diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index ddce7e0f..a4021923 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -44,7 +44,7 @@ if(JSON_Coverage)
     # (filter script from https://stackoverflow.com/a/43726240/266378)
     add_custom_target(lcov_html
         COMMAND lcov --directory . --capture --output-file json.info --gcov-tool ${GCOV_BIN} --rc lcov_branch_coverage=1
-        COMMAND lcov -e json.info ${CMAKE_SOURCE_DIR}/src/json.hpp --output-file json.info.filtered --rc lcov_branch_coverage=1
+        COMMAND lcov -e json.info ${CMAKE_SOURCE_DIR}/single_include/nlohmann/json.hpp --output-file json.info.filtered --rc lcov_branch_coverage=1
         COMMAND ${CMAKE_SOURCE_DIR}/test/thirdparty/imapdl/filterbr.py json.info.filtered > json.info.filtered.noexcept
         COMMAND genhtml --title "JSON for Modern C++" --legend --demangle-cpp --output-directory html --show-details --branch-coverage json.info.filtered.noexcept
         COMMENT "Generating HTML report test/html/index.html"