Code structure cleanup.
This commit is contained in:
Stephen Chung
294
src/parse_error.rs
Normal file
294
src/parse_error.rs
Normal file
@@ -0,0 +1,294 @@
|
||||
//! Module containing error definitions for the parsing process.
|
||||
|
||||
use crate::result::EvalAltResult;
|
||||
use crate::token::Position;
|
||||
|
||||
use crate::stdlib::{
|
||||
boxed::Box,
|
||||
error::Error,
|
||||
fmt,
|
||||
string::{String, ToString},
|
||||
};
|
||||
|
||||
/// _[INTERNALS]_ Error encountered when tokenizing the script text.
|
||||
/// Exported under the `internals` feature only.
|
||||
///
|
||||
/// ## WARNING
|
||||
///
|
||||
/// This type is volatile and may change.
|
||||
#[derive(Debug, Eq, PartialEq, Clone, Hash)]
|
||||
#[non_exhaustive]
|
||||
pub enum LexError {
|
||||
/// An unexpected symbol is encountered when tokenizing the script text.
|
||||
UnexpectedInput(String),
|
||||
/// A string literal is not terminated before a new-line or EOF.
|
||||
UnterminatedString,
|
||||
/// An identifier is in an invalid format.
|
||||
StringTooLong(usize),
|
||||
/// An string/character/numeric escape sequence is in an invalid format.
|
||||
MalformedEscapeSequence(String),
|
||||
/// An numeric literal is in an invalid format.
|
||||
MalformedNumber(String),
|
||||
/// An character literal is in an invalid format.
|
||||
MalformedChar(String),
|
||||
/// An identifier is in an invalid format.
|
||||
MalformedIdentifier(String),
|
||||
/// Bad symbol encountered when tokenizing the script text.
|
||||
ImproperSymbol(String),
|
||||
}
|
||||
|
||||
impl Error for LexError {}
|
||||
|
||||
impl fmt::Display for LexError {
|
||||
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
|
||||
match self {
|
||||
Self::UnexpectedInput(s) => write!(f, "Unexpected '{}'", s),
|
||||
Self::MalformedEscapeSequence(s) => write!(f, "Invalid escape sequence: '{}'", s),
|
||||
Self::MalformedNumber(s) => write!(f, "Invalid number: '{}'", s),
|
||||
Self::MalformedChar(s) => write!(f, "Invalid character: '{}'", s),
|
||||
Self::MalformedIdentifier(s) => write!(f, "Variable name is not proper: '{}'", s),
|
||||
Self::UnterminatedString => write!(f, "Open string is not terminated"),
|
||||
Self::StringTooLong(max) => write!(
|
||||
f,
|
||||
"Length of string literal exceeds the maximum limit ({})",
|
||||
max
|
||||
),
|
||||
Self::ImproperSymbol(s) => f.write_str(s),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl LexError {
|
||||
/// Convert a `LexError` into a `ParseError`.
|
||||
#[inline(always)]
|
||||
pub fn into_err(&self, pos: Position) -> ParseError {
|
||||
ParseError(Box::new(self.into()), pos)
|
||||
}
|
||||
}
|
||||
|
||||
/// Type of error encountered when parsing a script.
|
||||
///
|
||||
/// Some errors never appear when certain features are turned on.
|
||||
/// They still exist so that the application can turn features on and off without going through
|
||||
/// massive code changes to remove/add back enum variants in match statements.
|
||||
#[derive(Debug, Eq, PartialEq, Clone, Hash)]
|
||||
#[non_exhaustive]
|
||||
pub enum ParseErrorType {
|
||||
/// Error in the script text. Wrapped value is the error message.
|
||||
BadInput(String),
|
||||
/// The script ends prematurely.
|
||||
UnexpectedEOF,
|
||||
/// An unknown operator is encountered. Wrapped value is the operator.
|
||||
UnknownOperator(String),
|
||||
/// Expecting a particular token but not finding one. Wrapped values are the token and description.
|
||||
MissingToken(String, String),
|
||||
/// An expression in function call arguments `()` has syntax error. Wrapped value is the error description (if any).
|
||||
MalformedCallExpr(String),
|
||||
/// An expression in indexing brackets `[]` has syntax error. Wrapped value is the error description (if any).
|
||||
///
|
||||
/// Never appears under the `no_index` feature.
|
||||
MalformedIndexExpr(String),
|
||||
/// An expression in an `in` expression has syntax error. Wrapped value is the error description (if any).
|
||||
///
|
||||
/// Never appears under the `no_object` and `no_index` features combination.
|
||||
MalformedInExpr(String),
|
||||
/// A capturing has syntax error. Wrapped value is the error description (if any).
|
||||
///
|
||||
/// Never appears under the `no_closure` feature.
