Adds support for Sprout-generated equality/hashCode

CHANGELOG.md

@@ -45,8 +45,13 @@ Thank you to all who have contributed!
 - Adds support for Timestamp constructor call in Parser.
 - Parsing of label patterns within node and edge graph patterns now supports
   disjunction `|`, conjunction `&`, negation `!`, and grouping.
+- Adds default `equals` and `hashCode` methods for each generated abstract class of Sprout. This affects the generated
+classes in `:partiql-ast` and `:partiql-plan`.
 
 ### Changed
+- **Breaking**: all product types defined by the internal Sprout tool no longer generate interfaces. They are now abstract
+  classes due to the generation of `equals` and `hashCode` methods. This change impacts many generated interfaces exposed
+  in `:partiql-ast` and `:partiql-plan`.
 - Standardizes `org/partiql/cli/functions/QueryDDB` and other built-in functions in `org/partiql/lang/eval/builtins` by the new `ExprFunction` format.
 - **Breaking**: Redefines `org/partiql/lang/eval/ExprFunctionkt.call()` method by only invoking `callWithRequired` function.
 - **Breaking**: Redefines `org/partiql/lang/eval/builtins/DynamicLookupExprFunction` by merging `variadicParameter` into `requiredParameters` as a `StaticType.LIST`. `callWithVariadic` is now replaced by `callWithRequired`.

lib/sprout/src/main/kotlin/org/partiql/sprout/generator/target/kotlin/KotlinGenerator.kt

@@ -2,11 +2,13 @@ package org.partiql.sprout.generator.target.kotlin
 
 import com.squareup.kotlinpoet.AnnotationSpec
 import com.squareup.kotlinpoet.ClassName
+import com.squareup.kotlinpoet.CodeBlock
 import com.squareup.kotlinpoet.FunSpec
 import com.squareup.kotlinpoet.KModifier
 import com.squareup.kotlinpoet.ParameterSpec
 import com.squareup.kotlinpoet.PropertySpec
 import com.squareup.kotlinpoet.TypeSpec
+import com.squareup.kotlinpoet.asTypeName
 import net.pearx.kasechange.toCamelCase
 import org.partiql.sprout.generator.Generator
 import org.partiql.sprout.generator.target.kotlin.poems.KotlinBuilderPoem
@@ -130,7 +132,7 @@ class KotlinGenerator(private val options: KotlinOptions) : Generator<KotlinResu
                 constructor.addParameter(para)
             }
             // impls are open
-            impl.addSuperinterface(clazz)
+            impl.superclass(clazz)
             nodes.forEach { it.builder.addSuperinterface(symbols.base) }
             this.addDataClassMethods()
         }
@@ -170,14 +172,8 @@ class KotlinGenerator(private val options: KotlinOptions) : Generator<KotlinResu
     // TODO generate hashCode, equals, componentN so we can have OPEN internal implementations
     private fun KotlinNodeSpec.Product.addDataClassMethods() {
         impl.addModifiers(KModifier.INTERNAL, KModifier.OPEN)
-        // builder.addFunction(
-        //     FunSpec.builder("hashCode").addModifiers(KModifier.OVERRIDE, KModifier.ABSTRACT).returns(Int::class).build()
-        // )
-        // builder.addFunction(
-        //     FunSpec.builder("equals").addModifiers(KModifier.OVERRIDE, KModifier.ABSTRACT).returns(Boolean::class)
-        //         .addParameter(ParameterSpec.builder("other", Any::class.asTypeName().copy(nullable = true)).build())
-        //         .build()
-        // )
+        addEqualsMethod()
+        addHashCodeMethod()
         val args = listOf("_id") + props.map { it.name }
         val copy = FunSpec.builder("copy").addModifiers(KModifier.ABSTRACT).returns(clazz)
         val copyImpl = FunSpec.builder("copy")
@@ -192,4 +188,51 @@ class KotlinGenerator(private val options: KotlinOptions) : Generator<KotlinResu
         builder.addFunction(copy.build())
         impl.addFunction(copyImpl.build())
     }
+
+    /**
+     * Adds `equals` method to the core abstract class
+     */
+    private fun KotlinNodeSpec.Product.addEqualsMethod() {
+        val equalsFunctionBodyBuilder = CodeBlock.builder().let { body ->
+            body.addStatement("if (this === other) return true")
+            body.addStatement("if (other !is %T) return false", this.clazz)
+            this.props.forEach { prop ->
+                body.addStatement("if (%N != other.%N) return false", prop.name, prop.name)
+            }
+            body.addStatement("return true")
+        }
+        builder.addFunction(
+            FunSpec.builder("equals").addModifiers(KModifier.OVERRIDE).returns(Boolean::class)
+                .addParameter(ParameterSpec.builder("other", Any::class.asTypeName().copy(nullable = true)).build())
+                .addCode(equalsFunctionBodyBuilder.build())
+                .build()
+        )
+    }
+
+    /**
+     * Adds `hashCode` method to the core abstract class
+     */
+    private fun KotlinNodeSpec.Product.addHashCodeMethod() {
+        val hashcodeBodyBuilder = CodeBlock.builder().let { body ->
+            when (this.props.size) {
+                0 -> body.addStatement("return 0")
+                1 -> body.addStatement("return %N.hashCode()", this.props.first().name)
+                else -> {
+                    body.addStatement("var result = %N.hashCode()", this.props.first().name)
+                    this.props.subList(1, this.props.size).forEach { prop ->
+                        body.addStatement("result = 31 * result + %N.hashCode()", prop.name)
+                    }
+                    body.addStatement("return result")
+                }
+            }
+            body
+        }
+        builder.addFunction(
+            FunSpec.builder("hashCode")
+                .addModifiers(KModifier.OVERRIDE)
+                .returns(Int::class)
+                .addCode(hashcodeBodyBuilder.build())
+                .build()
+        )
+    }
 }

