gcovr · Spacetown · Sep 29, 2022 · Aug 7, 2022 · Aug 7, 2022 · Aug 8, 2022
diff --git a/CHANGELOG.rst b/CHANGELOG.rst
@@ -16,6 +16,7 @@ New features and notable changes:
 - New :option:`--json-base` to define a base bath used in JSON reports. (:issue:`656`)
 - New :option:`--calls` to report call coverage: function calls invoked/total (:issue:`666`)
 - New nox session to generate a portable application with pyinstaller, see :ref:`standalone application`. (:issue:`661`)
+- Print a warning if root directory contains symlinks. (:issue:`652`)
 
 Bug fixes and small improvements:
 

diff --git a/gcovr/__main__.py b/gcovr/__main__.py
@@ -255,6 +255,16 @@ def main(args=None):
 
     options.starting_dir = os.path.abspath(os.getcwd())
     options.root_dir = os.path.abspath(options.root)
+    root_dir_realpath = os.path.realpath(options.root_dir)
+    if options.root_dir != root_dir_realpath and not options.filter:
+        logger.warning(
+            "Your project --root directory seems to contain a symlink. "
+            "This will EXCLUDE source files in your root directory! "
+            "To fix this, you may have to add a --filter option:\n"
+            "    --filter='%s'\n"
+            "For details, see https://github.com/gcovr/gcovr/issues/635",
+            re.escape(root_dir_realpath),
+        )
 
     #
     # Setup filters

diff --git a/gcovr/tests/symlink-root/.gitignore b/gcovr/tests/symlink-root/.gitignore
@@ -0,0 +1,4 @@
+root/stdout.log
+
+# Ignore the linked directory
+symlink_root
diff --git a/gcovr/tests/symlink-root/Makefile b/gcovr/tests/symlink-root/Makefile
@@ -0,0 +1,38 @@
+CFLAGS= -fprofile-arcs -ftest-coverage -fPIC
+
+BASE_OS:=$(shell uname | cut -d'-' -f1)
+
+all: links
+	cd symlink; $(CXX) $(CFLAGS) main.cpp -o testcase
+
+run: txt
+
+txt:
+	cd symlink; ./testcase
+	cd symlink; $(GCOVR) --txt ../coverage.txt --root $${PWD} > out.log 2>&1
+	cd symlink; cat out.log
+	cd symlink; grep -F "Your project --root directory seems to contain a symlink." out.log
+
+clean:
+ifeq ($(filter $(BASE_OS),MSYS_NT MINGW64_NT),)
+	rm -Rf symlink
+else
+	if [ -d "symlink" ]; then\
+		cmd.exe /C "rmdir /S /Q symlink";\
+	fi
+endif
+	rm -f root/*.gc* root/coverage*.* root/sonarqube*.* root/coveralls.json root/out.log
+
+links:
+ifeq ($(filter $(BASE_OS),MSYS_NT MINGW64_NT),)
+	if [ -d "symlink" ]; then\
+		rm -Rf symlink;\
+	fi
+	ln -s ./root symlink;
+else
+	if [ -d "symlink" ]; then\
+		cmd.exe /C "rmdir /S /Q symlink";\
+	fi
+	cmd.exe /C "mklink /j symlink .\root"
+endif
+	find ./root -name '*.o' -or -name '*.gc*' -delete || exit 0
diff --git a/gcovr/tests/symlink-root/reference/clang-10/coverage.txt b/gcovr/tests/symlink-root/reference/clang-10/coverage.txt
@@ -0,0 +1,9 @@
+------------------------------------------------------------------------------
+                           GCC Code Coverage Report
+Directory: ../symlink
+------------------------------------------------------------------------------
+File                                       Lines    Exec  Cover   Missing
+------------------------------------------------------------------------------
+------------------------------------------------------------------------------
+TOTAL                                          0       0    --%
+------------------------------------------------------------------------------
diff --git a/gcovr/tests/symlink-root/reference/gcc-5/coverage.txt b/gcovr/tests/symlink-root/reference/gcc-5/coverage.txt
@@ -0,0 +1,9 @@
+------------------------------------------------------------------------------
+                           GCC Code Coverage Report
+Directory: ../symlink
+------------------------------------------------------------------------------
+File                                       Lines    Exec  Cover   Missing
+------------------------------------------------------------------------------
+------------------------------------------------------------------------------
+TOTAL                                          0       0    --%
+------------------------------------------------------------------------------
diff --git a/gcovr/tests/symlink-root/root/main.cpp b/gcovr/tests/symlink-root/root/main.cpp
@@ -0,0 +1,4 @@
+
+int main() {
+	return 0;
+}
diff --git a/gcovr/tests/test_gcovr.py b/gcovr/tests/test_gcovr.py
@@ -271,6 +271,12 @@ def pytest_generate_tests(metafunc):
                     name == "simple1-drive-subst" and not IS_WINDOWS,
                     reason="drive substitution only available on Windows",
                 ),
+                pytest.mark.skipif(
+                    name == "symlink-root"
+                    and IS_WINDOWS
+                    and (sys.version_info < (3, 8)),
+                    reason="os.path.realpath resolves symlinks on windows starting with 3.8",
+                ),
                 pytest.mark.xfail(
                     name == "exclude-throw-branches"
                     and format == "html"