CMake: Provide WASM compile, link flags to test_lpython

Also provide --exp-wasm-bigint flag in CI

Author: ubaidsk

.github/workflows/CI.yml

@@ -193,7 +193,7 @@ jobs:
             source $HOME/ext/emsdk/emsdk_env.sh # Activate Emscripten
             which node
             node -v
-            node src/lpython/tests/test_lpython.js
+            node --experimental-wasm-bigint src/lpython/tests/test_lpython.js
 
   test_pip_pkgs:
     name: Test PIP Installable Packages

src/lpython/tests/CMakeLists.txt

@@ -32,6 +32,14 @@ endif()
 # Add one main test suite for LPython, composed of many individual cpp files:
 add_executable(test_lpython ${SRC})
 target_link_libraries(test_lpython lpython_lib p::doctest)
+if (HAVE_BUILD_TO_WASM)
+    set(WASM_COMPILE_FLAGS "-g0 -fexceptions")
+    set(WASM_LINK_FLAGS
+      "-Oz -g0 -fexceptions -Wall -Wextra -s ASSERTIONS -s ALLOW_MEMORY_GROWTH=1 -s WASM_BIGINT"
+    )
+    set_target_properties(test_lpython PROPERTIES COMPILE_FLAGS ${WASM_COMPILE_FLAGS})
+    set_target_properties(test_lpython PROPERTIES LINK_FLAGS ${WASM_LINK_FLAGS})
+endif()
 add_test(test_lpython ${PROJECT_BINARY_DIR}/test_lpython)
 
 set_target_properties(test_lpython PROPERTIES