BLI: improve various C++ data structures

The changes come from the `functions` branch, where I'm using
these structures a lot.

This also includes a new `BLI::Optional<T>` type, which is similar
to `std::Optional<T>` which can be used when Blender starts using
C++17.

1 files changed, 13 insertions, 2 deletions

diff --git a/tests/gtests/blenlib/BLI_stack_cxx_test.cc b/tests/gtests/blenlib/BLI_stack_cxx_test.cc
index 436f1f307b9..272bba05cb8 100644
--- a/tests/gtests/blenlib/BLI_stack_cxx_test.cc
+++ b/tests/gtests/blenlib/BLI_stack_cxx_test.cc
@@ -8,7 +8,7 @@ TEST(stack, DefaultConstructor)
 {
   IntStack stack;
   EXPECT_EQ(stack.size(), 0);
-  EXPECT_TRUE(stack.empty());
+  EXPECT_TRUE(stack.is_empty());
 }
 
 TEST(stack, ArrayRefConstructor)
@@ -19,7 +19,7 @@ TEST(stack, ArrayRefConstructor)
   EXPECT_EQ(stack.pop(), 2);
   EXPECT_EQ(stack.pop(), 7);
   EXPECT_EQ(stack.pop(), 4);
-  EXPECT_TRUE(stack.empty());
+  EXPECT_TRUE(stack.is_empty());
 }
 
 TEST(stack, Push)
@@ -32,6 +32,17 @@ TEST(stack, Push)
   EXPECT_EQ(stack.size(), 2);
 }
 
+TEST(stack, PushMultiple)
+{
+  IntStack stack;
+  EXPECT_EQ(stack.size(), 0);
+  stack.push_multiple({1, 2, 3});
+  EXPECT_EQ(stack.size(), 3);
+  EXPECT_EQ(stack.pop(), 3);
+  EXPECT_EQ(stack.pop(), 2);
+  EXPECT_EQ(stack.pop(), 1);
+}
+
 TEST(stack, Pop)
 {
   IntStack stack;