project: Always set <PROJECT-NAME>_* as normal variables

Re-introduce the behavior originally introduced in CMake 3.30.3 by
commit c1ece78d11 (project: non cache <project> prefix variables are
also created, 2024-08-27, v3.30.3~2^2), but this time with a policy for
compatibility.

Issue: #25714
Issue: #26243

10 files changed, 56 insertions, 11 deletions

diff --git a/Tests/RunCMake/project/CMP0180-NEW-stdout.txt b/Tests/RunCMake/project/CMP0180-NEW-stdout.txt
new file mode 100644
index 0000000..34e5d49
--- /dev/null
+++ b/Tests/RunCMake/project/CMP0180-NEW-stdout.txt
@@ -0,0 +1,16 @@
+(-- )?From subdir1:
+  CMP0180-NEW_SOURCE_DIR = [^
+]+/project/subdir1
+  CMP0180-NEW_BINARY_DIR = [^
+]+/project/CMP0180-NEW-build/subdir1
+  CMP0180-NEW_IS_TOP_LEVEL = OFF
+(-- )?From subdir2:
+  CMP0180-NEW_SOURCE_DIR = [^
+]+/project
+  CMP0180-NEW_BINARY_DIR = [^
+]+/project/CMP0180-NEW-build
+  CMP0180-NEW_IS_TOP_LEVEL = ON
+(-- )?  sub2proj_SOURCE_DIR = [^
+]+/project/subdir2
+  sub2proj_BINARY_DIR = [^
+]+/project/CMP0180-NEW-build/subdir2
diff --git a/Tests/RunCMake/project/CMP0180-NEW.cmake b/Tests/RunCMake/project/CMP0180-NEW.cmake
new file mode 100644
index 0000000..71f8b84
--- /dev/null
+++ b/Tests/RunCMake/project/CMP0180-NEW.cmake
@@ -0,0 +1,2 @@
+# CMP0180 is handled in CMakeLists.txt
+include(CMP0180.cmake)
diff --git a/Tests/RunCMake/project/CMP0180-OLD-stdout.txt b/Tests/RunCMake/project/CMP0180-OLD-stdout.txt
new file mode 100644
index 0000000..4ef55a4
--- /dev/null
+++ b/Tests/RunCMake/project/CMP0180-OLD-stdout.txt
@@ -0,0 +1,16 @@
+(-- )?From subdir1:
+  CMP0180-OLD_SOURCE_DIR = [^
+]+/project/subdir1
+  CMP0180-OLD_BINARY_DIR = [^
+]+/project/CMP0180-OLD-build/subdir1
+  CMP0180-OLD_IS_TOP_LEVEL = OFF
+(-- )?From subdir2:
+  CMP0180-OLD_SOURCE_DIR = [^
+]+/project/subdir1
+  CMP0180-OLD_BINARY_DIR = [^
+]+/project/CMP0180-OLD-build/subdir1
+  CMP0180-OLD_IS_TOP_LEVEL = OFF
+(-- )?  sub2proj_SOURCE_DIR = [^
+]+/project/subdir2
+  sub2proj_BINARY_DIR = [^
+]+/project/CMP0180-OLD-build/subdir2
diff --git a/Tests/RunCMake/project/CMP0180-OLD.cmake b/Tests/RunCMake/project/CMP0180-OLD.cmake
new file mode 100644
index 0000000..71f8b84
--- /dev/null
+++ b/Tests/RunCMake/project/CMP0180-OLD.cmake
@@ -0,0 +1,2 @@
+# CMP0180 is handled in CMakeLists.txt
+include(CMP0180.cmake)
diff --git a/Tests/RunCMake/project/SameProjectVarsSubdir.cmake b/Tests/RunCMake/project/CMP0180.cmake
index 36a7960..36a7960 100644
--- a/Tests/RunCMake/project/SameProjectVarsSubdir.cmake
+++ b/Tests/RunCMake/project/CMP0180.cmake
diff --git a/Tests/RunCMake/project/CMakeLists.txt b/Tests/RunCMake/project/CMakeLists.txt
index 7ddd81d..28146c4 100644
--- a/Tests/RunCMake/project/CMakeLists.txt
+++ b/Tests/RunCMake/project/CMakeLists.txt
@@ -4,6 +4,12 @@ elseif(RunCMake_TEST MATCHES "^CMP0048")
   cmake_minimum_required(VERSION 2.8.12) # old enough to not set CMP0048
 else()
   cmake_minimum_required(VERSION 3.10)
+  # CMP0180 needs to be set before the project() call for these tests
+  if("x${RunCMake_TEST}" STREQUAL "xCMP0180-NEW")
+    cmake_policy(SET CMP0180 NEW)
+  elseif("x${RunCMake_TEST}" STREQUAL "xCMP0180-OLD")
+    cmake_policy(SET CMP0180 OLD)
+  endif()
 endif()
 project(${RunCMake_TEST} NONE)
 include(${RunCMake_TEST}.cmake)
diff --git a/Tests/RunCMake/project/RunCMakeTest.cmake b/Tests/RunCMake/project/RunCMakeTest.cmake
index ed4b8ba..554cdff 100644
--- a/Tests/RunCMake/project/RunCMakeTest.cmake
+++ b/Tests/RunCMake/project/RunCMakeTest.cmake
@@ -63,9 +63,13 @@ run_cmake(CMP0096-OLD)
 run_cmake(CMP0096-NEW)
 
