Move optional metadata field so its not last (#2909)

To avoid the conditional trailing comma.

35 files changed, 84 insertions, 75 deletions

diff --git a/scripts/test/lld.py b/scripts/test/lld.py
index 1407ea4b7..5732f7332 100644
--- a/scripts/test/lld.py
+++ b/scripts/test/lld.py
@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import json
 import os
 from . import shared
 from . import support
@@ -43,18 +44,26 @@ def run_test(input_path):
         })
     for ext, args in extension_arg_map.items():
         expected_file = input_path + ext
-        if ext != '.out' and not os.path.exists(expected_file):
-            continue
+        if not os.path.exists(expected_file):
+            if ext == '.out':
+                shared.fail_with_error('output ' + expected_file +
+                                       ' does not exist')
+            else:
+                continue
 
         cmd = shared.WASM_EMSCRIPTEN_FINALIZE + [input_path, '-S'] + args
         cmd += args_for_finalize(os.path.basename(input_path))
         actual = support.run_command(cmd)
 
-        if not os.path.exists(expected_file):
-            print(actual)
-            shared.fail_with_error('output ' + expected_file +
-                                   ' does not exist')
         shared.fail_if_not_identical_to_file(actual, expected_file)
+        if ext == '.out':
+            start = actual.find('--BEGIN METADATA --\n')
+            end = actual.find('-- END METADATA --\n')
+            if start == -1 or end == -1:
+                shared.fail_with_error('json metadata tags not found')
+            the_json = actual[start + len('--BEGIN METADATA --\n'):end]
+            json.loads(the_json)
+
         if ext == '.mem.out':
             with open(mem_file) as mf:
                 mem = mf.read()
diff --git a/src/wasm/wasm-emscripten.cpp b/src/wasm/wasm-emscripten.cpp
index a57573254..4a8f2c0c3 100644
--- a/src/wasm/wasm-emscripten.cpp
+++ b/src/wasm/wasm-emscripten.cpp
@@ -1217,13 +1217,6 @@ std::string EmscriptenGlueGenerator::generateEmscriptenMetadata(
   });
   meta << "\n  ],\n";
 
-  meta << "  \"features\": [";
-  commaFirst = true;
-  wasm.features.iterFeatures([&](FeatureSet::Feature f) {
-    meta << nextElement() << "\"--enable-" << FeatureSet::toString(f) << '"';
-  });
-  meta << "\n  ],\n";
-
   // In normal mode we attempt to determine if main takes argumnts or not
   // In standalone mode we export _start instead and rely on the presence
   // of the __wasi_args_get and __wasi_args_sizes_get syscalls allow us to
@@ -1247,9 +1240,16 @@ std::string EmscriptenGlueGenerator::generateEmscriptenMetadata(
         }
       }
     }
-    meta << "  \"mainReadsParams\": " << int(mainReadsParams) << '\n';
+    meta << "  \"mainReadsParams\": " << int(mainReadsParams) << ",\n";
   }
 
+  meta << "  \"features\": [";
+  commaFirst = true;
+  wasm.features.iterFeatures([&](FeatureSet::Feature f) {
+    meta << nextElement() << "\"--enable-" << FeatureSet::toString(f) << '"';
+  });
+  meta << "\n  ]\n";
+
   meta << "}\n";
 
