add document for undocumented error codes

docs/source/error_code_list2.rst

@@ -442,3 +442,77 @@ Example:
         # The following will not generate an error on either
         # Python 3.8, or Python 3.9
         42 + "testing..."  # type: ignore
+
+.. _code-empty-body:
+
+Check that functions have empty body [empty-body]
+-------------------------------------------------------------------
+
+mypy generates an error if you have a function that has an empty body.
+Example:
+
+.. code-block:: python
+
+    # Use "mypy --enable-error-code empty-body ..."
+
+    def f(x: int) -> str:
+        # Error: Function is missing a body
+        pass
+
+.. _code-top-level-await:
+
+Check that your code have top-level await statements [top-level-await]
+----------------------------------------------------------------------
+
+mypy generates an error if you have a top-level await statement.
+
+Example:
+
+.. code-block:: python
+
+
+    import asyncio
+
+    async def f() -> int:
+        return 1
+
+    # Error: "await" used at the top level
+    await f()
+
+.. _code-str-format:
+
+Check that strings have wrong format parameters [str-format]
+------------------------------------------------------------
+
+mypy generates an error if you have a string with wrong format parameters.
+
+Example:
+
+.. code-block:: python
+
+    # Error: More parameters than arguments
+    print("Hello {0} {1}".format("World"))
+
+    # Error: More arguments than parameters
+    print("Hello {0} {1}".format(1, 2, 3))
+
+    # Error: format argument is not type-safe
+    print("%d %d" % ("Hello", "World"))
+
+.. _code-annotation-unchecked:
+
+Check that annotations are inside an unannotated function [annotation-unchecked]
+--------------------------------------------------------------------------------
+
+mypy generates an error to notify that you have annotations which are not checked in an unannotated function.
+
+Consider using --check-untyped-defs option if you want to check unannotated functions as well.
+
+Example:
+
+.. code-block:: python
+
+    def f():
+        x: int = 1
+        # Error: Annotation type "int" is not checked
+        return x