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//! Binary operator error reporting (TS2362, TS2363, TS2365, TS2469).
use crate::diagnostics::{Diagnostic, diagnostic_codes, diagnostic_messages, format_message};
use crate::state::CheckerState;
use tsz_parser::parser::NodeIndex;
use tsz_solver::TypeId;
impl<'a> CheckerState<'a> {
/// Report TS2506: Circular class inheritance (class C extends C).
pub(crate) fn error_circular_class_inheritance(
&mut self,
extends_expr_idx: NodeIndex,
class_idx: NodeIndex,
) {
// Get the class name for the error message
let class_name = if let Some(class_node) = self.ctx.arena.get(class_idx)
&& let Some(class) = self.ctx.arena.get_class(class_node)
&& class.name.is_some()
&& let Some(name_node) = self.ctx.arena.get(class.name)
{
self.ctx
.arena
.get_identifier(name_node)
.map(|id| id.escaped_text.clone())
} else {
None
};
let name = class_name.unwrap_or_else(|| String::from("<class>"));
let Some(loc) = self.get_source_location(extends_expr_idx) else {
return;
};
let message = format_message(
diagnostic_messages::IS_REFERENCED_DIRECTLY_OR_INDIRECTLY_IN_ITS_OWN_BASE_EXPRESSION,
&[&name],
);
self.ctx.error(
loc.start,
loc.length(),
message,
diagnostic_codes::IS_REFERENCED_DIRECTLY_OR_INDIRECTLY_IN_ITS_OWN_BASE_EXPRESSION,
);
}
/// Report TS2507: "Type 'X' is not a constructor function type"
/// This is for extends clauses where the base type isn't a constructor.
pub fn error_not_a_constructor_at(&mut self, type_id: TypeId, idx: NodeIndex) {
// Suppress error if type is ERROR/ANY/UNKNOWN - prevents cascading errors
if type_id == TypeId::ERROR || type_id == TypeId::ANY || type_id == TypeId::UNKNOWN {
return;
}
let Some(loc) = self.get_source_location(idx) else {
return;
};
let mut formatter = self.ctx.create_type_formatter();
let type_str = formatter.format(type_id);
let message =
diagnostic_messages::TYPE_IS_NOT_A_CONSTRUCTOR_FUNCTION_TYPE.replace("{0}", &type_str);
self.ctx.diagnostics.push(Diagnostic::error(
self.ctx.file_name.clone(),
loc.start,
loc.length(),
message,
diagnostic_codes::TYPE_IS_NOT_A_CONSTRUCTOR_FUNCTION_TYPE,
));
}
/// Report TS2351: "This expression is not constructable. Type 'X' has no construct signatures."
/// This is for `new` expressions where the expression type has no construct signatures.
pub fn error_not_constructable_at(&mut self, type_id: TypeId, idx: NodeIndex) {
if type_id == TypeId::ERROR || type_id == TypeId::ANY || type_id == TypeId::UNKNOWN {
return;
}
let Some(loc) = self.get_source_location(idx) else {
return;
};
let mut formatter = self.ctx.create_type_formatter();
let type_str = formatter.format(type_id);
let message =
diagnostic_messages::THIS_EXPRESSION_IS_NOT_CONSTRUCTABLE.replace("{0}", &type_str);
self.ctx.diagnostics.push(Diagnostic::error(
self.ctx.file_name.clone(),
loc.start,
loc.length(),
message,
diagnostic_codes::THIS_EXPRESSION_IS_NOT_CONSTRUCTABLE,
));
}
// =========================================================================
// Binary Operator Errors
// =========================================================================
/// Emits TS18050 for null/undefined operands in binary operations.
