Improve errors displaying for container expressions

modules/main/src/main/java/com/annimon/ownlang/modules/std/std_range.java

@@ -9,9 +9,9 @@ final class std_range implements Function {
     public Value execute(Value[] args) {
         Arguments.checkRange(1, 3, args.length);
         return switch (args.length) {
-            default -> RangeValue.of(0, getLong(args[0]), 1);
             case 2 -> RangeValue.of(getLong(args[0]), getLong(args[1]), 1);
             case 3 -> RangeValue.of(getLong(args[0]), getLong(args[1]), getLong(args[2]));
+            default -> RangeValue.of(0, getLong(args[0]), 1);
         };
     }
 
@@ -41,9 +41,13 @@ final class std_range implements Function {
             this.from = from;
             this.to = to;
             this.step = step;
-            final long base = (from < to) ? (to - from) : (from - to);
+
+            final long base = (from < to)
+                    ? Math.subtractExact(to, from)
+                    : Math.subtractExact(from, to);
             final long absStep = (step < 0) ? -step : step;
-            this.size = (int) (base / absStep + (base % absStep == 0 ? 0 : 1));
+            final long longSize = (base / absStep + (base % absStep == 0 ? 0 : 1));
+            this.size = longSize > Integer.MAX_VALUE ? Integer.MAX_VALUE : (int) longSize;
         }
 
         @Override
@@ -67,9 +71,10 @@ final class std_range implements Function {
         private boolean isIntegerRange() {
             if (to > 0) {
                 return (from > Integer.MIN_VALUE && to < Integer.MAX_VALUE);
-            }
+            } else {
                 return (to > Integer.MIN_VALUE && from < Integer.MAX_VALUE);
             }
+        }
 
         @Override
         public int size() {
@@ -78,10 +83,12 @@ final class std_range implements Function {
 
         @Override
         public Value get(int index) {
+            long value = from + index * step;
             if (isIntegerRange()) {
-                return NumberValue.of((int) (from + index * step));
+                return NumberValue.of((int) (value));
+            } else {
+                return NumberValue.of(value);
             }
-            return NumberValue.of(from + (long) index * step);
         }
 
         @Override

ownlang-core/src/main/java/com/annimon/ownlang/exceptions/TypeException.java

@@ -1,8 +1,14 @@
 package com.annimon.ownlang.exceptions;
 
+import com.annimon.ownlang.util.Range;
+
 public final class TypeException extends OwnLangRuntimeException {
 
     public TypeException(String message) {
         super(message);
     }
+
+    public TypeException(String message, Range range) {
+        super(message, range);
+    }
 }

ownlang-parser/src/main/java/com/annimon/ownlang/parser/Parser.java

@@ -353,10 +353,10 @@ public final class Parser {
 
             if (lookMatch(0, TokenType.LPAREN)) {
                 // next function call
-                return functionChain(new ContainerAccessExpression(expr, indices));
+                return functionChain(new ContainerAccessExpression(expr, indices, getRange()));
             }
             // container access
-            return new ContainerAccessExpression(expr, indices);
+            return new ContainerAccessExpression(expr, indices, getRange());
         }
         return expr;
     }
@@ -532,7 +532,7 @@ public final class Parser {
         final BinaryExpression.Operator op = ASSIGN_OPERATORS.get(currentType);
         final Node expression = expression();
 
-        return new AssignmentExpression(op, (Accessible) targetExpr, expression);
+        return new AssignmentExpression(op, (Accessible) targetExpr, expression, getRange(position, index));
     }
 
     private Node ternary() {
@@ -765,9 +765,7 @@ public final class Parser {
                 args.add(expression());
                 match(TokenType.COMMA);
             }
-            final var expr = new ObjectCreationExpression(className, args);
+            return new ObjectCreationExpression(className, args, getRange(startTokenIndex, index - 1));
-            expr.setRange(getRange(startTokenIndex, index - 1));
-            return expr;
         }
         
