diff --git a/Tests/CMakeLists.txt b/Tests/CMakeLists.txt
index 57d40ce373..deb338eb97 100644
--- a/Tests/CMakeLists.txt
+++ b/Tests/CMakeLists.txt
@@ -2465,7 +2465,7 @@ if(BUILD_TESTING)
     --build-options
       "-DUNUSED_CLI_VARIABLE=Unused")
   set_tests_properties(WarnUnusedCliUnused PROPERTIES
-    PASS_REGULAR_EXPRESSION "CMake Warning:.*Manually-specified variables were not used by the project:.*  UNUSED_CLI_VARIABLE")
+    PASS_REGULAR_EXPRESSION "CMake Warning \\(unused-cli\\):.*Manually-specified variables were not used by the project:.*  UNUSED_CLI_VARIABLE")
   list(APPEND TEST_BUILD_DIRS "${CMake_BINARY_DIR}/Tests/WarnUnusedCliUnused")
 
   add_test(WarnUnusedCliUsed ${CMAKE_CTEST_COMMAND}
diff --git a/Tests/CMakeTests/MessageTest.cmake.in b/Tests/CMakeTests/MessageTest.cmake.in
index a9833b99c9..4b8489d2b3 100644
--- a/Tests/CMakeTests/MessageTest.cmake.in
+++ b/Tests/CMakeTests/MessageTest.cmake.in
@@ -25,6 +25,6 @@ if(NOT "${err}" MATCHES "CMake Warning at[^\n]*:\r?\n  message-warning")
   message(FATAL_ERROR "message(WARNING) did not appear properly")
 endif()
 
-if(NOT "${err}" MATCHES "CMake Warning \\(dev\\) at[^\n]*:\r?\n  message-author")
+if(NOT "${err}" MATCHES "CMake Warning \\(author\\) at[^\n]*:\r?\n  message-author")
   message(FATAL_ERROR "message(AUTHOR_WARNING) did not appear properly")
 endif()
diff --git a/Tests/ExternalProject/CMakeLists.txt b/Tests/ExternalProject/CMakeLists.txt
index c1a4bae5b5..87f6d1b277 100644
--- a/Tests/ExternalProject/CMakeLists.txt
+++ b/Tests/ExternalProject/CMakeLists.txt
@@ -435,9 +435,10 @@ if(EP_TEST_GIT)
   set_property(TARGET ${proj} PROPERTY FOLDER "GIT")
 
   set(proj TS1-GIT-all-GIT_SUBMODULES-via-CMP0097-OLD)
-  set(CMAKE_WARN_DEPRECATED FALSE) # we are testing CMP0097 OLD behavior
+  cmake_diagnostic(PUSH)
+  cmake_diagnostic(SET CMD_DEPRECATED IGNORE)
   cmake_policy(SET CMP0097 OLD)
-  unset(CMAKE_WARN_DEPRECATED)
+  cmake_diagnostic(POP)
   ExternalProject_Add(${proj}
     GIT_REPOSITORY "${local_git_repo}"
     GIT_SUBMODULES ""
diff --git a/Tests/RunCMake/CMakePresets/ErrorDeprecated-stderr.txt b/Tests/RunCMake/CMakePresets/ErrorDeprecated-stderr.txt
index 964a5042f3..f182d46124 100644
--- a/Tests/RunCMake/CMakePresets/ErrorDeprecated-stderr.txt
+++ b/Tests/RunCMake/CMakePresets/ErrorDeprecated-stderr.txt
@@ -1,4 +1,4 @@
-^CMake Deprecation Error at [^
+^CMake Error \(deprecated\) at [^
 ]*/Tests/RunCMake/CMakePresets/WarningsBase\.cmake:[0-9]+ \(message\):
   Deprecation warning
 Call Stack \(most recent call first\):
diff --git a/Tests/RunCMake/CMakePresets/ErrorDev-stderr.txt b/Tests/RunCMake/CMakePresets/ErrorDev-stderr.txt
index 4537246373..569c364e8f 100644
--- a/Tests/RunCMake/CMakePresets/ErrorDev-stderr.txt
+++ b/Tests/RunCMake/CMakePresets/ErrorDev-stderr.txt
@@ -1,13 +1,13 @@
-^CMake Error \(dev\) at [^
+^CMake Error \(author\) at [^
 ]*/Tests/RunCMake/CMakePresets/WarningsBase\.cmake:[0-9]+ \(message\):
   Dev warning
 Call Stack \(most recent call first\):
   [^
 ]*/Tests/RunCMake/CMakePresets/ErrorDev\.cmake:[0-9]+ \(include\)
   CMakeLists\.txt:[0-9]+ \(include\)
-This error is for project developers\. Use -Wno-error=dev to suppress it\.
+This error is for project developers\.  Use -Wno-error=author to suppress it\.
 
