[Rust] update how "use declarations" are generated, now deriving Defaults for enums (aeron-io#952)

* Fixed several issues: aeron-io#1: LibRsDef explicitly us crate:: to disambiguate from built in mods like bool aeron-io#2: Added acting_version field to Composite structs to fix compilation errors when using Composite structs. This is an incomplete implementation because the parent doesn't pass the acting_version to the composite because you need to change the signature of wrap(parent, offset) to include the acting_version, so this version just ensures that if the acting_version isn't set on the composite, it disregards the version check. aeron-io#3: fixed primitiveArrayDecoder to return an empty array of the right size if less than version required. * [Rust] removed 'acting_version' field from SubGroup decoder * [Rust] updated RustGenerator::generateEnum() to support derive "Default" instead of generating impl * fixed formatting issue * [Rust] updated how 'use declarations' are generated to prevent "ambiguous glob re-exports" warnings from rust compiler --------- Co-authored-by: Adam Krieg <adam@talostrading.com> Co-authored-by: Michael Ward <mward@drw.com>

Author: 3 people

rust/Cargo.toml

@@ -17,7 +17,7 @@ baseline_bigendian = { path = "../generated/rust/baseline-bigendian" }
 nested_composite_name = { path = "../generated/rust/nested-composite-name" }
 
 [dev-dependencies]
-criterion = "0.3"
+criterion = "0.5"
 
 [[bench]]
 name = "car_benchmark"

rust/benches/car_benchmark.rs

@@ -1,5 +1,6 @@
 use criterion::{black_box, criterion_group, criterion_main, Criterion};
 use examples_uk_co_real_logic_sbe_benchmarks::*;
+use car_codec::encoder::*;
 
 const MANUFACTURER: &[u8] = b"MANUFACTURER";
 const MODEL: &[u8] = b"MODEL";

rust/benches/md_benchmark.rs

@@ -1,5 +1,6 @@
 use criterion::{black_box, criterion_group, criterion_main, Criterion};
 use examples_uk_co_real_logic_sbe_benchmarks_fix::*;
+use market_data_incremental_refresh_trades_codec::encoder::*;
 
 struct State {
  buffer: Vec<u8>,

rust/tests/baseline_test.rs

@@ -2,6 +2,7 @@ use std::fs::File;
 use std::io::prelude::*;
 
 use examples_baseline::*;
+use car_codec::encoder::*;
 
 fn read_sbe_file_generated_from_java_example() -> std::io::Result<Vec<u8>> {
  // Generated by the generateCarExampleDataFile gradle task.

rust/tests/big_endian_test.rs

@@ -1,4 +1,5 @@
 use baseline_bigendian::*;
+use car_codec::encoder::*;
 
 #[test]
 fn big_endian_baseline_example() -> SbeResult<()> {

rust/tests/extension_test.rs

@@ -2,6 +2,7 @@ use std::fs::File;
 use std::io::prelude::*;
 
 use examples_extension::*;
+use car_codec::encoder::*;
 
 fn read_sbe_file_generated_from_java_example() -> std::io::Result<Vec<u8>> {
  // Generated by the generateCarExampleDataFile gradle task.

rust/tests/issue_895_test.rs

@@ -1,10 +1,12 @@
-use ::issue_895::*;
+use issue_895::{
+ issue_895_codec::{decoder::Issue895Decoder, encoder::Issue895Encoder},
+ MessageHeaderDecoder, ReadBuf, SbeResult, WriteBuf, ENCODED_LENGTH, SBE_BLOCK_LENGTH,
+ SBE_SCHEMA_ID, SBE_SCHEMA_VERSION, SBE_TEMPLATE_ID,
+};
 
 fn create_encoder(buffer: &mut Vec<u8>) -> Issue895Encoder {
- let issue_895 = Issue895Encoder::default().wrap(
- WriteBuf::new(buffer.as_mut_slice()),
- ENCODED_LENGTH,
- );
+ let issue_895 =
+ Issue895Encoder::default().wrap(WriteBuf::new(buffer.as_mut_slice()), ENCODED_LENGTH);
  let mut header = issue_895.header(0);
  header.parent().unwrap()
 }
@@ -72,4 +74,4 @@ fn issue_895_double_none() -> SbeResult<()> {
  assert_eq!(None, decoder.optional_double());
 
  Ok(())
-}
+}

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

@@ -81,7 +81,7 @@ void generate() throws IOException
  // add re-export of modules
  for (final String module : modules)
  {
- indent(libRs, 0, "pub use %s::*;\n", toLowerSnakeCase(module));
+ indent(libRs, 0, "pub use crate::%s::*;\n", toLowerSnakeCase(module));
  }
  indent(libRs, 0, "\n");
 

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

@@ -15,6 +15,7 @@
  */
 package uk.co.real_logic.sbe.generation.rust;
 