pub(crate) fn check_and_emit_nullish_binary_operands(
&mut self,
left_idx: NodeIndex,
right_idx: NodeIndex,
left_type: TypeId,
right_type: TypeId,
op: &str,
) -> bool {
if left_type == TypeId::ERROR
|| right_type == TypeId::ERROR
|| left_type == TypeId::UNKNOWN
|| right_type == TypeId::UNKNOWN
{
return false;
}
let left_is_nullish = left_type == TypeId::NULL || left_type == TypeId::UNDEFINED;
let right_is_nullish = right_type == TypeId::NULL || right_type == TypeId::UNDEFINED;
let mut emitted_nullish_error = false;
let should_emit_nullish_error = self.ctx.compiler_options.strict_null_checks
&& matches!(
op,
"+" | "-"
| "*"
| "/"
| "%"
| "**"
| "&"
| "|"
| "^"
| "<<"
| ">>"
| ">>>"
| "<"
| ">"
| "<="
| ">="
);
if left_is_nullish && should_emit_nullish_error {
let value_name = if left_type == TypeId::NULL {
"null"
} else {
"undefined"
};
if let Some(loc) = self.get_source_location(left_idx) {
let message = format_message(
diagnostic_messages::THE_VALUE_CANNOT_BE_USED_HERE,
&[value_name],
);
self.ctx.diagnostics.push(Diagnostic::error(
self.ctx.file_name.clone(),
loc.start,
loc.length(),
message,
diagnostic_codes::THE_VALUE_CANNOT_BE_USED_HERE,
));
emitted_nullish_error = true;
}
}
if right_is_nullish && should_emit_nullish_error {
let value_name = if right_type == TypeId::NULL {
"null"
} else {
"undefined"
};
if let Some(loc) = self.get_source_location(right_idx) {
let message = format_message(
diagnostic_messages::THE_VALUE_CANNOT_BE_USED_HERE,
&[value_name],
);
self.ctx.diagnostics.push(Diagnostic::error(
self.ctx.file_name.clone(),
loc.start,
loc.length(),
message,
diagnostic_codes::THE_VALUE_CANNOT_BE_USED_HERE,
));
emitted_nullish_error = true;
}
}
emitted_nullish_error
}
/// Emit errors for binary operator type mismatches.
/// TS2362 for left-hand side, TS2363 for right-hand side, or TS2365 for general operator errors.
pub(crate) fn emit_binary_operator_error(
&mut self,
node_idx: NodeIndex,
left_idx: NodeIndex,
right_idx: NodeIndex,
left_type: TypeId,
right_type: TypeId,
op: &str,
emitted_nullish_error: bool,
) {
// Suppress cascade errors from unresolved types
if left_type == TypeId::ERROR
|| right_type == TypeId::ERROR
|| left_type == TypeId::UNKNOWN
|| right_type == TypeId::UNKNOWN
{
return;
}
// Track nullish operands for proper error reporting
let left_is_nullish = left_type == TypeId::NULL || left_type == TypeId::UNDEFINED;
let right_is_nullish = right_type == TypeId::NULL || right_type == TypeId::UNDEFINED;
// TS18050 is emitted for null/undefined operands in arithmetic, bitwise, AND `+` operations.
// tsc emits TS18050 per-operand for each null/undefined value, not TS2365 for the expression.
// Relational operators (<, >, <=, >=) also emit TS18050, but only for literal null/undefined.
// For now, we only handle arithmetic/bitwise/+ since our evaluator doesn't distinguish
// literal values from variables typed as null/undefined.
// TS18050 only applies under strictNullChecks — without it, null/undefined are in
// every type's domain and should not trigger this error.
