEntry.Systems[userSystem].CAStorePath
+				d.lockfile.Packages[pkg.Raw].Systems[userSystem] = newSysInfo
 				ux.Finfo(d.writer, "Updated system information for %s\n", pkg)
 				return nil
 			}

internal/lock/package.go

@@ -22,11 +22,11 @@ type Package struct {
 type SystemInfo struct {
 	// StorePath is the input-addressed path for the nix package in /nix/store
 	// It is the cache key in the Binary Cache Store (cache.nixos.org)
-	// It is of the form <hash>-<name>-<version>
+	// It is of the form /nix/store/<hash>-<name>-<version>
 	// <name> may be different from the canonicalName so we store the full store path.
 	StorePath string `json:"store_path,omitempty"`
 	// CAStorePath is the content-addressed path for the nix package in /nix/store
-	// It is of the form <hash>-<name>-<version>
+	// It is of the form /nix/store/<hash>-<name>-<version>
 	CAStorePath string `json:"ca_store_path,omitempty"`
 }
 
@@ -43,3 +43,10 @@ func (p *Package) IsAllowInsecure() bool {
 	}
 	return p.AllowInsecure
 }
+
+func (i *SystemInfo) Equals(other *SystemInfo) bool {
+	if i == nil || other == nil {
+		return i == other
+	}
+	return *i == *other
+}