[vcpkg scripts] Use ninja from vcpkg fetch

[Neumann-A]

No description provided.

[Neumann-A]

Could also be:

Suggested change

	COMMAND "$ENV{VCPKG_COMMAND}" fetch ninja
	COMMAND "$ENV{VCPKG_COMMAND}" fetch "${program_name}"

if we want to generalize this pattern somehow?

[dg0yt]

Isn't testing and setting NINJA the responsibility of the vfap.cmake script?
Should this script just return the directory in paths_to_search?

[Neumann-A]

Isn't testing and setting NINJA the responsibility of the vfap.cmake script?

In general yes but:

• vcpkg fetch ninja should always return the correct minimum version -> see CMake
• NINJA needs to be overwritable by the user from a triplet.

[dg0yt]

Isn't testing and setting NINJA the responsibility of the vfap.cmake script?

In general yes but:

• vcpkg fetch ninja should always return the correct minimum version -> see CMake

This is vcpkg fetch responsibility now, and it works AFAICS on my computer.

• NINJA needs to be overwritable by the user from a triplet.

It is AFAICS.

vcpkg/scripts/cmake/vcpkg_find_acquire_program.cmake

Lines 97 to 100 in cf035d9

	function(vcpkg_find_acquire_program program)
	if(${program})
	return()
	endif()

These per-program scripts are really meant to just provide the most specific part of the implementation.

[Neumann-A]

These per-program scripts are really meant to just provide the most specific part of the implementation.

So you want:

vcpkg_execute_in_download_mode(
    COMMAND "$ENV{VCPKG_COMMAND}" fetch ninja
    RESULT_VARIABLE error_code
    OUTPUT_VARIABLE NINJA
    WORKING_DIRECTORY "${DOWNLOADS}"
)
string(STRIP "${NINJA}" NINJA)
set(NINJA "${NINJA}" CACHE STRING "" FORCE)
return() # so that the rest of vcpkg_find_acquire_program is not executed. 

?

or even

set(program_name ninja)
set(use_vcpkg_fetch ON)

some impl. doing vcpkg fetch in vcpkg_find_acquire_program?

I don't see a reason to do the last one yet.

I mean the only goal here is to not duplicate the ninja information and keep vcpkg_find_acquire_program(NINJA) intact.

[dg0yt]

More like

set(program_name ninja)
vcpkg_execute_in_download_mode(
    COMMAND "$ENV{VCPKG_COMMAND}" fetch ninja
    RESULT_VARIABLE error_code
    OUTPUT_VARIABLE ninja
    OUTPUT_STRIP_TRAILING_WHITESPACE
    WORKING_DIRECTORY "${DOWNLOADS}"
)
cmake_path(GET ninja PARENT_PATH paths_to_search)

but I see that we already have the ultimate NINJA at that point. It is just that it is not clear from which scope we would be return()ing.

[Neumann-A]

It is just that it is not clear from which scope we would be return()ing.

The return is actually not needed. Just an unnecessary early return, so we could go without it.