+import org.agrona.Strings;
 import org.agrona.Verify;
 import org.agrona.generation.OutputManager;
 import uk.co.real_logic.sbe.PrimitiveType;
@@ -119,7 +120,7 @@ public void generate() throws IOException
  indent(writer, 0, "version = \"0.1.0\"\n");
  indent(writer, 0, "authors = [\"sbetool\"]\n");
  indent(writer, 0, "description = \"%s\"\n", ir.description());
- indent(writer, 0, "edition = \"2018\"\n\n");
+ indent(writer, 0, "edition = \"2021\"\n\n");
  indent(writer, 0, "[lib]\n");
  indent(writer, 0, "name = \"%s\"\n", namespace);
  indent(writer, 0, "path = \"src/lib.rs\"\n");
@@ -151,8 +152,8 @@ public void generate() throws IOException
  try (Writer out = outputManager.createOutput(codecModName))
  {
  indent(out, 0, "use crate::*;\n\n");
- indent(out, 0, "pub use encoder::*;\n");
- indent(out, 0, "pub use decoder::*;\n\n");
+ indent(out, 0, "pub use encoder::%sEncoder;\n", formatStructName(msgToken.name()));
+ indent(out, 0, "pub use decoder::%sDecoder;\n\n", formatStructName(msgToken.name()));
  final String blockLengthType = blockLengthType();
  final String templateIdType = rustTypeName(ir.headerStructure().templateIdType());
  final String schemaIdType = rustTypeName(ir.headerStructure().schemaIdType());
@@ -274,7 +275,18 @@ static void generateEncoderGroups(
  final Token numInGroupToken = Generators.findFirst("numInGroup", tokens, index);
  final PrimitiveType numInGroupPrimitiveType = numInGroupToken.encoding().primitiveType();
 
- indent(sb, level, "/// GROUP ENCODER\n");
+ final String description = groupToken.description();
+ if (!Strings.isEmpty(description))
+ {
+ indent(sb, level, "/// GROUP ENCODER (id=%s, description='%s')\n",
+ groupToken.id(), description);
+ }
+ else
+ {
+ indent(sb, level, "/// GROUP ENCODER (id=%s)\n",
+ groupToken.id());
+ }
+
  assert 4 == groupHeaderTokenCount;
  indent(sb, level, "#[inline]\n");
  indent(sb, level, "pub fn %s(self, count: %s, %1$s: %3$s<Self>) -> %3$s<Self> {\n",
@@ -553,7 +565,7 @@ private static void generateCompositeDecoder(
  decoderName,
  decoderTypeName);
 
- indent(sb, level + 1, "if self.acting_version < %d {\n", fieldToken.version());
+ indent(sb, level + 1, "if self.acting_version > 0 && self.acting_version < %d {\n", fieldToken.version());
  indent(sb, level + 2, "return Either::Left(self);\n");
  indent(sb, level + 1, "}\n\n");
 
@@ -587,7 +599,7 @@ private static void generateBitSetDecoder(
 
  if (bitsetToken.version() > 0)
  {
- indent(sb, level + 1, "if self.acting_version < %d {\n", bitsetToken.version());
+ indent(sb, level + 1, "if self.acting_version > 0 && self.acting_version < %d {\n", bitsetToken.version());
  indent(sb, level + 2, "return %s::default();\n", structTypeName);
  indent(sb, level + 1, "}\n\n");
  }
@@ -647,7 +659,7 @@ private static void generatePrimitiveArrayDecoder(
 
  if (fieldToken.version() > 0)
  {
- indent(sb, level + 1, "if self.acting_version < %d {\n", fieldToken.version());
+ indent(sb, level + 1, "if self.acting_version > 0 && self.acting_version < %d {\n", fieldToken.version());
  indent(sb, level + 2, "return [%s; %d];\n", encoding.applicableNullValue(), arrayLength);
  indent(sb, level + 1, "}\n\n");
  }
@@ -756,7 +768,7 @@ private static void generatePrimitiveOptionalDecoder(
 
  if (fieldToken.version() > 0)
  {
- indent(sb, level + 1, "if self.acting_version < %d {\n", fieldToken.version());
+ indent(sb, level + 1, "if self.acting_version > 0 && self.acting_version < %d {\n", fieldToken.version());
  indent(sb, level + 2, "return None;\n");
  indent(sb, level + 1, "}\n\n");
  }
@@ -809,7 +821,7 @@ private static void generatePrimitiveRequiredDecoder(
 
  if (fieldToken.version() > 0)
  {
- indent(sb, level + 1, "if self.acting_version < %d {\n", fieldToken.version());
+ indent(sb, level + 1, "if self.acting_version > 0 && self.acting_version < %d {\n", fieldToken.version());
  indent(sb, level + 2, "return %s;\n",
  generateRustLiteral(encoding.primitiveType(), encoding.applicableNullValue().toString()));
  indent(sb, level + 1, "}\n\n");
@@ -897,9 +909,19 @@ static void generateDecoderGroups(
  i = collectVarData(tokens, i, varData);
 
  final String groupName = decoderName(formatStructName(groupToken.name()));
- indent(sb, level, "/// GROUP DECODER\n");
- assert 4 == groupHeaderTokenCount;
+ final String description = groupToken.description();
+ if (!Strings.isEmpty(description))
+ {
+ indent(sb, level, "/// GROUP DECODER (id=%s, description='%s')\n",
+ groupToken.id(), description);
+ }
+ else
+ {
+ indent(sb, level, "/// GROUP DECODER (id=%s)\n",
+ groupToken.id());
+ }
 
