Add deprecation warnings for policies CMP0126 and below

The OLD behaviors of all policies are deprecated, but only by
documentation.  Add an explicit deprecation diagnostic for policies
introduced in CMake 3.21 and below to encourage projects to port
away from setting policies to OLD.

12 files changed, 97 insertions, 5 deletions

diff --git a/Source/cmMakefile.cxx b/Source/cmMakefile.cxx
index 80f8a77..40d769d 100644
--- a/Source/cmMakefile.cxx
+++ b/Source/cmMakefile.cxx
@@ -4630,12 +4630,13 @@ bool cmMakefile::SetPolicy(cmPolicies::PolicyID id,
   }
 
   // Deprecate old policies.
-  if (status == cmPolicies::OLD && id <= cmPolicies::CMP0120 &&
+  if (status == cmPolicies::OLD && id <= cmPolicies::CMP0126 &&
       !(this->GetCMakeInstance()->GetIsInTryCompile() &&
         (
           // Policies set by cmCoreTryCompile::TryCompileCode.
           id == cmPolicies::CMP0065 || id == cmPolicies::CMP0083 ||
-          id == cmPolicies::CMP0091 || id == cmPolicies::CMP0104)) &&
+          id == cmPolicies::CMP0091 || id == cmPolicies::CMP0104 ||
+          id == cmPolicies::CMP0123 || id == cmPolicies::CMP0126)) &&
       (!this->IsSet("CMAKE_WARN_DEPRECATED") ||
        this->IsOn("CMAKE_WARN_DEPRECATED"))) {
     this->IssueMessage(MessageType::DEPRECATION_WARNING,
diff --git a/Tests/RunCMake/CMP0126/CMP0126-OLD-stderr.txt b/Tests/RunCMake/CMP0126/CMP0126-OLD-stderr.txt
new file mode 100644
index 0000000..7d2608b
--- /dev/null
+++ b/Tests/RunCMake/CMP0126/CMP0126-OLD-stderr.txt
@@ -0,0 +1,10 @@
+^CMake Deprecation Warning at CMP0126-OLD\.cmake:[0-9]+ \(cmake_policy\):
+  The OLD behavior for policy CMP0126 will be removed from a future version
+  of CMake\.
+
+  The cmake-policies\(7\) manual explains that the OLD behaviors of all
+  policies are deprecated and that a policy should be set to OLD only under
+  specific short-term circumstances\.  Projects should be ported to the NEW
+  behavior and not rely on setting a policy to OLD\.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)$
diff --git a/Tests/RunCMake/CMP0126/CMP0126-OLD_CL-stderr.txt b/Tests/RunCMake/CMP0126/CMP0126-OLD_CL-stderr.txt
new file mode 100644
index 0000000..1f2179c
--- /dev/null
+++ b/Tests/RunCMake/CMP0126/CMP0126-OLD_CL-stderr.txt
@@ -0,0 +1,10 @@
+^CMake Deprecation Warning at CMP0126-OLD_CL\.cmake:[0-9]+ \(cmake_policy\):
+  The OLD behavior for policy CMP0126 will be removed from a future version
+  of CMake\.
+
+  The cmake-policies\(7\) manual explains that the OLD behaviors of all
+  policies are deprecated and that a policy should be set to OLD only under
+  specific short-term circumstances\.  Projects should be ported to the NEW
+  behavior and not rely on setting a policy to OLD\.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)$
diff --git a/Tests/RunCMake/ToolchainFile/CMP0126-OLD-stderr.txt b/Tests/RunCMake/ToolchainFile/CMP0126-OLD-stderr.txt
index f3c068a..efa7b32 100644
--- a/Tests/RunCMake/ToolchainFile/CMP0126-OLD-stderr.txt
+++ b/Tests/RunCMake/ToolchainFile/CMP0126-OLD-stderr.txt
@@ -1 +1,12 @@
-^try_compile CMP0126='OLD' VAR='2'
+^CMake Deprecation Warning at CMP0126-OLD\.cmake:[0-9]+ \(cmake_policy\):
+  The OLD behavior for policy CMP0126 will be removed from a future version
+  of CMake\.
+
+  The cmake-policies\(7\) manual explains that the OLD behaviors of all
+  policies are deprecated and that a policy should be set to OLD only under
+  specific short-term circumstances\.  Projects should be ported to the NEW
+  behavior and not rely on setting a policy to OLD\.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)
++
+try_compile CMP0126='OLD' VAR='2'
diff --git a/Tests/RunCMake/UseSWIG/CMP0122-NEW-check.cmake b/Tests/RunCMake/UseSWIG/CMP0122-NEW-check.cmake
index a26c278..df14d15 100644
--- a/Tests/RunCMake/UseSWIG/CMP0122-NEW-check.cmake
+++ b/Tests/RunCMake/UseSWIG/CMP0122-NEW-check.cmake
@@ -1,5 +1,5 @@
 
-cmake_policy(VERSION 3.1)
+cmake_policy(VERSION 3.5)
 
 file(STRINGS "${RunCMake_TEST_BINARY_DIR}/CMP0122-library-name.txt" prefixes)
 
diff --git a/Tests/RunCMake/UseSWIG/CMP0122-OLD-check.cmake b/Tests/RunCMake/UseSWIG/CMP0122-OLD-check.cmake
index 01657d0..6eb5c20 100644
--- a/Tests/RunCMake/UseSWIG/CMP0122-OLD-check.cmake
+++ b/Tests/RunCMake/UseSWIG/CMP0122-OLD-check.cmake
@@ -1,5 +1,5 @@
 