|
||||
MalformedCapture(String),
|
||||
/// A map definition has duplicated property names. Wrapped value is the property name.
|
||||
///
|
||||
/// Never appears under the `no_object` feature.
|
||||
DuplicatedProperty(String),
|
||||
/// Missing a property name for custom types and maps.
|
||||
///
|
||||
/// Never appears under the `no_object` feature.
|
||||
PropertyExpected,
|
||||
/// Missing a variable name after the `let`, `const`, `for` or `catch` keywords.
|
||||
VariableExpected,
|
||||
/// An identifier is a reserved keyword.
|
||||
Reserved(String),
|
||||
/// Missing an expression. Wrapped value is the expression type.
|
||||
ExprExpected(String),
|
||||
/// Defining a function `fn` in an appropriate place (e.g. inside another function).
|
||||
///
|
||||
/// Never appears under the `no_function` feature.
|
||||
WrongFnDefinition,
|
||||
/// Missing a function name after the `fn` keyword.
|
||||
///
|
||||
/// Never appears under the `no_function` feature.
|
||||
FnMissingName,
|
||||
/// A function definition is missing the parameters list. Wrapped value is the function name.
|
||||
///
|
||||
/// Never appears under the `no_function` feature.
|
||||
FnMissingParams(String),
|
||||
/// A function definition has duplicated parameters. Wrapped values are the function name and parameter name.
|
||||
///
|
||||
/// Never appears under the `no_function` feature.
|
||||
FnDuplicatedParam(String, String),
|
||||
/// A function definition is missing the body. Wrapped value is the function name.
|
||||
///
|
||||
/// Never appears under the `no_function` feature.
|
||||
FnMissingBody(String),
|
||||
/// An export statement has duplicated names.
|
||||
///
|
||||
/// Never appears under the `no_module` feature.
|
||||
DuplicatedExport(String),
|
||||
/// Export statement not at global level.
|
||||
///
|
||||
/// Never appears under the `no_module` feature.
|
||||
WrongExport,
|
||||
/// Assignment to an a constant variable. Wrapped value is the constant variable name.
|
||||
AssignmentToConstant(String),
|
||||
/// Assignment to an inappropriate LHS (left-hand-side) expression.
|
||||
/// Wrapped value is the error message (if any).
|
||||
AssignmentToInvalidLHS(String),
|
||||
/// Expression exceeding the maximum levels of complexity.
|
||||
///
|
||||
/// Never appears under the `unchecked` feature.
|
||||
ExprTooDeep,
|
||||
/// Literal exceeding the maximum size. Wrapped values are the data type name and the maximum size.
|
||||
///
|
||||
/// Never appears under the `unchecked` feature.
|
||||
LiteralTooLarge(String, usize),
|
||||
/// Break statement not inside a loop.
|
||||
LoopBreak,
|
||||
}
|
||||
|
||||
impl ParseErrorType {
|
||||
/// Make a `ParseError` using the current type and position.
|
||||
#[inline(always)]
|
||||
pub(crate) fn into_err(self, pos: Position) -> ParseError {
|
||||
ParseError(Box::new(self), pos)
|
||||
}
|
||||
|
||||
pub(crate) fn desc(&self) -> &str {
|
||||
match self {
|
||||
Self::BadInput(p) => p,
|
||||
Self::UnexpectedEOF => "Script is incomplete",
|
||||
Self::UnknownOperator(_) => "Unknown operator",
|
||||
Self::MissingToken(_, _) => "Expecting a certain token that is missing",
|
||||
Self::MalformedCallExpr(_) => "Invalid expression in function call arguments",
|
||||
Self::MalformedIndexExpr(_) => "Invalid index in indexing expression",
|
||||
Self::MalformedInExpr(_) => "Invalid 'in' expression",
|
||||
Self::MalformedCapture(_) => "Invalid capturing",
|
||||
Self::DuplicatedProperty(_) => "Duplicated property in object map literal",
|
||||
Self::PropertyExpected => "Expecting name of a property",
|
||||
Self::VariableExpected => "Expecting name of a variable",
|
||||
Self::Reserved(_) => "Invalid use of reserved keyword",
|
||||
Self::ExprExpected(_) => "Expecting an expression",
|
||||
Self::FnMissingName => "Expecting function name in function declaration",
|
||||
Self::FnMissingParams(_) => "Expecting parameters in function declaration",
|
||||
Self::FnDuplicatedParam(_,_) => "Duplicated parameters in function declaration",
|
||||
Self::FnMissingBody(_) => "Expecting body statement block for function declaration",
