Last updates (#44)

* Add error message * Unnecessary hard fail * Remove useless code * Remove Base class and a test
Nissen96 · Jun 1, 2020 · c1ad73a · c1ad73a
1 parent 721d7b2
commit c1ad73a
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Showing 4 changed files with 23 additions and 25 deletions.
diff --git a/src/main/kotlin/com/egern/ast/BuildASTVisitor.kt b/src/main/kotlin/com/egern/ast/BuildASTVisitor.kt
@@ -22,7 +22,6 @@ class BuildASTVisitor : MainBaseVisitor<ASTNode>() {
 
     override fun visitClassDecl(ctx: MainParser.ClassDeclContext): ASTNode {
         val classId = ctx.CLASSNAME(0).text
-        val hasSuperclass = ctx.CLASSNAME(1) != null
         val constructor = ctx.constructor()?.let {
             it.ID().mapIndexed { index, id ->
                 Parameter(
@@ -36,7 +35,7 @@ class BuildASTVisitor : MainBaseVisitor<ASTNode>() {
         return ClassDecl(
             classId,
             constructor,
-            if (hasSuperclass) ctx.CLASSNAME(1).text else "Base",
+            ctx.CLASSNAME(1)?.text,
             if (ctx.argList() != null) ctx.argList().expr().map { it.accept(this) as Expr } else emptyList(),
             ctx.classBody().fieldDecl().map { it.accept(this) as FieldDecl },
             ctx.classBody().methodDecl().map { visitMethodDecl(it, classId) as FuncDecl },

diff --git a/src/main/kotlin/com/egern/symbols/ClassDefinition.kt b/src/main/kotlin/com/egern/symbols/ClassDefinition.kt
@@ -39,9 +39,9 @@ class ClassDefinition(
     }
 
     fun getSuperclasses(includeInterface: Boolean = true): List<String> {
-        // Insert interface before Base class
+        // Optionally insert interface
         if (includeInterface && interfaceDecl != null) {
-            return listOf(className, interfaceDecl!!.id, "Base")
+            return listOf(className, interfaceDecl!!.id)
         }
 
         return listOf(className) + (superclass?.getSuperclasses(includeInterface) ?: emptyList())

diff --git a/src/main/kotlin/com/egern/symbols/SymbolVisitor.kt b/src/main/kotlin/com/egern/symbols/SymbolVisitor.kt
@@ -8,12 +8,8 @@ class SymbolVisitor : Visitor() {
     private var currentScopeLevel = 0
     private var varCountStack = stackOf(0)
     private var fieldOffset = 0
-    private val baseClass = ClassDefinition(
-        "Base",
-        ClassDecl("Base", emptyList(), null, null, emptyList(), emptyList())
-    )
     var symbolTable = SymbolTable(0, null)
-    val classDefinitions = mutableListOf(baseClass)
+    val classDefinitions = mutableListOf<ClassDefinition>()
     val interfaces = mutableListOf<InterfaceDecl>()
 
     private fun returnToParentScope() {
@@ -24,10 +20,6 @@ class SymbolVisitor : Visitor() {
         symbolTable = SymbolTable(currentScopeLevel, symbolTable)
     }
 
-    override fun preVisit(program: Program) {
-        baseClass.symbolTable = symbolTable
-    }
-
     override fun postVisit(program: Program) {
         program.variableCount = varCountStack.pop()!!
     }
@@ -128,7 +120,7 @@ class SymbolVisitor : Visitor() {
                 )
             )
         }
-        val classDefinition = ClassDefinition(classDecl.id, classDecl, baseClass)
+        val classDefinition = ClassDefinition(classDecl.id, classDecl)
         classDefinition.symbolTable = symbolTable
         classDefinitions.add(classDefinition)
         fieldOffset = classDecl.constructor.size

diff --git a/src/main/kotlin/com/egern/types/TypeCheckingVisitor.kt b/src/main/kotlin/com/egern/types/TypeCheckingVisitor.kt
@@ -48,7 +48,7 @@ class TypeCheckingVisitor(
         }
 
         // Check if method overrides any static methods or overrides without the override modifier
-        val foundMethod = currentClass!!.superclass!!.lookupMethod(methodDecl.id)
+        val foundMethod = currentClass!!.superclass?.lookupMethod(methodDecl.id)
         if (foundMethod == null) {
             // Check if method overrides from interface
             val foundInterfaceMethod = currentClass!!.getInterface()?.methodSignatures?.find { it.id == methodDecl.id }
@@ -175,7 +175,13 @@ class TypeCheckingVisitor(
     override fun visit(classField: ClassField) {
         val callerClass = getObjectClass(classField.objectId)
         val classDefinition = classDefinitions.find { it.className == callerClass.className }
-            ?: throw Exception("Class ${callerClass.className} not defined")
+        if (classDefinition == null) {
+            ErrorLogger.log(
+                classField,
+                "Class ${callerClass.className} not defined"
+            )
+            return
+        }
 
         // Check if field exists
         val fieldDecl = classDefinition.lookupLocalField(classField.fieldId)
@@ -442,14 +448,8 @@ class TypeCheckingVisitor(
         // For each field id, check if it overrides any static field or constructor param
         fieldDecl.ids.forEach {
             // Check if any superclass contains a field of the same name
-            val superField = currentClass!!.superclass!!.lookupLocalField(it)
-            if (superField == null && fieldOverrides) {
-                // Attempt override of constructor field with local field
-                ErrorLogger.log(
-                    fieldDecl,
-                    "Constructor field $it cannot be overridden"
-                )
-            } else if (superField != null && Modifier.STATIC in superField.modifiers) {
+            val superField = currentClass!!.superclass?.lookupLocalField(it)
+            if (superField != null && Modifier.STATIC in superField.modifiers) {
                 // Attempt override of static super field
                 ErrorLogger.log(
                     fieldDecl,
@@ -462,7 +462,14 @@ class TypeCheckingVisitor(
     override fun postVisit(objectInstantiation: ObjectInstantiation) {
         // Check arguments fit the constructor parameters in number and types
         val nArgs = objectInstantiation.args.size
-        val classDefinition = classDefinitions.find { it.className == objectInstantiation.classId }!!
+        val classDefinition = classDefinitions.find { it.className == objectInstantiation.classId }
+        if (classDefinition == null) {
+            ErrorLogger.log(
+                objectInstantiation,
+                "Class ${objectInstantiation.classId} is undefined"
+            )
+            return
+        }
         val constructorFields = classDefinition.getConstructorFields()
         val nParams = constructorFields.size
         if (nArgs != nParams) {