ADT: Use 'using' to inherit assign and append in SmallString

Rather than reimplement, use a `using` declaration to bring in
`SmallVectorImpl<char>`'s assign and append implementations in
`SmallString`.

The `SmallString` versions were missing reference invalidation
assertions from `SmallVector`. This patch also fixes a bug in
`llvm::FileCollector::addFileImpl`, which was a copy/paste from
`clang::ModuleDependencyCollector::copyToRoot`, both caught by the
no-longer-skipped assertions.

As a drive-by, this also sinks the `const SmallVectorImpl&` versions of
these methods down into `SmallVectorImpl`, since I imagine they'd be
useful elsewhere.

Differential Revision: https://reviews.llvm.org/D95202

1 files changed, 18 insertions, 0 deletions

diff --git a/llvm/unittests/ADT/SmallVectorTest.cpp b/llvm/unittests/ADT/SmallVectorTest.cpp
index b2cccc1..a533bb8 100644
--- a/llvm/unittests/ADT/SmallVectorTest.cpp
+++ b/llvm/unittests/ADT/SmallVectorTest.cpp
@@ -485,6 +485,15 @@ TYPED_TEST(SmallVectorTest, AppendRepeatedNonForwardIterator) {
   this->assertValuesInOrder(this->theVector, 3u, 1, 7, 7);
 }
 
+TYPED_TEST(SmallVectorTest, AppendSmallVector) {
+  SCOPED_TRACE("AppendSmallVector");
+
+  SmallVector<Constructable, 3> otherVector = {7, 7};
+  this->theVector.push_back(Constructable(1));
+  this->theVector.append(otherVector);
+  this->assertValuesInOrder(this->theVector, 3u, 1, 7, 7);
+}
+
 // Assign test
 TYPED_TEST(SmallVectorTest, AssignTest) {
   SCOPED_TRACE("AssignTest");
@@ -513,6 +522,15 @@ TYPED_TEST(SmallVectorTest, AssignNonIterTest) {
   this->assertValuesInOrder(this->theVector, 2u, 7, 7);
 }
 
+TYPED_TEST(SmallVectorTest, AssignSmallVector) {
+  SCOPED_TRACE("AssignSmallVector");
+
+  SmallVector<Constructable, 3> otherVector = {7, 7};
+  this->theVector.push_back(Constructable(1));
+  this->theVector.assign(otherVector);
+  this->assertValuesInOrder(this->theVector, 2u, 7, 7);
+}
+
 // Move-assign test
 TYPED_TEST(SmallVectorTest, MoveAssignTest) {
   SCOPED_TRACE("MoveAssignTest");