-CMake Deprecation Error at [^
+CMake Error \(deprecated\) at [^
 ]*/Tests/RunCMake/CMakePresets/WarningsBase\.cmake:[0-9]+ \(message\):
   Deprecation warning
 Call Stack \(most recent call first\):
diff --git a/Tests/RunCMake/CMakePresets/ErrorUninitialized-stderr.txt b/Tests/RunCMake/CMakePresets/ErrorUninitialized-stderr.txt
index dd4430f8ca..6d9315ee93 100644
--- a/Tests/RunCMake/CMakePresets/ErrorUninitialized-stderr.txt
+++ b/Tests/RunCMake/CMakePresets/ErrorUninitialized-stderr.txt
@@ -1,4 +1,4 @@
-CMake Warning:
+CMake Warning \(unused-cli\):
   Manually-specified variables were not used by the project:
 
     RunCMake_GENERATOR
diff --git a/Tests/RunCMake/CMakePresets/ErrorUnusedCli-stderr.txt b/Tests/RunCMake/CMakePresets/ErrorUnusedCli-stderr.txt
index 0b479ff59c..676a111c9a 100644
--- a/Tests/RunCMake/CMakePresets/ErrorUnusedCli-stderr.txt
+++ b/Tests/RunCMake/CMakePresets/ErrorUnusedCli-stderr.txt
@@ -1,4 +1,4 @@
-CMake Error:
+CMake Error \(unused-cli\):
   Manually-specified variables were not used by the project:
 
     RunCMake_GENERATOR
diff --git a/Tests/RunCMake/CMakePresets/NoWarningFlags-stderr.txt b/Tests/RunCMake/CMakePresets/NoWarningFlags-stderr.txt
index 3844ad3ba6..6e717ed926 100644
--- a/Tests/RunCMake/CMakePresets/NoWarningFlags-stderr.txt
+++ b/Tests/RunCMake/CMakePresets/NoWarningFlags-stderr.txt
@@ -16,7 +16,7 @@ Call Stack \(most recent call first\):
   CMakeLists\.txt:[0-9]+ \(include\)
 
 
-CMake Warning:
+CMake Warning \(unused-cli\):
   Manually-specified variables were not used by the project:
 
     RunCMake_GENERATOR
diff --git a/Tests/RunCMake/CMakePresets/WarningFlags-stderr.txt b/Tests/RunCMake/CMakePresets/WarningFlags-stderr.txt
index 0ca0c924e9..15da2cdf4e 100644
--- a/Tests/RunCMake/CMakePresets/WarningFlags-stderr.txt
+++ b/Tests/RunCMake/CMakePresets/WarningFlags-stderr.txt
@@ -1,11 +1,11 @@
-^CMake Warning \(author\) at [^
+^CMake Warning \(uninitialized\) at [^
 ]*/Modules/[^/
 ]*:[0-9]+ \([a-zA-Z_][a-zA-Z0-9_]*\):
   uninitialized variable '[^
 ]*'
 Call Stack \(most recent call first\):
-  CMakeLists\.txt:[0-9]+ \(project\)
-This warning is for project developers\.  Use -Wno-author to suppress it\..*
+  CMakeLists\.txt:[0-9]+ \(project\)(
+This warning is for project developers\.  Use -Wno-author to suppress it\.)?.*
 CMake Warning \(author\) at [^
 ]*/Tests/RunCMake/CMakePresets/WarningsBase\.cmake:[0-9]+ \(message\):
   Dev warning
@@ -24,11 +24,11 @@ Call Stack \(most recent call first\):
   CMakeLists\.txt:[0-9]+ \(include\)
 
 
-CMake Warning \(author\) at [^
+CMake Warning \(uninitialized\) at [^
 ]*/Tests/RunCMake/CMakePresets/WarningsBase\.cmake:[0-9]+ \(set\):
   uninitialized variable 'UNINITIALIZED_VARIABLE'
 Call Stack \(most recent call first\):
   [^
 ]*/Tests/RunCMake/CMakePresets/WarningFlags\.cmake:[0-9]+ \(include\)
-  CMakeLists\.txt:[0-9]+ \(include\)
-This warning is for project developers\.  Use -Wno-author to suppress it\.$
+  CMakeLists\.txt:[0-9]+ \(include\)(
+This warning is for project developers\.  Use -Wno-author to suppress it\.)?$
diff --git a/Tests/RunCMake/CommandLine/Werror_author-stderr.txt b/Tests/RunCMake/CommandLine/Werror_author-stderr.txt
index f6fdcd669b..29e0dbfd61 100644
--- a/Tests/RunCMake/CommandLine/Werror_author-stderr.txt
+++ b/Tests/RunCMake/CommandLine/Werror_author-stderr.txt
@@ -1,11 +1,11 @@
-^CMake Error \(dev\) at Werror_author\.cmake:4 \(include\):
+^CMake Error \(author\) at Werror_author\.cmake:4 \(include\):
   include\(\) given empty file name \(ignored\)\.
 Call Stack \(most recent call first\):
   CMakeLists\.txt:[0-9]+ \(include\)
-This error is for project developers\. Use -Wno-error=dev to suppress it\.
+This error is for project developers\.  Use -Wno-error=author to suppress it\.
 
