Missing required flag error uses alias #1701
Description
My urfave/cli version is
v2.25.0
Checklist
- Are you running the latest v2 release? The list of releases is here.
- Did you check the manual for your release? The v2 manual is here <-- The link is broken, but I read the documentation.
- Did you perform a search about this problem? Here's the GitHub guide about searching.
Dependency Management
- My project is using go modules.
Describe the bug
The error message for a missing required flag uses the alias instead of the main flag name, which is not untrue, but confusing.
To reproduce
package main
import (
"fmt"
"log"
"github.com/urfave/cli/v2"
)
func main() {
app := &cli.App{
Flags: []cli.Flag{
&cli.StringFlag{
Name: "collection",
Aliases: []string{"c"},
Required: true,
},
},
Action: func(cCtx *cli.Context) error {
fmt.Println(cCtx.String("collection"))
return nil
},
}
if err := app.Run([]string{""}); err != nil {
log.Fatal(err)
}
}Observed behavior
Required flag "c" not setExpected behavior
Required flag "collection" not setAdditional context
It seems like checkRequiredFlags is iterating over the the flag names (which is the append(name, aliases...)) and sets flagName = key. After the loop is over, flagName is the last alias.
Want to fix this yourself?
I can submit a PR if you want, but according to the guidelines you are not accepting v2 fixes. Let me know if this is ok, and I'll move forward with a fix.
A fix could be:
func (cCtx *Context) checkRequiredFlags(flags []Flag) requiredFlagsErr {
var missingFlags []string
for _, f := range flags {
if rf, ok := f.(RequiredFlag); ok && rf.IsRequired() {
var flagPresent bool
var flagName string
flagNames := f.Names()
flagName = flagNames[0]
for _, key := range flagNames {
if cCtx.IsSet(strings.TrimSpace(key)) {
flagPresent = true
}
}
if !flagPresent && flagName != "" {
missingFlags = append(missingFlags, flagName)
}
}
}
if len(missingFlags) != 0 {
return &errRequiredFlags{missingFlags: missingFlags}
}
return nil
}Run go version and paste its output here
go version go1.20.2 darwin/amd64
Run go env and paste its output here
GO111MODULE=""
GOARCH="amd64"
GOBIN=""
GOCACHE="/Users/nhaas/Library/Caches/go-build"
GOENV="/Users/nhaas/Library/Application Support/go/env"
GOEXE=""
GOEXPERIMENT=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOINSECURE=""
GOMODCACHE="/Users/nhaas/go/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="darwin"
GOPATH="/Users/nhaas/go"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/usr/local/go"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/usr/local/go/pkg/tool/darwin_amd64"
GOVCS=""
GOVERSION="go1.20.2"
GCCGO="gccgo"
GOAMD64="v1"
AR="ar"
CC="clang"
CXX="clang++"
CGO_ENABLED="1"
GOMOD="/dev/null"
GOWORK="/Users/something"
CGO_CFLAGS="-O2 -g"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-O2 -g"
CGO_FFLAGS="-O2 -g"
CGO_LDFLAGS="-O2 -g"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -arch x86_64 -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/t8/83vffqv11_bbfxbbdc3fsfx40000gn/T/go-build1340975921=/tmp/go-build -gno-record-gcc-switches -fno-common"