fix: remove panic case from conflicting configs

application.go

@@ -23,13 +23,13 @@ type Initializer func(*State) error
 
 type PostRun func(*State, error)
 
-type postConstruct func(*application)
+type postConstruct func(*application) error
 
 type Application interface {
 	ID() Identification
 	AddFlags(flags *pflag.FlagSet, cfgs ...any)
 	SetupCommand(cmd *cobra.Command, cfgs ...any) *cobra.Command
-	SetupRootCommand(cmd *cobra.Command, cfgs ...any) *cobra.Command
+	SetupRootCommand(cmd *cobra.Command, cfgs ...any) (*cobra.Command, error)
 	Run()
 }
 
@@ -276,12 +276,12 @@ func (a *application) Run() {
 	}
 }
 
-func (a *application) SetupRootCommand(cmd *cobra.Command, cfgs ...any) *cobra.Command {
+func (a *application) SetupRootCommand(cmd *cobra.Command, cfgs ...any) (*cobra.Command, error) {
 	a.root = cmd
 	return a.setupRootCommand(cmd, cfgs...)
 }
 
-func (a *application) setupRootCommand(cmd *cobra.Command, cfgs ...any) *cobra.Command {
+func (a *application) setupRootCommand(cmd *cobra.Command, cfgs ...any) (*cobra.Command, error) {
 	if !strings.HasPrefix(cmd.Use, a.setupConfig.ID.Name) {
 		cmd.Use = a.setupConfig.ID.Name
 	}
@@ -295,10 +295,13 @@ func (a *application) setupRootCommand(cmd *cobra.Command, cfgs ...any) *cobra.C
 	a.state.Config.Dev = cp(a.setupConfig.DefaultDevelopmentConfig)
 
 	for _, pc := range a.setupConfig.postConstructs {
-		pc(a)
+		err := pc(a)
+		if err != nil {
+			return nil, err
+		}
 	}
 
-	return a.setupCommand(cmd, cmd.Flags(), &cmd.PreRunE, cfgs...)
+	return a.setupCommand(cmd, cmd.Flags(), &cmd.PreRunE, cfgs...), nil
 }
 
 func cp[T any](value *T) *T {

application_test.go

@@ -127,7 +127,7 @@ func Test_Application_Setup_WiresFangs(t *testing.T) {
 
 	app := New(*cfg)
 
-	cmd := app.SetupRootCommand(&cobra.Command{
+	cmd, _ := app.SetupRootCommand(&cobra.Command{
 		DisableFlagParsing: true,
 		Args:               cobra.ArbitraryArgs,
 		Run: func(cmd *cobra.Command, args []string) {
@@ -163,7 +163,7 @@ func Test_Application_Setup_PassLoggerConstructor(t *testing.T) {
 
 	app := New(*cfg)
 
-	cmd := app.SetupRootCommand(&cobra.Command{
+	cmd, _ := app.SetupRootCommand(&cobra.Command{
 		DisableFlagParsing: true,
 		Args:               cobra.ArbitraryArgs,
 		Run:                func(cmd *cobra.Command, args []string) {},
@@ -192,7 +192,7 @@ func Test_Application_Setup_ConfigureLogger(t *testing.T) {
 
 	app := New(*cfg)
 
-	cmd := app.SetupRootCommand(&cobra.Command{
+	cmd, _ := app.SetupRootCommand(&cobra.Command{
 		DisableFlagParsing: true,
 		Args:               cobra.ArbitraryArgs,
 		Run:                func(cmd *cobra.Command, args []string) {},
@@ -280,7 +280,7 @@ func Test_SetupCommand(t *testing.T) {
 
 	app := New(*cfg)
 
-	root := app.SetupRootCommand(&cobra.Command{})
+	root, _ := app.SetupRootCommand(&cobra.Command{})
 
 	app.AddFlags(root.PersistentFlags(), p)
 

cliotestutils/application.go

@@ -58,7 +58,7 @@ func (a *testApplication) SetupCommand(cmd *cobra.Command, cfgs ...any) *cobra.C
 	return a.Application.SetupCommand(cmd, cfgs...)
 }
 
-func (a *testApplication) SetupRootCommand(cmd *cobra.Command, cfgs ...any) *cobra.Command {
+func (a *testApplication) SetupRootCommand(cmd *cobra.Command, cfgs ...any) (*cobra.Command, error) {
 	cmd.RunE = func(cmd *cobra.Command, args []string) error {
 		a.assertion(cmd, args, cfgs...)
 		return nil

help_template.go

@@ -2,7 +2,7 @@ package clio
 
 import (
 	"fmt"
-	"reflect"
+	"log"
 
 	"github.com/spf13/cobra"
 
