How find BlockDecl nodes in Clang AST using AST Matcher?

Question

I need to find self references in blocks (Objective C). And I'm using Clang AST Matchers for this.

The matcher to find all self references I've created is below:

declRefExpr(to(varDecl(hasName("self")))

Now I need to apply this matcher for blocks only. But I can't find how to do it. Does anyone have any ideas?

Answer 1

I've resolved the question by the following matcher (in OCLint):

virtual void setUpMatcher() override
{
    StatementMatcher blockExpression = expr(hasType(blockPointerType()));

    addMatcher(declRefExpr(to(varDecl(hasName("self"))), hasAncestor(blockExpression)).bind("selfRefInBlock"));

}

Ultimately I resolved to find BlockExpr instead of BlockDecl. So, the rule above finds self references in all block expressions. But I didn't realize that in some blocks self is valid. For example the block within dispatch_once which executes a block object once and only once for the lifetime of an application.

dispatch_once(&onceToken, ^{
        sharedInstance = [[self alloc] init];
    });

Therefore I think I need to find BlockDecl again :)