         return unary();
@@ -859,12 +857,13 @@ public final class Parser {
         if (!match(TokenType.WORD)) return null;
 
         final List<Node> indices = variableSuffix();
-        if (indices == null || indices.isEmpty()) {
         final var variable = new VariableExpression(current.text());
         variable.setRange(getRange(startTokenIndex, index - 1));
+        if (indices == null || indices.isEmpty()) {
             return variable;
+        } else {
+            return new ContainerAccessExpression(variable, indices, variable.getRange());
         }
-        return new ContainerAccessExpression(current.text(), indices);
     }
 
     private List<Node> variableSuffix() {
@@ -905,15 +904,16 @@ public final class Parser {
                 if (lookMatch(1, TokenType.WORD) && lookMatch(2, TokenType.LPAREN)) {
                     match(TokenType.DOT);
                     return functionChain(new ContainerAccessExpression(
-                            strExpr, Collections.singletonList(
+                            strExpr,
-                                    new ValueExpression(consume(TokenType.WORD).text())
+                            Collections.singletonList(new ValueExpression(consume(TokenType.WORD).text())),
-                    )));
+                            getRange()
+                    ));
                 }
                 final List<Node> indices = variableSuffix();
                 if (indices == null || indices.isEmpty()) {
                     return strExpr;
                 }
-                return new ContainerAccessExpression(strExpr, indices);
+                return new ContainerAccessExpression(strExpr, indices, getRange());
             }
             return strExpr;
         }

ownlang-parser/src/main/java/com/annimon/ownlang/parser/ast/AssignmentExpression.java

@@ -1,22 +1,32 @@
 package com.annimon.ownlang.parser.ast;
 
+import com.annimon.ownlang.exceptions.OwnLangRuntimeException;
 import com.annimon.ownlang.lib.EvaluableValue;
 import com.annimon.ownlang.lib.Value;
+import com.annimon.ownlang.util.Range;
+import com.annimon.ownlang.util.SourceLocation;
 
 /**
  *
  * @author aNNiMON
  */
-public final class AssignmentExpression extends InterruptableNode implements Statement, EvaluableValue {
+public final class AssignmentExpression extends InterruptableNode implements Statement, EvaluableValue, SourceLocation {
 
     public final Accessible target;
     public final BinaryExpression.Operator operation;
     public final Node expression;
+    private final Range range;
     
-    public AssignmentExpression(BinaryExpression.Operator operation, Accessible target, Node expr) {
+    public AssignmentExpression(BinaryExpression.Operator operation, Accessible target, Node expr, Range range) {
         this.operation = operation;
         this.target = target;
         this.expression = expr;
+        this.range = range;
+    }
+
+    @Override
+    public Range getRange() {
+        return range;
     }
 
     @Override
@@ -24,11 +34,19 @@ public final class AssignmentExpression extends InterruptableNode implements Sta
         super.interruptionCheck();
         if (operation == null) {
             // Simple assignment
-            return target.set(expression.eval());
+            return target.set(checkNonNull(expression.eval(), "Assignment expression"));
         }
-        final Node expr1 = new ValueExpression(target.get());
+        final Node expr1 = new ValueExpression(checkNonNull(target.get(), "Assignment target"));
-        final Node expr2 = new ValueExpression(expression.eval());
+        final Node expr2 = new ValueExpression(checkNonNull(expression.eval(), "Assignment expression"));
-        return target.set(new BinaryExpression(operation, expr1, expr2).eval());
+        final Value result = new BinaryExpression(operation, expr1, expr2).eval();
+        return target.set(result);
+    }
+
+    private Value checkNonNull(Value value, String message) {
+        if (value == null) {
+            throw new OwnLangRuntimeException(message + " evaluates to null", range);
+        }
+        return value;
     }
 
     @Override

ownlang-parser/src/main/java/com/annimon/ownlang/parser/ast/ContainerAccessExpression.java

@@ -1,7 +1,10 @@
 package com.annimon.ownlang.parser.ast;
 
