Extend target checks in cmake, in case it's run directly and not via
idf.py or if idf.py misses something. This may happen
for example if cmake variables are set in project's CMakeLists.txt.
Some clean-ups are included along with the new checks and tests.
1. __target_check() function is removed. IIUC it should never fail,
because the selected target is explicitly passed as environmental
variable to kconfgen. Meaning the IDF_TARGET from environment variable may
not be actually used in kconfgen if IDF_TARGET is already set it cmake cache.
Note that the IDF_TARGET environment variable used for kconfgen is not
based on the actual IDF_TARGET environment variable set for idf.py, but
rather on the value set in __target_init() with
set(IDF_TARGET ${env_idf_target} CACHE STRING "IDF Build Target")
My understanding is that the original check was introduced to handle
situation, where IDF_TARGET was already set in cmake's cache and
the IDF_TARGET from environment variable was different. Since
the kconfgen would use the original environment variable(not
explicitly passed as it is now) the IDF_TARGET in cmake and in
sdkconfig could differ. IOW I think the original check was introduced
to cope with the following cmake behaviour
set(VARIABLE "value1" CACHE STRING "test variable")
set(VARIABLE "value2" CACHE STRING "test variable")
message("Variable value: ${VARIABLE}")
output: Variable value: value1
2. I scratched by head how it is possible that the following code
in __target_check()
if(NOT ${IDF_TARGET} STREQUAL ${env_idf_target})
could fail if IDF_TARGET is not set. For example in clean project
IDF_TARGET=esp32 idf.py reconfigure
Here env_idf_target==esp32 and IDF_TARGET is not set, so I would
expect that cmake will fail with error message that the cache
and env target do not match. The thing is that the variable
evaluation is done before the if command, so it actually
sees this
if(NOT STREQUAL esp32)
which is false and the error is not printed. It can be seen
with 'cmake --trace-expand' command. I don't know if this
was used on purpose or it worked just as a coincidence, but
I find it very confusing, so I added explicit check if the
IDF_TARGET is defined before the actual check. Same for
CMAKE_TOOLCHAIN_FILE.
3. Error messages are not formated(line-wrapped) by cmake's markup
so it's easier to check the output in tests.
Signed-off-by: Frantisek Hrbata <frantisek.hrbata@espressif.com>
Previously get_idf_build_env didn't include the default environment
(os.environ) in its output, so the environment only contained the
variables returned by "idf_tools.py export".
If PATH already contains all the right paths, "idf_tools.py export"
doesn't return the PATH variable.
Therefore the environment returned by get_idf_build_env was usually
incomplete. Fix by combining the output of "idf_tools.py export" with
os.environ.
