cmTarget: Allow transitive evaluation of SOURCES property.

Extend the cmGeneratorExpressionDAGChecker with an interface
returning the name of the top target.  Use that to determine
when there is a DAG violation, as required by the RunCMake.Languages
tests.

5 files changed, 27 insertions, 1 deletions

diff --git a/Tests/ConfigSources/CMakeLists.txt b/Tests/ConfigSources/CMakeLists.txt
index 68a4233..c272257 100644
--- a/Tests/ConfigSources/CMakeLists.txt
+++ b/Tests/ConfigSources/CMakeLists.txt
@@ -3,7 +3,15 @@ cmake_minimum_required(VERSION 3.0)
 
 project(ConfigSources)
 
+add_library(iface INTERFACE)
+set_property(TARGET iface PROPERTY INTERFACE_SOURCES
+  iface_src.cpp
+  $<$<CONFIG:Debug>:iface_debug_src.cpp>
+  $<$<CONFIG:Release>:does_not_exist.cpp>
+)
+
 add_executable(ConfigSources
   $<$<CONFIG:Debug>:main.cpp>
   $<$<CONFIG:Release>:does_not_exist.cpp>
 )
+target_link_libraries(ConfigSources iface)
diff --git a/Tests/ConfigSources/iface_debug.h b/Tests/ConfigSources/iface_debug.h
new file mode 100644
index 0000000..a23d737
--- /dev/null
+++ b/Tests/ConfigSources/iface_debug.h
@@ -0,0 +1,4 @@
+
+int iface_src();
+
+int iface_debug();
diff --git a/Tests/ConfigSources/iface_debug_src.cpp b/Tests/ConfigSources/iface_debug_src.cpp
new file mode 100644
index 0000000..63b22fc
--- /dev/null
+++ b/Tests/ConfigSources/iface_debug_src.cpp
@@ -0,0 +1,7 @@
+
+#include "iface_debug.h"
+
+int iface_debug()
+{
+  return 0;
+}
diff --git a/Tests/ConfigSources/iface_src.cpp b/Tests/ConfigSources/iface_src.cpp
new file mode 100644
index 0000000..c3a0c8f
--- /dev/null
+++ b/Tests/ConfigSources/iface_src.cpp
@@ -0,0 +1,5 @@
+
+int iface_src()
+{
+  return 0;
+}
diff --git a/Tests/ConfigSources/main.cpp b/Tests/ConfigSources/main.cpp
index 1c19e8d..71af72f 100644
--- a/Tests/ConfigSources/main.cpp
+++ b/Tests/ConfigSources/main.cpp
@@ -1,5 +1,7 @@
 
+#include "iface_debug.h"
+
 int main(int argc, char** argv)
 {
-  return 0;
+  return iface_src() + iface_debug();
 }