[libTooling] Add `ifBound`, `elseBranch` RangeSelector combinators.

Summary:
Adds two new combinators and corresponding tests to the RangeSelector library.
* `ifBound` -- conditional evaluation of range-selectors, based on whether a
   given node id is bound in the match.
* `elseBranch` -- selects the source range of the else and its statement.

Reviewers: gribozavr

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D67621

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@372410 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 9 insertions, 0 deletions

diff --git a/include/clang/Tooling/Refactoring/RangeSelector.h b/include/clang/Tooling/Refactoring/RangeSelector.h
index b117e4d82a..e5fe051413 100644
--- a/include/clang/Tooling/Refactoring/RangeSelector.h
+++ b/include/clang/Tooling/Refactoring/RangeSelector.h
@@ -79,10 +79,19 @@ RangeSelector statements(std::string ID);
 // (all source between the braces).
 RangeSelector initListElements(std::string ID);
 
+/// Given an \IfStmt (bound to \p ID), selects the range of the else branch,
+/// starting from the \c else keyword.
+RangeSelector elseBranch(std::string ID);
+
 /// Selects the range from which `S` was expanded (possibly along with other
 /// source), if `S` is an expansion, and `S` itself, otherwise.  Corresponds to
 /// `SourceManager::getExpansionRange`.
 RangeSelector expansion(RangeSelector S);
+
+/// Chooses between the two selectors, based on whether \p ID is bound in the
+/// match.
+RangeSelector ifBound(std::string ID, RangeSelector TrueSelector,
+                      RangeSelector FalseSelector);
 } // namespace tooling
 } // namespace clang