Add env var for CMake build dir to avoid too long path on Windows (#115)

* add env var for build dir to avoid too long path on windows

* use VINCA_ prefix

* also on unix

* use custom cmake build dir on win CI to avoid too long path

* format

Author: olivier-roussel

vinca/generate_gha.py

@@ -370,7 +370,10 @@ def build_win_pipeline(stages, trigger_branch, outfile="win.yml", azure_template
                 "runs-on": vm_imagename,
                 "strategy": {"fail-fast": False},
                 "needs": prev_batch_keys,
-                "env": {"CONDA_BLD_PATH": "C:\\\\bld\\\\"},
+                "env": [
+                    {"CONDA_BLD_PATH": "C:\\\\bld\\\\"},
+                    {"VINCA_CUSTOM_CMAKE_BUILD_DIR": "C:\\\\x\\\\"},
+                ],
                 "steps": [
                     {"name": "Checkout code", "uses": "actions/checkout@v6"},
                     {

vinca/templates/bld_ament_cmake.bat.in

@@ -8,6 +8,11 @@ set "PYTHONPATH=%LIBRARY_PREFIX%\lib\site-packages;%SP_DIR%"
 set CC=cl.exe
 set CXX=cl.exe
 
+:: If defined, can use a custom CMake build directory which can be useful
+:: to avoid too long path problems on windows
+if defined VINCA_CUSTOM_CMAKE_BUILD_DIR (
+    cd /d "%VINCA_CUSTOM_CMAKE_BUILD_DIR%"
+)
 rd /s /q build
 mkdir build
 pushd build

vinca/templates/build_ament_cmake.sh.in

@@ -3,6 +3,9 @@
 
 set -eo pipefail
 
+if [[ -n "$VINCA_CUSTOM_CMAKE_BUILD_DIR" ]]; then
+    cd "$VINCA_CUSTOM_CMAKE_BUILD_DIR"
+fi
 rm -rf build
 mkdir build
 cd build