+import com.annimon.ownlang.exceptions.OwnLangRuntimeException;
 import com.annimon.ownlang.exceptions.TypeException;
 import com.annimon.ownlang.lib.*;
+import com.annimon.ownlang.util.Range;
+import com.annimon.ownlang.util.SourceLocation;
 import java.util.List;
 import java.util.regex.Pattern;
 
@@ -9,7 +12,7 @@ import java.util.regex.Pattern;
  *
  * @author aNNiMON
  */
-public final class ContainerAccessExpression implements Node, Accessible {
+public final class ContainerAccessExpression implements Node, Accessible, SourceLocation {
 
     private static final Pattern PATTERN_SIMPLE_INDEX = Pattern.compile("^\"[a-zA-Z$_]\\w*\"");
 
@@ -17,15 +20,13 @@ public final class ContainerAccessExpression implements Node, Accessible {
     public final List<Node> indices;
     private final boolean[] simpleIndices;
     private final boolean rootIsVariable;
+    private final Range range;
 
-    public ContainerAccessExpression(String variable, List<Node> indices) {
+    public ContainerAccessExpression(Node root, List<Node> indices, Range range) {
-        this(new VariableExpression(variable), indices);
-    }
-
-    public ContainerAccessExpression(Node root, List<Node> indices) {
         rootIsVariable = root instanceof VariableExpression;
         this.root = root;
         this.indices = indices;
+        this.range = range;
         simpleIndices = precomputeSimpleIndices();
     }
 
@@ -33,6 +34,11 @@ public final class ContainerAccessExpression implements Node, Accessible {
         return rootIsVariable;
     }
 
+    @Override
+    public Range getRange() {
+        return range;
+    }
+
     public Node getRoot() {
         return root;
     }
@@ -47,11 +53,24 @@ public final class ContainerAccessExpression implements Node, Accessible {
         final Value container = getContainer();
         final Value lastIndex = lastIndex();
         return switch (container.type()) {
-            case Types.ARRAY -> ((ArrayValue) container).get(lastIndex);
+            case Types.ARRAY -> {
+                final ArrayValue arr = (ArrayValue) container;
+                final int size = arr.size();
+                if (lastIndex.type() != Types.NUMBER) {
+                    yield arr.get(lastIndex);
+                } else {
+                    final int index = lastIndex.asInt();
+                    if (0 <= index && index < size) {
+                        yield arr.get(index);
+                    } else {
+                        throw outOfBounds(index, size);
+                    }
+                }
+            }
             case Types.MAP -> ((MapValue) container).get(lastIndex);
             case Types.STRING -> ((StringValue) container).access(lastIndex);
             case Types.CLASS -> ((ClassInstance) container).access(lastIndex);
-            default -> throw new TypeException("Array or map expected. Got " + Types.typeToString(container.type()));
+            default -> throw arrayOrMapExpected(container, " while accessing a container");
         };
     }
 
@@ -60,10 +79,19 @@ public final class ContainerAccessExpression implements Node, Accessible {
         final Value container = getContainer();
         final Value lastIndex = lastIndex();
         switch (container.type()) {
-            case Types.ARRAY -> ((ArrayValue) container).set(lastIndex.asInt(), value);
+            case Types.ARRAY -> {
+                final ArrayValue arr = (ArrayValue) container;
+                final int size = arr.size();
+                final int index = lastIndex.asInt();
+                if (0 <= index && index < size) {
+                    arr.set(index, value);
+                } else {
+                    throw outOfBounds(index, size);
+                }
+            }
             case Types.MAP -> ((MapValue) container).set(lastIndex, value);
             case Types.CLASS -> ((ClassInstance) container).set(lastIndex, value);
-            default -> throw new TypeException("Array or map expected. Got " + container.type());
+            default -> throw arrayOrMapExpected(container, " while setting a value to container");
         }
         return value;
     }
@@ -76,7 +104,7 @@ public final class ContainerAccessExpression implements Node, Accessible {
             container = switch (container.type()) {
                 case Types.ARRAY -> ((ArrayValue) container).get(index.asInt());
                 case Types.MAP -> ((MapValue) container).get(index);
-                default -> throw new TypeException("Array or map expected");
+                default -> throw arrayOrMapExpected(container, " while resolving a container");
             };
         }
         return container;
@@ -97,6 +125,17 @@ public final class ContainerAccessExpression implements Node, Accessible {
         return (MapValue) value;
     }
 
