find_*: Add support for option NO_CACHE

Request that find result is stored in a normal variable rather than a
cache entry.

Fixes: #20687
Issue: #20743

3 files changed, 149 insertions, 0 deletions

diff --git a/Tests/RunCMake/find_program/NO_CACHE-stdout.txt b/Tests/RunCMake/find_program/NO_CACHE-stdout.txt
new file mode 100644
index 0000000..c235d81
--- /dev/null
+++ b/Tests/RunCMake/find_program/NO_CACHE-stdout.txt
@@ -0,0 +1,18 @@
+-- PROG_A='.+/Tests/RunCMake/find_program/A/testA'
+-- PROG_AandB='PROG_AandB-NOTFOUND'
+--[ ]+
+-- Policy CMP0125 = OLD
+-- CACHED PROG_cache='unknown'
+-- PROG_cache='unknown'
+-- CACHED PROG_cache='testA'
+-- PROG_cache='testA'
+-- CACHED PROG_cache='testA'
+-- PROG_cache='testA'
+--[ ]+
+-- Policy CMP0125 = NEW
+-- CACHED PROG_cache='unknown'
+-- PROG_cache='unknown'
+-- CACHED PROG_cache='testA'
+-- PROG_cache='testA'
+-- CACHED PROG_cache='testA'
+-- PROG_cache='.+/Tests/RunCMake/find_program/NO_CACHE-build/testA'
diff --git a/Tests/RunCMake/find_program/NO_CACHE.cmake b/Tests/RunCMake/find_program/NO_CACHE.cmake
new file mode 100644
index 0000000..77a0582
--- /dev/null
+++ b/Tests/RunCMake/find_program/NO_CACHE.cmake
@@ -0,0 +1,130 @@
+find_program(PROG_A
+  NAMES testA
+  PATHS ${CMAKE_CURRENT_SOURCE_DIR}/A
+  NO_CACHE
+  NO_DEFAULT_PATH
+  )
+if (DEFINED CACHE{PROG_A})
+  message(SEND_ERROR "Cache variable defined: PROG_A")
+endif()
+message(STATUS "PROG_A='${PROG_A}'")
+
+
+find_program(PROG_AandB
+  NAMES testAandB
+  NO_CACHE
+  )
+if (DEFINED CACHE{PROG_AandB})
+  message(SEND_ERROR "Cache variable defined: PROG_AandN")
+endif()
+message(STATUS "PROG_AandB='${PROG_AandB}'")
+
+
+cmake_policy(SET CMP0125 OLD)
+message(STATUS "")
+message(STATUS "Policy CMP0125 = OLD")
+file(REMOVE "${CMAKE_BINARY_DIR}/testA")
+
+set(PROG_cache "unknown" CACHE FILEPATH "")
+find_program(PROG_cache
+  NAMES testA
+  PATHS ${CMAKE_CURRENT_SOURCE_DIR}/A
+  NO_CACHE
+  NO_DEFAULT_PATH
+  )
+if (NOT DEFINED CACHE{PROG_cache})
+  message(SEND_ERROR "Cache variable not defined: PROG_cache")
+endif()
+message(STATUS "CACHED PROG_cache='$CACHE{PROG_cache}'")
+unset(PROG_cache CACHE)
+message(STATUS "PROG_cache='${PROG_cache}'")
+
+
+set(PROG_cache "testA" CACHE FILEPATH "")
+unset(PROG_cache)
+find_program(PROG_cache
+  NAMES testA
+  PATHS ${CMAKE_CURRENT_SOURCE_DIR}/A
+  NO_CACHE
+  NO_DEFAULT_PATH
+  )
+if (NOT DEFINED CACHE{PROG_cache})
+  message(SEND_ERROR "Cache variable not defined: PROG_cache")
+endif()
+message(STATUS "CACHED PROG_cache='$CACHE{PROG_cache}'")
+unset(PROG_cache CACHE)
+message(STATUS "PROG_cache='${PROG_cache}'")
+
+
