Re: [PATCH for-5.0 v2 3/3] iotests/138: Test leaks/corruptions fixed report

[Eric Blake <eblake@redhat.com>]

On 3/24/20 12:27 PM, Max Reitz wrote:
> Test that qemu-img check reports the number of leaks and corruptions
> fixed in its JSON report (after a successful run).
> 
> While touching the _unsupported_imgopts line, adjust the note on why
> data_file does not work with this test: The current comment sounds a bit
> like it is a mistake for qemu-img check not to check external data
> files' refcounts.  But there are no such refcounts, so it is no mistake.
> Just say that qemu-img check does not do much for external data files,
> and this is why this test does not work with them.
> 
> Signed-off-by: Max Reitz <mreitz@redhat.com>
> ---
>   tests/qemu-iotests/138     | 41 ++++++++++++++++++++++++++++++++++++--
>   tests/qemu-iotests/138.out | 14 +++++++++++++
>   2 files changed, 53 insertions(+), 2 deletions(-)
> 
> diff --git a/tests/qemu-iotests/138 b/tests/qemu-iotests/138
> index 54b01046ad..1d5b0bed6d 100755
> --- a/tests/qemu-iotests/138
> +++ b/tests/qemu-iotests/138
> @@ -41,8 +41,10 @@ _supported_fmt qcow2
>   _supported_proto file
>   _supported_os Linux
>   # With an external data file, data clusters are not refcounted
> -# (and so qemu-img check does not check their refcount)
> -_unsupported_imgopts data_file
> +# (so qemu-img check would not do much);

Works for me.

> +echo
> +# Should print the number of corruptions and leaks fixed
> +# (Filter out all JSON fields (recognizable by their four-space
> +# indentation), but keep the "-fixed" fields (by removing two spaces
> +# from their indentation))
> +# (Also filter out the L1 entry, because why not)
> +_check_test_img -r all --output=json \
> +    | sed -e 's/^  \(.*\)-fixed"/\1-fixed"/' \
> +          -e '/^    /d' \
> +          -e "s/\\([^0-9a-f]\\)$(printf %x $l1_entry)\\([^0-9a-f]\\)/\1L1_ENTRY_VALUE\2/"

It's fun to see the post-review results.  Given the limited times where 
the third -e fires in the output,

> +++ b/tests/qemu-iotests/138.out

> +Leaked cluster 0 refcount=2 reference=1
> +Repairing cluster 0 refcount=2 reference=1
> +Repairing OFLAG_COPIED L2 cluster: l1_index=0 l1_entry=L1_ENTRY_VALUE refcount=1

it could be written with less typing as:

-e "s/=$(printf %x $l1_entry) /=L1_ENTRY_VALUE /"

but that's not essential.  So either way,

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
Virtualization:  qemu.org | libvirt.org