public void TwoVariableNodesWithSameNameAndTypeAreEqual()
{
var node1 = new VariableDeclarationNode(1, 2, "test", VariableType.STRING);
var node2 = new VariableDeclarationNode(71, 122, "test", VariableType.STRING);
Assert.AreEqual(node1, node2);
}
public void TwoVariableNodesWithSameNameAndTypeHaveSameHashCode()
{
var node1 = new VariableDeclarationNode(1, 2, "test", VariableType.STRING);
var node2 = new VariableDeclarationNode(71, 122, "test", VariableType.STRING);
Assert.AreEqual(node1.GetHashCode(), node2.GetHashCode());
}
public VariableData(int id, VariableDeclarationNode node)
{
this.id = id;
this.node = node;
}
public void TwoVariableNodesWithDifferentNameAndSameTypeAreNotEqual()
{
var node1 = new VariableDeclarationNode(1, 2, "test", VariableType.BOOLEAN);
var node2 = new VariableDeclarationNode(71, 122, "dfasdasd", VariableType.BOOLEAN);
Assert.AreNotEqual(node1, node2);
}
private void TypeCheckVariableAssignment(Node assignmentNode, VariableDeclarationNode declarationNode)
{
var childType = assignmentNode.Children[0].NodeType();
// if type is error type, the error has already been reported
if (declarationNode.Type != childType && childType != VariableType.ERROR_TYPE)
{
reporter.ReportError(
Error.SEMANTIC_ERROR,
"Expression has invalid type '" +
childType.Name() + "' while variable has type '" + declarationNode.Type.Name() + "'",
assignmentNode.Children[0].Line,
assignmentNode.Children[0].Column);
reporter.ReportError(
Error.NOTE,
"Variable was declared here",
declarationNode.Line,
declarationNode.Column);
}
}
private static Node HasSelfAssignment(VariableDeclarationNode node)
{
var stack = new Stack<Node>();
foreach (var child in node.Children)
{
stack.Push(child);
}
while (stack.Count != 0)
{
var current = stack.Pop();
if (current is IdentifierNode && ((IdentifierNode)current).Name == node.Name)
{
return current;
}
foreach (var child in current.Children)
{
stack.Push(child);
}
}
return null;
}
public void Visit(VariableDeclarationNode node)
{
if (SymbolTable.ContainsKey(node.Name))
{
reporter.ReportError(
Error.SEMANTIC_ERROR,
"Redeclaration of variable '" + node.Name + "'",
node.Line,
node.Column);
var name = node.Name;
NoteVariableWasDeclaredHere(name);
}
else
{
SymbolTable[node.Name] = new VariableData(variableId++, node);
}
if (node.Children.Count == 0)
{
return;
}
if (node.Children.Count > 1)
{
throw new InternalCompilerError("Variable declaration node has more children than 1");
}
node.Children[0].Accept(this);
TypeCheckVariableAssignment(node, node);
Node n = null;
if ((n = HasSelfAssignment(node)) != null)
{
reporter.ReportError(
Error.SEMANTIC_ERROR,
"Cannot initialize variable with self",
n.Line,
n.Column);
}
}
public void Visit(VariableDeclarationNode node)
{
if (node.Children.Count == 0)
{
// default initialize
if (node.Type == VariableType.INTEGER)
{
Emit(Bytecode.PUSH_INT);
Emit(0L);
}
else if (node.Type == VariableType.STRING)
{
Emit(Bytecode.PUSH_STRING);
Emit(0);
}
else if (node.Type == VariableType.BOOLEAN)
{
Emit(Bytecode.PUSH_FALSE);
}
else
{
throw new InternalCompilerError("Invalid variable type for variable declaration");
}
}
else
{
node.Children[0].Accept(this);
}
Emit(Bytecode.STORE_VARIABLE);
Emit(symbolTable[node.Name].id);
}