ci: Add jobs that run in symlink trees

.gitignore

@@ -3,6 +3,10 @@
 # Common build directories
 /build*/
 
+# CI jobs that run in symlinked trees produce these artifacts.
+/real_work/
+/work
+
 # MacOS Finder files.
 .DS_Store
 

.gitlab-ci.yml

@@ -199,6 +199,18 @@ t:debian12-makefiles-clang:
     variables:
         CMAKE_CI_JOB_NIGHTLY: "true"
 
+t:debian12-ninja-multi-symlinked:
+    extends:
+        - .debian12_ninja_multi_symlinked
+        - .cmake_test_linux_release
+        - .linux_x86_64_tags
+        - .cmake_junit_artifacts
+        - .run_dependent
+        - .needs_centos7_x86_64
+    variables:
+        CMAKE_CI_JOB_NIGHTLY: "true"
+        CMAKE_CI_JOB_NIGHTLY_NINJA: "true"
+
 t:debian12-hip-radeon:
     extends:
         - .debian12_hip_radeon
@@ -399,6 +411,16 @@ b:fedora38-ninja:
     variables:
         CMAKE_CI_JOB_CONTINUOUS: "true"
 
+b:fedora38-makefiles-symlinked:
+    extends:
+        - .fedora38_makefiles_symlinked
+        - .cmake_build_linux
+        - .cmake_build_artifacts
+        - .linux_x86_64_tags
+        - .run_manually
+    variables:
+        CMAKE_CI_JOB_NIGHTLY: "true"
+
 b:debian12-makefiles-inplace:
     extends:
         - .debian12_makefiles_inplace
@@ -449,6 +471,20 @@ t:fedora38-ninja:
     variables:
         CMAKE_CI_JOB_CONTINUOUS: "true"
 
+t:fedora38-makefiles-symlinked:
+    extends:
+        - .fedora38_makefiles_symlinked
+        - .cmake_test_linux
+        - .linux_x86_64_tags_x11
+        - .cmake_test_artifacts
+        - .run_dependent
+    dependencies:
+        - b:fedora38-makefiles-symlinked
+    needs:
+        - b:fedora38-makefiles-symlinked
+    variables:
+        CMAKE_CI_JOB_NIGHTLY: "true"
+
 t:fedora38-ninja-multi:
     extends:
         - .fedora38_ninja_multi
@@ -871,6 +907,16 @@ b:macos-arm64-ninja:
     variables:
         CMAKE_CI_JOB_CONTINUOUS: "true"
 
+b:macos-arm64-ninja-symlinked:
+    extends:
+        - .macos_arm64_ninja_symlinked
+        - .cmake_build_macos
+        - .cmake_build_artifacts
+        - .macos_arm64_tags
+        - .run_manually
+    variables:
+        CMAKE_CI_JOB_NIGHTLY: "true"
+
 b:macos-arm64-pch:
     extends:
         - .macos_arm64_pch
@@ -909,6 +955,21 @@ t:macos-arm64-ninja:
         CMAKE_CI_JOB_CONTINUOUS: "true"
         CMAKE_CI_JOB_NIGHTLY_NINJA: "true"
 
+t:macos-arm64-ninja-symlinked:
+    extends:
+        - .macos_arm64_ninja_symlinked
+        - .cmake_test_macos
+        - .cmake_test_artifacts
+        - .macos_arm64_tags
+        - .run_dependent
+    dependencies:
+        - b:macos-arm64-ninja-symlinked
+    needs:
+        - b:macos-arm64-ninja-symlinked
+    variables:
+        CMAKE_CI_JOB_NIGHTLY: "true"
+        CMAKE_CI_JOB_NIGHTLY_NINJA: "true"
+
 b:macos-x86_64-makefiles:
     extends:
         - .macos_x86_64_makefiles
@@ -968,6 +1029,20 @@ t:macos-arm64-xcode:
     needs:
         - t:macos-arm64-ninja
 