let should_emit_nullish_error = self.ctx.compiler_options.strict_null_checks
&& matches!(
op,
"+" | "-"
| "*"
| "/"
| "%"
| "**"
| "&"
| "|"
| "^"
| "<<"
| ">>"
| ">>>"
| "<"
| ">"
| "<="
| ">="
);
use tsz_solver::BinaryOpEvaluator;
let evaluator = BinaryOpEvaluator::new(self.ctx.types);
// TS2469: Check if either operand is a symbol type
// TS2469 is emitted when an operator cannot be applied to type 'symbol'
// We check both operands and emit TS2469 for the symbol operand(s)
let left_is_symbol = evaluator.is_symbol_like(left_type);
let right_is_symbol = evaluator.is_symbol_like(right_type);
if left_is_symbol || right_is_symbol {
// Format type strings first to avoid holding formatter across mutable borrows
let left_type_str =
left_is_symbol.then(|| self.ctx.create_type_formatter().format(left_type));
let right_type_str =
right_is_symbol.then(|| self.ctx.create_type_formatter().format(right_type));
// Emit TS2469 for symbol operands
if let (Some(loc), Some(type_str)) =
(self.get_source_location(left_idx), left_type_str.as_deref())
{
let message = format_message(
diagnostic_messages::OPERATOR_CANNOT_BE_APPLIED_TO_TYPE,
&[op, type_str],
);
self.ctx.diagnostics.push(Diagnostic::error(
self.ctx.file_name.clone(),
loc.start,
loc.length(),
message,
diagnostic_codes::OPERATOR_CANNOT_BE_APPLIED_TO_TYPE,
));
}
if let (Some(loc), Some(type_str)) = (
self.get_source_location(right_idx),
right_type_str.as_deref(),
) {
let message = format_message(
diagnostic_messages::OPERATOR_CANNOT_BE_APPLIED_TO_TYPE,
&[op, type_str],
);
self.ctx.diagnostics.push(Diagnostic::error(
self.ctx.file_name.clone(),
loc.start,
loc.length(),
message,
diagnostic_codes::OPERATOR_CANNOT_BE_APPLIED_TO_TYPE,
));
}
// If both are symbols, we're done (no need for TS2365)
if left_is_symbol && right_is_symbol {
return;
}
// If only one is symbol, continue to check the other operand
// (but we've already emitted TS2469 for the symbol)
}
let mut formatter = self.ctx.create_type_formatter();
let left_str = formatter.format(left_type);
let right_str = formatter.format(right_type);
// Check if this is an arithmetic or bitwise operator
// These operators require integer operands and emit TS2362/TS2363
// Note: + is handled separately - it can be string concatenation or arithmetic
let is_arithmetic = matches!(op, "-" | "*" | "/" | "%" | "**");
let is_bitwise = matches!(op, "&" | "|" | "^" | "<<" | ">>" | ">>>");
let requires_numeric_operands = is_arithmetic || is_bitwise;
// TS2447: For &, |, ^ with both boolean operands, emit special error
// This must be checked before TS2362/TS2363 because boolean is not a valid arithmetic operand
if is_bitwise {
let left_is_boolean = evaluator.is_boolean_like(left_type);
let right_is_boolean = evaluator.is_boolean_like(right_type);
let is_boolean_bitwise =
matches!(op, "&" | "|" | "^") && left_is_boolean && right_is_boolean;
if is_boolean_bitwise {
let suggestion = if op == "&" {
"&&"
} else if op == "|" {
"||"
} else {
"!=="
};
if let Some(loc) = self.get_source_location(node_idx) {
let message = format!(
"The '{op}' operator is not allowed for boolean types. Consider using '{suggestion}' instead."
);
self.ctx.diagnostics.push(Diagnostic::error(self.ctx.file_name.clone(), loc.start, loc.length(), message, diagnostic_codes::THE_OPERATOR_IS_NOT_ALLOWED_FOR_BOOLEAN_TYPES_CONSIDER_USING_INSTEAD));
}
return;
}
}
// Evaluate types to resolve unevaluated conditional/mapped types before checking.
// e.g., DeepPartial<number> | number → number
let eval_left = self.evaluate_type_for_binary_ops(left_type);
let eval_right = self.evaluate_type_for_binary_ops(right_type);
// Check if operands have valid arithmetic types using BinaryOpEvaluator
// This properly handles number, bigint, any, and enum types (unions of number literals)
// Note: evaluator was already created above for symbol checking
// Skip arithmetic checks for symbol operands (we already emitted TS2469)
// When strictNullChecks is off, null/undefined are implicitly assignable to
// number, so they should not trigger arithmetic errors.
