[Rust] get proper version for composite types. (#1058)

Co-authored-by: marcio.andrade <[email protected]>

Author: marciorasf

build.gradle

@@ -672,6 +672,7 @@ tasks.register('generateRustTestCodecs', JavaExec) {
             'sbe-tool/src/test/resources/issue984.xml',
             'sbe-tool/src/test/resources/issue987.xml',
             'sbe-tool/src/test/resources/issue1028.xml',
+            'sbe-tool/src/test/resources/issue1057.xml',
             'sbe-tool/src/test/resources/fixed-sized-primitive-array-types.xml',
             'sbe-tool/src/test/resources/example-bigendian-test-schema.xml',
             'sbe-tool/src/test/resources/nested-composite-name.xml',

rust/Cargo.toml

@@ -17,6 +17,7 @@ issue_972 = { path = "../generated/rust/issue972" }
 issue_984 = { path = "../generated/rust/issue984" }
 issue_987 = { path = "../generated/rust/issue987" }
 issue_1028 = { path = "../generated/rust/issue1028" }
+issue_1057 = { path = "../generated/rust/issue1057" }
 baseline_bigendian = { path = "../generated/rust/baseline-bigendian" }
 nested_composite_name = { path = "../generated/rust/nested-composite-name" }
 fixed_sized_primitive_array = { path = "../generated/rust/fixed_sized_primitive_array" }

sbe-tool/src/main/java/uk/co/real_logic/sbe/generation/rust/RustGenerator.java

@@ -1686,7 +1686,9 @@ private static void generateCompositeDecoder(
         indent(out, 2, "offset: usize,\n");
         indent(out, 1, "}\n\n");
 
-        final int version = tokens.get(1).version(); // skip BEGIN_COMPOSITE
+        // The version of the composite type is the greatest version of its fields.
+        final int version = tokens.stream().mapToInt(Token::version).max().orElse(0);
+
         appendImplReaderForComposite(schemaVersionType, version, out, 1, decoderName);
 
         // impl<'a, P> start

sbe-tool/src/test/resources/issue1057.xml

@@ -0,0 +1,32 @@
+<sbe:messageSchema
+    xmlns:ns2="http://www.fixprotocol.org/ns/simple/1.0"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xmlns:sbe="http://fixprotocol.io/2016/sbe"
+    package="issue1057"
+    id="1057"
+    version="4"
+    semanticVersion="8.2.3"
+    description="B3 Binary Entrypoint FIXP messages"
+    byteOrder="littleEndian"
+    xsi:schemaLocation="http://fixprotocol.io/2016/sbe sbe.xsd">
+  <types>
+    <set name="EventIndicator" encodingType="uint8" description="Set of indicators for a given event. First use case: indicates possible retransmission of message during recovery process." sinceVersion="4">
+      <choice name="PossResend" description="1=Message is sent during recovery process, 0=Normal message.">0</choice>
+    </set>
+    <type name="SessionID" primitiveType="uint32" semanticType="Int" description="Client connection identification on the gateway assigned by B3."/>
+    <composite name="messageHeader" description="Message identifiers and length of message root.">
+      <type name="blockLength" primitiveType="uint16" description="Length of the root of the FIX message contained before repeating groups or variable/conditions fields."/>
+      <type name="templateId" primitiveType="uint16" description="Template ID used to encode the message."/>
+      <type name="schemaId" primitiveType="uint16" description="ID of the system publishing the message."/>
+      <type name="version" primitiveType="uint16" description="Schema version."/>
+    </composite>
+    <composite name="OutboundBusinessHeader" description="Header used for outbound business messages.">
+      <ref name="sessionID" type="SessionID"/>
+      <ref name="eventIndicator" type="EventIndicator" sinceVersion="4"/>
+    </composite>
+  </types>
+
+  <sbe:message name="ExecutionReport_New" id="200" description="Execution Report - New message is sent in response to a NewOrderSingle or SimpleNewOrder messages, or also from a restated iceberg order.">
+    <field name="businessHeader" type="OutboundBusinessHeader" id="35524" description="Common header to all outbound business messages."/>
+  </sbe:message>
+</sbe:messageSchema>