cosmos-sdk/version/command.go
Mark Rushakoff e7097b1468
test: add cmdtest package (#15251)
## Description

This PR introduces the `cmdtest` package, offering a lightweight wrapper around cobra commands to simplify testing CLI utilities.

I backfilled tests for the `version` command, which was an example of a very simple test setup; and for the `export` command, which was more involved due to the server and client context requirements.

I did notice that there are some existing tests for some utilities, but the `cmdtest` package follows a simple pattern that has been easy to use successfully in [the relayer](https://github.com/cosmos/relayer/blob/main/internal/relayertest/system.go) and in other projects outside the Cosmos ecosystem.

While filling in these tests, I started removing uses of `cmd.Print`, as that is the root cause of issues like #8498, #7964, #15167, and possibly others. Internal to cobra, the print family of methods write to `cmd.OutOrStderr()` -- meaning that if the authors call `cmd.SetOutput()` before executing the command, the output will be written to stdout as expected; otherwise it will go to stderr. I don't understand why that would be the default behavior, but it is probably too late to change from cobra's side.

Instead of `cmd.Print`, we prefer to `fmt.Fprint(cmd.OutOrStdout())` or `fmt.Fprint(cmd.ErrOrStderr())` as appropriate, giving an unambiguous destination for output. And the new tests collect those outputs in plain `bytes.Buffer` values so that we can assert their content appropriately.

In the longer term, I would like to deprecate and eventually remove the `testutil` package's `ApplyMockIO` method and its `BufferWriter` and `BufferReader` types, as they are unnecessary indirection when a simpler solution exists. But that can wait until `cmdtest` has propagated through the codebase more.

---

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2023-03-06 19:40:24 +00:00

57 lines
1.2 KiB
Go

package version
import (
"encoding/json"
"fmt"
"strings"
"github.com/cometbft/cometbft/libs/cli"
"github.com/spf13/cobra"
"sigs.k8s.io/yaml"
)
const flagLong = "long"
// NewVersionCommand returns a CLI command to interactively print the application binary version information.
func NewVersionCommand() *cobra.Command {
cmd := &cobra.Command{
Use: "version",
Short: "Print the application binary version information",
Args: cobra.NoArgs,
RunE: func(cmd *cobra.Command, _ []string) error {
verInfo := NewInfo()
if long, _ := cmd.Flags().GetBool(flagLong); !long {
fmt.Fprintln(cmd.OutOrStdout(), verInfo.Version)
return nil
}
var (
bz []byte
err error
)
output, _ := cmd.Flags().GetString(cli.OutputFlag)
switch strings.ToLower(output) {
case "json":
bz, err = json.Marshal(verInfo)
default:
bz, err = yaml.Marshal(&verInfo)
}
if err != nil {
return err
}
fmt.Fprintln(cmd.OutOrStdout(), string(bz))
return nil
},
}
cmd.Flags().Bool(flagLong, false, "Print long version information")
cmd.Flags().StringP(cli.OutputFlag, "o", "text", "Output format (text|json)")
return cmd
}