Add a Visit overload for DynTypedNode to ASTNodeTraverser

[steveire]

Format

[aaron.ballman]

What will be making use of/testing this new functionality?

[steveire]

In D61834#1504665, @aaron.ballman wrote:

What will be making use of/testing this new functionality?

Any code which has a DynTypedNode and wishes to traverse it.

I envisage this as a more-flexible DynTypedNode::dump that the user does not have to implement themselves in order to use the ASTNodeTraverser.

[aaron.ballman]

In D61834#1505056, @steveire wrote:

In D61834#1504665, @aaron.ballman wrote:

What will be making use of/testing this new functionality?

Any code which has a DynTypedNode and wishes to traverse it.

I envisage this as a more-flexible DynTypedNode::dump that the user does not have to implement themselves in order to use the ASTNodeTraverser.

Do we currently have any such code that's using this functionality, though? I'm mostly concerned that this is dead code with no testing, currently. The functionality itself seems reasonable enough and the code looks correct enough, so if this is part of a series of planned changes, that'd be good information to have for the review.

[steveire]

In D61834#1505124, @aaron.ballman wrote:

In D61834#1505056, @steveire wrote:

In D61834#1504665, @aaron.ballman wrote:

What will be making use of/testing this new functionality?

Any code which has a DynTypedNode and wishes to traverse it.

I envisage this as a more-flexible DynTypedNode::dump that the user does not have to implement themselves in order to use the ASTNodeTraverser.

Do we currently have any such code that's using this functionality, though? I'm mostly concerned that this is dead code with no testing, currently. The functionality itself seems reasonable enough and the code looks correct enough, so if this is part of a series of planned changes, that'd be good information to have for the review.

Ah, yes. This is supposed to be 'useful public API' like the other Visit methods for use inside and outside the codebase. A follow-up patch will use it, but it's provided for external use too anyway.

I'll add a unit test.

[steveire]

Add basic traverser test

[steveire]

Update

[aaron.ballman]

In D61834#1505418, @steveire wrote:

In D61834#1505124, @aaron.ballman wrote:

In D61834#1505056, @steveire wrote:

In D61834#1504665, @aaron.ballman wrote:

What will be making use of/testing this new functionality?

Any code which has a DynTypedNode and wishes to traverse it.

I envisage this as a more-flexible DynTypedNode::dump that the user does not have to implement themselves in order to use the ASTNodeTraverser.

Do we currently have any such code that's using this functionality, though? I'm mostly concerned that this is dead code with no testing, currently. The functionality itself seems reasonable enough and the code looks correct enough, so if this is part of a series of planned changes, that'd be good information to have for the review.

Ah, yes. This is supposed to be 'useful public API' like the other Visit methods for use inside and outside the codebase. A follow-up patch will use it, but it's provided for external use too anyway.

I'll add a unit test.

Ahh, thank you! It makes a lot more sense to me now. LGTM aside from some nits.

include/clang/AST/ASTNodeTraverser.h

208

Can you add a comment here: // FIXME: Improve this with a switch or a visitor pattern. (We have a similar comment in similar-looking code in ASTMatchFinder.cpp:476.)

unittests/AST/ASTTraverserTest.cpp

75 ↗

(On Diff #199992)

Did clang-format produce this formatting? (If not, run through clang-format.)

89 ↗

(On Diff #199992)

Name instead

97 ↗

(On Diff #199992)

DumpString -- same elsewhere.

[steveire]

unittests/AST/ASTTraverserTest.cpp

75 ↗

(On Diff #199992)

Yep, clang-format made it like this.

[aaron.ballman]

unittests/AST/ASTTraverserTest.cpp

75 ↗

(On Diff #199992)

Weird that it added the extra whitespace -- I think this is the only instance where we have whitespace to either side of the adornments, which is what caught me by surprise.

include/clang/AST/ASTNodeTraverser.h

getNodeDelegate().AddChild([=] {
                                                                           FC);
       for (comments::Comment::child_iterator I = C->child_begin(),
                                              E = C->child_end();
            I != E; ++I)
         Visit(*I, FC);
     });
   }
 
+  void Visit(const ast_type_traits::DynTypedNode &N) {
+    if (const auto *D = N.get<Decl>())
+      Visit(D);
+    else if (const auto *S = N.get<Stmt>())
+      Visit(S);
+    else if (const auto *QT = N.get<QualType>())
+      Visit(*QT);
+    else if (const auto *T = N.get<Type>())
+      Visit(T);
+    else if (const auto *A = N.get<Attr>())
+      Visit(A);
+    else if (const auto *C = N.get<CXXCtorInitializer>())
+      Visit(C);
+    else if (const auto *C = N.get<OMPClause>())
+      Visit(C);
+    else if (const auto *C = N.get<comments::FullComment>())
+      Visit(C, C);
+    else if (const auto *T = N.get<TemplateArgument>())
+      Visit(*T);
+  }
+
   void dumpDeclContext(const DeclContext *DC) {
     if (!DC)
       return;
 
     for (const auto *D : (Deserialize ? DC->decls() : DC->noload_decls()))
       Visit(D);
   }