diff --git a/scripts/cmake/vcpkg_find_acquire_program(GN).cmake b/scripts/cmake/vcpkg_find_acquire_program(GN).cmake
index eeb025a050cf62..bcf0f9df727eb6 100644
--- a/scripts/cmake/vcpkg_find_acquire_program(GN).cmake
+++ b/scripts/cmake/vcpkg_find_acquire_program(GN).cmake
@@ -4,7 +4,7 @@ if(EXISTS "${CURRENT_HOST_INSTALLED_DIR}/share/gn/version.txt")
     file(READ "${CURRENT_HOST_INSTALLED_DIR}/share/gn/version.txt" program_version)
     set(paths_to_search "${CURRENT_HOST_INSTALLED_DIR}/tools/gn")
 else() # Old behavior
-    message("Consider adding vcpkg-tool-gn as a host dependency of this port or create an issue at https://github.com/microsoft/vcpkg/issues")
+    message(STATUS "Consider adding vcpkg-tool-gn as a host dependency of this port or create an issue at https://github.com/microsoft/vcpkg/issues")
     set(cipd_download_gn "https://chrome-infra-packages.appspot.com/dl/gn/gn")
     if(CMAKE_HOST_SYSTEM_NAME STREQUAL "Linux")
         execute_process(COMMAND uname -m OUTPUT_VARIABLE HOST_ARCH OUTPUT_STRIP_TRAILING_WHITESPACE)
diff --git a/scripts/cmake/vcpkg_find_acquire_program.cmake b/scripts/cmake/vcpkg_find_acquire_program.cmake
index 4dc2c0e169f2ca..442814ee901230 100644
--- a/scripts/cmake/vcpkg_find_acquire_program.cmake
+++ b/scripts/cmake/vcpkg_find_acquire_program.cmake
@@ -49,6 +49,7 @@ function(z_vcpkg_find_acquire_program_find_external program)
         unset(SCRIPT_${arg_PROGRAM_NAME} CACHE)
     endif()
 
+    set(${program} "$CACHE{${program}}")
     if("${version_command}" STREQUAL "")
         set(version_is_good ON) # can't check for the version being good, so assume it is
     elseif(${program}) # only do a version check if ${program} has a value
@@ -60,8 +61,10 @@ function(z_vcpkg_find_acquire_program_find_external program)
         )
     endif()
 
-    if(NOT version_is_good)
-        unset("${program}" PARENT_SCOPE)
+    if(version_is_good)
+        set(${program} "$CACHE{${program}}" PARENT_SCOPE)
+    else()
+        set("${program}" "${program}-NOTFOUND" PARENT_SCOPE)
         unset("${program}" CACHE)
     endif()
 endfunction()
@@ -92,6 +95,7 @@ function(z_vcpkg_find_acquire_program_find_internal program)
         endif()
         unset(SCRIPT_${program} CACHE)
     endif()
+    set(${program} "$CACHE{${program}}" PARENT_SCOPE)
 endfunction()
 
 function(vcpkg_find_acquire_program program)
@@ -140,6 +144,15 @@ function(vcpkg_find_acquire_program program)
         set(search_names "${program_name}")
     endif()
 
