CMake fixes (#2966)

* cc_binaries should not be tests

This will keep more involved benchmarks from extending test time
unreasonably.

* Fix target_link_libraries conformance with CMP0023

Avoid mixing keyword and non-keyword forms of target_link_libraries.

* Set target_include_directories to PRIVATE for cc_binary and cc_test

* Set add_sources to private

Fixes a warning about policy CMP0076, which wants to make sources
relative if they're public.

* Enable @rpath by default

This silences warnings about policy CMP0042, which we don't care much
about since we don't have install targets.

* Disable griping about undeclared byproducts

... when using the Ninja generator. In our case the undeclared outputs
come from dependencies and we'd need to fix them before we can adopt the
new policy here.

Author: wilhuff

CMakeLists.txt

@@ -16,12 +16,30 @@
 
 cmake_minimum_required(VERSION 2.8.11)
 
+# Disallow mixing keyword and non-keyword forms of target_link_libraries
+if(POLICY CMP0023)
+  cmake_policy(SET CMP0023 NEW)
+endif()
+
 # Report AppleClang separately from Clang. Their version numbers are different.
 # https://cmake.org/cmake/help/v3.0/policy/CMP0025.html
 if(POLICY CMP0025)
   cmake_policy(SET CMP0025 NEW)
 endif()
 
+# Enable rpath by default
+if(POLICY CMP0042)
+  cmake_policy(SET CMP0042 NEW)
+endif()
+
+# Generate Ninja phony rules for unknown dependencies in the build tree and
+# don't complain about doing so. Our dependencies aren't good about declaring
+# BYPRODUCTS and we mix them all into a single uber build so we can't enable
+# this policy until all dependencies are capable of doing so.
+if(POLICY CMP0058)
+  cmake_policy(SET CMP0058 OLD)
+endif()
+
 # Defer enabling any languages.
 project(firebase NONE)
 

Firestore/core/test/firebase/firestore/objc/CMakeLists.txt

@@ -23,7 +23,7 @@ cc_test(
 
 if(APPLE)
   target_sources(
-    firebase_firestore_objc_test PUBLIC
+    firebase_firestore_objc_test PRIVATE
     objc_class_test.cc
     objc_class_test_helper.h
     objc_class_test_helper.mm

cmake/cc_rules.cmake

@@ -128,10 +128,9 @@ function(cc_binary name)
   maybe_remove_objc_sources(sources ${ccb_SOURCES})
   add_executable(${name} ${sources})
   add_objc_flags(${name} ${ccb_SOURCES})
-  add_test(${name} ${name})
 
-  target_include_directories(${name} PUBLIC ${FIREBASE_SOURCE_DIR})
-  target_link_libraries(${name} ${ccb_DEPENDS})
+  target_include_directories(${name} PRIVATE ${FIREBASE_SOURCE_DIR})
+  target_link_libraries(${name} PRIVATE ${ccb_DEPENDS})
 
   if(ccb_EXCLUDE_FROM_ALL)
     set_property(
@@ -160,8 +159,8 @@ function(cc_test name)
   add_objc_flags(${name} ${cct_SOURCES})
   add_test(${name} ${name})
 
-  target_include_directories(${name} PUBLIC ${FIREBASE_SOURCE_DIR})
-  target_link_libraries(${name} ${cct_DEPENDS})
+  target_include_directories(${name} PRIVATE ${FIREBASE_SOURCE_DIR})
+  target_link_libraries(${name} PRIVATE ${cct_DEPENDS})
 endfunction()
 
 # cc_fuzz_test(