Bring the return value of SmallVector::insert in line with std::vector::insert.

It always returns the iterator for the first inserted element, or the passed in
iterator if the inserted range was empty. Flesh out the unit test more and fix
all the cases it uncovered so far.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158645 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/ADT/SmallVector.h b/include/llvm/ADT/SmallVector.h
index 02eee622900a8d1112eadee3426405e8f83e4c43..2d71249c52c5ea0da48c2653fe71efdba0a9abbf 100644 (file)
--- a/include/llvm/ADT/SmallVector.h
+++ b/include/llvm/ADT/SmallVector.h
@@ -540,14 +540,14 @@ public:
   }
 
   iterator insert(iterator I, size_type NumToInsert, const T &Elt) {
+    // Convert iterator to elt# to avoid invalidating iterator when we reserve()
+    size_t InsertElt = I - this->begin();
+
     if (I == this->end()) {  // Important special case for empty vector.
       append(NumToInsert, Elt);
-      return NumToInsert == 0 ? this->end() : this->end()-1;
+      return this->begin()+InsertElt;
     }
 
-    // Convert iterator to elt# to avoid invalidating iterator when we reserve()
-    size_t InsertElt = I - this->begin();
-
     // Ensure there is enough space.
     reserve(static_cast<unsigned>(this->size() + NumToInsert));
 
@@ -588,14 +588,15 @@ public:
 
   template<typename ItTy>
   iterator insert(iterator I, ItTy From, ItTy To) {
+    // Convert iterator to elt# to avoid invalidating iterator when we reserve()
+    size_t InsertElt = I - this->begin();
+
     if (I == this->end()) {  // Important special case for empty vector.
       append(From, To);
-      return From == To ? this->end() : this->end()-1;
+      return this->begin()+InsertElt;
     }
 
     size_t NumToInsert = std::distance(From, To);
-    // Convert iterator to elt# to avoid invalidating iterator when we reserve()
-    size_t InsertElt = I - this->begin();
 
     // Ensure there is enough space.
     reserve(static_cast<unsigned>(this->size() + NumToInsert));
@@ -628,9 +629,9 @@ public:
     this->uninitialized_copy(I, OldEnd, this->end()-NumOverwritten);
 
     // Replace the overwritten part.
-    for (; NumOverwritten > 0; --NumOverwritten) {
-      *I = *From;
-      ++I; ++From;
+    for (T *J = I; NumOverwritten > 0; --NumOverwritten) {
+      *J = *From;
+      ++J; ++From;
     }
 
     // Insert the non-overwritten middle part.

diff --git a/unittests/ADT/SmallVectorTest.cpp b/unittests/ADT/SmallVectorTest.cpp
index 8f6d2f4ac1509054489b8222dc70c8cf887b0516..d35e5bc08a274bd24bb82a1d0e21937cc699296a 100644 (file)
--- a/unittests/ADT/SmallVectorTest.cpp
+++ b/unittests/ADT/SmallVectorTest.cpp
@@ -342,7 +342,9 @@ TEST_F(SmallVectorTest, InsertTest) {
   SCOPED_TRACE("InsertTest");
 
   makeSequence(theVector, 1, 3);
-  theVector.insert(theVector.begin() + 1, Constructable(77));
+  VectorType::iterator I =
+    theVector.insert(theVector.begin() + 1, Constructable(77));
+  EXPECT_EQ(theVector.begin() + 1, I);
   assertValuesInOrder(theVector, 4u, 1, 77, 2, 3);
 }
 
@@ -351,24 +353,48 @@ TEST_F(SmallVectorTest, InsertRepeatedTest) {
   SCOPED_TRACE("InsertRepeatedTest");
 
   makeSequence(theVector, 10, 15);
-  theVector.insert(theVector.begin() + 1, 2, Constructable(16));
+  VectorType::iterator I =
+    theVector.insert(theVector.begin() + 1, 2, Constructable(16));
+  EXPECT_EQ(theVector.begin() + 1, I);
   assertValuesInOrder(theVector, 8u, 10, 16, 16, 11, 12, 13, 14, 15);
 
+  // Insert at end.
+  I = theVector.insert(theVector.end(), 2, Constructable(16));
+  EXPECT_EQ(theVector.begin() + 8, I);
+  assertValuesInOrder(theVector, 10u, 10, 16, 16, 11, 12, 13, 14, 15, 16, 16);
+
+  // Empty insert.
   EXPECT_EQ(theVector.end(),
             theVector.insert(theVector.end(), 0, Constructable(42)));
+  EXPECT_EQ(theVector.begin() + 1,
+            theVector.insert(theVector.begin() + 1, 0, Constructable(42)));
 }
 
 // Insert range.
 TEST_F(SmallVectorTest, InsertRangeTest) {
-  SCOPED_TRACE("InsertRepeatedTest");
+  SCOPED_TRACE("InsertRangeTest");
+
+  Constructable Arr[3] =
+    { Constructable(77), Constructable(77), Constructable(77) };
 
   makeSequence(theVector, 1, 3);
-  theVector.insert(theVector.begin() + 1, 3, Constructable(77));
+  VectorType::iterator I =
+    theVector.insert(theVector.begin() + 1, Arr, Arr+3);
+  EXPECT_EQ(theVector.begin() + 1, I);
   assertValuesInOrder(theVector, 6u, 1, 77, 77, 77, 2, 3);
 
+  // Insert at end.
+  I = theVector.insert(theVector.end(), Arr, Arr+3);
+  EXPECT_EQ(theVector.begin() + 6, I);
+  assertValuesInOrder(theVector, 9u, 1, 77, 77, 77, 2, 3, 77, 77, 77);
+
+  // Empty insert.
   EXPECT_EQ(theVector.end(), theVector.insert(theVector.end(),
                                               theVector.begin(),
                                               theVector.begin()));
+  EXPECT_EQ(theVector.begin() + 1, theVector.insert(theVector.begin() + 1,
+                                                    theVector.begin(),
+                                                    theVector.begin()));
 }
 
 // Comparison tests.