file(REAL_PATH): resolve symlinks before '..' components

Previously REAL_PATH would collapse paths before resolving any symlinks
so if `..` crossed a symlink the output from `REAL_PATH` would be wrong.

It looked like REAL_PATH did this by mistake since it was a side-effect
of ensuring we had an absolute path before resolving symlinks.

9 files changed, 48 insertions, 0 deletions

diff --git a/Tests/RunCMake/CMP0152/CMP0152-Common.cmake b/Tests/RunCMake/CMP0152/CMP0152-Common.cmake
new file mode 100644
index 0000000..6429cca
--- /dev/null
+++ b/Tests/RunCMake/CMP0152/CMP0152-Common.cmake
@@ -0,0 +1,5 @@
+file(MAKE_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/dir/")
+file(MAKE_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/dir/nested/")
+file(MAKE_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/dir/nested/bin/")
+file(CREATE_LINK  "${CMAKE_CURRENT_BINARY_DIR}/dir/nested/bin" "${CMAKE_CURRENT_BINARY_DIR}/dir/bin" SYMBOLIC)
+file(REAL_PATH "${CMAKE_CURRENT_BINARY_DIR}/dir/bin/../" real_path)
diff --git a/Tests/RunCMake/CMP0152/CMP0152-NEW-stdout.txt b/Tests/RunCMake/CMP0152/CMP0152-NEW-stdout.txt
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/Tests/RunCMake/CMP0152/CMP0152-NEW-stdout.txt
diff --git a/Tests/RunCMake/CMP0152/CMP0152-NEW.cmake b/Tests/RunCMake/CMP0152/CMP0152-NEW.cmake
new file mode 100644
index 0000000..86a3b55
--- /dev/null
+++ b/Tests/RunCMake/CMP0152/CMP0152-NEW.cmake
@@ -0,0 +1,2 @@
+cmake_policy(SET CMP0152 NEW)
+include(CMP0152-Common.cmake)
diff --git a/Tests/RunCMake/CMP0152/CMP0152-OLD-stderr.txt b/Tests/RunCMake/CMP0152/CMP0152-OLD-stderr.txt
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/Tests/RunCMake/CMP0152/CMP0152-OLD-stderr.txt
diff --git a/Tests/RunCMake/CMP0152/CMP0152-OLD.cmake b/Tests/RunCMake/CMP0152/CMP0152-OLD.cmake
new file mode 100644
index 0000000..62ac300
--- /dev/null
+++ b/Tests/RunCMake/CMP0152/CMP0152-OLD.cmake
@@ -0,0 +1,2 @@
+cmake_policy(SET CMP0152 OLD)
+include(CMP0152-Common.cmake)
diff --git a/Tests/RunCMake/CMP0152/CMP0152-WARN-stderr.txt b/Tests/RunCMake/CMP0152/CMP0152-WARN-stderr.txt
new file mode 100644
index 0000000..8d63168
--- /dev/null
+++ b/Tests/RunCMake/CMP0152/CMP0152-WARN-stderr.txt
@@ -0,0 +1,27 @@
+^CMake Warning \(dev\) at CMP0152-Common\.cmake:[0-9]+ \(file\):
+  Policy CMP0152 is not set: file\(REAL_PATH\) resolves symlinks before
+  collapsing \.\./ components\.  Run "cmake --help-policy CMP0152" for policy
+  details\.  Use the cmake_policy command to set the policy and suppress this
+  warning\.
+
+  From input path:
+
+  [^
+]*/Tests/RunCMake/CMP0152/CMP0152-WARN-build/dir/bin/\.\./
+
+  the policy OLD behavior produces path:
+
+  [^
+]*/Tests/RunCMake/CMP0152/CMP0152-WARN-build/dir
+
+  but the policy NEW behavior produces path:
+
+  [^
+]*/Tests/RunCMake/CMP0152/CMP0152-WARN-build/dir/nested
+
+  Since the policy is not set, CMake is using the OLD behavior for
+  compatibility.
+Call Stack \(most recent call first\):
+  CMP0152-WARN\.cmake:[0-9]+ \(include\)
+  CMakeLists.txt:[0-9]+ \(include\)
+This warning is for project developers\.  Use -Wno-dev to suppress it\.$
diff --git a/Tests/RunCMake/CMP0152/CMP0152-WARN.cmake b/Tests/RunCMake/CMP0152/CMP0152-WARN.cmake
new file mode 100644
index 0000000..e85589e
--- /dev/null
+++ b/Tests/RunCMake/CMP0152/CMP0152-WARN.cmake
@@ -0,0 +1,2 @@
+
+include(CMP0152-Common.cmake)
diff --git a/Tests/RunCMake/CMP0152/CMakeLists.txt b/Tests/RunCMake/CMP0152/CMakeLists.txt
new file mode 100644
index 0000000..5ff8d3e
--- /dev/null
+++ b/Tests/RunCMake/CMP0152/CMakeLists.txt
@@ -0,0 +1,3 @@
+cmake_minimum_required(VERSION 3.23)
+project(${RunCMake_TEST} NONE)
+include(${RunCMake_TEST}.cmake)
diff --git a/Tests/RunCMake/CMP0152/RunCMakeTest.cmake b/Tests/RunCMake/CMP0152/RunCMakeTest.cmake
new file mode 100644
index 0000000..7a9bab3
--- /dev/null
+++ b/Tests/RunCMake/CMP0152/RunCMakeTest.cmake
@@ -0,0 +1,7 @@
+include(RunCMake)
+
+if(NOT CMAKE_GENERATOR_NO_COMPILER_ENV)
+  run_cmake(CMP0152-WARN)
+  run_cmake(CMP0152-OLD)
+  run_cmake(CMP0152-NEW)
+endif()