Re: [Qemu-devel] [PATCH v2 11/14] qlit: improve QLit dict vs qdict comparison

[Markus Armbruster <armbru@redhat.com>]

Marc-André Lureau <marcandre.lureau@redhat.com> writes:

> Verify that all qdict values are covered.
>
> (a previous iteration of this patch created a copy of qdict to remove
> all checked elements, verifying no duplicates exist in the literal
> qdict, however this is a programming error, and a size comparison
> should be enough)

The parenthesis confused me, because I wasn't sure about the exact
meaning of "a previous iteration of this patch".  I tried to find a
prior commit, but it looks like you're really talking about v1.
Confused me, because I don't expect commit messages discussing previous
iterations.

What about:

    qlit: Tighten QLit dict vs qdict comparison

    We check that all members of the QLit dictionary are also in the
    QDict.  We neglect to check the other direction.

    Comparing the number of members suffices, because QDict can't
    contain duplicate members, and putting duplicates in a QLit is a
    programming error.

> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
>  qobject/qlit.c     | 37 +++++++++++++++++++++++--------------
>  tests/check-qlit.c |  7 +++++++
>  2 files changed, 30 insertions(+), 14 deletions(-)
>
> diff --git a/qobject/qlit.c b/qobject/qlit.c
> index b1d9146220..dc0015f76c 100644
> --- a/qobject/qlit.c
> +++ b/qobject/qlit.c
> @@ -41,6 +41,27 @@ static void compare_helper(QObject *obj, void *opaque)
>          qlit_equal_qobject(&helper->objs[helper->index++], obj);
>  }
>  
> +static bool qlit_equal_qdict(const QLitObject *lhs, const QDict *qdict)
> +{
> +    int i;
> +
> +    for (i = 0; lhs->value.qdict[i].key; i++) {
> +        QObject *obj = qdict_get(qdict, lhs->value.qdict[i].key);
> +
> +        if (!qlit_equal_qobject(&lhs->value.qdict[i].value, obj)) {
> +            return false;
> +        }
> +    }
> +
> +    /* Note: the literal qdict must not contain duplicates, this is
> +     * considered a programming error and it isn't checked here. */
> +    if (qdict_size(qdict) != i) {
> +        return false;
> +    }
> +
> +    return true;
> +}
> +
>  bool qlit_equal_qobject(const QLitObject *lhs, const QObject *rhs)
>  {
>      if (!rhs || lhs->type != qobject_type(rhs)) {
> @@ -55,20 +76,8 @@ bool qlit_equal_qobject(const QLitObject *lhs, const QObject *rhs)
>      case QTYPE_QSTRING:
>          return (strcmp(lhs->value.qstr,
>                         qstring_get_str(qobject_to_qstring(rhs))) == 0);
> -    case QTYPE_QDICT: {
> -        int i;
> -
> -        for (i = 0; lhs->value.qdict[i].key; i++) {
> -            QObject *obj = qdict_get(qobject_to_qdict(rhs),
> -                                     lhs->value.qdict[i].key);
> -
> -            if (!qlit_equal_qobject(&lhs->value.qdict[i].value, obj)) {
> -                return false;
> -            }
> -        }
> -
> -        return true;
> -    }
> +    case QTYPE_QDICT:
> +        return qlit_equal_qdict(lhs, qobject_to_qdict(rhs));
>      case QTYPE_QLIST: {
>          QListCompareHelper helper;
>  
> diff --git a/tests/check-qlit.c b/tests/check-qlit.c
> index 47fde92a46..5d9558dfd9 100644
> --- a/tests/check-qlit.c
> +++ b/tests/check-qlit.c
> @@ -28,6 +28,11 @@ static QLitObject qlit = QLIT_QDICT(((QLitDictEntry[]) {
>      { },
>  }));
>  
> +static QLitObject qlit_foo = QLIT_QDICT(((QLitDictEntry[]) {
> +    { "foo", QLIT_QNUM(42) },
> +    { },
> +}));
> +
>  static QObject *make_qobject(void)
>  {
>      QDict *qdict = qdict_new();
> @@ -51,6 +56,8 @@ static void qlit_equal_qobject_test(void)
>  
>      g_assert(qlit_equal_qobject(&qlit, qobj));
>  
> +    g_assert(!qlit_equal_qobject(&qlit_foo, qobj));
> +
>      qobject_decref(qobj);
>  }

Ah, you do have negative test cases, just not in the patch creating the
test.

When you leave gaps in that will be filled in later patches, I recomend
pointing out the gaps in the commit message, with a promise they'll be
filled shortly.  Your reviewers will thank you.

With am improved commit message,
Reviewed-by: Markus Armbruster <armbru@redhat.com>