lib/sprout/src/main/kotlin/org/partiql/sprout/generator/target/kotlin/poems/KotlinBuilderPoem.kt

@@ -44,7 +44,7 @@ class KotlinBuilderPoem(symbols: KotlinSymbols) : KotlinPoem(symbols) {
     private val baseFactoryClass = ClassName(builderPackageName, baseFactoryName)
     private val baseFactory = TypeSpec.classBuilder(baseFactoryClass)
         .addSuperinterface(factoryClass)
-        .addModifiers(KModifier.ABSTRACT)
+        .addModifiers(KModifier.OPEN)
         .addProperty(
             idProvider.toBuilder()
                 .addModifiers(KModifier.OVERRIDE)
@@ -289,7 +289,7 @@ class KotlinBuilderPoem(symbols: KotlinSymbols) : KotlinPoem(symbols) {
     private fun factoryCompanion() = TypeSpec.companionObjectBuilder()
         .addProperty(
             PropertySpec.builder("DEFAULT", factoryClass)
-                .initializer("%T", factoryDefault)
+                .initializer("%T()", baseFactoryClass)
                 .build()
         )
         .addFunction(factoryFunc)

lib/sprout/src/main/kotlin/org/partiql/sprout/generator/target/kotlin/spec/KotlinNodeSpec.kt

@@ -78,7 +78,7 @@ sealed class KotlinNodeSpec(
     ) : KotlinNodeSpec(
         def = product,
         clazz = clazz,
-        builder = TypeSpec.interfaceBuilder(clazz),
+        builder = TypeSpec.classBuilder(clazz).addModifiers(KModifier.ABSTRACT),
         companion = TypeSpec.companionObjectBuilder(),
         ext = ext,
     ) {

settings.gradle.kts

@@ -27,5 +27,6 @@ include(
     "lib:sprout",
     "test:partiql-tests-runner",
     "test:partiql-randomized-tests",
+    "test:sprout-tests",
     "examples",
 )

