Export of internal Abseil changes

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30af50146f07d7afdb196abf235f44ec44ea6409 by Derek Mauro <dmauro@google.com>:

Update Abseil dependency versions

PiperOrigin-RevId: 374415690

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6a241e9ea8ee201789bb66aadf9e1ca9cc23c5dc by Derek Mauro <dmauro@google.com>:

Fix the install test project, which is doing a mixed-mode build.
This manifests in failure with GCC 11, which defaults to C++17

Also explicitly reference python3 in the test script.
python2 is being removed by some Linux distros.

PiperOrigin-RevId: 374278107

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42f85122407e799183880e0b2e2a71f6d35ee003 by Evan Brown <ezb@google.com>:

Use `capacity + Group::kWidth` control bytes instead of `capacity + Group::kWidth + 1`.

We don't use the extra byte - we only need the first `capacity` ones that are valid, the one sentinel byte and then `Group::kWidth - 1` cloned control bytes. For example, in `EmptyGroup()`, where capacity is 0, we use `Group::kWidth` control bytes.

We need to update set_ctrl() to only mirror `Group::kWidth - 1` bytes instead of `Group::kWidth` bytes.

Note: this doesn't actually save memory unless `alignof(value_type)` is one.

Also add/update related comments.

PiperOrigin-RevId: 374198589

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5dcd09b2221bf23add583541769b476dac54e112 by Evan Brown <ezb@google.com>:

Improve b-tree value_comp() support.

- Don't expose internal adapted comparator functionality.
- Support value_comp() for maps using function pointer comparators.
- For maps, make value_compare's constructor and the member comparator be protected - [reference](https://en.cppreference.com/w/cpp/container/map/value_compare).

PiperOrigin-RevId: 373832649

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d75819786ff5a06e1ed0c5c1e80b3b95ac49c83b by Evan Brown <ezb@google.com>:

Don't export adapted comparator functionality in key_comp().

PiperOrigin-RevId: 373651039
GitOrigin-RevId: 30af50146f07d7afdb196abf235f44ec44ea6409
Change-Id: I260480b0923cefeba81c543e2b7c34cacaa7d7c7

1 files changed, 26 insertions, 12 deletions

diff --git a/absl/container/btree_test.cc b/absl/container/btree_test.cc
index 464dabac..d5d79151 100644
--- a/absl/container/btree_test.cc
+++ b/absl/container/btree_test.cc
@@ -1708,10 +1708,25 @@ TEST(Btree, StrSplitCompatible) {
   EXPECT_EQ(split_set, expected_set);
 }
 
-// We can't use EXPECT_EQ/etc. to compare absl::weak_ordering because they
-// convert literal 0 to int and absl::weak_ordering can only be compared with
-// literal 0. Defining this function allows for avoiding ClangTidy warnings.
-bool Identity(const bool b) { return b; }
+TEST(Btree, KeyComp) {
+  absl::btree_set<int> s;
+  EXPECT_TRUE(s.key_comp()(1, 2));
+  EXPECT_FALSE(s.key_comp()(2, 2));
+  EXPECT_FALSE(s.key_comp()(2, 1));
+
+  absl::btree_map<int, int> m1;
+  EXPECT_TRUE(m1.key_comp()(1, 2));
+  EXPECT_FALSE(m1.key_comp()(2, 2));
+  EXPECT_FALSE(m1.key_comp()(2, 1));
+
+  // Even though we internally adapt the comparator of `m2` to be three-way and
+  // heterogeneous, the comparator we expose through key_comp() is the original
+  // unadapted comparator.
+  absl::btree_map<std::string, int> m2;
+  EXPECT_TRUE(m2.key_comp()("a", "b"));
+  EXPECT_FALSE(m2.key_comp()("b", "b"));
+  EXPECT_FALSE(m2.key_comp()("b", "a"));
+}
 
 TEST(Btree, ValueComp) {
   absl::btree_set<int> s;
@@ -1724,13 +1739,13 @@ TEST(Btree, ValueComp) {
   EXPECT_FALSE(m1.value_comp()(std::make_pair(2, 0), std::make_pair(2, 0)));
   EXPECT_FALSE(m1.value_comp()(std::make_pair(2, 0), std::make_pair(1, 0)));
 
+  // Even though we internally adapt the comparator of `m2` to be three-way and
+  // heterogeneous, the comparator we expose through value_comp() is based on
+  // the original unadapted comparator.
   absl::btree_map<std::string, int> m2;
-  EXPECT_TRUE(Identity(
-      m2.value_comp()(std::make_pair("a", 0), std::make_pair("b", 0)) < 0));
-  EXPECT_TRUE(Identity(
-      m2.value_comp()(std::make_pair("b", 0), std::make_pair("b", 0)) == 0));
-  EXPECT_TRUE(Identity(
-      m2.value_comp()(std::make_pair("b", 0), std::make_pair("a", 0)) > 0));
+  EXPECT_TRUE(m2.value_comp()(std::make_pair("a", 0), std::make_pair("b", 0)));
+  EXPECT_FALSE(m2.value_comp()(std::make_pair("b", 0), std::make_pair("b", 0)));
+  EXPECT_FALSE(m2.value_comp()(std::make_pair("b", 0), std::make_pair("a", 0)));
 }
 
 TEST(Btree, DefaultConstruction) {
@@ -2906,8 +2921,7 @@ TEST(Btree, SupportsFunctionPtrComparator) {
   map[1] = 1;
   EXPECT_THAT(map, ElementsAre(Pair(1, 1)));
   EXPECT_TRUE(map.key_comp()(1, 2));
-  // TODO(ezb): support value_comp() in this case and uncomment.
-  // EXPECT_TRUE(map.value_comp()(std::make_pair(1, 1), std::make_pair(2, 2)));
+  EXPECT_TRUE(map.value_comp()(std::make_pair(1, 1), std::make_pair(2, 2)));
 }
 
 template <typename Compare>