Add support for unnamed enumerations (#2) (2d71e489) · Commits · Public Repositories / Smithy Rust

codegen/src/main/kotlin/software/amazon/smithy/rust/codegen/smithy/generators/EnumGenerator.kt

+42 −19

Original line number	Diff line number	Diff line
		@@ -5,6 +5,7 @@

		package software.amazon.smithy.rust.codegen.smithy.generators

		import java.lang.IllegalStateException
		import software.amazon.smithy.codegen.core.SymbolProvider
		import software.amazon.smithy.model.shapes.StringShape
		import software.amazon.smithy.model.traits.EnumDefinition
		@@ -12,15 +13,20 @@ import software.amazon.smithy.model.traits.EnumTrait
		import software.amazon.smithy.rust.codegen.lang.RustWriter
		import software.amazon.smithy.rust.codegen.lang.rustBlock
		import software.amazon.smithy.rust.codegen.smithy.RuntimeType
		import software.amazon.smithy.rust.codegen.util.doubleQuote

		class EnumGenerator(
		symbolProvider: SymbolProvider,
		private val writer: RustWriter,
		shape: StringShape,
		enumTrait: EnumTrait
		private val enumTrait: EnumTrait
		) {
		companion object {
		const val Values = "values"
		}

		fun render() {
		if (enumTrait.hasNames()) {
		// pub enum Blah { V1, V2, .. }
		renderEnum()
		writer.insertTrailingNewline()
		@@ -29,16 +35,39 @@ class EnumGenerator(
		writer.insertTrailingNewline()
		// impl Blah { pub fn as_str(&self) -> &str
		renderAsStr()
		} else {
		renderUnamedEnum()
		}
		}

		private fun EnumDefinition.derivedName(): String {
		// TODO: For unnamed enums, generate a newtype that wraps the string. We can provide a &[&str] with the valid
		// values.
		private fun renderUnamedEnum() {
		writer.write("#[derive(Debug, PartialEq, Eq, Clone)]")
		writer.write("pub struct $enumName(String);")
		writer.rustBlock("impl $enumName") {
		writer.rustBlock("pub fn as_str(&self) -> &str") {
		write("&self.0")
		}

		writer.rustBlock("pub fn ${Values}() -> &'static [&'static str]") {
		withBlock("&[", "]") {
		val memberList = sortedMembers.joinToString(", ") { it.value.doubleQuote() }
		write(memberList)
		}
		}
		}

		writer.rustBlock("impl <T> \$T<T> for $enumName where T: \$T<str>", RuntimeType.From, RuntimeType.AsRef) {
		writer.rustBlock("fn from(s: T) -> Self") {
		write("$enumName(s.as_ref().to_owned())")
		}
		}
		}

		private fun EnumDefinition.derivedName(): String {
		// Because enum variants always start with an upper case letter, they will never
		// conflict with reserved words (which are always lower case), therefore, we never need
		// to fall back to raw identifiers
		return deriveName(name.orElse(null), value)
		return name.orElse(null)?.toPascalCase() ?: throw IllegalStateException("Enum variants must be named to derive a name. This is a bug.")
		}

		private val sortedMembers: List<EnumDefinition> = enumTrait.values.sortedBy { it.value }
		@@ -83,10 +112,4 @@ class EnumGenerator(
		}
		}
		}

		companion object {
		fun deriveName(name: String?, value: String): String {
		return name?.toPascalCase() ?: value.replace(" ", "_").toPascalCase().filter { it.isLetterOrDigit() }
		}
		}
		}

codegen/src/test/kotlin/software/amazon/smithy/rust/codegen/generators/EnumGeneratorTest.kt

+34 −5

Original line number	Diff line number	Diff line
		@@ -5,10 +5,10 @@

		package software.amazon.smithy.rust.codegen.generators

		import io.kotest.matchers.shouldBe
		import org.junit.jupiter.api.Test
		import software.amazon.smithy.codegen.core.SymbolProvider
		import software.amazon.smithy.model.Model
		import software.amazon.smithy.model.shapes.ShapeId
		import software.amazon.smithy.model.shapes.StringShape
		import software.amazon.smithy.model.traits.DocumentationTrait
		import software.amazon.smithy.model.traits.EnumDefinition
		@@ -16,6 +16,7 @@ import software.amazon.smithy.model.traits.EnumTrait
		import software.amazon.smithy.rust.codegen.lang.RustWriter
		import software.amazon.smithy.rust.codegen.smithy.SymbolVisitor
		import software.amazon.smithy.rust.codegen.smithy.generators.EnumGenerator
		import software.amazon.smithy.rust.testutil.asSmithy
		import software.amazon.smithy.rust.testutil.quickTest
		import software.amazon.smithy.rust.testutil.shouldCompile
		import software.amazon.smithy.rust.testutil.shouldParseAsRust
		@@ -63,9 +64,37 @@ class EnumGeneratorTest {
		}

		@Test
		fun `it derives reasonable names`() {
		EnumGenerator.deriveName(null, "Signal creation is in progress") shouldBe("SignalCreationIsInProgress")
		EnumGenerator.deriveName("as", "AS") shouldBe("As")
		EnumGenerator.deriveName(null, "Signal: creation is in progress") shouldBe("SignalCreationIsInProgress")
		fun `it generates unamed enums`() {
		val model = """
		namespace test
		@enum([
		{
		value: "Foo",
		},
		{
		value: "Baz",
		},
		{
		value: "Bar",
		},
		{
		value: "1",
		},
		{
		value: "0",
		},
		])
		string FooEnum
		""".asSmithy()
		val shape = model.expectShape(ShapeId.from("test#FooEnum"), StringShape::class.java)
		val trait = shape.expectTrait(EnumTrait::class.java)
		val provider: SymbolProvider = SymbolVisitor(model, "test")
		val writer = RustWriter("model.rs", "model")
		val generator = EnumGenerator(provider, writer, shape, trait)
		generator.render()
		writer.shouldCompile("""
		// Values should be sorted
		assert_eq!(FooEnum::${EnumGenerator.Values}(), ["0", "1", "Bar", "Baz", "Foo"]);
		""")
		}
		}