require initialization of structs and arrays at decl site

crates/analyzer/src/traversal/const_expr.rs

@@ -59,6 +59,7 @@ pub(crate) fn eval_expr(
         | ast::Expr::Attribute { .. }
         | ast::Expr::Call { .. }
         | ast::Expr::List { .. }
+        | ast::Expr::Repeat { .. }
         | ast::Expr::Tuple { .. }
         | ast::Expr::Unit => Err(not_const_error(context, expr.span)),
     }

crates/analyzer/src/traversal/declarations.rs

@@ -31,6 +31,24 @@ pub fn var_decl(scope: &mut BlockScope, stmt: &Node<fe::FuncStmt>) -> Result<(),
                     value_attributes.typ,
                 );
             }
+        } else if matches!(declared_type.typ(scope.db()), Type::Array(_)) {
+            scope.error(
+                "uninitialized variable",
+                target.span,
+                "array types must be initialized at declaration site",
+            );
+        } else if matches!(declared_type.typ(scope.db()), Type::Struct(_)) {
+            scope.error(
+                "uninitialized variable",
+                target.span,
+                "struct types must be initialized at declaration site",
+            );
+        } else if matches!(declared_type.typ(scope.db()), Type::Tuple(_)) {
+            scope.error(
+                "uninitialized variable",
+                target.span,
+                "tuple types must be initialized at declaration site",
+            );
         }
 
         add_var(scope, target, declared_type)?;

crates/analyzer/src/traversal/expressions.rs

@@ -1,21 +1,25 @@
 use crate::builtins::{ContractTypeMethod, GlobalFunction, Intrinsic, ValueMethod};
-use crate::context::{AnalyzerContext, CallType, ExpressionAttributes, Location, NamedThing};
+use crate::context::{
+    AnalyzerContext, CallType, Constant, ExpressionAttributes, Location, NamedThing,
+};
 use crate::display::Displayable;
 use crate::errors::{FatalError, IndexingError};
 use crate::namespace::items::{Class, FunctionId, Item, StructId, TypeDef};
 use crate::namespace::scopes::BlockScopeType;
 use crate::namespace::types::{Array, Base, FeString, Integer, Tuple, Type, TypeDowncast, TypeId};
 use crate::operations;
 use crate::traversal::call_args::{validate_arg_count, validate_named_args};
+use crate::traversal::const_expr::eval_expr;
 use crate::traversal::types::apply_generic_type_args;
 use crate::traversal::utils::add_bin_operations_errors;
 
 use fe_common::diagnostics::Label;
 use fe_common::{numeric, Span};
 use fe_parser::ast as fe;
-use fe_parser::ast::UnaryOperator;
+use fe_parser::ast::GenericArg;
 use fe_parser::node::Node;
 use num_bigint::BigInt;
+use num_traits::ToPrimitive;
 use smol_str::SmolStr;
 use std::ops::RangeInclusive;
 use std::rc::Rc;
@@ -45,9 +49,9 @@ pub fn expr(
             args,
         } => expr_call(context, func, generic_args, args),
         fe::Expr::List { elts } => expr_list(context, elts, expected_type),
+        fe::Expr::Repeat { .. } => expr_repeat(context, exp, expected_type),
         fe::Expr::Tuple { .. } => expr_tuple(context, exp, expected_type),
         fe::Expr::Str(_) => expr_str(context, exp, expected_type),
-
         fe::Expr::Bool(_) => Ok(ExpressionAttributes::new(
             TypeId::bool(context.db()),
             Location::Value,
@@ -134,6 +138,66 @@ pub fn expr_list(
     })
 }
 
+pub fn expr_repeat(
+    context: &mut dyn AnalyzerContext,
+    expr: &Node<fe::Expr>,
+    expected_type: Option<TypeId>,
+) -> Result<ExpressionAttributes, FatalError> {
+    let (value, len) = if let fe::Expr::Repeat { value, len } = &expr.kind {
+        (value, len)
+    } else {
+        unreachable!()
+    };
+
+    let value = assignable_expr(context, value, None)?;
+
+    let size = match &len.kind {
+        GenericArg::Int(size) => size.kind,
+        GenericArg::TypeDesc(_) => {
+            return Err(FatalError::new(context.fancy_error(
+                "expected a constant u256 value",
+                vec![Label::primary(len.span, "Array length")],
+                vec!["Note: Array length must be a constant u256".to_string()],
+            )));
+        }
+        GenericArg::ConstExpr(expr) => {
+            assignable_expr(context, expr, None)?;
+            if let Constant::Int(len) = eval_expr(context, expr)? {
+                len.to_usize().unwrap()
+            } else {
+                return Err(FatalError::new(context.fancy_error(
+                    "expected a constant u256 value",
+                    vec![Label::primary(len.span, "Array length")],
+                    vec!["Note: Array length must be a constant u256".to_string()],
+                )));
+            }
+        }
+    };
+
+    let array_typ = context.db().intern_type(Type::Array(Array {
+        size,
+        inner: value.typ,
+    }));
+
+    if let Some(expected_typ) = expected_type {
+        if expected_typ.typ(context.db()) != array_typ.typ(context.db()) {
+            return Err(FatalError::new(context.type_error(
+                "type mismatch",
+                expr.span,
+                expected_typ,
+                array_typ,
+            )));
+        }
+    }
+
+    Ok(ExpressionAttributes {
+        typ: array_typ,
+        location: Location::Memory,
+        move_location: None,
+        const_value: None,
+    })
+}
+
 /// Gather context information for expressions and check for type errors.
 ///
 /// Also ensures that the expression is on the stack.
@@ -781,7 +845,7 @@ fn expr_unary_operation(
                     Location::Value,
                 ))
             }
-            UnaryOperator::Invert => {
+            fe::UnaryOperator::Invert => {
                 if !operand_attributes.typ.is_integer(context.db()) {
                     emit_err(context, "a numeric type")
                 }

crates/analyzer/tests/errors.rs

@@ -341,3 +341,5 @@ test_file! { ctx_builtins_param_incorrect_type }
 test_file! { ctx_undefined_create }
 test_file! { ctx_undefined_create2 }
 test_file! { ctx_undefined_event }
+test_file! { uninit_values }
+test_file! { invalid_repeat_length }

crates/analyzer/tests/snapshots/analysis__aug_assign.snap

@@ -264,7 +264,7 @@ note:
    ┌─ aug_assign.fe:65:5
    │  
 65 │ ╭     pub fn add_from_mem(a: u256, b: u256) -> u256 {
-66 │ │         let my_array: Array<u256, 10>
+66 │ │         let my_array: Array<u256, 10> = [0; 10]
 67 │ │         my_array[7] = a
 68 │ │         my_array[7] += b
 69 │ │         return my_array[7]
@@ -274,12 +274,22 @@ note:
 note: 
    ┌─ aug_assign.fe:66:13
    │
-66 │         let my_array: Array<u256, 10>
+66 │         let my_array: Array<u256, 10> = [0; 10]
    │             ^^^^^^^^ Array<u256, 10>
 
 note: 
-   ┌─ aug_assign.fe:67:9
+   ┌─ aug_assign.fe:66:42
+   │
+66 │         let my_array: Array<u256, 10> = [0; 10]
+   │                                          ^  ^^ u256: Value
+   │                                          │   
+   │                                          u256: Value
+
+note: 
+   ┌─ aug_assign.fe:66:41
    │
+66 │         let my_array: Array<u256, 10> = [0; 10]
+   │                                         ^^^^^^^ Array<u256, 10>: Memory
 67 │         my_array[7] = a
    │         ^^^^^^^^ ^ u256: Value
    │         │