Teach BuildDepends test to cover LINK_DEPENDS_NO_SHARED

Build a shared library and an executable linking to it inside the inner
test.  Set LINK_DEPENDS_NO_SHARED on the executable.  Add a custom
target to compare the output file times.  Verify that on the first build
the executable is newer than the library.  Then modify a library source
file.  Verify that on the second build the library is newer because the
executable did not have a dependency to re-link.

Tests/BuildDepends/CMakeLists.txt

@@ -60,6 +60,12 @@ file(WRITE ${BuildDepends_BINARY_DIR}/Project/zot_macro_dir.hxx
 file(WRITE ${BuildDepends_BINARY_DIR}/Project/zot_macro_tgt.hxx
   "static const char* zot_macro_tgt = \"zot_macro_tgt\";\n")
 
+file(WRITE ${BuildDepends_BINARY_DIR}/Project/link_depends_no_shared_lib.h
+  "#define link_depends_no_shared_lib_value 1\n")
+file(WRITE ${BuildDepends_BINARY_DIR}/Project/link_depends_no_shared_exe.h
+  "#define link_depends_no_shared_exe_value 0\n")
+set(link_depends_no_shared_check_txt ${BuildDepends_BINARY_DIR}/Project/link_depends_no_shared_check.txt)
+
 help_xcode_depends()
 
 message("Building project first time")
@@ -125,6 +131,19 @@ else()
   message(SEND_ERROR "Project did not initially build properly: ${out}")
 endif()
 
+if(EXISTS "${link_depends_no_shared_check_txt}")
+  file(STRINGS "${link_depends_no_shared_check_txt}" link_depends_no_shared_check LIMIT_COUNT 1)
+  if("${link_depends_no_shared_check}" STREQUAL "1")
+    message(STATUS "link_depends_no_shared_exe is newer than link_depends_no_shared_lib as expected.")
+  else()
+    message(SEND_ERROR "Project did not initially build properly: "
+      "link_depends_no_shared_exe is older than link_depends_no_shared_lib.")
+  endif()
+else()
+  message(SEND_ERROR "Project did not initially build properly: "
+    "Targets link_depends_no_shared_lib and link_depends_no_shared_exe not both built.")
+endif()
+
 message("Waiting 3 seconds...")
 # any additional argument will cause ${bar} to wait forever
 execute_process(COMMAND ${bar} -infinite TIMEOUT 3 OUTPUT_VARIABLE out)
@@ -141,6 +160,9 @@ file(WRITE ${BuildDepends_BINARY_DIR}/Project/zot_macro_dir.hxx
 file(WRITE ${BuildDepends_BINARY_DIR}/Project/zot_macro_tgt.hxx
   "static const char* zot_macro_tgt = \"zot_macro_tgt changed\";\n")
 
+file(WRITE ${BuildDepends_BINARY_DIR}/Project/link_depends_no_shared_lib.h
+  "#define link_depends_no_shared_lib_value 0\n")
+
 if(TEST_LINK_DEPENDS)
   file(WRITE ${TEST_LINK_DEPENDS} "2")
 endif()
@@ -219,3 +241,15 @@ is not newer than dependency
 ")
   endif()
 endif()
+
+if(EXISTS "${link_depends_no_shared_check_txt}")
+  file(STRINGS "${link_depends_no_shared_check_txt}" link_depends_no_shared_check LIMIT_COUNT 1)
+  if("${link_depends_no_shared_check}" STREQUAL "0")
+    message(STATUS "link_depends_no_shared_exe is older than link_depends_no_shared_lib as expected.")
+  else()
+    message(SEND_ERROR "Project did not rebuild properly: link_depends_no_shared_exe is newer than link_depends_no_shared_lib.")
+  endif()
+else()
+  message(SEND_ERROR "Project did not rebuild properly.  "
+    "Targets link_depends_no_shared_lib and link_depends_no_shared_exe not both built.")
+endif()

Tests/BuildDepends/Project/CMakeLists.txt

@@ -107,3 +107,18 @@ if(TEST_LINK_DEPENDS)
   add_executable(linkdep linkdep.cxx)
   set_property(TARGET linkdep PROPERTY LINK_DEPENDS ${TEST_LINK_DEPENDS})
 endif()
+
+add_library(link_depends_no_shared_lib SHARED link_depends_no_shared_lib.c
+  ${CMAKE_CURRENT_BINARY_DIR}/link_depends_no_shared_lib.h)
+add_executable(link_depends_no_shared_exe link_depends_no_shared_exe.c
+  ${CMAKE_CURRENT_BINARY_DIR}/link_depends_no_shared_exe.h)
+target_link_libraries(link_depends_no_shared_exe link_depends_no_shared_lib)
+set_property(TARGET link_depends_no_shared_exe PROPERTY LINK_DEPENDS_NO_SHARED 1)
+add_custom_target(link_depends_no_shared_check ALL
+  COMMAND ${CMAKE_COMMAND}
+   -Dlib=$<TARGET_FILE:link_depends_no_shared_lib>
+   -Dexe=$<TARGET_FILE:link_depends_no_shared_exe>
+   -Dout=${CMAKE_CURRENT_BINARY_DIR}/link_depends_no_shared_check.txt
+   -P ${CMAKE_CURRENT_SOURCE_DIR}/link_depends_no_shared_check.cmake
+  )
+add_dependencies(link_depends_no_shared_check link_depends_no_shared_exe)

Tests/BuildDepends/Project/link_depends_no_shared_check.cmake

@@ -0,0 +1,7 @@
+if(NOT EXISTS "${lib}" OR NOT EXISTS "${exe}")
+  file(REMOVE "${out}")
+elseif("${exe}" IS_NEWER_THAN "${lib}")
+  file(WRITE "${out}" "1\n")
+else()
+  file(WRITE "${out}" "0\n")
+endif()

Tests/BuildDepends/Project/link_depends_no_shared_exe.c

@@ -0,0 +1,9 @@
+#include "link_depends_no_shared_exe.h"
+#ifdef _WIN32
+__declspec(dllimport)
+#endif
+int link_depends_no_shared_lib(void);
+int main()
+{
+  return link_depends_no_shared_lib() + link_depends_no_shared_exe_value;
+}

Tests/BuildDepends/Project/link_depends_no_shared_lib.c

@@ -0,0 +1,8 @@
+#include "link_depends_no_shared_lib.h"
+#ifdef _WIN32
+__declspec(dllexport)
+#endif
+int link_depends_no_shared_lib(void)
+{
+  return link_depends_no_shared_lib_value;
+}