Wasm2c fuzz support: only emit a call to the hang limit function if present (#2977)

It may not be present while reducing a testcase, if the reducer removed it.

1 files changed, 21 insertions, 0 deletions

diff --git a/test/unit/test_wasm2c.py b/test/unit/test_wasm2c.py
new file mode 100644
index 000000000..bcdab355b
--- /dev/null
+++ b/test/unit/test_wasm2c.py
@@ -0,0 +1,21 @@
+from scripts.test import shared
+from . import utils
+
+
+class Wasm2CTest(utils.BinaryenTestCase):
+    def test_wrapper(self):
+        # the wrapper C code should only call the hang limit initializer if
+        # that is present.
+        empty_wasm = self.input_path('empty.wasm')
+        args = [empty_wasm, '--emit-wasm2c-wrapper=output.c']
+        shared.run_process(shared.WASM_OPT + args)
+        with open('output.c') as f:
+            normal_output = f.read()
+        # running with ttf generates a new wasm for fuzzing, which always
+        # includes the hang limit initializer function
+        shared.run_process(shared.WASM_OPT + args + ['-ttf'])
+        with open('output.c') as f:
+            ttf_output = f.read()
+        hang_limit_name = 'hangLimitInitializer'
+        self.assertIn(hang_limit_name, ttf_output)
+        self.assertNotIn(hang_limit_name, normal_output)