Try to be a bit more consistent about:
- Placing angle brackets around text which serves as a placeholder
rather than being literal.
- Using curly brackets rather than angle brackets to denote groups where
one of the options is required.
- Describing optional list arguments like `<x>...` rather than
`[<x>...]`. (Instances of lists not associated with keywords are
intentionally left as-is, however.)
Also, teach our CMake lexer to understand curly braces used as above
(prior uses were only in parsed literals without syntax highlighting),
and to highlight them (and remaining uses of angle braces) as the type
Punctuation rather than the type Operator, for consistency with square
braces.
Since commit ffc06c1239 (Teach find_(library|file|path) to get prefixes
from PATH, 2015-02-18, v3.3.0-rc1~430^2) we search in `<prefix>/include`
and `<prefix>/lib` directories for prefixes with `bin` directories in
the `PATH` environment variable. The motivation was to search the
installation prefixes of MSYS and MinGW development environments
automatically.
This behavior can search undesired prefixes that happen to be in the
`PATH` for unrelated reasons. It was reverted for non-Windows hosts
within a year by commit b30b32a493 (Drop find_(library|file|path)
prefixes from PATH on non-Windows, 2016-05-09, v3.6.0-rc1~82^2) but was
kept on Windows hosts to support its motivating use case. However,
similar problems have since been observed on Windows. For example,
commit 955d6245c1 (MSVC: Revert "Teach find_library to consider the
'libfoo.a' naming convention", 2022-11-28, v3.25.1~6^2) was primarily
due to undesired discovery of libraries in `PATH`-derived prefixes.
Since commit 5e5132e1b1 (MinGW: Search for packages in standard MSYSTEM
environment prefixes, 2023-09-11) we search MSYS and MinGW environments'
prefixes explicitly, so `PATH`-derived prefixes are no longer needed for
the original motivating use case.
Fixes: #24216
The documentation of the find-commands was pointing to the
cmake variables CMAKE_PREFIX_PATH, CMAKE_INCLUDE_PATH etc.
also in the section for environment variables. Now they point
to the documentation for the respective environment variables.
This feature was originally added by commit v3.9.0-rc1~71^2~2 (find_*:
Add a new PackageRoot search path group, 2017-05-03) and documented by
commit v3.9.0-rc1~71^2 (find_*: Add docs for PackageRoot search path
group, 2017-05-03). However, we had to disable the feature and remove
the documentation in commit v3.9.1~2^2 (find_*: Disable the PACKAGE_ROOT
search path group for CMake 3.9, 2017-08-08) due to breaking projects
that used `PackageName_ROOT` variables themselves.
Add policy `CMP0074` to restore the `PackageName_ROOT` variable behavior
in a compatible way. Also revise the stack of root paths to store the
paths themselves rather than the package names. This way the policy can
be considered at the `find_package` call site instead of individual
`find_` calls inside a find module.
Co-Author: Chuck Atkins <chuck.atkins@kitware.com>
Issue: #17144
Disable the feature added by commit v3.9.0-rc1~71^2~2 (find_*: Add a new
PackageRoot search path group, 2017-05-03) and remove documentation
added by commit v3.9.0-rc1~71^2 (find_*: Add docs for PackageRoot search
path group, 2017-05-03). Unfortunately the name `<pkg>_ROOT` may
already be set by projects for their own incompatible purposes. Disable
the behavior change for now to fix the regression for CMake 3.9. We can
restore it later with a policy.
In order to keep the implementation and tests working, add an
undocumented variable we can use in the tests to enable the behavior
before the policy is introduced.
Fixes: #17144
When more than one value is given to the NAMES option this command by
default will consider one name at a time and search every directory for
it. Add a NAMES_PER_DIR option to tell this command to consider one
directory at a time and search for all names in it.
These documents were represented in the builtin documentation using a
common starting point with placeholders substituted by each command.
Convert them back to this approach using the reStructuredText include
directive and substitutions to avoid duplication.
