The ExternalData_LINK_CONTENT option tells ExternalData to convert real
data files it finds into content links and to "stage" the original
content in a ".ExternalData_<algo>_<hash>" file. However, after a data
object has been staged it is possible that a user-provided pattern in
the "REGEX:" option will later match the staged object file. We must
not process staged object files even when a user pattern matches them.
Fix the implementation to not match a staged object file as a normal
data file for conversion. Extend the RunCMake.ExternalData test to
cover this case.
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>
Each data file to be created in the build tree corresponds one-to-one with
a raw file or content link in the source tree. Use the MAIN_DEPENDENCY of
add_custom_command to attach the build rule to the source tree file. This
looks much nicer in the IDE project file browser and avoids ".rule" files.
Use private global variables _ExternalData_REGEX_(ALGO|EXT) to match the
possible hash algorithm names and extensions in regular expressions.
Use "file(<algo>)" instead of "cmake -E md5sum" to compute hashes
without a child process and to support more hash algorithms.
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.
Automatic series recognition can generate false positives too easily
when the default series configuration is flexible enough to handle
common cases. Avoid false positives by requiring an explicit syntax to
activate series recognition. Choose the syntax DATA{<name>,:} to be
short, simple, and look like a vertical ellipsis.
This allows us to improve the default series match configuration. Allow
series references to contain one of the numbered file names. Allow '-'
as a separator in addition to '.' and '_'. Document what the default
configuration matches. Also provide more options to configure series
<name> parsing.
Take files we previously distributed in ITK 4.3.1:
CMake/ExternalData.cmake
CMake/ExternalData_config.cmake.in
and add them for distribution in upstream CMake. Update the copyright
notice block format to follow CMake conventions.