xrepo env can't work with find_tool on windows

[star-hengxing]

$ xrepo env -b zig xmake f -c --toolchain=zig
# print in https://github.com/xmake-io/xmake/blob/e553279e918bf8e693f2d59ef685809ae62264d1/xmake/toolchains/zig/xmake.lua#L61
{
  name = "zig",
  version = "0.14.0",
  program = "zig"
}
$ xmake
error: cannot get program for zc

workaround

add_requires("zig")
set_toolchains("@zig")

$ xmake f -c
checking for platform ... windows
checking for architecture ... x64
checking for Microsoft Visual Studio (x64) version ... 2022
checking for Microsoft C/C++ Compiler (x64) version ... 19.43.34808
{
  name = "zig",
  program = "C:\Users\star\AppData\Local\.xmake\packages\z\zig\0.14.0\71e26976fbe64ccb86f253cf965d8dcc\zig",
  version = "0.14.0"
}
$ xmake
[ 60%]: compiling.release src\main.zig
[ 60%]: compiling.release src\test.zig
[ 80%]: linking.release test.exe
[100%]: build ok, spent 4.797s

[waruqi]

没法复现

ruki-2:console ruki$ xrepo env -b zig xmake f -c --toolchain=zig
checking for platform ... macosx
checking for architecture ... x86_64
checking for Xcode directory ... /Applications/Xcode.app
checking for SDK version of Xcode for macosx (x86_64) ... 15.2
checking for Minimal target version of Xcode for macosx (x86_64) ... 15.1
note: install or modify (m) these toolchain packages first (pass -y to skip confirm)?
in xmake-repo:
  -> zig 0.13.0 [host]
please input: y (y/n/m)

  => download https://ziglang.org/download/0.13.0/zig-macos-x86_64-0.13.0.tar.xz .. ok
  => install zig 0.13.0 .. ok
checking for platform ... macosx
checking for architecture ... x86_64
ruki-2:console ruki$ xmake -rv
checking for /Users/ruki/.xmake/packages/z/zig/0.13.0/8e56088fcf164bc4af317c8d7596a056/zig ... ok
checking for the zig compiler (zc) ... zig
checking for /Users/ruki/.xmake/packages/z/zig/0.13.0/8e56088fcf164bc4af317c8d7596a056/zig ... ok
checking for the zig compiler (zc) ... zig
checking for flags (-O ReleaseFast) ... ok
checking for flags (--cache-dir build/.objs/test/macosx/x86_64/release/zig-cache) ... ok
[ 60%]: compiling.release src/main.zig
/Users/ruki/.xmake/packages/z/zig/0.13.0/8e56088fcf164bc4af317c8d7596a056/zig build-obj -target x8
6_64-macos-none -O ReleaseFast --cache-dir build/.objs/test/macosx/x86_64/release/zig-cache -femit
-bin=build/.objs/test/macosx/x86_64/release/src/main.zig.o src/main.zig
[ 60%]: compiling.release src/test.zig
/Users/ruki/.xmake/packages/z/zig/0.13.0/8e56088fcf164bc4af317c8d7596a056/zig build-obj -target x8
6_64-macos-none -O ReleaseFast --cache-dir build/.objs/test/macosx/x86_64/release/zig-cache -femit
-bin=build/.objs/test/macosx/x86_64/release/src/test.zig.o src/test.zig
checking for /Users/ruki/.xmake/packages/z/zig/0.13.0/8e56088fcf164bc4af317c8d7596a056/zig ... ok
checking for the zig linker (zcld) ... zig
[ 80%]: linking.release test
/Users/ruki/.xmake/packages/z/zig/0.13.0/8e56088fcf164bc4af317c8d7596a056/zig build-exe -target x8
6_64-macos-none -fstrip -dead_strip -femit-bin=build/macosx/x86_64/release/test build/.objs/test/m
acosx/x86_64/release/src/main.zig.o build/.objs/test/macosx/x86_64/release/src/test.zig.o
[100%]: build ok, spent 13.669s

[star-hengxing]

那可能只有 windows 出现这种，我猜是 check 时 find_tool 没返回绝对路径，导致 load 只拿到了 zig 而不是一条绝对路径，不知道从哪开始排查 = =

[waruqi]

就是 find_tool 没返回绝对路径而已，这本身也是正常的情况，不算问题，只要能找到就行，问题是你后面执行 xmake -rv 并没有绑定 xrepo env -b zig 也就不会找到了。。

目前 find_tool 以及内部工具链的获取，不强制每个都返回绝对路径的，linux/mac 上可以，是走了 which 给了绝对路径

现在的问题，你这想要强制 zig 必须吐绝对路径 才能支持目前这种用法，那就要改 find_zig 去尝试从 path env 中找了。

不过，我尝试改进了下 find_program ，把 where.exe 调用提前了下，应该也会优先找绝对路径，但是否会 break 其他一些东西，就不好说了，可以观察下。

#6229