+ assert 4 == groupHeaderTokenCount;
  indent(sb, level, "#[inline]\n");
  if (groupToken.version() > 0)
  {
@@ -910,18 +932,14 @@ static void generateDecoderGroups(
  indent(sb, level + 2, "return None;\n");
  indent(sb, level + 1, "}\n\n");
 
- indent(sb, level + 1, "let acting_version = self.acting_version;\n");
- indent(sb, level + 1, "Some(%s::default().wrap(self, acting_version as usize))\n",
- groupName);
+ indent(sb, level + 1, "Some(%s::default().wrap(self))\n", groupName);
  }
  else
  {
  indent(sb, level, "pub fn %s(self) -> %2$s<Self> {\n",
  formatFunctionName(groupName), groupName);
 
- indent(sb, level + 1, "let acting_version = self.acting_version;\n");
- indent(sb, level + 1, "%s::default().wrap(self, acting_version as usize)\n",
- groupName);
+ indent(sb, level + 1, "%s::default().wrap(self)\n", groupName);
  }
  indent(sb, level, "}\n\n");
 
@@ -958,7 +976,8 @@ static void generateDecoderVarData(
  {
  if (varDataToken.version() > 0)
  {
- indent(sb, level + 1, "if self.acting_version < %d {\n", varDataToken.version());
+ indent(sb, level + 1, "if self.acting_version > 0 && self.acting_version < %d {\n",
+ varDataToken.version());
  indent(sb, level + 2, "return (self.parent.as_ref().unwrap().get_limit(), 0);\n");
  indent(sb, level + 1, "}\n\n");
  }
@@ -973,7 +992,8 @@ static void generateDecoderVarData(
  {
  if (varDataToken.version() > 0)
  {
- indent(sb, level + 1, "if self.acting_version < %d {\n", varDataToken.version());
+ indent(sb, level + 1, "if self.acting_version > 0 && self.acting_version < %d {\n",
+ varDataToken.version());
  indent(sb, level + 2, "return (self.get_limit(), 0);\n");
  indent(sb, level + 1, "}\n\n");
  }
@@ -992,7 +1012,8 @@ static void generateDecoderVarData(
 
  if (varDataToken.version() > 0)
  {
- indent(sb, level + 1, "if self.acting_version < %d {\n", varDataToken.version());
+ indent(sb, level + 1, "if self.acting_version > 0 && self.acting_version < %d {\n",
+ varDataToken.version());
  indent(sb, level + 2, "return &[] as &[u8];\n");
  indent(sb, level + 1, "}\n\n");
  }
@@ -1199,7 +1220,7 @@ private static void generateEnum(
  throw new IllegalArgumentException("No valid values provided for enum " + originalEnumName);
  }
 
- indent(writer, 0, "#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]\n");
+ indent(writer, 0, "#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]\n");
  final String primitiveType = rustTypeName(messageBody.get(0).encoding().primitiveType());
  indent(writer, 0, "#[repr(%s)]\n", primitiveType);
  indent(writer, 0, "pub enum %s {\n", enumRustName);
@@ -1216,16 +1237,11 @@ private static void generateEnum(
  final Encoding encoding = messageBody.get(0).encoding();
  final CharSequence nullVal = generateRustLiteral(encoding.primitiveType(),
  encoding.applicableNullValue().toString());
+ indent(writer, 1, "#[default]\n");
  indent(writer, 1, "NullVal = %s, \n", nullVal);
  }
  indent(writer, 0, "}\n");
 
- // Default implementation to support Default in other structs
- indent(writer, 0, "impl Default for %s {\n", enumRustName);
- indent(writer, 1, "#[inline]\n");
- indent(writer, 1, "fn default() -> Self { %s::%s }\n", enumRustName, "NullVal");
- indent(writer, 0, "}\n");
-
  // From impl
  indent(writer, 0, "impl From<%s> for %s {\n", primitiveType, enumRustName);
  indent(writer, 1, "#[inline]\n");
@@ -1271,8 +1287,8 @@ private static void generateComposite(
  {
  indent(out, 0, "use crate::*;\n\n");
 
- indent(out, 0, "pub use encoder::*;\n");
- indent(out, 0, "pub use decoder::*;\n\n");
+ indent(out, 0, "pub use encoder::%sEncoder;\n", formatStructName(compositeName));
+ indent(out, 0, "pub use decoder::%sDecoder;\n\n", formatStructName(compositeName));
 
  final int encodedLength = tokens.get(0).encodedLength();
  if (encodedLength > 0)

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

@@ -260,7 +260,7 @@ private static String sanitizeMethodOrProperty(final String name)
  {
  if (shadowsKeyword(name))
  {
- return name + "_";
+ return "r#" + name;
  }
  else
  {
@@ -310,7 +310,7 @@ enum ReservedKeyword
  {
  for (final ReservedKeyword value : ReservedKeyword.values())
  {
- LOWER_CASE_NAMES.add(value.name());
+ LOWER_CASE_NAMES.add(value.name().toLowerCase());
  }
  }