+set(PROG_cache "testA" CACHE FILEPATH "")
+unset(PROG_cache)
+# simulate cache variable defined in command line
+file(COPY "${CMAKE_CURRENT_SOURCE_DIR}/A/testA" DESTINATION "${CMAKE_BINARY_DIR}")
+set_property(CACHE PROG_cache PROPERTY TYPE UNINITIALIZED)
+find_program(PROG_cache
+  NAMES testA
+  PATHS ${CMAKE_CURRENT_SOURCE_DIR}/A
+  NO_CACHE
+  NO_DEFAULT_PATH
+  )
+if (NOT DEFINED CACHE{PROG_cache})
+  message(SEND_ERROR "Cache variable not defined: PROG_cache")
+endif()
+message(STATUS "CACHED PROG_cache='$CACHE{PROG_cache}'")
+unset(PROG_cache CACHE)
+message(STATUS "PROG_cache='${PROG_cache}'")
+
+
+cmake_policy(SET CMP0125 NEW)
+message(STATUS "")
+message(STATUS "Policy CMP0125 = NEW")
+file(REMOVE "${CMAKE_BINARY_DIR}/testA")
+
+set(PROG_cache "unknown" CACHE FILEPATH "")
+find_program(PROG_cache
+  NAMES testA
+  PATHS ${CMAKE_CURRENT_SOURCE_DIR}/A
+  NO_CACHE
+  NO_DEFAULT_PATH
+  )
+if (NOT DEFINED CACHE{PROG_cache})
+  message(SEND_ERROR "Cache variable not defined: PROG_cache")
+endif()
+message(STATUS "CACHED PROG_cache='$CACHE{PROG_cache}'")
+unset(PROG_cache CACHE)
+message(STATUS "PROG_cache='${PROG_cache}'")
+
+
+set(PROG_cache "testA" CACHE FILEPATH "")
+unset(PROG_cache)
+find_program(PROG_cache
+  NAMES testA
+  PATHS ${CMAKE_CURRENT_SOURCE_DIR}/A
+  NO_CACHE
+  NO_DEFAULT_PATH
+  )
+if (NOT DEFINED CACHE{PROG_cache})
+  message(SEND_ERROR "Cache variable not defined: PROG_cache")
+endif()
+message(STATUS "CACHED PROG_cache='$CACHE{PROG_cache}'")
+unset(PROG_cache CACHE)
+message(STATUS "PROG_cache='${PROG_cache}'")
+
+
+set(PROG_cache "testA" CACHE FILEPATH "")
+unset(PROG_cache)
+# simulate cache variable defined in command line
+file(COPY "${CMAKE_CURRENT_SOURCE_DIR}/A/testA" DESTINATION "${CMAKE_BINARY_DIR}")
+set_property(CACHE PROG_cache PROPERTY TYPE UNINITIALIZED)
+find_program(PROG_cache
+  NAMES testA
+  PATHS ${CMAKE_CURRENT_SOURCE_DIR}/A
+  NO_CACHE
+  NO_DEFAULT_PATH
+  )
+if (NOT DEFINED CACHE{PROG_cache})
+  message(SEND_ERROR "Cache variable not defined: PROG_cache")
+endif()
+message(STATUS "CACHED PROG_cache='$CACHE{PROG_cache}'")
+unset(PROG_cache CACHE)
+message(STATUS "PROG_cache='${PROG_cache}'")
diff --git a/Tests/RunCMake/find_program/RunCMakeTest.cmake b/Tests/RunCMake/find_program/RunCMakeTest.cmake
index 77c021d..34edc19 100644
--- a/Tests/RunCMake/find_program/RunCMakeTest.cmake
+++ b/Tests/RunCMake/find_program/RunCMakeTest.cmake
@@ -5,6 +5,7 @@ run_cmake(DirsPerName)
 run_cmake(NamesPerDir)
 run_cmake(RelAndAbsPath)
 run_cmake(Required)
+run_cmake(NO_CACHE)
 
 if(CMAKE_SYSTEM_NAME MATCHES "^(Windows|CYGWIN|MSYS)$")
   run_cmake(WindowsCom)