client: show defaults when config help screen is displayed (#5896)

Closes: #5895

Thanks: @njmurarka for pointing this out.

CHANGELOG.md

@@ -185,6 +185,7 @@ allows txs to be generated without being broadcasted and disallows Keybase use a
 functionality that requires an online connection.
 * (types/module) [\#5724](https://github.com/cosmos/cosmos-sdk/issues/5724) The `types/module` package does no longer depend on `x/simulation`.
 * (client) [\#5856](https://github.com/cosmos/cosmos-sdk/pull/5856) Added the possibility to set `--offline` flag with config command.
+* (client) [\#5895](https://github.com/cosmos/cosmos-sdk/issues/5895) show config options in the config command's help screen.
 
 ## [v0.38.2] - 2020-03-25
 

client/config.go

@@ -1,12 +1,14 @@
 package client
 
 import (
+	"bytes"
 	"fmt"
 	"io"
 	"io/ioutil"
 	"os"
 	"path"
 	"strconv"
+	"text/template"
 
 	toml "github.com/pelletier/go-toml"
 	"github.com/spf13/cobra"
@@ -39,7 +41,8 @@ var configBoolDefaults = map[string]bool{
 func ConfigCmd(defaultCLIHome string) *cobra.Command {
 	cmd := &cobra.Command{
 		Use:   "config <key> [value]",
-		Short: "Create or query an application CLI configuration file",
+		Short: "Get and set client options",
+		Long:  configCommandLongDescription(),
 		RunE:  runConfigCmd,
 		Args:  cobra.RangeArgs(0, 2),
 	}
@@ -167,3 +170,22 @@ func saveConfigFile(cfgFile string, tree io.WriterTo) error {
 func errUnknownConfigKey(key string) error {
 	return fmt.Errorf("unknown configuration key: %q", key)
 }
+
+func configCommandLongDescription() string {
+	longDescTemplate := template.Must(template.New("configCommandLongDescription").
+		Parse(`{{ range $key, $value := . }}  {{ $key }} = {{ $value }}
+{{ end }}`))
+	defaultsTextBuffer := bytes.NewBufferString("")
+	must(longDescTemplate.Execute(defaultsTextBuffer, configDefaults))
+	must(longDescTemplate.Execute(defaultsTextBuffer, configBoolDefaults))
+	return fmt.Sprintf(`Display or change client application configuration values.
+
+Defaults:
+%s`, defaultsTextBuffer)
+}
+
+func must(err error) {
+	if err != nil {
+		panic(err)
+	}
+}

client/config_test.go

@@ -6,7 +6,7 @@ import (
 	"testing"
 
 	"github.com/spf13/viper"
-	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 
 	"github.com/cosmos/cosmos-sdk/client/flags"
 	"github.com/cosmos/cosmos-sdk/tests"
@@ -23,19 +23,25 @@ func Test_runConfigCmdTwiceWithShorterNodeValue(t *testing.T) {
 
 	// Init command config
 	cmd := ConfigCmd(configHome)
-	assert.NotNil(t, cmd)
-
-	err := cmd.RunE(cmd, []string{"node", "tcp://localhost:26657"})
-	assert.Nil(t, err)
+	require.NotNil(t, cmd)
+	require.NoError(t, cmd.RunE(cmd, []string{"node", "tcp://localhost:26657"}))
+	require.NoError(t, cmd.RunE(cmd, []string{"node", "--get"}))
+	require.NoError(t, cmd.RunE(cmd, []string{"node", "tcp://local:26657"}))
+	require.NoError(t, cmd.RunE(cmd, []string{"node", "--get"}))
+}
 
-	err = cmd.RunE(cmd, []string{"node", "--get"})
-	assert.Nil(t, err)
+func TestConfigCmd_UnknownOption(t *testing.T) {
+	// Prepare environment
+	configHome, cleanup := tests.NewTestCaseDir(t)
+	t.Cleanup(cleanup)
 
-	err = cmd.RunE(cmd, []string{"node", "tcp://local:26657"})
-	assert.Nil(t, err)
+	_ = os.RemoveAll(filepath.Join(configHome, "config"))
+	viper.Set(flags.FlagHome, configHome)
 
-	err = cmd.RunE(cmd, []string{"node", "--get"})
-	assert.Nil(t, err)
+	// Init command config
+	cmd := ConfigCmd(configHome)
+	require.NotNil(t, cmd)
+	require.Error(t, cmd.RunE(cmd, []string{"invalid", "true"}), "unknown configuration key: \"invalid\"")
 }
 
 func TestConfigCmd_OfflineFlag(t *testing.T) {
@@ -49,20 +55,17 @@ func TestConfigCmd_OfflineFlag(t *testing.T) {
 	// Init command config
 	cmd := ConfigCmd(configHome)
 	_, out, _ := tests.ApplyMockIO(cmd)
-	assert.NotNil(t, cmd)
+	require.NotNil(t, cmd)
 
 	viper.Set(flagGet, true)
-	err := cmd.RunE(cmd, []string{"offline"})
-	assert.Nil(t, err)
-	assert.Contains(t, out.String(), "false")
+	require.NoError(t, cmd.RunE(cmd, []string{"offline"}))
+	require.Contains(t, out.String(), "false")
 	out.Reset()
 
 	viper.Set(flagGet, false)
-	err = cmd.RunE(cmd, []string{"offline", "true"})
-	assert.Nil(t, err)
+	require.NoError(t, cmd.RunE(cmd, []string{"offline", "true"}))
 
 	viper.Set(flagGet, true)
-	err = cmd.RunE(cmd, []string{"offline"})
-	assert.Nil(t, err)
-	assert.Contains(t, out.String(), "true")
+	require.NoError(t, cmd.RunE(cmd, []string{"offline"}))
+	require.Contains(t, out.String(), "true")
 }