Provide a standardized way to handle the C++ "standard" headers
customized to be used with current CMake C++ standard constraints.
Offer under directory `cm` headers which can be used as direct
replacements of the standard ones. For example:
#include <cm/string_view>
can be used safely for CMake development in place of the `<string_view>`
standard header.
Fixes: #19491
Set the MinTypeNameLength option to an impossibly high value in order
to limit the diagnostics to iterators. Leave new expressions and cast
expressions for later.
This replaces `std::ostringstream`, when it is written to only once.
If the single written argument was numeric, `std::to_string` is used instead.
Otherwise, the single written argument is used directly instead of the
`std::ostringstream::str()` invocation.
This patch is generated by a python script that uses regular expressions to
search for string concatenation patterns of the kind
```
std::string str = <ARG0>;
str += <ARG1>;
str += <ARG2>;
...
```
and replaces them with a single `cmStrCat` call
```
std::string str = cmStrCat(<ARG0>, <ARG1>, <ARG2>, ...);
```
If any `<ARGX>` is itself a concatenated string of the kind
```
a + b + c + ...;
```
then `<ARGX>` is split into multiple arguments for the `cmStrCat` call.
If there's a sequence of literals in the `<ARGX>`, then all literals in the
sequence are concatenated and merged into a single literal argument for
the `cmStrCat` call.
Single character strings are converted to single char arguments for
the `cmStrCat` call.
`std::to_string(...)` wrappings are removed from `cmStrCat` arguments,
because it supports numeric types as well as string types.
`arg.substr(x)` arguments to `cmStrCat` are replaced with
`cm::string_view(arg).substr(x)`
Enables the clang-tidy test performance-inefficient-string-concatenation
and replaces all inefficient string concatenations with `cmStrCat`.
Closes: #19555
This adds the following functions to `cmStringAlgorithms`:
- `cmIsSpace`
- `cmTrimWhitespace` (moved from `cmSystemTools::TrimWhitespace`)
- `cmEscapeQuotes` (moved from `cmSystemTools::EscapeQuotes`)
- `cmTokenize` (moved from `cmSystemTools::tokenize` and adapted to
accept `cm::string_view`)
This changes `cmMakefile::AddDefinition` to take a `cm::string_view` as value
argument instead of a `const char *`.
Benefits are:
- `std::string` can be passed to `cmMakefile::AddDefinition` directly without
the `c_str()` plus string length recomputation fallback.
- Lengths of literals passed to `cmMakefile::AddDefinition` can be computed at
compile time.
In various sources uses of `cmMakefile::AddDefinition` are adapted to avoid
`std::string::c_str` calls and the `std::string` is passed directly.
Uses of `cmMakefile::AddDefinition`, where a `nullptr` `const char*` might
be passed to `cmMakefile::AddDefinition` are extended with `nullptr` checks.
An old workaround for `std::allocator_traits<>::value_type` lints from
IWYU on `std::vector<>` usage breaks IWYU's handling of `<memory>`.
Convert the workaround to use the same approach we already use for a
workaround of `std::__decay_and_strip<>::::__type` lints. Then update
the `<memory>` inclusions to follow the now-correct IWYU lints.
Suppress some cases in `Source/cmGeneratorExpressionNode.cxx` and
`Source/cmUVHandlePtr.h` where a few older compilers require a
user-defined default constructor (with `{}`).
Since commit 5a0784ddea (clang-tidy: Pass by value, 2019-01-21), some of
the `RunCMake.{list,PositionIndependentCode}` cases have crashed on an
aarch64 build with GCC 6. Avoiding use of the `std::function` move
constructor avoids the crash. Use a strict preprocessor condition to
use this workaround only where needed.
The operations changed here all are no-ops on empty lists anyways, so
just have them succeed when given non-extant lists.
- `list(REMOVE_ITEM)`
- `list(REMOVE_DUPLICATES)`
- `list(SORT)`
- `list(FILTER)`
- `list(REVERSE)`
Run the `clang-format.bash` script to update all our C and C++ code to a
new style defined by `.clang-format`. Use `clang-format` version 6.0.
* If you reached this commit for a line in `git blame`, re-run the blame
operation starting at the parent of this commit to see older history
for the content.
* See the parent commit for instructions to rebase a change across this
style transition commit.