 # We deliberately run these twice to verify behavior of the second CMake run
-run_cmake(SameProjectVarsSubdir)
+run_cmake(CMP0180-OLD)
 set(RunCMake_TEST_NO_CLEAN 1)
-run_cmake(SameProjectVarsSubdir)
+run_cmake(CMP0180-OLD)
+set(RunCMake_TEST_NO_CLEAN 0)
+run_cmake(CMP0180-NEW)
+set(RunCMake_TEST_NO_CLEAN 1)
+run_cmake(CMP0180-NEW)
 set(RunCMake_TEST_NO_CLEAN 0)
 
 run_cmake(NoMinimumRequired)
diff --git a/Tests/RunCMake/project/SameProjectVarsSubdir-stdout.txt b/Tests/RunCMake/project/SameProjectVarsSubdir-stdout.txt
deleted file mode 100644
index 73dadfd..0000000
--- a/Tests/RunCMake/project/SameProjectVarsSubdir-stdout.txt
+++ /dev/null
@@ -1,9 +0,0 @@
-(-- )?  SameProjectVarsSubdir_SOURCE_DIR = [^
-]+/subdir1
-  SameProjectVarsSubdir_BINARY_DIR = [^
-]+/subdir1
-  SameProjectVarsSubdir_IS_TOP_LEVEL = OFF
-(-- )?  sub2proj_SOURCE_DIR = [^
-]+/subdir2
-  sub2proj_BINARY_DIR = [^
-]+/subdir2
diff --git a/Tests/RunCMake/project/subdir1/CMakeLists.txt b/Tests/RunCMake/project/subdir1/CMakeLists.txt
index d6be229..d2d3729 100644
--- a/Tests/RunCMake/project/subdir1/CMakeLists.txt
+++ b/Tests/RunCMake/project/subdir1/CMakeLists.txt
@@ -1 +1,8 @@
 project(${RunCMake_TEST} LANGUAGES NONE)
+
+message(STATUS
+  "From subdir1:\n"
+  "  ${RunCMake_TEST}_SOURCE_DIR = ${${RunCMake_TEST}_SOURCE_DIR}\n"
+  "  ${RunCMake_TEST}_BINARY_DIR = ${${RunCMake_TEST}_BINARY_DIR}\n"
+  "  ${RunCMake_TEST}_IS_TOP_LEVEL = ${${RunCMake_TEST}_IS_TOP_LEVEL}"
+)
diff --git a/Tests/RunCMake/project/subdir2/CMakeLists.txt b/Tests/RunCMake/project/subdir2/CMakeLists.txt
index c28e0c9..cab547f 100644
--- a/Tests/RunCMake/project/subdir2/CMakeLists.txt
+++ b/Tests/RunCMake/project/subdir2/CMakeLists.txt
@@ -1,4 +1,5 @@
 message(STATUS
+  "From subdir2:\n"
   "  ${RunCMake_TEST}_SOURCE_DIR = ${${RunCMake_TEST}_SOURCE_DIR}\n"
   "  ${RunCMake_TEST}_BINARY_DIR = ${${RunCMake_TEST}_BINARY_DIR}\n"
   "  ${RunCMake_TEST}_IS_TOP_LEVEL = ${${RunCMake_TEST}_IS_TOP_LEVEL}"