Tests with old cmake are slow. (no Ninja, no unity, and running slower
than recent versions.)
It also revealed that 3.7.2 2017-01-13 is too old to consume curl via
`find_package()` due to:
```
CMake Error at bld-curl/_pkg/lib/cmake/CURL/CURLConfig.cmake:69 (add_library):
add_library cannot create ALIAS target "CURL::libcurl" because target
"CURL::libcurl_shared" is IMPORTED.
Call Stack (most recent call first):
CMakeLists.txt:48 (find_package)
CMake Error at bld-curl/_pkg/lib/cmake/CURL/CURLConfig.cmake:69 (add_library):
add_library cannot create ALIAS target "CURL::libcurl" because target
"CURL::libcurl_shared" is IMPORTED.
Call Stack (most recent call first):
CMakeLists.txt:49 (find_package)
```
The mitigation for this issue requires 3.11.
Also:
- rename a few existing envs to use the `TEST_` prefix.
- make the `find_package` test provider stage verbose.
- fix issue when consuming with cmake 3.7.2 (all platforms):
```
CMake Error at /home/runner/cmake-3.7.2-Linux-x86_64/share/cmake-3.7/Modules/CMakeFindDependencyMacro.cmake:25 (message):
Invalid arguments to find_dependency. VERSION is empty
Call Stack (most recent call first):
bld-curl/_pkg/lib/cmake/CURL/CURLConfig.cmake:52 (find_dependency)
CMakeLists.txt:48 (find_package)
```
Ref: https://github.com/curl/curl/actions/runs/14906066962/job/41868621979?pr=17293#step:9:1199Closes#17293
- GHA: add cmake integration tests for Windows.
- make them run faster with prefill, unity, Ninja, omitting curl tool.
- also test static libcurl.
- add old-cmake support with auto-detection.
- auto-detect Ninja.
- run consumer test apps to see if they work.
- add support for Windows.
- make it more verbose.
- re-add `ExternalProject` cmake consumer test. It's broken.
- tidy up terminology.
Cherry-picked from #16973Closes#17203
- replace `add_compile_options()`, `add_definitions()` with directory
properties. To harmonize this across all scripts. The new commands are
verbose, but describe better how they work. The syntax is also closer
to setting target properties, helps grepping.
- prefer `CMAKE_INSTALL_PREFIX` over `--prefix` (in tests, CI).
- tidy up cmake invocations.
- formatting.
Closes#16238
Add CMake test project consuming curl via these methods:
`FetchContent`, `add_subdirectory()`, `find_package()`.
Also:
- GHA/distcheck: run these tests in CI.
- cmakelint: exclude a warning for calling "wonky-cased" built-in
CMake functions, such as `FetchContent_Declare()`.
Closes#16126
