Merge topic 'export-no-custom-target'

7e9f908e export: Reject custom target exports earlier (#15657)
3b09398a Tests: Teach RunCMake.export to enable languages only when needed

Source/cmExportCommand.cxx

@@ -177,6 +177,12 @@ bool cmExportCommand
           this->SetError(e.str());
           return false;
           }
+        if (target->GetType() == cmTarget::UTILITY)
+          {
+          this->SetError("given custom target \"" + *currentTarget
+                         + "\" which may not be exported.");
+          return false;
+          }
         }
       else
         {

Tests/RunCMake/export/AppendExport-stderr.txt

@@ -1,4 +1,4 @@
-CMake Error at AppendExport.cmake:8 \(export\):
+CMake Error at AppendExport.cmake:[0-9]+ \(export\):
   export EXPORT signature does not recognise the APPEND option.
 Call Stack \(most recent call first\):
   CMakeLists.txt:3 \(include\)

Tests/RunCMake/export/AppendExport.cmake

@@ -1,3 +1,4 @@
+enable_language(CXX)
 add_library(foo empty.cpp)
 export(TARGETS foo FILE "${CMAKE_CURRENT_BINARY_DIR}/foo.cmake")
 install(TARGETS foo EXPORT fooExport

Tests/RunCMake/export/CMakeLists.txt

@@ -1,3 +1,3 @@
 cmake_minimum_required(VERSION 2.8.4)
-project(${RunCMake_TEST})
+project(${RunCMake_TEST} NONE)
 include(${RunCMake_TEST}.cmake)

Tests/RunCMake/export/CustomTarget-result.txt

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

Tests/RunCMake/export/CustomTarget-stderr.txt

@@ -0,0 +1,4 @@
+^CMake Error at CustomTarget.cmake:[0-9]+ \(export\):
+  export given custom target "CustomTarget" which may not be exported.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)$

Tests/RunCMake/export/CustomTarget.cmake

@@ -0,0 +1,2 @@
+add_custom_target(CustomTarget)
+export(TARGETS CustomTarget FILE somefile.cmake)

Tests/RunCMake/export/OldIface-stderr.txt

@@ -1,4 +1,4 @@
-CMake Error at OldIface.cmake:8 \(export\):
+CMake Error at OldIface.cmake:[0-9]+ \(export\):
   export EXPORT signature does not recognise the
   EXPORT_LINK_INTERFACE_LIBRARIES option.
 Call Stack \(most recent call first\):

Tests/RunCMake/export/OldIface.cmake

@@ -1,3 +1,4 @@
+enable_language(CXX)
 add_library(foo empty.cpp)
 export(TARGETS foo FILE "${CMAKE_CURRENT_BINARY_DIR}/foo.cmake")
 install(TARGETS foo EXPORT fooExport

Tests/RunCMake/export/RunCMakeTest.cmake

@@ -1,5 +1,6 @@
 include(RunCMake)
 
+run_cmake(CustomTarget)
 run_cmake(TargetNotFound)
 run_cmake(AppendExport)
 run_cmake(OldIface)