Export of internal Abseil changes.

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78293ba4eb4981991ae7e6edd25eb9245fcd7515 by Andy Soffer <asoffer@google.com>:

internal changes

PiperOrigin-RevId: 247073879

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7bd97e3aad0c3012b89a39392a6ad3f254e9f3c3 by Derek Mauro <dmauro@google.com>:

Release commandline flags

PiperOrigin-RevId: 247065920

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2a991849fd7b140a43b073076d194b61533fd199 by Tom Manshreck <shreck@google.com>:

Add documentation for built-in usage flags

PiperOrigin-RevId: 247058863

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14157b0de45841706bbd631284191fd94c313db9 by Derek Mauro <dmauro@google.com>:

Internal change

PiperOrigin-RevId: 247058292

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ed67e0a80468596e30540b367727a250fa415b68 by Abseil Team <absl-team@google.com>:

Internal Change.

PiperOrigin-RevId: 246828655

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e1bc8c2aa3f90b3d56c55c5b7244e718c919265d by Abseil Team <absl-team@google.com>:

Internal change

PiperOrigin-RevId: 246822325

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907a68f287199f749cb9bdb48571b50bc34731e1 by Eric Fiselier <ericwf@google.com>:

Accept vector<bool>::reference in StrCat and friends.

Converting vector<bool>::reference to alphanum requires
two user defined conversions, which isn't allowed.
In order to accept this, we need a special constructor that
is only enabled for the bool proxy types.

PiperOrigin-RevId: 246626732

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fe4295fa95cc65dee8c881ba12dd8f516e68c40d by Abseil Team <absl-team@google.com>:

Clarify the proper way to define AbslHashValue, and fix confusing indentation.

PiperOrigin-RevId: 246406528

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d7174681a72d4a25c8fd2b4d9f515a0763eff87c by Gennadiy Rozental <rogeeff@google.com>:

Internal change

PiperOrigin-RevId: 246358214

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a7fdc19683cf1a5885e9e1af52fcdb2db1eda53b by Abseil Team <absl-team@google.com>:

Fix sample template instantiation.

PiperOrigin-RevId: 246354617

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29a23c6835f872948d09b24d890385bf195bc995 by Abseil Team <absl-team@google.com>:

Fix incorrectly copy-pasted static_assert in absl::optional::value_or

The static_assert for a move-constructible type previously said the type must be copy-constructible.

PiperOrigin-RevId: 246313827

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41884d5872d4ea2c67875b00144b8c8a5859a295 by Greg Falcon <gfalcon@google.com>:

Import of CCTZ from GitHub.

PiperOrigin-RevId: 245418790

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7f90a7f94cdd5e21232c749efe952a750b5c43a2 by Abseil Team <absl-team@google.com>:

Internal change

PiperOrigin-RevId: 245412658

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730a329cf047d54b46971fce1781edd857208c2a by Greg Falcon <gfalcon@google.com>:

internal change

PiperOrigin-RevId: 245293234

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cf0216be6338200cbb18167d3f3b2e98e372be77 by Greg Falcon <gfalcon@google.com>:

Internal change

PiperOrigin-RevId: 245288164
GitOrigin-RevId: 78293ba4eb4981991ae7e6edd25eb9245fcd7515
Change-Id: I5ea9a852c36c722bae2d6be65fb7f72473d94ab6

1 files changed, 60 insertions, 0 deletions

diff --git a/absl/flags/internal/path_util.h b/absl/flags/internal/path_util.h
new file mode 100644
index 000000000000..5615c0e6c590
--- /dev/null
+++ b/absl/flags/internal/path_util.h
@@ -0,0 +1,60 @@
+//
+//  Copyright 2019 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef ABSL_FLAGS_INTERNAL_PATH_UTIL_H_
+#define ABSL_FLAGS_INTERNAL_PATH_UTIL_H_
+
+#include "absl/strings/match.h"
+#include "absl/strings/string_view.h"
+
+namespace absl {
+namespace flags_internal {
+
+// A portable interface that returns the basename of the filename passed as an
+// argument. It is similar to basename(3)
+// <https://linux.die.net/man/3/basename>.
+// For example:
+//     flags_internal::Basename("a/b/prog/file.cc")
+// returns "file.cc"
+//     flags_internal::Basename("file.cc")
+// returns "file.cc"
+inline absl::string_view Basename(absl::string_view filename) {
+  auto last_slash_pos = filename.find_last_of("/\\");
+
+  return last_slash_pos == absl::string_view::npos
+             ? filename
+             : filename.substr(last_slash_pos + 1);
+}
+
+// A portable interface that returns the directory name of the filename
+// passed as an argument, including the trailing slash.
+// Returns the empty string if a slash is not found in the input file name.
+// For example:
+//      flags_internal::Package("a/b/prog/file.cc")
+// returns "a/b/prog/"
+//      flags_internal::Package("file.cc")
+// returns ""
+inline absl::string_view Package(absl::string_view filename) {
+  auto last_slash_pos = filename.find_last_of("/\\");
+
+  return last_slash_pos == absl::string_view::npos
+             ? absl::string_view()
+             : filename.substr(0, last_slash_pos + 1);
+}
+
+}  // namespace flags_internal
+}  // namespace absl
+
+#endif  // ABSL_FLAGS_INTERNAL_PATH_UTIL_H_