+    # Force nested `find_program` to either use the cached variable or
+    # to actually search, regardless of a parent scope variable.
+    # Called functions must change the variable in this scope.
+    if("$CACHE{${program}}" STREQUAL "")
+        set(${program} "NOTFOUND")
+    else()
+        set(${program} "$CACHE{${program}}")
+    endif()
+
     z_vcpkg_find_acquire_program_find_internal("${program}"
         INTERPRETER "${interpreter}"
         PATHS ${paths_to_search}
diff --git a/scripts/test_ports/vcpkg-find-acquire-program/portfile.cmake b/scripts/test_ports/vcpkg-find-acquire-program/portfile.cmake
index d31679c9c49a86..a66d3b0eb721b6 100644
--- a/scripts/test_ports/vcpkg-find-acquire-program/portfile.cmake
+++ b/scripts/test_ports/vcpkg-find-acquire-program/portfile.cmake
@@ -70,3 +70,87 @@ if(missing)
     list(JOIN missing "\n   " missing)
     message(FATAL_ERROR "The following programs do not exist:\n   ${missing}")
 endif()
+
+# The postcondition of `vcpkg_find_acquire_program` is that there is a regular
+# variable of the requested name with a non-false value in the calling scope.
+# 
+# Normally, it searches for the requested program and sets a regular variable
+# in the calling scope. However, it does nothing if a variable with that name
+# is already set to a value which CMake regards as true.
+# In contrast, `find_program` sets a cache variable when the search is run.
+# It does nothing if a variable with the given name is defined with a value
+# of "NOTFOUND" or ending with "-NOTFOUND".
+# The small behavioral differences needs extra attention.
+
+include("${CURRENT_HOST_INSTALLED_DIR}/share/unit-test-cmake/test-macros.cmake")
+
+set(expected_gn "$CACHE{GN}")
+
+# Cache variable is set to trueish value: Early return of vfap with current value.
+unset(GN)
+set(GN "THIS IS CACHED GN" CACHE INTERNAL "")
+unit_test_check_variable_equal([[_vcpkg_find_acquire_program(GN)]] GN "THIS IS CACHED GN")
+
+# Cache variable is NOTFOUNDish or empty value: These values evaluate to false,
+# so a search via vfap should run and yield the expected path.
+unset(GN)
+set(GN "NOTFOUND" CACHE INTERNAL "")
+unit_test_check_variable_equal([[_vcpkg_find_acquire_program(GN)]] GN "${expected_gn}")
+
+unset(GN)
+set(GN "GN-NOTFOUND" CACHE INTERNAL "")
+unit_test_check_variable_equal([[_vcpkg_find_acquire_program(GN)]] GN "${expected_gn}")
+
+unset(GN)
+set(GN "" CACHE INTERNAL "")
+unit_test_check_variable_equal([[_vcpkg_find_acquire_program(GN)]] GN "${expected_gn}")
+
+
+# Regular variable is set to trueish value: Early return of vfap with current value.
+unset(GN CACHE)
+set(GN "THIS IS REGULAR GN")
+unit_test_check_variable_equal([[_vcpkg_find_acquire_program(GN)]] GN "THIS IS REGULAR GN")
+
+# Regular variable is NOTFOUNDish or empty value: These values evaluate to false,
+# so a search via vfap should run and yield the expected path.
+unset(GN CACHE)
+set(GN "NOTFOUND")
+unit_test_check_variable_equal([[_vcpkg_find_acquire_program(GN)]] GN "${expected_gn}")
+
+unset(GN CACHE)
+set(GN "GN-NOTFOUND")
+unit_test_check_variable_equal([[_vcpkg_find_acquire_program(GN)]] GN "${expected_gn}")
+
+unset(GN CACHE)
+set(GN "")
+unit_test_check_variable_equal([[_vcpkg_find_acquire_program(GN)]] GN "${expected_gn}")
+
+# Regular variable is NOTFOUNDish or empty value, and it hides a cache variable:
+# The cache variable takes effect.
+set(GN "THIS IS CACHED GN" CACHE INTERNAL "")
+set(GN "NOTFOUND")
+unit_test_check_variable_equal([[_vcpkg_find_acquire_program(GN)]] GN "THIS IS CACHED GN")
+
+set(GN "THIS IS CACHED GN" CACHE INTERNAL "")
+set(GN "GN-NOTFOUND")
+unit_test_check_variable_equal([[_vcpkg_find_acquire_program(GN)]] GN "THIS IS CACHED GN")
+
+set(GN "THIS IS CACHED GN" CACHE INTERNAL "")
+set(GN "")
+unit_test_check_variable_equal([[_vcpkg_find_acquire_program(GN)]] GN "THIS IS CACHED GN")
+
+set(GN "NOTFOUND" CACHE INTERNAL "")
+set(GN "NOTFOUND")
+unit_test_check_variable_equal([[_vcpkg_find_acquire_program(GN)]] GN "${expected_gn}")
+
+set(GN "CACHED-NOTFOUND" CACHE INTERNAL "")
+set(GN "NOTFOUND")
+unit_test_check_variable_equal([[_vcpkg_find_acquire_program(GN)]] GN "${expected_gn}")
+
+set(GN "" CACHE INTERNAL "")
+set(GN "NOTFOUND")
+unit_test_check_variable_equal([[_vcpkg_find_acquire_program(GN)]] GN "${expected_gn}")
+
+# If vfap cannot find or acquire the requested program, it raises a fatal error.
+unit_test_ensure_fatal_error([[_vcpkg_find_acquire_program(REALLY_NO_SUCH_PROGAM)]])
+
diff --git a/scripts/test_ports/vcpkg-find-acquire-program/vcpkg.json b/scripts/test_ports/vcpkg-find-acquire-program/vcpkg.json
index 0b622ebbbf5470..600b305bee90c9 100644
--- a/scripts/test_ports/vcpkg-find-acquire-program/vcpkg.json
+++ b/scripts/test_ports/vcpkg-find-acquire-program/vcpkg.json
@@ -1,7 +1,9 @@
 {
   "name": "vcpkg-find-acquire-program",
-  "version-string": "0",
-  "port-version": 2,
+  "version-string": "ci",
   "description": "Test port to exercise vcpkg_find_acquire_program",
-  "supports": "native"
+  "supports": "native",
+  "dependencies": [
+    "unit-test-cmake"
+  ]
 }