GenEx: Test early determination of AND and OR

It should be possible for example to do this:

 "$<AND:${FOO},$<BOOL:${TGT}>,$<BOOL:$<TARGET_PROPERTY:${TGT},PROP>"

such that it works simliarly to the C code:

 if (foo && tgt && tgt->prop())
   {
   }

The example of generator expression code is a little bit contrived as
it could be written other ways with the same functionality. Nevertheless,
as these cases already work and are intentional, test for them.

Tests/GeneratorExpression/CMakeLists.txt

@@ -14,6 +14,9 @@ add_custom_target(check ALL
     -Dtest_and_1=$<AND:1>
     -Dtest_and_1_0=$<AND:1,0>
     -Dtest_and_1_1=$<AND:1,1>
+    # Ordinarily, the 'invalidcontent' would cause an error, but
+    # the '0' makes the AND abort early.
+    -Dtest_and_0_invalidcontent=$<AND:0,invalidcontent>
     -Dtest_config_0=$<CONFIG:$<CONFIGURATION>x>
     -Dtest_config_1=$<CONFIG:$<CONFIGURATION>>
     -Dtest_not_0=$<NOT:0>
@@ -24,6 +27,7 @@ add_custom_target(check ALL
     -Dtest_or_1=$<OR:1>
     -Dtest_or_1_0=$<OR:1,0>
     -Dtest_or_1_1=$<OR:1,1>
+    -Dtest_or_1_invalidcontent=$<OR:1,invalidcontent>
     -Dtest_bool_notfound=$<BOOL:NOTFOUND>
     -Dtest_bool_foo_notfound=$<BOOL:Foo-NOTFOUND>
     -Dtest_bool_true=$<BOOL:True>

Tests/GeneratorExpression/check.cmake

@@ -15,6 +15,7 @@ check(test_and_0_1 "0")
 check(test_and_1 "1")
 check(test_and_1_0 "0")
 check(test_and_1_1 "1")
+check(test_and_0_invalidcontent "0")
 check(test_config_0 "0")
 check(test_config_1 "1")
 check(test_not_0 "1")
@@ -25,6 +26,7 @@ check(test_or_0_1 "1")
 check(test_or_1 "1")
 check(test_or_1_0 "1")
 check(test_or_1_1 "1")
+check(test_or_1_invalidcontent "1")
 check(test_bool_notfound "0")
 check(test_bool_foo_notfound "0")
 check(test_bool_true "1")

Tests/RunCMake/GeneratorExpression/BadAND-stderr.txt

@@ -39,6 +39,15 @@ CMake Error at BadAND.cmake:1 \(add_custom_target\):
 
     \$<AND:nothing>
 
+  Parameters to \$<AND> must resolve to either '0' or '1'.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)
++
+CMake Error at BadAND.cmake:1 \(add_custom_target\):
+  Error evaluating generator expression:
+
+    \$<AND:1,nothing>
+
   Parameters to \$<AND> must resolve to either '0' or '1'.
 Call Stack \(most recent call first\):
   CMakeLists.txt:3 \(include\)$

Tests/RunCMake/GeneratorExpression/BadAND.cmake

@@ -4,4 +4,5 @@ add_custom_target(check ALL COMMAND check
   $<AND:,>
   $<AND:01>
   $<AND:nothing>
+  $<AND:1,nothing>
   VERBATIM)

Tests/RunCMake/GeneratorExpression/BadOR-stderr.txt

@@ -39,6 +39,15 @@ CMake Error at BadOR.cmake:1 \(add_custom_target\):
 
     \$<OR:nothing>
 
+  Parameters to \$<OR> must resolve to either '0' or '1'.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)
++
+CMake Error at BadOR.cmake:1 \(add_custom_target\):
+  Error evaluating generator expression:
+
+    \$<OR:0,nothing>
+
   Parameters to \$<OR> must resolve to either '0' or '1'.
 Call Stack \(most recent call first\):
   CMakeLists.txt:3 \(include\)$

Tests/RunCMake/GeneratorExpression/BadOR.cmake

@@ -4,4 +4,5 @@ add_custom_target(check ALL COMMAND check
   $<OR:,>
   $<OR:01>
   $<OR:nothing>
+  $<OR:0,nothing>
   VERBATIM)