From 45f637cc09c94b0eb5cf1ebc739b5d3eb77aef33 Mon Sep 17 00:00:00 2001
From: Philippe Proulx <eeppeliteloop@gmail.com>
Date: Wed, 15 Nov 2023 00:37:27 -0500
Subject: [PATCH] cpp-common: add `bt2s::string_view`, alias of
 `bpstd::string_view`

In order to avoid having all sorts of external namespaces, make
`bt2s::string_view` an alias of `nonstd::string_view`, and make sure
everything in the project uses `bt2s::string_view`.

Also add aliases for other STL types of `<string_view>`, like the
`bt2s::basic_string_view` class template.

This will make it possible to easily change the implementation without
changing the code using it indirectly (only
`cpp-common/bt2s/string-view.hpp` will change).

Move `cpp-common/string_view.hpp` to
`cpp-common/vendor/string_view-standalone/string_view.hpp` to make it
clear it's an external project.

Signed-off-by: Philippe Proulx <eeppeliteloop@gmail.com>
Change-Id: I5172f642f5490b4a7eb21ed7cca55039452dc9b8
Reviewed-on: https://review.lttng.org/c/babeltrace/+/11392
Reviewed-by: Simon Marchi <simon.marchi@efficios.com>
CI-Build: Simon Marchi <simon.marchi@efficios.com>
Tested-by: jenkins <jenkins@lttng.org>
---
 src/Makefile.am                               |  5 ++--
 src/cpp-common/bt2s/string-view.hpp           | 24 +++++++++++++++++++
 .../string_view-standalone}/string_view.hpp   |  0
 tools/format-cpp.sh                           |  1 -
 4 files changed, 27 insertions(+), 3 deletions(-)
 create mode 100644 src/cpp-common/bt2s/string-view.hpp
 rename src/cpp-common/{ => vendor/string_view-standalone}/string_view.hpp (100%)

diff --git a/src/Makefile.am b/src/Makefile.am
index 23acb9e1..cf315687 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -55,9 +55,10 @@ noinst_HEADERS = \
 	cpp-common/bt2c/vector.hpp \
 	cpp-common/bt2s/make-unique.hpp \
 	cpp-common/bt2s/optional.hpp \
+	cpp-common/bt2s/string-view.hpp \
 	cpp-common/nlohmann/json.hpp \
-	cpp-common/string_view.hpp \
-	cpp-common/vendor/optional-lite/optional.hpp
+	cpp-common/vendor/optional-lite/optional.hpp \
+	cpp-common/vendor/string_view-standalone/string_view.hpp
 
 ## This target generates an include file that contains the git version
 ## string of the current branch, it must be continuously updated when
diff --git a/src/cpp-common/bt2s/string-view.hpp b/src/cpp-common/bt2s/string-view.hpp
new file mode 100644
index 00000000..8cdafd84
--- /dev/null
+++ b/src/cpp-common/bt2s/string-view.hpp
@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2023 Philippe Proulx <pproulx@efficios.com>
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#ifndef BABELTRACE_CPP_COMMON_BT2S_STRING_VIEW_HPP
+#define BABELTRACE_CPP_COMMON_BT2S_STRING_VIEW_HPP
+
+#include "cpp-common/vendor/string_view-standalone/string_view.hpp"
+
+namespace bt2s {
+
+template <typename CharT, typename TraitsT = std::char_traits<CharT>>
+using basic_string_view = bpstd::basic_string_view<CharT, TraitsT>;
+
+using string_view = bpstd::string_view;
+using wstring_view = bpstd::wstring_view;
+using u16string_view = bpstd::u16string_view;
+using u32string_view = bpstd::u32string_view;
+
+} /* namespace bt2s */
+
+#endif /* BABELTRACE_CPP_COMMON_BT2S_STRING_VIEW_HPP */
diff --git a/src/cpp-common/string_view.hpp b/src/cpp-common/vendor/string_view-standalone/string_view.hpp
similarity index 100%
rename from src/cpp-common/string_view.hpp
rename to src/cpp-common/vendor/string_view-standalone/string_view.hpp
diff --git a/tools/format-cpp.sh b/tools/format-cpp.sh
index 04444ddc..754b04d2 100755
--- a/tools/format-cpp.sh
+++ b/tools/format-cpp.sh
@@ -45,7 +45,6 @@ format_cpp() {
 	# files in specific subdirectories.
 	find "$(realpath "$root_dir")" \( -name '*.cpp' -o -name '*.hpp' \) \
 		! -path '*/src/cpp-common/vendor/*' \
-		! -path '*/src/cpp-common/string_view.hpp' \
 		! -path '*/src/cpp-common/nlohmann/json.hpp' \
 		! -path '*/src/plugins/ctf/common/metadata/parser.*' \
 		! -path '*/src/plugins/ctf/common/metadata/lexer.*' \
-- 
2.34.1