@@ -11,7 +11,7 @@ import (
 
 var _ postConstruct = updateHelpUsageTemplate
 
-func updateHelpUsageTemplate(a *application) {
+func updateHelpUsageTemplate(a *application) error {
 	cmd := a.root
 
 	var helpUsageTemplate = fmt.Sprintf(`{{if (or .Long .Short)}}{{.Long}}{{if not .Long}}{{.Short}}{{end}}
@@ -42,27 +42,36 @@ Use "{{if .CommandPath}}{{.CommandPath}} {{end}}[command] --help" for more infor
 
 	cmd.SetUsageTemplate(helpUsageTemplate)
 	cmd.SetHelpTemplate(helpUsageTemplate)
+	return nil
 }
 
 var _ postConstruct = showConfigInRootHelp
 
-func showConfigInRootHelp(a *application) {
+func showConfigInRootHelp(a *application) error {
 	cmd := a.root
 
 	helpFn := cmd.HelpFunc()
+	// check if the config can load before setting the help function
+	cfgs := append([]any{&a.state.Config, a}, a.state.Config.FromCommands...)
+	for _, cfg := range cfgs {
+		if err := fangs.Load(a.setupConfig.FangsConfig, cmd, cfg); err != nil {
+			return fmt.Errorf("error loading config object; do you have a config that conflicts with a newer version? %w", err)
+		}
+	}
 	cmd.SetHelpFunc(func(cmd *cobra.Command, args []string) {
 		// root.Example is set _after all added commands_ because it collects all the
 		// options structs in order to output an accurate "config file" summary
 		// note: since all commands tend to share help functions it's important to only patch the example
 		// when there is no parent command (i.e. the root command).
 		if cmd == a.root {
-			cfgs := append([]any{&a.state.Config, a}, a.state.Config.FromCommands...)
-			for _, cfg := range cfgs {
+			helpCfgs := append([]any{&a.state.Config, a}, a.state.Config.FromCommands...)
+			for _, cfg := range helpCfgs {
 				// load each config individually, as there may be conflicting names / types that will cause
 				// viper to fail to read them all and panic
 				if err := fangs.Load(a.setupConfig.FangsConfig, cmd, cfg); err != nil {
-					t := reflect.TypeOf(cfg)
-					panic(fmt.Sprintf("error loading config object: `%s:%s`: %s", t.PkgPath(), t.Name(), err.Error()))
+					// log default prints to stderr
+					log.Printf("error loading config object; do you have a config that conflicts with a newer version? %v", err)
+					return
 				}
 			}
 			summary := a.summarizeConfig(cmd)
@@ -73,4 +82,5 @@ func showConfigInRootHelp(a *application) {
 		}
 		helpFn(cmd, args)
 	})
+	return nil
 }

help_template_test.go

@@ -9,9 +9,33 @@ import (
 	"github.com/spf13/cobra"
 	"github.com/stretchr/testify/require"
 
+	"github.com/anchore/fangs"
 	"github.com/anchore/go-logger/adapter/redact"
 )
 
+// regression test for https://github.com/anchore/clio/issues/40
+func Test_conflictingConfigErrors(t *testing.T) {
+	fangsConfig := fangs.NewConfig("test")
+	fangsConfig.File = "testdata/conflicting_config.yaml"
+	application := &application{
+		root: &cobra.Command{},
+		state: State{
+			Config: Config{
+				FromCommands: []any{&struct {
+					UnderTest string `mapstructure:"test" yaml:"test"`
+				}{UnderTest: "test"}},
+			},
+		},
+		setupConfig: SetupConfig{
+			FangsConfig: fangsConfig,
+		},
+	}
+	err := showConfigInRootHelp(application)
+	require.Error(t, err)
+	msg := err.Error()
+	require.Contains(t, msg, "error loading config object")
+}
+
 func Test_redactingHelpText(t *testing.T) {
 	cfg := NewSetupConfig(Identification{
 		Name:    "app",
@@ -27,7 +51,7 @@ func Test_redactingHelpText(t *testing.T) {
 
 	app := New(*cfg)
 
-	root := app.SetupRootCommand(&cobra.Command{}, r)
+	root, _ := app.SetupRootCommand(&cobra.Command{}, r)
 
 	r.store = app.(*application).state.RedactStore
 

setup_config.go

@@ -110,15 +110,17 @@ func (c *SetupConfig) withPostConstructs(postConstructs ...postConstruct) *Setup
 
 // WithGlobalConfigFlag adds the global `-c` / `--config` flags to the root command
 func (c *SetupConfig) WithGlobalConfigFlag() *SetupConfig {
-	return c.withPostConstructs(func(a *application) {
+	return c.withPostConstructs(func(a *application) error {
 		a.AddFlags(a.root.PersistentFlags(), &a.setupConfig.FangsConfig)
+		return nil
 	})
 }
 
 // WithGlobalLoggingFlags adds the global logging flags to the root command.
 func (c *SetupConfig) WithGlobalLoggingFlags() *SetupConfig {
-	return c.withPostConstructs(func(a *application) {
+	return c.withPostConstructs(func(a *application) error {
 		a.AddFlags(a.root.PersistentFlags(), &a.state.Config)
+		return nil
 	})
 }
 

testdata/conflicting_config.yaml

@@ -0,0 +1,3 @@
+test:
+  bad: ""
+  fail: ""