any C/C++ refactoring tool based on libclang? (even simplest “toy example” ) [closed]

Answer 1

Google have been working on a tooling library for Clang. In since the 3.2 release. It includes a ASTMatchers library so you can just build up a query and don't have to walk the AST.

There is a great video talk on the subject that walks through a simple rename example. (This is from the same guy as the MapReduce talk posted above but is newer and more about a simple practical implementation rather than the internal design and enterprise scale stuff Google have going on).

The source for that example that renames a method is available in the tooling branch. It may be somewhere in the trunk but I can't find it. Also Rename the getDeclAs function to getNodesAs as the other is apparently deprecated.). There is a more advanced example that removes duplicated c_str calls (which is in trunk and someone posted above).

Here is documentation for LibASTMatchers and LibTooling.

EDIT: Some better docs for ASTMatcher. Here and here.

EDIT: Google are now working on something called Clangd which aims to be some kind of Clang server for refactoring.

Answer 2

Not open source, but has been used to carry out very non-toy massive automated refactoring of C++ programs: our DMS Software Reengineering Toolkit. DMS is a "library" (we called it a "toolkit") of facilities on can compose to achieve anlaysis and/or automated translation.

Relevant to C++, DMS provides at this point in time:

• Full C++11 parser, constructing the AST and able to regenerate source code accurately including comments, with a complete preprocessor
• Full C++ parser with name and type resolution for C++ (ANSI, GNU, MS Visual C++)
• Control flow analysis for C++
• Source-to-source transformations
• Partially complete "rename" machinery (see discussion below)

What I can say from experience is that C++ is a bitch of a language to transform.

We continue to work on it, and are completing a reliable renaming tool. Even this is hard; a key problem is the name-shadowing problem. You have a local variable X, and a reference to Y inside that scope; you attempt to rename Y to X and discover that the local variable "captures" the access. It is amazing how many namespaces and capture types you have to worry about in C++. And this is needed as a foundation for many other refactorings.

EDIT Feb 2014: Full C++14 parser, control flow analysis, local data flow analysis