[PATCH] D50580: [clang-tidy] Abseil: no namespace check

[Jonas Toth via Phabricator via cfe-commits]

JonasToth added inline comments.


================
Comment at: clang-tidy/abseil/NoNamespaceCheck.cpp:23
+
+  Finder->addMatcher(namespaceDecl(hasName("absl")).bind("absl_namespace"),
+                     this);
----------------
hugoeg wrote:
> deannagarcia wrote:
> > aaron.ballman wrote:
> > > hokein wrote:
> > > > aaron.ballman wrote:
> > > > > I think this needs a `not(isExpansionInSystemHeader())` in there, as this is going to trigger on code that includes a header file using an `absl` namespace. If I'm incorrect and users typically include abseil as something other than system includes, you'll have to find a different way to solve this.
> > > > Yeah, we have discussed this issue internally.  abseil-user code usually includes abseil header like `#include "whatever/abseil/base/optimization.h"`, so `IsExpansionInSystemHeader` doesn't work for most cases. 
> > > > 
> > > > We need a way to filter out all headers being a part of abseil library. I think we can create a matcher `InExpansionInAbseilHeader` -- basically using `IsExpansionInFileMatching` with a regex expression that matches typical abseil include path. What do you think?
> > > > 
> > > > And we'll have more abseil checks (e.g.  `abseil-no-internal-deps`) that use `InExpansionInAbseilHeader`, we should put it to a common header.
> > > I think that is a sensible approach.
> > We will begin working on this, I think it will first be implemented in abseil-no-internal-deps but once it looks good I will add it to this patch.
> I'm going to go ahead a implement this in ASTMatchers.h and include it on the patch for **abseil-no-internal-dep**s
In principle it is ok, but I don't think ASTMatchers.h is the correct place, because it is only of use to clang-tidy.

There is a `util` directory in clang-tidy for this kind of stuff. Defining you own matchers works the same as in ASTMatchers, you can grep through clang-tidy checks (e.g. `AST_MATCHER`) to have some examples of private matchers.


https://reviews.llvm.org/D50580