In a per-component installation the generated installation scripts
are invoked once for each component.
Per default custom installation script code added by install(CODE|SCRIPT)
only runs for one specific component in this context.
The new ALL_COMPONENTS option allows custom script code to be run once
for each component being installed.
INTERFACE libraries with SOURCES now appear in the generated
buildsystem, so include them in the codemodel output too.
We do not need to bump the `codemodel-v2` object kind minor
version because that was already done in post-3.18 development
by commit 7d6861f367 (fileapi: Extend codemodel targets with
language standard, 2020-06-18).
Fixes: #18608
Since commit e89ad0f94e (install: Allow installing targets created in
another directory, 2018-06-18, v3.13.0-rc1~407^2) we support calling
`install(TARGETS)` for targets created in another directory. However,
install generators are associated with the directory in which the call
to `install()` appears. This may not be the same directory in which the
target is defined. Record in each target the list of install generators
it has.
Fixes: #19546
Offer clients a `project()`-centric view of the build system. This is
similar to the directory-centric view but consolidates subdirectories
that do not call `project()` with a new project name.
Issue: #18398
Co-Author: Kyle Edwards <kyle.edwards@kitware.com>