let snc_off = !self.ctx.compiler_options.strict_null_checks;
let left_is_valid_arithmetic = !left_is_symbol
&& (evaluator.is_arithmetic_operand(eval_left)
|| (snc_off && (eval_left == TypeId::NULL || eval_left == TypeId::UNDEFINED)));
let right_is_valid_arithmetic = !right_is_symbol
&& (evaluator.is_arithmetic_operand(eval_right)
|| (snc_off && (eval_right == TypeId::NULL || eval_right == TypeId::UNDEFINED)));
// For + operator, TSC emits TS2365 ("Operator '+' cannot be applied to types"),
// never TS2362/TS2363. But if null/undefined operands already got TS18050,
// don't also emit TS2365 - tsc only emits the per-operand TS18050 errors.
if op == "+" {
if !emitted_nullish_error && let Some(loc) = self.get_source_location(node_idx) {
let message = format!(
"Operator '{op}' cannot be applied to types '{left_str}' and '{right_str}'."
);
self.ctx.diagnostics.push(Diagnostic::error(
self.ctx.file_name.clone(),
loc.start,
loc.length(),
message,
diagnostic_codes::OPERATOR_CANNOT_BE_APPLIED_TO_TYPES_AND,
));
}
return;
}
if requires_numeric_operands {
// For arithmetic and bitwise operators, emit specific left/right errors (TS2362, TS2363)
// Skip operands that already got TS18050 (null/undefined with strictNullChecks)
// tsc suppresses TS2362/TS2363 when TS18050 was already emitted for the operand.
let mut emitted_specific_error = emitted_nullish_error;
if !(left_is_valid_arithmetic || left_is_nullish && should_emit_nullish_error)
&& let Some(loc) = self.get_source_location(left_idx)
{
let message = "The left-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type.".to_string();
self.ctx.diagnostics.push(Diagnostic::error(self.ctx.file_name.clone(), loc.start, loc.length(), message, diagnostic_codes::THE_LEFT_HAND_SIDE_OF_AN_ARITHMETIC_OPERATION_MUST_BE_OF_TYPE_ANY_NUMBER_BIGINT));
emitted_specific_error = true;
}
if !(right_is_valid_arithmetic || right_is_nullish && should_emit_nullish_error)
&& let Some(loc) = self.get_source_location(right_idx)
{
let message = "The right-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type.".to_string();
self.ctx.diagnostics.push(Diagnostic::error(self.ctx.file_name.clone(), loc.start, loc.length(), message, diagnostic_codes::THE_RIGHT_HAND_SIDE_OF_AN_ARITHMETIC_OPERATION_MUST_BE_OF_TYPE_ANY_NUMBER_BIGINT));
emitted_specific_error = true;
}
// If both operands are valid arithmetic types but the operation still failed
// (e.g., mixing number and bigint), emit TS2365
if !emitted_specific_error && let Some(loc) = self.get_source_location(node_idx) {
let message = format!(
"Operator '{op}' cannot be applied to types '{left_str}' and '{right_str}'."
);
self.ctx.diagnostics.push(Diagnostic::error(
self.ctx.file_name.clone(),
loc.start,
loc.length(),
message,
diagnostic_codes::OPERATOR_CANNOT_BE_APPLIED_TO_TYPES_AND,
));
}
return;
}
// Handle relational operators: <, >, <=, >=
// These require both operands to be comparable. When types have no relationship,
// emit TS2365: "Operator '<' cannot be applied to types 'X' and 'Y'."
let is_relational = matches!(op, "<" | ">" | "<=" | ">=");
if is_relational
&& !emitted_nullish_error
&& let Some(loc) = self.get_source_location(node_idx)
{
let message = format!(
"Operator '{op}' cannot be applied to types '{left_str}' and '{right_str}'."
);
self.ctx.diagnostics.push(Diagnostic::error(
self.ctx.file_name.clone(),
loc.start,
loc.length(),
message,
diagnostic_codes::OPERATOR_CANNOT_BE_APPLIED_TO_TYPES_AND,
));
}
}
}