Fix overriding of equals, hashCode, and toString to always compile

Author: epabst

src/main/kotlin/ts2kt/TypeScriptToKotlinBase.kt

@@ -20,7 +20,27 @@ abstract class TypeScriptToKotlinBase(
 
     open fun addFunction(symbol: Symbol?, name: String, callSignature: KtCallSignature, extendsType: KtType? = null, needsNoImpl: Boolean = true, additionalAnnotations: List<KtAnnotation> = listOf(), isOverride: Boolean = false, isOperator: Boolean = false) {
         val annotations = defaultAnnotations + additionalAnnotations
-        addDeclaration(symbol, KtFunction(KtName(name), callSignature, extendsType?.let { KtHeritageType(it) }, annotations, needsNoImpl = needsNoImpl, isOverride = isOverride, hasOpenModifier = hasMembersOpenModifier, isOperator = isOperator))
+        var actualIsOverride = isOverride
+        val overrideCallSignature = if ("hashCode" == name && callSignature.params.isEmpty()) {
+            actualIsOverride = true
+            //force hashCode to return an Int so it will compile
+            callSignature.copy(returnType = callSignature.returnType.copy(type = KtType(INT)))
+        } else if ("toString" == name && callSignature.params.isEmpty()) {
+            actualIsOverride = true
+            //force toString to return a String so it will compile
+            callSignature.copy(returnType = callSignature.returnType.copy(type = KtType(STRING)))
+        } else if ("equals" == name && callSignature.params.size == 1 && callSignature.params[0].type.type.qualifiedName == ANY) {
+            actualIsOverride = true
+            callSignature.copy(
+                    //force equals to take Any? (instead of Any) so that it overrides
+                    params = callSignature.params.map { it.copy(type = it.type.copy(type = KtType(ANY, isNullable = true))) },
+                    //force equals to return a Boolean so it will compile
+                    returnType = callSignature.returnType.copy(type = KtType(BOOLEAN)))
+        } else {
+            callSignature
+        }
+        val heritageType = extendsType?.let { KtHeritageType(it) }
+        addDeclaration(symbol, KtFunction(KtName(name), overrideCallSignature, heritageType, annotations, needsNoImpl, actualIsOverride, hasMembersOpenModifier, isOperator))
     }
 
     protected fun addDeclaration(symbol: Symbol?, declaration: KtMember) {

src/main/kotlin/ts2kt/translate.kt

@@ -86,20 +86,6 @@ fun translate(srcPath: String, basePackageName: String, declareModifierIsOptiona
 //    val fileNode = languageService.getSourceFile(normalizeSrcPath)
     val fileNode = languageService.getProgram().getSourceFile(normalizeSrcPath)
 
-    inline fun isAnyMember(node: MethodDeclaration): Boolean {
-        val params = node.parameters.arr
-
-        return when (node.propertyName?.text) {
-            "equals" ->
-                params.size == 1 && params[0].type?.let { it.kind === SyntaxKind.AnyKeyword } ?: true
-            // TODO check return type ???
-            "hashCode", "toString" ->
-                params.size == 0
-            else ->
-                false
-        }
-    }
-
     /*inline*/ fun isOverrideHelper(
             node: Declaration,
             /*crossinline*/ f: (TypeChecker, Type, String) -> Boolean
@@ -172,8 +158,6 @@ fun translate(srcPath: String, basePackageName: String, declareModifierIsOptiona
     }
 
     fun isOverride(node: MethodDeclaration): Boolean {
-        if (isAnyMember(node)) return true
-
         var nodeSignature: Signature? = null
 
         return isOverrideHelper(node) { typechecker, type, nodeName ->

src/main/kotlin/ts2kt/typeScriptAstUtils.kt

@@ -25,6 +25,7 @@ import typescriptServices.ts.*
 val ANY = KtQualifiedName("Any")
 val NOTHING = KtQualifiedName("Nothing")
 val NUMBER = KtQualifiedName("Number")
+val INT = KtQualifiedName("Int")
 val STRING = KtQualifiedName("String")
 val BOOLEAN = KtQualifiedName("Boolean")
 val UNIT = KtQualifiedName("Unit")

testData/class/override/anyMembers.d.kt

@@ -1,12 +1,13 @@
 package anyMembers
 
 external open class ExpectedOverrides {
-    override fun equals(a: Any): Unit = definedExternally
-    override fun hashCode(): Number = definedExternally
+    override fun equals(a: Any?): Boolean = definedExternally
+    override fun hashCode(): Int = definedExternally
     override fun toString(): String = definedExternally
 }
 external open class ExpectedOverrides2 {
-    override fun equals(a: Any): Unit = definedExternally
+    override fun equals(a: Any?): Boolean = definedExternally
+    override fun toString(): String = definedExternally
 }
 external open class ExpectedNoOverrides {
     open fun equals(): Unit = definedExternally

testData/class/override/anyMembers.d.ts

@@ -6,6 +6,7 @@ declare class ExpectedOverrides {
 
 declare class ExpectedOverrides2 {
     equals(a);
+    toString();
 }
 
 declare class ExpectedNoOverrides {

testData/interface/override/anyMembers.d.kt

@@ -1,12 +1,12 @@
 package anyMembers
 
 external interface ExpectedOverrides {
-    override fun equals(a: Any)
-    override fun hashCode(): Number
+    override fun equals(a: Any?): Boolean
+    override fun hashCode(): Int
     override fun toString(): String
 }
 external interface ExpectedOverrides2 {
-    override fun equals(a: Any)
+    override fun equals(a: Any?): Boolean
 }
 external interface ExpectedNoOverrides {
     fun equals()