source_group: ensure that passed file is not a directory

Fixes: #19769

3 files changed, 43 insertions, 5 deletions

diff --git a/Source/cmSourceGroupCommand.cxx b/Source/cmSourceGroupCommand.cxx
index 3a13e57..cc62952 100644
--- a/Source/cmSourceGroupCommand.cxx
+++ b/Source/cmSourceGroupCommand.cxx
@@ -78,10 +78,18 @@ std::vector<std::string> prepareFilesPathsForTree(
   for (auto const& filePath : filesPaths) {
     std::string fullPath =
       cmSystemTools::CollapseFullPath(filePath, currentSourceDir);
-    // If provided file path is actually not a file, silently ignore it.
-    if (cmSystemTools::FileExists(fullPath, /*isFile=*/true)) {
-      prepared.emplace_back(std::move(fullPath));
+    // If provided file path is actually not a directory, silently ignore it.
+    if (cmSystemTools::FileIsDirectory(fullPath)) {
+      continue;
     }
+
+    // Handle directory that doesn't exist yet.
+    if (!fullPath.empty() &&
+        (fullPath.back() == '/' || fullPath.back() == '\\')) {
+      continue;
+    }
+
+    prepared.emplace_back(std::move(fullPath));
   }
 
   return prepared;
diff --git a/Tests/RunCMake/VS10Project/SourceGroupTreeCMakeLists-check.cmake b/Tests/RunCMake/VS10Project/SourceGroupTreeCMakeLists-check.cmake
index 655120a..ee0c412 100644
--- a/Tests/RunCMake/VS10Project/SourceGroupTreeCMakeLists-check.cmake
+++ b/Tests/RunCMake/VS10Project/SourceGroupTreeCMakeLists-check.cmake
@@ -13,6 +13,7 @@ include(${RunCMake_TEST_SOURCE_DIR}/SourceGroupHelpers.cmake)
 set(SOURCE_GROUPS_TO_FIND
   "Dir"
   "Dir\\DirNested"
+  "Generated"
   "SourcesPrefix"
   "SourcesPrefix\\PrefixedNested"
 )
diff --git a/Tests/RunCMake/VS10Project/SourceGroupTreeCMakeLists.cmake b/Tests/RunCMake/VS10Project/SourceGroupTreeCMakeLists.cmake
index 83c87a9..7655e60 100644
--- a/Tests/RunCMake/VS10Project/SourceGroupTreeCMakeLists.cmake
+++ b/Tests/RunCMake/VS10Project/SourceGroupTreeCMakeLists.cmake
@@ -1,16 +1,45 @@
 set(CMAKE_CONFIGURATION_TYPES Debug)
 
+# Test regular tree grouping.
 set(SRC_FILES
   ${CMAKE_CURRENT_SOURCE_DIR}/Dir/foo.cpp
   ${CMAKE_CURRENT_SOURCE_DIR}/Dir/DirNested/foo_nested.cpp
 )
 
+source_group(TREE ${CMAKE_CURRENT_SOURCE_DIR} FILES ${SRC_FILES})
+
+
+# Test files that are not present at configuration time.
+set(GENERATED_SRC_FILES
+  ${CMAKE_CURRENT_BINARY_DIR}/Generated/generated.cpp
+)
+
+file(MAKE_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/Generated)
+
+if(WIN32)
+  add_custom_command(OUTPUT ${GENERATED_SRC_FILES}
+    COMMAND echo. 2>${CMAKE_CURRENT_BINARY_DIR}\\Generated\\generated.cpp
+  )
+else()
+  add_custom_command(OUTPUT ${GENERATED_SRC_FILES}
+    COMMAND touch ${CMAKE_CURRENT_BINARY_DIR}/Generated/generated.cpp
+  )
+endif()
+
+source_group(TREE ${CMAKE_CURRENT_BINARY_DIR} FILES ${GENERATED_SRC_FILES})
+
+
+# Test prefixed tree grouping.
 set(PREFIXED_SRC_FILES
   ${CMAKE_CURRENT_SOURCE_DIR}/Prefixed/bar.cpp
   ${CMAKE_CURRENT_SOURCE_DIR}/Prefixed/PrefixedNested/bar_nested.cpp
 )
 
-add_custom_target(SourceGroupTree SOURCES ${SRC_FILES} ${PREFIXED_SRC_FILES})
+add_custom_target(SourceGroupTree
+  SOURCES
+    ${SRC_FILES}
+    ${GENERATED_SRC_FILES}
+    ${PREFIXED_SRC_FILES}
+)
 
-source_group(TREE ${CMAKE_CURRENT_SOURCE_DIR} FILES ${SRC_FILES})
 source_group(TREE ${CMAKE_CURRENT_SOURCE_DIR}/Prefixed PREFIX SourcesPrefix FILES ${PREFIXED_SRC_FILES})