test/sprout-tests/build.gradle.kts

@@ -0,0 +1,42 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License").
+ * You may not use this file except in compliance with the License.
+ * A copy of the License is located at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * or in the "license" file accompanying this file. This file is distributed
+ * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ * express or implied. See the License for the specific language governing
+ * permissions and limitations under the License.
+ */
+
+plugins {
+    id(Plugins.conventions)
+}
+
+dependencies {
+    api(Deps.ionElement)
+    api(project(":partiql-types"))
+}
+
+val generate = tasks.register<Exec>("generate") {
+    dependsOn(":lib:sprout:install")
+    workingDir(projectDir)
+    commandLine(
+        "../../lib/sprout/build/install/sprout/bin/sprout", "generate", "kotlin",
+        "-o", "$buildDir/generated-src",
+        "-p", "org.partiql.sprout.tests.example",
+        "-u", "Example",
+        "--poems", "visitor",
+        "--poems", "builder",
+        "--poems", "util",
+        "./src/main/resources/example.ion"
+    )
+}
+
+tasks.compileKotlin {
+    dependsOn(generate)
+}

test/sprout-tests/src/main/resources/example.ion

@@ -0,0 +1,60 @@
+imports::{
+  kotlin: [
+    ion::'com.amazon.ionelement.api.IonElement'
+  ],
+}
+
+statement::[
+
+  // PartiQL Expressions
+  query::{
+    expr: expr,
+  },
+]
+
+expr::[
+
+  // Ion Literal Value, ie `<ion>`
+  ion::{
+    value: '.ion',
+  },
+
+  // Variable Reference
+  var::{
+    identifier: identifier,
+    scope: [
+      DEFAULT,
+      //  x.y.z
+      LOCAL,
+      // @x.y.z
+    ],
+  },
+  empty::{}
+]
+// Identifiers and Qualified Identifiers
+//----------------------------------------------
+// <identifier > ::= <id symbol> | <id path>
+//
+// <id symbol> ::=  <symbol>    // case-insensitive
+//               | "<symbol>"   // case-sensitive
+//
+// <id qualified> ::= <id symbol> ('.' <id symbol>)+;
+//
+identifier::[
+  symbol::{
+    symbol: string,
+    case_sensitivity: case_sensitivity,
+  },
+  qualified::{
+    root: symbol,
+    steps: list::[
+      symbol
+    ],
+  },
+  _::[
+    case_sensitivity::[
+      SENSITIVE,
+      INSENSITIVE,
+    ],
+  ],
+]

test/sprout-tests/src/test/kotlin/org/partiql/sprout/tests/ArgumentsProviderBase.kt

@@ -0,0 +1,40 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates.  All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License").
+ * You may not use this file except in compliance with the License.
+ * A copy of the License is located at:
+ *
+ *      http://aws.amazon.com/apache2.0/
+ *
+ * or in the "license" file accompanying this file. This file is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific
+ * language governing permissions and limitations under the License.
+ */
+
+package org.partiql.sprout.tests
+
+import org.junit.jupiter.api.extension.ExtensionContext
+import org.junit.jupiter.params.provider.Arguments
+import org.junit.jupiter.params.provider.ArgumentsProvider
+import java.util.stream.Stream
+
+/**
+ * Reduces some of the boilerplate associated with the style of parameterized testing frequently
+ * utilized in this package.
+ *
+ * Since JUnit5 requires `@JvmStatic` on its `@MethodSource` argument factory methods, this requires all
+ * of the argument lists to reside in the companion object of a test class.  This can be annoying since it
+ * forces the test to be separated from its tests cases.
+ *
+ * Classes that derive from this class can be defined near the `@ParameterizedTest` functions instead.
+ */
+abstract class ArgumentsProviderBase : ArgumentsProvider {
+
+    abstract fun getParameters(): List<Any>
+
+    @Throws(Exception::class)
+    override fun provideArguments(extensionContext: ExtensionContext): Stream<out Arguments>? {
+        return getParameters().map { Arguments.of(it) }.stream()
+    }
+}