Improve the output for these validation errors:
- Removes the short command description from the output. This information
does not provide much useful help, and distracts from the error message.
- Reduces punctuation, and
- Prefixes the error message with the binary / root-command name
(usually `docker:`) to be consistent with other similar errors.
- Adds an empty line between the error-message and the "call to action"
(`Run 'docker volume --help'...` in the example below). This helps
separating the error message and "usage" from the call-to-action.
Before this patch:
$ docker volume ls one two three
"docker volume ls" accepts no arguments.
See 'docker volume ls --help'.
Usage: docker volume ls [OPTIONS]
List volumes
$ docker volume create one two three
"docker volume create" requires at most 1 argument.
See 'docker volume create --help'.
Usage: docker volume create [OPTIONS] [VOLUME]
Create a volume
With this patch:
$ docker volume ls one two three
docker: 'docker volume ls' accepts no arguments
Usage: docker volume ls [OPTIONS]
Run 'docker volume ls --help' for more information
$ docker voludocker volume create one two three
docker: 'docker volume create' requires at most 1 argument
Usage: docker volume create [OPTIONS] [VOLUME]
SRun 'docker volume create --help' for more information
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This makes a quick pass through our tests;
Discard output/err
----------------------------------------------
Many tests were testing for error-conditions, but didn't discard output.
This produced a lot of noise when running the tests, and made it hard
to discover if there were actual failures, or if the output was expected.
For example:
=== RUN TestConfigCreateErrors
Error: "create" requires exactly 2 arguments.
See 'create --help'.
Usage: create [OPTIONS] CONFIG file|- [flags]
Create a config from a file or STDIN
Error: "create" requires exactly 2 arguments.
See 'create --help'.
Usage: create [OPTIONS] CONFIG file|- [flags]
Create a config from a file or STDIN
Error: error creating config
--- PASS: TestConfigCreateErrors (0.00s)
And after discarding output:
=== RUN TestConfigCreateErrors
--- PASS: TestConfigCreateErrors (0.00s)
Use sub-tests where possible
----------------------------------------------
Some tests were already set-up to use test-tables, and even had a usable
name (or in some cases "error" to check for). Change them to actual sub-
tests. Same test as above, but now with sub-tests and output discarded:
=== RUN TestConfigCreateErrors
=== RUN TestConfigCreateErrors/requires_exactly_2_arguments
=== RUN TestConfigCreateErrors/requires_exactly_2_arguments#01
=== RUN TestConfigCreateErrors/error_creating_config
--- PASS: TestConfigCreateErrors (0.00s)
--- PASS: TestConfigCreateErrors/requires_exactly_2_arguments (0.00s)
--- PASS: TestConfigCreateErrors/requires_exactly_2_arguments#01 (0.00s)
--- PASS: TestConfigCreateErrors/error_creating_config (0.00s)
PASS
It's not perfect in all cases (in the above, there's duplicate "expected"
errors, but Go conveniently adds "#01" for the duplicate). There's probably
also various tests I missed that could still use the same changes applied;
we can improve these in follow-ups.
Set cmd.Args to prevent test-failures
----------------------------------------------
When running tests from my IDE, it compiles the tests before running,
then executes the compiled binary to run the tests. Cobra doesn't like
that, because in that situation `os.Args` is taken as argument for the
command that's executed. The command that's tested now sees the test-
flags as arguments (`-test.v -test.run ..`), which causes various tests
to fail ("Command XYZ does not accept arguments").
# compile the tests:
go test -c -o foo.test
# execute the test:
./foo.test -test.v -test.run TestFoo
=== RUN TestFoo
Error: "foo" accepts no arguments.
The Cobra maintainers ran into the same situation, and for their own
use have added a special case to ignore `os.Args` in these cases;
https://github.com/spf13/cobra/blob/v1.8.1/command.go#L1078-L1083
args := c.args
// Workaround FAIL with "go test -v" or "cobra.test -test.v", see #155
if c.args == nil && filepath.Base(os.Args[0]) != "cobra.test" {
args = os.Args[1:]
}
Unfortunately, that exception is too specific (only checks for `cobra.test`),
so doesn't automatically fix the issue for other test-binaries. They did
provide a `cmd.SetArgs()` utility for this purpose
https://github.com/spf13/cobra/blob/v1.8.1/command.go#L276-L280
// SetArgs sets arguments for the command. It is set to os.Args[1:] by default, if desired, can be overridden
// particularly useful when testing.
func (c *Command) SetArgs(a []string) {
c.args = a
}
And the fix is to explicitly set the command's args to an empty slice to
prevent Cobra from falling back to using `os.Args[1:]` as arguments.
cmd := newSomeThingCommand()
cmd.SetArgs([]string{})
Some tests already take this issue into account, and I updated some tests
for this, but there's likely many other ones that can use the same treatment.
Perhaps the Cobra maintainers would accept a contribution to make their
condition less specific and to look for binaries ending with a `.test`
suffix (which is what compiled binaries usually are named as).
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Sebastiaan van Stijn
Vincent Demeester
Daniel Nephin
Daniel Nephin