   return meta.str();
diff --git a/test/lld/basic_safe_stack.wat.out b/test/lld/basic_safe_stack.wat.out
index 525a31ef2..a72f3d215 100644
--- a/test/lld/basic_safe_stack.wat.out
+++ b/test/lld/basic_safe_stack.wat.out
@@ -102,9 +102,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 1,
   "features": [
-  ],
-  "mainReadsParams": 1
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/bigint.wat.out b/test/lld/bigint.wat.out
index 44146d07d..d45da9dea 100644
--- a/test/lld/bigint.wat.out
+++ b/test/lld/bigint.wat.out
@@ -42,9 +42,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/duplicate_imports.wat.out b/test/lld/duplicate_imports.wat.out
index 6493137e9..2163841ed 100644
--- a/test/lld/duplicate_imports.wat.out
+++ b/test/lld/duplicate_imports.wat.out
@@ -77,9 +77,9 @@
   "invokeFuncs": [
     "invoke_ffd"
   ],
+  "mainReadsParams": 1,
   "features": [
-  ],
-  "mainReadsParams": 1
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/em_asm.wat.mem.out b/test/lld/em_asm.wat.mem.out
index 96346d374..c840be861 100644
--- a/test/lld/em_asm.wat.mem.out
+++ b/test/lld/em_asm.wat.mem.out
@@ -100,9 +100,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/em_asm.wat.out b/test/lld/em_asm.wat.out
index 68d1be09d..64cf00069 100644
--- a/test/lld/em_asm.wat.out
+++ b/test/lld/em_asm.wat.out
@@ -101,9 +101,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/em_asm_O0.wat.out b/test/lld/em_asm_O0.wat.out
index 232f0fa9d..f68965876 100644
--- a/test/lld/em_asm_O0.wat.out
+++ b/test/lld/em_asm_O0.wat.out
@@ -82,9 +82,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 1,
   "features": [
-  ],
-  "mainReadsParams": 1
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/em_asm_main_thread.wat.out b/test/lld/em_asm_main_thread.wat.out
index d20895833..e6acc68d4 100644
--- a/test/lld/em_asm_main_thread.wat.out
+++ b/test/lld/em_asm_main_thread.wat.out
@@ -224,9 +224,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/em_asm_shared.wat.out b/test/lld/em_asm_shared.wat.out
index 4126a1abb..8819abed3 100644
--- a/test/lld/em_asm_shared.wat.out
+++ b/test/lld/em_asm_shared.wat.out
@@ -144,9 +144,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/em_asm_table.wat.out b/test/lld/em_asm_table.wat.out
index 9f01b5b7f..024298055 100644
--- a/test/lld/em_asm_table.wat.out
+++ b/test/lld/em_asm_table.wat.out
@@ -56,9 +56,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/em_js_O0.wat.out b/test/lld/em_js_O0.wat.out
index 8b5f3024e..af048242e 100644
--- a/test/lld/em_js_O0.wat.out
+++ b/test/lld/em_js_O0.wat.out
@@ -37,9 +37,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/gdollar_mainmodule.wat.out b/test/lld/gdollar_mainmodule.wat.out
index b7a55efb1..cbefc6c47 100644
--- a/test/lld/gdollar_mainmodule.wat.out
+++ b/test/lld/gdollar_mainmodule.wat.out
@@ -73,9 +73,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 1,
   "features": [
-  ],
-  "mainReadsParams": 1
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/hello_world.passive.wat.out b/test/lld/hello_world.passive.wat.out
index 097a2de94..ab580104f 100644
--- a/test/lld/hello_world.passive.wat.out
+++ b/test/lld/hello_world.passive.wat.out
@@ -67,9 +67,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/hello_world.wat.mem.out b/test/lld/hello_world.wat.mem.out
index 0df58bb99..cdd378f72 100644
--- a/test/lld/hello_world.wat.mem.out
+++ b/test/lld/hello_world.wat.mem.out
@@ -56,9 +56,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/hello_world.wat.out b/test/lld/hello_world.wat.out
index f78baa05f..c33b0ff70 100644
--- a/test/lld/hello_world.wat.out
+++ b/test/lld/hello_world.wat.out
@@ -57,9 +57,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/init.wat.out b/test/lld/init.wat.out
index 32ae0dbc3..d5a3b8b81 100644
--- a/test/lld/init.wat.out
+++ b/test/lld/init.wat.out
@@ -69,9 +69,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/longjmp.wat.out b/test/lld/longjmp.wat.out
index 78ac95fe0..97c391ad0 100644
--- a/test/lld/longjmp.wat.out
+++ b/test/lld/longjmp.wat.out
@@ -177,9 +177,9 @@
   "invokeFuncs": [
     "invoke_vii"
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/main_module.wat.out b/test/lld/main_module.wat.out
index 826b58fa3..4169c9693 100644
--- a/test/lld/main_module.wat.out
+++ b/test/lld/main_module.wat.out
@@ -117,9 +117,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/main_module_table.wat.out b/test/lld/main_module_table.wat.out