-CMake Error \(dev\) at Werror_author\.cmake:7 \(message\):
+CMake Error \(author\) at Werror_author\.cmake:7 \(message\):
   Some author warning
 Call Stack \(most recent call first\):
   CMakeLists\.txt:[0-9]+ \(include\)
-This error is for project developers\. Use -Wno-error=dev to suppress it\.$
+This error is for project developers\.  Use -Wno-error=author to suppress it\.$
diff --git a/Tests/RunCMake/CommandLine/Werror_deprecated-stderr.txt b/Tests/RunCMake/CommandLine/Werror_deprecated-stderr.txt
index e60b54943a..3bbac473ee 100644
--- a/Tests/RunCMake/CommandLine/Werror_deprecated-stderr.txt
+++ b/Tests/RunCMake/CommandLine/Werror_deprecated-stderr.txt
@@ -1,4 +1,4 @@
-^CMake Deprecation Error at Werror_deprecated\.cmake:1 \(message\):
+^CMake Error \(deprecated\) at Werror_deprecated\.cmake:1 \(message\):
   Some deprecated warning
 Call Stack \(most recent call first\):
   CMakeLists\.txt:[0-9]+ \(include\)
diff --git a/Tests/RunCMake/CommandLine/Wuninitialized-stderr.txt b/Tests/RunCMake/CommandLine/Wuninitialized-stderr.txt
index 9d54750071..9490c81bfa 100644
--- a/Tests/RunCMake/CommandLine/Wuninitialized-stderr.txt
+++ b/Tests/RunCMake/CommandLine/Wuninitialized-stderr.txt
@@ -1,23 +1,23 @@
-CMake Warning \(author\) at Wuninitialized\.cmake:1 \(set\):
+CMake Warning \(uninitialized\) at Wuninitialized\.cmake:1 \(set\):
   uninitialized variable 'NEW_WARN_FROM_NORMAL_CMAKE_FILE_INSIDE_BRACES'
 Call Stack \(most recent call first\):
   CMakeLists\.txt:3 \(include\)
-This warning is for project developers\.  Use -Wno-author to suppress it\.
+(This warning is for project developers\.  Use -Wno-author to suppress it\.)?
 
-CMake Warning \(author\) at Wuninitialized\.cmake:2 \(string\):
+CMake Warning \(uninitialized\) at Wuninitialized\.cmake:2 \(string\):
   uninitialized variable 'NEW_WARN_FROM_STRING_CONFIGURE_INSIDE_BRACES'
 Call Stack \(most recent call first\):
   CMakeLists\.txt:3 \(include\)
-This warning is for project developers\.  Use -Wno-author to suppress it\.
+(This warning is for project developers\.  Use -Wno-author to suppress it\.)?
 
-CMake Warning \(author\) at Wuninitialized\.cmake:4 \(configure_file\):
+CMake Warning \(uninitialized\) at Wuninitialized\.cmake:4 \(configure_file\):
   uninitialized variable 'NEW_WARN_FROM_CONFIGURE_FILE_INSIDE_AT'
 Call Stack \(most recent call first\):
   CMakeLists\.txt:3 \(include\)
-This warning is for project developers\.  Use -Wno-author to suppress it\.
+(This warning is for project developers\.  Use -Wno-author to suppress it\.)?
 
-CMake Warning \(author\) at Wuninitialized\.cmake:5 \(string\):
+CMake Warning \(uninitialized\) at Wuninitialized\.cmake:5 \(string\):
   uninitialized variable 'NEW_WARN_FROM_STRING_CONFIGURE_INSIDE_AT'
 Call Stack \(most recent call first\):
-  CMakeLists\.txt:3 \(include\)
-This warning is for project developers\.  Use -Wno-author to suppress it\.$
+  CMakeLists\.txt:3 \(include\)(
+This warning is for project developers\.  Use -Wno-author to suppress it\.)?$
diff --git a/Tests/RunCMake/ObsoleteQtMacros/AutomocMacro-WARN.cmake b/Tests/RunCMake/ObsoleteQtMacros/AutomocMacro-WARN.cmake
index c0c64a5b74..aea9c5d164 100644
--- a/Tests/RunCMake/ObsoleteQtMacros/AutomocMacro-WARN.cmake
+++ b/Tests/RunCMake/ObsoleteQtMacros/AutomocMacro-WARN.cmake
@@ -1,7 +1,7 @@
 
 find_package(Qt4 REQUIRED)
 
