Added test case for recently fixed csg normalization bugfix

doc/TODO.txt

@@ -254,8 +254,6 @@ o Caching
   - Test that caching is actually performed (speedup + same results)
   - Test the modifier characters correctly influence the cache (also when
     added/removed)
-o CSG normalization
-  - Empty top-level intersection
 o other tests
   - export
   - cmd-line tests

testdata/scad/bugs/intersection-prune-test.scad

@@ -0,0 +1,9 @@
+// This tree cannot be pruned inline, but will still result in an empty CSG tree
+// Crashes OpenSCAD-2011.12. Bug fixed in 14e4f3bb
+intersection() {
+ union() {
+  cube();
+  translate([4,0,0]) cube();
+ }
+ translate([2,0,0]) cube();
+}

tests/CMakeLists.txt

@@ -619,6 +619,7 @@ list(APPEND CGALPNGTEST_FILES ${CMAKE_SOURCE_DIR}/../testdata/scad/misc/include-
                            ${CMAKE_SOURCE_DIR}/../testdata/scad/misc/use-tests.scad)
 list(APPEND OPENCSGTEST_FILES ${CGALPNGTEST_FILES})
 list(APPEND OPENCSGTEST_FILES ${CMAKE_SOURCE_DIR}/../testdata/scad/bugs/bbox-transform-bug.scad)
+list(APPEND OPENCSGTEST_FILES ${CMAKE_SOURCE_DIR}/../testdata/scad/bugs/intersection-prune-test.scad)
 list(APPEND THROWNTOGETHERTEST_FILES ${OPENCSGTEST_FILES})
 
 list(APPEND CGALSTLSANITYTEST_FILES ${CMAKE_SOURCE_DIR}/../testdata/scad/misc/normal-nan.scad)