Merge pull request #5138 from tchaikov/kafka/proto/defaulted-operator-eq

kafka/protocol: use default generated operator==()

src/v/kafka/protocol/api_versions.h

@@ -58,36 +58,8 @@ struct api_versions_response final {
 
 private:
     friend bool operator==(
-      const kafka::api_versions_response& a,
-      const kafka::api_versions_response& b) {
-        return a.data.error_code == b.data.error_code
-               && a.data.throttle_time_ms == b.data.throttle_time_ms
-               && a.data.finalized_features_epoch
-                    == b.data.finalized_features_epoch
-               && a.data.api_keys == b.data.api_keys
-               && a.data.supported_features == b.data.supported_features
-               && a.data.finalized_features == b.data.finalized_features;
-    }
+      const kafka::api_versions_response&, const kafka::api_versions_response&)
+      = default;
 };
 
-inline bool operator==(
-  const api_versions_response_key& a, const api_versions_response_key& b) {
-    return a.api_key == b.api_key && a.min_version == b.min_version
-           && a.max_version == b.max_version;
-}
-
-inline bool operator==(
-  const kafka::supported_feature_key& a,
-  const kafka::supported_feature_key& b) {
-    return a.name == b.name && a.min_version == b.min_version
-           && a.max_version == b.max_version;
-}
-
-inline bool operator==(
-  const kafka::finalized_feature_key& a,
-  const kafka::finalized_feature_key& b) {
-    return a.name == b.name && a.max_version_level == b.max_version_level
-           && a.min_version_level == b.min_version_level;
-}
-
 } // namespace kafka

src/v/kafka/protocol/schemata/generator.py

@@ -33,7 +33,6 @@
 #   make it easier to audit where sensitive information is used.
 import io
 import json
-import functools
 import pathlib
 import re
 import sys
@@ -437,6 +436,13 @@ def make_context_field(path):
     "FinalizedFeatureKey",
 ]
 
+# a list of struct types which are ineligible to have default-generated
+# `operator==()`, because one or more of its member variables are not
+# comparable
+WITHOUT_DEFAULT_EQUALITY_OPERATOR = {
+    'kafka::batch_reader', 'kafka::produce_request_record_data'
+}
+
 # The following is a list of tag types which contain fields where their
 # respective types are not prefixed with []. The generator special cases these
 # as ArrayTypes
@@ -634,6 +640,10 @@ def structs(self):
                 res.append(t)
         return res
 
+    @property
+    def is_default_comparable(self):
+        return all(field.is_default_comparable for field in self.fields)
+
 
 class ArrayType(FieldType):
     def __init__(self, value_type):
@@ -845,6 +855,11 @@ def value_type(self):
     def name(self):
         return snake_case(self._field["name"])
 
+    @property
+    def is_default_comparable(self):
+        type_name, _ = self._redpanda_type()
+        return type_name not in WITHOUT_DEFAULT_EQUALITY_OPERATOR
+
 
 HEADER_TEMPLATE = """
 #pragma once
@@ -894,6 +909,9 @@ def name(self):
     // added by redpanda. see generator.py:make_context_field.
     {{ struct.context_field[0] }} {{ struct.context_field[1] -}};
 {%- endif %}
+{%- if struct.is_default_comparable %}
+    friend bool operator==(const {{ struct.name }}&, const {{ struct.name }}&) = default;
+{%- endif %}
 {% endmacro %}
 
 namespace kafka {