index 08f3e6508..3f3c7ee10 100644
--- a/test/lld/main_module_table.wat.out
+++ b/test/lld/main_module_table.wat.out
@@ -61,9 +61,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/main_module_table_2.wat.out b/test/lld/main_module_table_2.wat.out
index df14789f0..af92e7ea2 100644
--- a/test/lld/main_module_table_2.wat.out
+++ b/test/lld/main_module_table_2.wat.out
@@ -61,9 +61,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/main_module_table_3.wat.out b/test/lld/main_module_table_3.wat.out
index d473959bc..2df18b7b3 100644
--- a/test/lld/main_module_table_3.wat.out
+++ b/test/lld/main_module_table_3.wat.out
@@ -61,9 +61,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/main_module_table_4.wat.out b/test/lld/main_module_table_4.wat.out
index fd78f9237..221864563 100644
--- a/test/lld/main_module_table_4.wat.out
+++ b/test/lld/main_module_table_4.wat.out
@@ -61,9 +61,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/main_module_table_5.wat.out b/test/lld/main_module_table_5.wat.out
index 01bb7ffaf..32a089127 100644
--- a/test/lld/main_module_table_5.wat.out
+++ b/test/lld/main_module_table_5.wat.out
@@ -67,9 +67,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/recursive.wat.out b/test/lld/recursive.wat.out
index eb0f04321..0e118dc13 100644
--- a/test/lld/recursive.wat.out
+++ b/test/lld/recursive.wat.out
@@ -115,9 +115,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/recursive_safe_stack.wat.out b/test/lld/recursive_safe_stack.wat.out
index d5a5d6303..b84820e09 100644
--- a/test/lld/recursive_safe_stack.wat.out
+++ b/test/lld/recursive_safe_stack.wat.out
@@ -177,9 +177,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/reserved_func_ptr.wat.out b/test/lld/reserved_func_ptr.wat.out
index 20ad96bf5..1ec059701 100644
--- a/test/lld/reserved_func_ptr.wat.out
+++ b/test/lld/reserved_func_ptr.wat.out
@@ -150,9 +150,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 1,
   "features": [
-  ],
-  "mainReadsParams": 1
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/safe_stack_standalone-wasm.wat.out b/test/lld/safe_stack_standalone-wasm.wat.out
index 81f62a0dd..a7b828a03 100644
--- a/test/lld/safe_stack_standalone-wasm.wat.out
+++ b/test/lld/safe_stack_standalone-wasm.wat.out
@@ -186,7 +186,7 @@
   "invokeFuncs": [
   ],
   "features": [
-  ],
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/shared.wat.out b/test/lld/shared.wat.out
index 973902149..f83855f3b 100644
--- a/test/lld/shared.wat.out
+++ b/test/lld/shared.wat.out
@@ -93,9 +93,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/shared_add_to_table.wasm.out b/test/lld/shared_add_to_table.wasm.out
index e64e031a9..26c0fa7af 100644
--- a/test/lld/shared_add_to_table.wasm.out
+++ b/test/lld/shared_add_to_table.wasm.out
@@ -118,9 +118,9 @@
   },
   "invokeFuncs": [
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/shared_longjmp.wat.out b/test/lld/shared_longjmp.wat.out
index eda443edc..4e6589f4a 100644
--- a/test/lld/shared_longjmp.wat.out
+++ b/test/lld/shared_longjmp.wat.out
@@ -198,9 +198,9 @@
   "invokeFuncs": [
     "invoke_vii"
   ],
+  "mainReadsParams": 0,
   "features": [
-  ],
-  "mainReadsParams": 0
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/standalone-wasm-with-start.wat.out b/test/lld/standalone-wasm-with-start.wat.out
index 367a26168..d463d0bfb 100644
--- a/test/lld/standalone-wasm-with-start.wat.out
+++ b/test/lld/standalone-wasm-with-start.wat.out
@@ -44,7 +44,7 @@
   "invokeFuncs": [
   ],
   "features": [
-  ],
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/standalone-wasm.wat.out b/test/lld/standalone-wasm.wat.out
index 3a483bdf7..3d1137fab 100644
--- a/test/lld/standalone-wasm.wat.out
+++ b/test/lld/standalone-wasm.wat.out
@@ -59,7 +59,7 @@
   "invokeFuncs": [
   ],
   "features": [
-  ],
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/standalone-wasm2.wat.out b/test/lld/standalone-wasm2.wat.out
index d6a0c5505..8700e2844 100644
--- a/test/lld/standalone-wasm2.wat.out
+++ b/test/lld/standalone-wasm2.wat.out
@@ -56,7 +56,7 @@
   "invokeFuncs": [
   ],
   "features": [
-  ],
+  ]
 }
 -- END METADATA --
 ;)
diff --git a/test/lld/standalone-wasm3.wat.out b/test/lld/standalone-wasm3.wat.out
index 65557a790..b0db5cb77 100644
--- a/test/lld/standalone-wasm3.wat.out
+++ b/test/lld/standalone-wasm3.wat.out
@@ -37,7 +37,7 @@
   "invokeFuncs": [
   ],
   "features": [
-  ],
+  ]
 }
 -- END METADATA --
 ;)