[cfe-commits] [PATCH]: Matchers for ignoring paren/implicit casts

[Sam Panzer]

On Mon, Aug 13, 2012 at 1:57 AM, Manuel Klimek <klimek at google.com> wrote:

>
> On Thu, Aug 2, 2012 at 7:48 PM, Sam Panzer <panzer at google.com> wrote:
> > Here you go.
>
> Sorry for not getting to this earlier - apparently nobody has
> submitted this yet :)
>

No problem :)


> I'm happy to submit it, but patch complains about the patch - is there
> a reason there are no newlines after the @@ ... @@ parts?
>

That's odd...I must have deleted a spare newline in that section. Here's
another diff that I successfully patched onto master.


>
> Cheers,
> /Manuel
>
> >
> >
> > On Thu, Aug 2, 2012 at 7:04 AM, Manuel Klimek <klimek at google.com> wrote:
> >>
> >>
> >> A couple more things:
> >> - please completely take out the type() matcher - I've looked into it,
> >> and we need to come up with a good design here first; until then I
> >> don't think it makes sense to have a hack in
> >> - please rename castExpression -> castExpr to be consistent with the
> node
> >> name
> >>
> >> Apart from that lgtm
> >>
> >> Cheers,
> >> /Manuel
> >>
> >> On Mon, Jul 30, 2012 at 7:49 PM, Sam Panzer <panzer at google.com> wrote:
> >> >
> >> > A new version, with shorter (Implicit --> Imp) matcher names!
> >> >
> >> > On Mon, Jul 30, 2012 at 5:32 AM, Manuel Klimek <klimek at google.com>
> >> > wrote:
> >> >>
> >> >>
> >> >> On Thu, Jul 26, 2012 at 11:15 PM, Sam Panzer <panzer at google.com>
> wrote:
> >> >> >
> >> >> > Here's the next version!
> >> >> >
> >> >> > On Thu, Jul 26, 2012 at 1:53 AM, Manuel Klimek <klimek at google.com>
> >> >> > wrote:
> >> >> >>
> >> >> >>
> >> >> >> +/// \brief Matches expressions that match InnerMatcher after
> >> >> >> parentheses
> >> >> >> and
> >> >> >> +/// casts are stripped off.
> >> >> >> +///
> >> >> >> +/// Implicit and non-C Style casts are not discarded.
> >> >> >>
> >> >> >> This contradicts the example...
> >> >> >
> >> >> >
> >> >> > s/not/also/
> >> >> > Though I'm not sure if this makes it any clearer than not having a
> >> >> > comment.
> >> >> >
> >> >> >>
> >> >> >>
> >> >> >> +/// \brief Matches any cast nodes of Clang's AST.
> >> >> >> +///
> >> >> >> +/// Example: castExpression() matches each of the following:
> >> >> >> +///   (int) 3;
> >> >> >> +///   const_cast<Expr *>(SubExpr);
> >> >> >> +///   (i);
> >> >> >> +///   char c = 0;
> >> >> >> +const internal::VariadicDynCastAllOfMatcher<
> >> >> >> +  Expr,
> >> >> >> +  CastExpr> castExpression;
> >> >> >
> >> >> >
> >> >> > Actually, this comment wasn't correct either, since parentheses
> >> >> > aren't
> >> >> > CastExpr's. Fixed!
> >> >> >
> >> >> >>
> >> >> >>
> >> >> >> I'd vote for calling all new matchers we write exactly like the
> AST
> >> >> >> nodes (castExpr in this case).
> >> >> >> I lost the fight, and if we ever want to get to the place where it
> >> >> >> all
> >> >> >> just works, we have to start not introducing new violations of
> that
> >> >> >> rule.
> >> >> >> Same for Implicit -> Imp (it hurts me, but, oh well, I'll live ;)
> >> >> >
> >> >> >
> >> >> > I would agree on the AST-style naming convention. I can see three
> >> >> > naming
> >> >> > styles for CastExpr among existing matchers: cast (already taken!),
> >> >> > castExpression (what I used), and castExpr.  Which cast matchers
> are
> >> >> > you
> >> >> > suggesting should be renamed, and to what? I'll be happy to change
> >> >> > them,
> >> >> > but
> >> >> > I'm not sure what you're asking.
> >> >>
> >> >> ignoringImplicitCasts -> ignoringImpCasts
> >> >> ignoringParenImplicitCasts -> ingoringParenImpCasts
> >> >
> >> >
> >> > Done.
> >> >
> >> >>
> >> >>
> >> >> >> +  EXPECT_TRUE(matches("char *p = reinterpret_cast<char *>(&p);",
> >> >> >> +                      expression(castExpression())));
> >> >> >>
> >> >> >> Btw, if we defined the castExpr as
> VariadicDynCastAllOfMatcher<Stmt,
> >> >> >> CastExpr> just putting them in top-level would work, too. Since a
> >> >> >> Matcher<Stmt> is-a Matcher<Expr> this would also not limit the use
> >> >> >> of
> >> >> >> castExpr.
> >> >> >>
> >> >> >
> >> >> > I was following the other cast examples such as implicitCast. Would
> >> >> > it
> >> >> > be
> >> >> > better to change this?
> >> >>
> >> >> Yes, and I think we should change the others, but not in this CL;
> just
> >> >> use
> >> >> const internal::VariadicDynCastAllOfMatcher<Stmt, CastExpr>
> >> >> castExpression;
> >> >>
> >> >> >
> >> >> >>
> >> >> >> +                          pointsTo(TypeMatcher(anything())))))));
> >> >> >>
> >> >> >> This is unfortunate. We should add a type() matcher.
> >> >> >
> >> >> >
> >> >> > I've used this workaround in my client code - and I just discovered
> >> >> > that
> >> >> > the
> >> >> > test Matcher.HandlesNullQualTypes does too (with a fixme echoing
> your
> >> >> > complaint):
> >> >> >   const TypeMatcher AnyType = anything();
> >> >> >
> >> >> > I briefly tried adding a type() matcher, but it seems like matchers
> >> >> > treat
> >> >> > types differently from statements and declarations. All existing
> >> >> > matchers on
> >> >> > types just take a single argument, which is usually
> hasDeclaration()
> >> >> > in
> >> >> > some
> >> >> > form (often indirectly), so it's not as easy as adding another
> >> >> > AST_MATCHER
> >> >> > definition. I'll leave this up to someone who really knows how the
> >> >> > new
> >> >> > matcher should fit in :)
> >> >>
> >> >> A type matcher would be added like this:
> >> >> const internal::VariadicDynCastAllOfMatcher<QualType, QualtType>
> type;
> >> >
> >> >
> >> > I tried that already. It fails because QualType does not define the
> >> > member
> >> > functions needed for dyn_cast to work, i.e. classOf(). I'm not brave
> >> > enough
> >> > to try modifying QualType directly just for a type matcher, nor am I
> >> > sure
> >> > that it's the right fix.
> >> >
> >> >>
> >> >>
> >> >> >> +TEST(CastExpression, MatchesSimpleCases) {
> >> >> >>
> >> >> >> I'm not really happy with those names, but I'm aware it's really
> >> >> >> hard
> >> >> >> to come up with good test names in those cases.
> >> >> >
> >> >> >
> >> >> > I broke the test into MatchesImplicitCasts and
> MatchesExplicitCasts,
> >> >> > both of
> >> >> > which are much better names.
> >> >> >
> >> >> >
> >> >> >
> >> >
> >> >
> >
> >
>
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