Sample

Drive a spf13/cobra command tree from a test with SetArgs and SetOut, without a subprocess, and tell the failure modes of Execute apart

sha256:40b43e1c51d66679bac8ef03d3e56f00b6f9bb2c8bc4f36791b2196260a8cce1

Case

Goal

Drive a spf13/cobra command tree from a test with SetArgs and SetOut, without a subprocess, and tell the failure modes of Execute apart HOW

Packages

github.com/spf13/cobra 1.10.2 github.com/spf13/pflag 1.0.10

Environment

go 1.26

Created

2026-08-14T12:07:26Z

Contract

• run a subcommand in memory and assert its output lands in the buffer installed with SetOut instead of on stdout
• assert RunE's error comes back out of Execute wrapped as returned, so errors.Is still reaches the sentinel
• assert Execute prints the error line to SetErr and the usage block to SetOut, so reading one buffer shows half of what the user sees
• assert SetArgs takes the arguments without the program name, and that including it makes the program name an unknown command
• assert an unset SetArgs falls back to os.Args[1:], which is what makes a command tree fail on -test flags inside go test
• assert SetArgs(nil) is that same fallback rather than an empty command line, while an empty non-nil slice runs the root with no arguments
• assert cobra skips that fallback only when the program name is cobra.test
• assert a missing required flag returns exactly required flag(s) "name" not set
• assert a child's Flags() does not contain the parent's persistent flag until parsing merges it in
• assert a persistent parent flag is readable from the child's Flags() and shows up in InheritedFlags but not LocalFlags
• assert a parent flag declared with Flags() is unknown to the child from either position on the command line, while still working on the parent
• assert the child's help lists the inherited flag under Global Flags and never lists the parent's local flag
• assert MarkFlagRequired on the child rejects a parent's persistent flag with no such flag -config, while MarkPersistentFlagRequired on the owner makes it required for the child
• assert a required flag with a default value is still an error unless it is passed explicitly, because the check is on pflag's Changed
• assert two missing required flags come back as one message with both names joined inside a single pair of quotes, ordered by pflag's sorted walk and not by declaration
• assert an unknown subcommand is an error carrying a Did you mean this suggestion, printed as a one-line pointer with no usage block
• assert an unknown flag is a different error, printed with the failing subcommand's full usage and no pointer line
• assert cobra.ArbitraryArgs on the root turns the unknown-command check off, so the typo becomes a positional argument while real subcommands still route
• assert cobra.NoArgs on the root rejects the same typo with the same wording but no suggestion and the root's whole usage block, because that error comes from ValidateArgs inside the command rather than from Find
• assert SilenceUsage on either the root or the failing command drops the usage block without changing the returned error, including for a genuine usage error
• assert SilenceUsage set inside RunE also drops the usage block, since cobra reads the field after the command returns, but leaves it in place for a flag error that never reaches RunE
• assert SilenceErrors alone drops the error line and leaves a usage block with no explanation, and that both together make Execute print nothing while still returning the error
• assert --help returns nil from Execute and prints help to the out buffer, where clap reports help as an error
• assert two Execute calls on one tree share flag state, so the second run passes the required-flag check with the first run's value

Files

• csx.json
• go.mod
• go.sum
• src/cli.go
• test/main.go

Origin Seeder

anonymous

Verification receipts

• go 1.26 · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · golang@1 · 2026-08-14 · ed25519:a2ec939a4c60e243
• · CONTAINER_RUN · compile:SKIPPED · contract:FAIL · load:SKIPPED · resolve:PASS · golang@1 · 2026-08-14 · ed25519:7da3f610facce8bf