Xcode: Teach XCODE_ATTRIBUTE target properties about generator expressions

Signed-off-by: Gregor Jasny <gjasny@googlemail.com>

Help/prop_tgt/XCODE_ATTRIBUTE_an-attribute.rst

@@ -8,3 +8,9 @@ the generated Xcode project.  Ignored on other generators.
 
 See the :variable:`CMAKE_XCODE_ATTRIBUTE_<an-attribute>` variable
 to set attributes on all targets in a directory tree.
+
+Contents of ``XCODE_ATTRIBUTE_<an-attribute>`` may use
+"generator expressions" with the syntax ``$<...>``.  See the
+:manual:`cmake-generator-expressions(7)` manual for available
+expressions.  See the :manual:`cmake-buildsystem(7)` manual
+for more on defining buildsystem properties.

Help/release/dev/xcode-attribute-genex.rst

@@ -0,0 +1,5 @@
+xcode-attribute-genex
+---------------------
+
+* The :prop_tgt:`XCODE_ATTRIBUTE_<an-attribute>` target property learned
+  to support generator expressions.

Source/cmGlobalXCodeGenerator.cxx

@@ -2436,8 +2436,11 @@ void cmGlobalXCodeGenerator::CreateBuildSettings(cmTarget& target,
 
       if (!attribute.empty())
         {
+        cmGeneratorExpression ge;
+        std::string processed = ge.Parse(i->second.GetValue())
+          ->Evaluate(this->CurrentMakefile, configName);
         buildSettings->AddAttribute(attribute.c_str(),
-                                    this->CreateString(i->second.GetValue()));
+                                    this->CreateString(processed));
         }
       }
     }

Tests/RunCMake/XcodeProject/RunCMakeTest.cmake

@@ -1,3 +1,5 @@
 include(RunCMake)
 
 run_cmake(XcodeFileType)
+run_cmake(XcodeAttributeGenex)
+run_cmake(XcodeAttributeGenexError)

Tests/RunCMake/XcodeProject/XcodeAttributeGenex-check.cmake

@@ -0,0 +1,7 @@
+set(expect "TEST_HOST = \"[^;\"]*Tests/RunCMake/XcodeProject/XcodeAttributeGenex-build/[^;\"/]*/some\"")
+file(STRINGS ${RunCMake_TEST_BINARY_DIR}/XcodeAttributeGenex.xcodeproj/project.pbxproj actual
+     REGEX "TEST_HOST = .*;" LIMIT_COUNT 1)
+if(NOT "${actual}" MATCHES "${expect}")
+  message(SEND_ERROR "The actual project contains the line:\n ${actual}\n"
+    "which does not match expected regex:\n ${expect}\n")
+endif()

Tests/RunCMake/XcodeProject/XcodeAttributeGenex.cmake

@@ -0,0 +1,4 @@
+enable_language(C)
+add_executable(some main.c)
+add_executable(another main.c)
+set_property(TARGET another PROPERTY XCODE_ATTRIBUTE_TEST_HOST "$<TARGET_FILE:some>")

Tests/RunCMake/XcodeProject/XcodeAttributeGenexError-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/XcodeProject/XcodeAttributeGenexError-stderr.txt

@@ -0,0 +1,6 @@
+CMake Error:
+  Error evaluating generator expression:
+
+    \$<NOTAGENEX>
+
+  Expression did not evaluate to a known generator expression

Tests/RunCMake/XcodeProject/XcodeAttributeGenexError.cmake

@@ -0,0 +1,4 @@
+enable_language(C)
+add_executable(some main.c)
+add_executable(another main.c)
+set_property(TARGET another PROPERTY XCODE_ATTRIBUTE_TEST_HOST "$<NOTAGENEX>")