+    private OwnLangRuntimeException outOfBounds(int index, int size) {
+        return new OwnLangRuntimeException(
+                "Index %d is out of bounds for array length %d".formatted(index, size), range);
+    }
+
+    private TypeException arrayOrMapExpected(Value v, String message) {
+        return new TypeException("Array or map expected"
+                + (message == null ? "" : message)
+                + ". Got " + Types.typeToString(v.type()), range);
+    }
+    
     @Override
     public void accept(Visitor visitor) {
         visitor.visit(this);

ownlang-parser/src/main/java/com/annimon/ownlang/parser/ast/ObjectCreationExpression.java

@@ -11,14 +11,11 @@ public final class ObjectCreationExpression implements Node, SourceLocation {
     
     public final String className;
     public final List<Node> constructorArguments;
-    private Range range;
+    private final Range range;
 
-    public ObjectCreationExpression(String className, List<Node> constructorArguments) {
+    public ObjectCreationExpression(String className, List<Node> constructorArguments, Range range) {
         this.className = className;
         this.constructorArguments = constructorArguments;
-    }
-
-    public void setRange(Range range) {
         this.range = range;
     }
 

ownlang-parser/src/main/java/com/annimon/ownlang/parser/optimization/OptimizationVisitor.java

@@ -31,7 +31,7 @@ public abstract class OptimizationVisitor<T> implements ResultVisitor<Node, T> {
         final Node exprNode = s.expression.accept(this, t);
         final Node targetNode = s.target.accept(this, t);
         if ( (exprNode != s.expression || targetNode != s.target) && (targetNode instanceof Accessible) ) {
-            return new AssignmentExpression(s.operation, (Accessible) targetNode, exprNode);
+            return new AssignmentExpression(s.operation, (Accessible) targetNode, exprNode, s.getRange());
         }
         return s;
     }
@@ -79,7 +79,7 @@ public abstract class OptimizationVisitor<T> implements ResultVisitor<Node, T> {
             final AssignmentExpression newField;
             if (fieldExpr != field.expression) {
                 changed = true;
-                newField = new AssignmentExpression(field.operation, field.target, fieldExpr);
+                newField = new AssignmentExpression(field.operation, field.target, fieldExpr, field.getRange());
             } else {
                 newField = field;
             }
@@ -126,7 +126,7 @@ public abstract class OptimizationVisitor<T> implements ResultVisitor<Node, T> {
             indices.add(node);
         }
         if (changed) {
-            return new ContainerAccessExpression(root, indices);
+            return new ContainerAccessExpression(root, indices, s.getRange());
         }
         return s;
     }
@@ -356,7 +356,7 @@ public abstract class OptimizationVisitor<T> implements ResultVisitor<Node, T> {
         }
         
         if (changed) {
-            return new ObjectCreationExpression(s.className, args);
+            return new ObjectCreationExpression(s.className, args, s.getRange());
         }
         return s;
     }

ownlang-parser/src/test/java/com/annimon/ownlang/parser/ast/ASTHelper.java

@@ -44,7 +44,7 @@ public final class ASTHelper {
     }
     
     public static AssignmentExpression assign(BinaryExpression.Operator op, Accessible accessible, Node expr) {
-        return new AssignmentExpression(op, accessible, expr);
+        return new AssignmentExpression(op, accessible, expr, null);
     }
     
     public static BinaryExpression operator(BinaryExpression.Operator op, Node left, Node right) {