+t:macos-arm64-xcode-symlinked:
+    extends:
+        - .macos_arm64_xcode_symlinked
+        - .cmake_test_macos_external
+        - .macos_arm64_tags_ext
+        - .cmake_junit_artifacts
+        - .run_dependent
+    dependencies:
+        - t:macos-arm64-ninja
+    needs:
+        - t:macos-arm64-ninja
+    variables:
+        CMAKE_CI_JOB_NIGHTLY: "true"
+
 t:macos-x86_64-ninja-ub:
     extends:
         - .macos_x86_64_ninja_ub

.gitlab/ci/configure_debian12_ninja_multi_symlinked.cmake

@@ -0,0 +1,3 @@
+include("${CMAKE_CURRENT_LIST_DIR}/configure_symlinked_common.cmake")
+include("${CMAKE_CURRENT_LIST_DIR}/configure_debian12_ninja_common.cmake")
+set(CMake_TEST_UseSWIG "OFF" CACHE BOOL "")

.gitlab/ci/configure_fedora38_makefiles_symlinked.cmake

@@ -0,0 +1,2 @@
+include("${CMAKE_CURRENT_LIST_DIR}/configure_symlinked_common.cmake")
+include("${CMAKE_CURRENT_LIST_DIR}/configure_fedora38_common.cmake")

.gitlab/ci/configure_macos_arm64_ninja_symlinked.cmake

@@ -0,0 +1,2 @@
+include("${CMAKE_CURRENT_LIST_DIR}/configure_symlinked_common.cmake")
+include("${CMAKE_CURRENT_LIST_DIR}/configure_macos_arm64_ninja.cmake")

.gitlab/ci/configure_macos_arm64_xcode_symlinked.cmake

@@ -0,0 +1,2 @@
+include("${CMAKE_CURRENT_LIST_DIR}/configure_symlinked_common.cmake")
+include("${CMAKE_CURRENT_LIST_DIR}/configure_macos_arm64_xcode.cmake")

.gitlab/ci/configure_symlinked_common.cmake

@@ -0,0 +1,7 @@
+# Ensure that the symlink tree is set up correctly.
+if(NOT CMAKE_SOURCE_DIR STREQUAL "$ENV{CI_PROJECT_DIR}/work/cmake")
+  message(FATAL_ERROR "Expected value of CMAKE_SOURCE_DIR:\n  $ENV{CI_PROJECT_DIR}/work/cmake\nActual value:\n  ${CMAKE_SOURCE_DIR}")
+endif()
+if(NOT CMAKE_BINARY_DIR STREQUAL "$ENV{CI_PROJECT_DIR}/work/build")
+  message(FATAL_ERROR "Expected value of CMAKE_BINARY_DIR:\n  $ENV{CI_PROJECT_DIR}/work/build\nActual value:\n  ${CMAKE_BINARY_DIR}")
+endif()

.gitlab/ci/env.sh

@@ -9,6 +9,16 @@ quietly() {
   rm -f "$log"
 }
 
+if test -n "$CMAKE_CI_IN_SYMLINK_TREE"; then
+  mkdir -p "$CI_PROJECT_DIR/real_work/work/build"
+  ln -s real_work/work "$CI_PROJECT_DIR/work"
+  git worktree prune
+  git worktree add "$CI_PROJECT_DIR/work/cmake" HEAD
+
+  # Assert that the hash matches.
+  test "$(git -C "$CI_PROJECT_DIR/work/cmake" rev-parse HEAD)" = "$(git -C "$CI_PROJECT_DIR" rev-parse HEAD)"
+fi
+
 if test -r ".gitlab/ci/env_${CMAKE_CONFIGURATION}.sh"; then
   source ".gitlab/ci/env_${CMAKE_CONFIGURATION}.sh"
 fi

.gitlab/ci/env_debian12_ninja_multi_symlinked.sh

@@ -0,0 +1,5 @@
+export MY_RUBY_HOME="/usr/local/rvm/rubies/ruby-3.2.2"
+
+if test -z "$CI_MERGE_REQUEST_ID"; then
+  source .gitlab/ci/swift-env.sh
+fi

.gitlab/ci/env_fedora38_makefiles_symlinked.cmake

@@ -0,0 +1 @@
+include("${CMAKE_CURRENT_LIST_DIR}/env_fedora38_makefiles.cmake")