-set(CMAKE_WARN_DEPRECATED 1)
+cmake_diagnostic(SET CMD_DEPRECATED WARN)
 
 add_library(foo SHARED empty.cpp)
 qt4_automoc(foo_moc_srcs empty.cpp)
diff --git a/Tests/RunCMake/ObsoleteQtMacros/UseModulesMacro-WARN.cmake b/Tests/RunCMake/ObsoleteQtMacros/UseModulesMacro-WARN.cmake
index e86a3723be..9bd3cc3d53 100644
--- a/Tests/RunCMake/ObsoleteQtMacros/UseModulesMacro-WARN.cmake
+++ b/Tests/RunCMake/ObsoleteQtMacros/UseModulesMacro-WARN.cmake
@@ -1,7 +1,7 @@
 
 find_package(Qt4 REQUIRED)
 
-set(CMAKE_WARN_DEPRECATED 1)
+cmake_diagnostic(SET CMD_DEPRECATED WARN)
 
 add_library(foo SHARED empty.cpp)
 qt4_use_modules(foo LINK_PRIVATE Core)
diff --git a/Tests/RunCMake/message/RunCMakeTest.cmake b/Tests/RunCMake/message/RunCMakeTest.cmake
index 05dd6a6cbd..786b49baf0 100644
--- a/Tests/RunCMake/message/RunCMakeTest.cmake
+++ b/Tests/RunCMake/message/RunCMakeTest.cmake
@@ -7,17 +7,8 @@ run_cmake(ConfigureLog)
 run_cmake(defaultmessage)
 run_cmake(nomessage)
 run_cmake(message-internal-warning)
-# run_cmake(nomessage-internal-warning)
-run_cmake(warnmessage)
-
-# TODO: We currently do not have a way to change diagnostic state in a way that
-# is visible to internally issued diagnostic. This will be remedied when we
-# switch to the new methods for issuing diagnostics, but for a brief window,
-# this test will only pass if author warnings are disabled by command-line
-# option.
-set(RunCMake_TEST_OPTIONS -Wno-author)
 run_cmake(nomessage-internal-warning)
-unset(RunCMake_TEST_OPTIONS)
+run_cmake(warnmessage)
 
 # Have to explicitly give the command for the working dir to be honored
 set(RunCMake_TEST_COMMAND_WORKING_DIRECTORY /)
diff --git a/Tests/RunCMake/message/errormessage_deprecated-stderr.txt b/Tests/RunCMake/message/errormessage_deprecated-stderr.txt
index 8744f72a90..1ca848b9fe 100644
--- a/Tests/RunCMake/message/errormessage_deprecated-stderr.txt
+++ b/Tests/RunCMake/message/errormessage_deprecated-stderr.txt
@@ -1,4 +1,4 @@
-^CMake Deprecation Error at errormessage_deprecated\.cmake:3 \(message\):
+^CMake Error \(deprecated\) at errormessage_deprecated\.cmake:3 \(message\):
   This is a deprecation error
 Call Stack \(most recent call first\):
   CMakeLists\.txt:3 \(include\)$
diff --git a/Tests/RunCMake/message/errormessage_dev-stderr.txt b/Tests/RunCMake/message/errormessage_dev-stderr.txt
index 2d8075a40a..c55dc793a5 100644
--- a/Tests/RunCMake/message/errormessage_dev-stderr.txt
+++ b/Tests/RunCMake/message/errormessage_dev-stderr.txt
@@ -1,5 +1,5 @@
-^CMake Error \(dev\) at errormessage_dev\.cmake:3 \(message\):
+^CMake Error \(author\) at errormessage_dev\.cmake:3 \(message\):
   This is a author error
 Call Stack \(most recent call first\):
   CMakeLists\.txt:3 \(include\)
-This error is for project developers\. Use -Wno-error=dev to suppress it\.$
+This error is for project developers\.  Use -Wno-error=author to suppress it\.$
diff --git a/Tests/UseSWIG/LegacyConfiguration.cmake b/Tests/UseSWIG/LegacyConfiguration.cmake
index 1acc05a4dc..23e1a64cc0 100644
--- a/Tests/UseSWIG/LegacyConfiguration.cmake
+++ b/Tests/UseSWIG/LegacyConfiguration.cmake
@@ -1,6 +1,6 @@
 
 # Prevent deprecated warnings from new UseSWIG module
-set (CMAKE_WARN_DEPRECATED FALSE)
+cmake_diagnostic(SET CMD_DEPRECATED IGNORE)
 
 find_package(SWIG REQUIRED)
 include(${SWIG_USE_FILE})