-cmake_policy(VERSION 3.1)
+cmake_policy(VERSION 3.5)
 
 file(STRINGS "${RunCMake_TEST_BINARY_DIR}/CMP0122-library-name.txt" prefixes)
 
diff --git a/Tests/RunCMake/UseSWIG/CMP0122-OLD-stderr.txt b/Tests/RunCMake/UseSWIG/CMP0122-OLD-stderr.txt
new file mode 100644
index 0000000..84f2ee7
--- /dev/null
+++ b/Tests/RunCMake/UseSWIG/CMP0122-OLD-stderr.txt
@@ -0,0 +1,10 @@
+^CMake Deprecation Warning at CMP0122-OLD\.cmake:[0-9]+ \(cmake_policy\):
+  The OLD behavior for policy CMP0122 will be removed from a future version
+  of CMake\.
+
+  The cmake-policies\(7\) manual explains that the OLD behaviors of all
+  policies are deprecated and that a policy should be set to OLD only under
+  specific short-term circumstances\.  Projects should be ported to the NEW
+  behavior and not rely on setting a policy to OLD\.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)$
diff --git a/Tests/RunCMake/find_file/NO_CACHE-stderr.txt b/Tests/RunCMake/find_file/NO_CACHE-stderr.txt
new file mode 100644
index 0000000..6da353b
--- /dev/null
+++ b/Tests/RunCMake/find_file/NO_CACHE-stderr.txt
@@ -0,0 +1,10 @@
+^CMake Deprecation Warning at NO_CACHE\.cmake:[0-9]+ \(cmake_policy\):
+  The OLD behavior for policy CMP0125 will be removed from a future version
+  of CMake\.
+
+  The cmake-policies\(7\) manual explains that the OLD behaviors of all
+  policies are deprecated and that a policy should be set to OLD only under
+  specific short-term circumstances\.  Projects should be ported to the NEW
+  behavior and not rely on setting a policy to OLD\.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)
diff --git a/Tests/RunCMake/find_library/NO_CACHE-stderr.txt b/Tests/RunCMake/find_library/NO_CACHE-stderr.txt
new file mode 100644
index 0000000..6da353b
--- /dev/null
+++ b/Tests/RunCMake/find_library/NO_CACHE-stderr.txt
@@ -0,0 +1,10 @@
+^CMake Deprecation Warning at NO_CACHE\.cmake:[0-9]+ \(cmake_policy\):
+  The OLD behavior for policy CMP0125 will be removed from a future version
+  of CMake\.
+
+  The cmake-policies\(7\) manual explains that the OLD behaviors of all
+  policies are deprecated and that a policy should be set to OLD only under
+  specific short-term circumstances\.  Projects should be ported to the NEW
+  behavior and not rely on setting a policy to OLD\.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)
diff --git a/Tests/RunCMake/find_path/NO_CACHE-stderr.txt b/Tests/RunCMake/find_path/NO_CACHE-stderr.txt
new file mode 100644
index 0000000..6da353b
--- /dev/null
+++ b/Tests/RunCMake/find_path/NO_CACHE-stderr.txt
@@ -0,0 +1,10 @@
+^CMake Deprecation Warning at NO_CACHE\.cmake:[0-9]+ \(cmake_policy\):
+  The OLD behavior for policy CMP0125 will be removed from a future version
+  of CMake\.
+
+  The cmake-policies\(7\) manual explains that the OLD behaviors of all
+  policies are deprecated and that a policy should be set to OLD only under
+  specific short-term circumstances\.  Projects should be ported to the NEW
+  behavior and not rely on setting a policy to OLD\.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)
diff --git a/Tests/RunCMake/find_program/NO_CACHE-stderr.txt b/Tests/RunCMake/find_program/NO_CACHE-stderr.txt
new file mode 100644
index 0000000..6da353b
--- /dev/null
+++ b/Tests/RunCMake/find_program/NO_CACHE-stderr.txt
@@ -0,0 +1,10 @@
+^CMake Deprecation Warning at NO_CACHE\.cmake:[0-9]+ \(cmake_policy\):
+  The OLD behavior for policy CMP0125 will be removed from a future version
+  of CMake\.
+
+  The cmake-policies\(7\) manual explains that the OLD behaviors of all
+  policies are deprecated and that a policy should be set to OLD only under
+  specific short-term circumstances\.  Projects should be ported to the NEW
+  behavior and not rely on setting a policy to OLD\.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)
diff --git a/Tests/RunCMake/foreach/foreach-var-scope-CMP0124-OLD-stderr.txt b/Tests/RunCMake/foreach/foreach-var-scope-CMP0124-OLD-stderr.txt
new file mode 100644
index 0000000..7a49647
--- /dev/null
+++ b/Tests/RunCMake/foreach/foreach-var-scope-CMP0124-OLD-stderr.txt
@@ -0,0 +1,10 @@
+^CMake Deprecation Warning at foreach-var-scope-CMP0124-OLD\.cmake:[0-9]+ \(cmake_policy\):
+  The OLD behavior for policy CMP0124 will be removed from a future version
+  of CMake\.
+
+  The cmake-policies\(7\) manual explains that the OLD behaviors of all
+  policies are deprecated and that a policy should be set to OLD only under
+  specific short-term circumstances\.  Projects should be ported to the NEW
+  behavior and not rely on setting a policy to OLD\.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)$