This corresponds to the g++ and clang++
option -fvisibility-inlines-hidden on linux. On Windows with MinGW,
this corresponds to -fno-keep-inline-dllexport. That option is
not supported by clang currently.
This is initialized by CMAKE_<LANG>_VISIBILITY_PRESET. The target
property is used as the operand to the -fvisibility= compile option
with GNU compilers and clang.
The variables in this module are used to configure a header file
with defines whose name depends on the name of the target.
As valid names of targets may be invalid for use as defines, convert
the names of the defines used to C identifiers first. This is already
done in C++ code for the DEFINE_SYMBOL property.
This is not as simple as ensuring that the BASE_NAME is a C identifier,
because most of the define names are configurable, and because use of
a BASE_NAME which is not a C identifier, such as 4square can become a
C identifier by specifying a prefix in the generate_export_header
macro.
The CMake language implicitly flattens lists so a ";" in a list element
must be escaped with a backslash. List expansion removes backslashes
escaping semicolons to leave raw semicolons in the values. Teach
ExternalData_Add_Test and ExternalData_Expand_Arguments to re-escape
semicolons found in list elements so the resulting argument lists work
as if constructed directly by the set() command.
For example:
ExternalData_Add_Test(Data NAME test1 COMMAND ... "a\\;b")
ExternalData_Expand_Arguments(Data args2 "c\\;d")
add_test(NAME test2 COMMAND ... ${args2})
should be equivalent to
set(args1 "a\\;b")
add_test(NAME test1 COMMAND ... ${args1})
set(args2 "c\\;d")
add_test(NAME test2 COMMAND ... ${args2})
which is equivalent to
add_test(NAME test1 COMMAND ... "a;b")
add_test(NAME test2 COMMAND ... "c;d")
Note that it is not possible to make ExternalData_Add_Test act exactly
like add_test when quoted arguments contain semicolons because the CMake
language flattens lists when constructing function ARGN values. This
re-escape approach at least allows test arguments to have semicolons.
While at it, teach ExternalData APIs to not transform "DATA{...;...}"
arguments because the contained semicolons are non-sensical.
Suggested-by: Jean-Christophe Fillion-Robin <jchris.fillionr@kitware.com>
Extend the Module.ExternalData test to cover a DATA{} reference whose
name contains a space. Skip the case when the native build tool does
not support spaces.
Use a trailing slash to reference a directory. Require that a list
of associated files be specified to select from within the directory.
One may simply use DATA{Dir/,REGEX:.*} to reference all files but
get a directory passed on the command line.
Refactor use of the ExternalData_SERIES_MATCH value to avoid assuming
that it has no ()-groups that interfere with group indexing.
Extend the Module.ExternalData test to cover this case.
Add a Module.ExternalData test to verify data retrieval and test
argument DATA{} references.
Add a RunCMake.ExternalData test to verify error handling and automatic
transformation of a raw data to a content link and staged object.