test: check that /var/log got created with the right size

test/test_build.py

@@ -383,12 +383,17 @@ def test_image_boots(image_type):
 
         # Figure out how big / is and make sure it is > 10GiB
         # Note that df output is in 1k blocks, not bytes
+        found_var_log = False
         for line in output.splitlines():
             fields = line.split()
             if fields[0] == "/sysroot":
                 size = int(fields[1])
                 assert size > 10 * 1024 * 1024
-                break
+            elif fields[0] == "/var/log":
+                size = int(fields[1])
+                assert size == 1 * 1024 * 1024
+                found_var_log
+        assert found_var_log, f"no /var/log mount found in {output}"
 
 
 @pytest.mark.parametrize("image_type", gen_testcases("ami-boot"), indirect=["image_type"])