|
||||
Self::WrongFnDefinition => "Function definitions must be at global level and cannot be inside a block or another function",
|
||||
Self::DuplicatedExport(_) => "Duplicated variable/function in export statement",
|
||||
Self::WrongExport => "Export statement can only appear at global level",
|
||||
Self::AssignmentToConstant(_) => "Cannot assign to a constant value",
|
||||
Self::AssignmentToInvalidLHS(_) => "Expression cannot be assigned to",
|
||||
Self::ExprTooDeep => "Expression exceeds maximum complexity",
|
||||
Self::LiteralTooLarge(_, _) => "Literal exceeds maximum limit",
|
||||
Self::LoopBreak => "Break statement should only be used inside a loop"
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl fmt::Display for ParseErrorType {
|
||||
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
|
||||
match self {
|
||||
Self::BadInput(s) | ParseErrorType::MalformedCallExpr(s) => {
|
||||
f.write_str(if s.is_empty() { self.desc() } else { s })
|
||||
}
|
||||
Self::UnknownOperator(s) => write!(f, "{}: '{}'", self.desc(), s),
|
||||
|
||||
Self::MalformedIndexExpr(s) | Self::MalformedInExpr(s) | Self::MalformedCapture(s) => {
|
||||
f.write_str(if s.is_empty() { self.desc() } else { s })
|
||||
}
|
||||
|
||||
Self::DuplicatedProperty(s) => {
|
||||
write!(f, "Duplicated property '{}' for object map literal", s)
|
||||
}
|
||||
|
||||
Self::ExprExpected(s) => write!(f, "Expecting {} expression", s),
|
||||
|
||||
Self::FnMissingParams(s) => write!(f, "Expecting parameters for function '{}'", s),
|
||||
|
||||
Self::FnMissingBody(s) if s.is_empty() => {
|
||||
f.write_str("Expecting body statement block for anonymous function")
|
||||
}
|
||||
Self::FnMissingBody(s) => {
|
||||
write!(f, "Expecting body statement block for function '{}'", s)
|
||||
}
|
||||
|
||||
Self::FnDuplicatedParam(s, arg) => {
|
||||
write!(f, "Duplicated parameter '{}' for function '{}'", arg, s)
|
||||
}
|
||||
|
||||
Self::DuplicatedExport(s) => write!(
|
||||
f,
|
||||
"Duplicated variable/function '{}' in export statement",
|
||||
s
|
||||
),
|
||||
|
||||
Self::MissingToken(token, s) => write!(f, "Expecting '{}' {}", token, s),
|
||||
|
||||
Self::AssignmentToConstant(s) if s.is_empty() => f.write_str(self.desc()),
|
||||
Self::AssignmentToConstant(s) => write!(f, "Cannot assign to constant '{}'", s),
|
||||
|
||||
Self::AssignmentToInvalidLHS(s) if s.is_empty() => f.write_str(self.desc()),
|
||||
Self::AssignmentToInvalidLHS(s) => f.write_str(s),
|
||||
|
||||
Self::LiteralTooLarge(typ, max) => {
|
||||
write!(f, "{} exceeds the maximum limit ({})", typ, max)
|
||||
}
|
||||
Self::Reserved(s) => write!(f, "'{}' is a reserved keyword", s),
|
||||
_ => f.write_str(self.desc()),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl From<&LexError> for ParseErrorType {
|
||||
#[inline(always)]
|
||||
fn from(err: &LexError) -> Self {
|
||||
match err {
|
||||
LexError::StringTooLong(max) => {
|
||||
Self::LiteralTooLarge("Length of string literal".to_string(), *max)
|
||||
}
|
||||
_ => Self::BadInput(err.to_string()),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// Error when parsing a script.
|
||||
#[derive(Debug, Eq, PartialEq, Clone, Hash)]
|
||||
pub struct ParseError(pub Box<ParseErrorType>, pub Position);
|
||||
|
||||
impl Error for ParseError {}
|
||||
|
||||
impl fmt::Display for ParseError {
|
||||
#[inline]
|
||||
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
|
||||
fmt::Display::fmt(&self.0, f)?;
|
||||
|
||||
// Do not write any position if None
|
||||
if !self.1.is_none() {
|
||||
write!(f, " ({})", self.1)?;
|
||||
}
|
||||
|
||||
Ok(())
|
||||
}
|
||||
}
|
||||
|
||||
impl From<ParseErrorType> for Box<EvalAltResult> {
|
||||
#[inline(always)]
|
||||
fn from(err: ParseErrorType) -> Self {
|
||||
Box::new(EvalAltResult::ErrorParsing(err, Position::none()))
|
||||
}
|
||||
}
|
||||
|
||||
impl From<ParseError> for Box<EvalAltResult> {
|
||||
#[inline(always)]
|
||||
fn from(err: ParseError) -> Self {
|
||||
Box::new(EvalAltResult::ErrorParsing(*err.0, err.1))
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user