.gitlab/ci/env_fedora38_makefiles_symlinked.sh

@@ -0,0 +1 @@
+. .gitlab/ci/env_fedora38_makefiles.sh

.gitlab/ci/env_macos_arm64_ninja_symlinked.sh

@@ -0,0 +1 @@
+. .gitlab/ci/env_macos_arm64_ninja.sh

.gitlab/ci/gitlab_ci.cmake

@@ -5,8 +5,13 @@ endif ()
 
 # Set up the source and build paths.
 set(CTEST_SOURCE_DIRECTORY "$ENV{CI_PROJECT_DIR}")
+if("$ENV{CMAKE_CI_IN_SYMLINK_TREE}")
+  set(CTEST_SOURCE_DIRECTORY "$ENV{CI_PROJECT_DIR}/work/cmake")
+endif()
 if("$ENV{CMAKE_CI_INPLACE}")
   set(CTEST_BINARY_DIRECTORY "${CTEST_SOURCE_DIRECTORY}")
+elseif("$ENV{CMAKE_CI_IN_SYMLINK_TREE}")
+  set(CTEST_BINARY_DIRECTORY "$ENV{CI_PROJECT_DIR}/work/build")
 else()
   set(CTEST_BINARY_DIRECTORY "${CTEST_SOURCE_DIRECTORY}/build")
 endif()

.gitlab/os-linux.yml

@@ -137,6 +137,16 @@
         CMAKE_CI_NO_INSTALL: 1
         CTEST_NO_WARNINGS_ALLOWED: 1
 
+.debian12_ninja_multi_symlinked:
+    extends: .debian12
+
+    variables:
+        CMAKE_CONFIGURATION: debian12_ninja_multi_symlinked
+        CMAKE_GENERATOR: "Ninja Multi-Config"
+        CTEST_NO_WARNINGS_ALLOWED: 1
+        CMAKE_CI_IN_SYMLINK_TREE: 1
+        CMAKE_CI_BUILD_DIR: "real_work/work/build"
+
 .debian12_extdeps:
     extends: .debian12
 
@@ -185,6 +195,16 @@
         CTEST_NO_WARNINGS_ALLOWED: 1
         CMAKE_GENERATOR: "Unix Makefiles"
 
+.fedora38_makefiles_symlinked:
+    extends: .fedora38
+
+    variables:
+        CMAKE_CONFIGURATION: fedora38_makefiles_symlinked
+        CTEST_NO_WARNINGS_ALLOWED: 1
+        CMAKE_GENERATOR: "Unix Makefiles"
+        CMAKE_CI_IN_SYMLINK_TREE: 1
+        CMAKE_CI_BUILD_DIR: "real_work/work/build"
+
 ### Clang Compiler
 
 .debian12_makefiles_clang:

.gitlab/os-macos.yml

@@ -38,6 +38,15 @@
         CMAKE_CONFIGURATION: macos_arm64_ninja
         CTEST_NO_WARNINGS_ALLOWED: 1
 
+.macos_arm64_ninja_symlinked:
+    extends: .macos_build
+
+    variables:
+        CMAKE_CONFIGURATION: macos_arm64_ninja_symlinked
+        CTEST_NO_WARNINGS_ALLOWED: 1
+        CMAKE_CI_IN_SYMLINK_TREE: 1
+        CMAKE_CI_BUILD_DIR: "real_work/work/build"
+
 .macos_arm64_pch:
     extends: .macos_arm64_ninja
 
@@ -86,6 +95,16 @@
         CMAKE_GENERATOR: Xcode
         CMAKE_CI_NIGHTLY_IGNORE_DEPS: "true"
 
+.macos_arm64_xcode_symlinked:
+    extends: .macos
+
+    variables:
+        CMAKE_CONFIGURATION: macos_arm64_xcode_symlinked
+        CMAKE_GENERATOR: Xcode
+        CMAKE_CI_NIGHTLY_IGNORE_DEPS: "true"
+        CMAKE_CI_IN_SYMLINK_TREE: 1
+        CMAKE_CI_BUILD_DIR: "real_work/work/build"
+
 .macos_arm64_xcode_ub:
     extends: .macos