Make error message instructional for the case of lock file being out of date

Signed-off-by: Andreas Sommer <andreas.sommer87@googlemail.com>

pkg/cmd/install.go

@@ -304,7 +304,7 @@ func runInstall(args []string, client *action.Install, valueOpts *values.Options
 					return nil, fmt.Errorf("failed reloading chart after repo update: %w", err)
 				}
 			} else {
-				return nil, fmt.Errorf("an error occurred while checking for chart dependencies. You may need to run `helm dependency build` to fetch missing dependencies: %w", err)
+				return nil, fmt.Errorf("an error occurred while checking for chart dependencies. You may need to run 'helm dependency build' to fetch missing dependencies: %w", err)
 			}
 		}
 	}

pkg/cmd/testdata/output/upgrade-with-missing-dependencies.txt

@@ -1 +1 @@
-Error: an error occurred while checking for chart dependencies. You may need to run `helm dependency build` to fetch missing dependencies: found in Chart.yaml, but missing in charts/ directory: reqsubchart2
+Error: an error occurred while checking for chart dependencies. You may need to run 'helm dependency build' to fetch missing dependencies: found in Chart.yaml, but missing in charts/ directory: reqsubchart2

pkg/cmd/upgrade.go

@@ -200,7 +200,7 @@ func newUpgradeCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
 			}
 			if req := ch.Metadata.Dependencies; req != nil {
 				if err := action.CheckDependencies(ch, req); err != nil {
-					err = fmt.Errorf("an error occurred while checking for chart dependencies. You may need to run `helm dependency build` to fetch missing dependencies: %w", err)
+					err = fmt.Errorf("an error occurred while checking for chart dependencies. You may need to run 'helm dependency build' to fetch missing dependencies: %w", err)
 					if client.DependencyUpdate {
 						man := &downloader.Manager{
 							Out:              out,

pkg/downloader/manager.go

@@ -127,7 +127,7 @@ func (m *Manager) Build() error {
 				return errors.New("the lock file (requirements.lock) is out of sync with the dependencies file (requirements.yaml). Please update the dependencies")
 			}
 		} else {
-			return errors.New("the lock file (Chart.lock) is out of sync with the dependencies file (Chart.yaml). Please update the dependencies")
+			return errors.New("the lock file (Chart.lock) is out of sync with the dependencies file (Chart.yaml). Please update the dependencies with 'helm dependency update'")
 		}
 	}