| // pest. The Elegant Parser |
| // Copyright (c) 2018 DragoČ™ Tiselice |
| // |
| // Licensed under the Apache License, Version 2.0 |
| // <LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0> or the MIT |
| // license <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. All files in the project carrying such notice may not be copied, |
| // modified, or distributed except according to those terms. |
| |
| //! Helpers for validating pest grammars that could help with debugging |
| //! and provide a more user-friendly error message. |
| |
| use once_cell::sync::Lazy; |
| use std::collections::{HashMap, HashSet}; |
| |
| use pest::error::{Error, ErrorVariant, InputLocation}; |
| use pest::iterators::Pairs; |
| use pest::unicode::unicode_property_names; |
| use pest::Span; |
| |
| use crate::parser::{ParserExpr, ParserNode, ParserRule, Rule}; |
| |
| static RUST_KEYWORDS: Lazy<HashSet<&'static str>> = Lazy::new(|| { |
| [ |
| "abstract", "alignof", "as", "become", "box", "break", "const", "continue", "crate", "do", |
| "else", "enum", "extern", "false", "final", "fn", "for", "if", "impl", "in", "let", "loop", |
| "macro", "match", "mod", "move", "mut", "offsetof", "override", "priv", "proc", "pure", |
| "pub", "ref", "return", "Self", "self", "sizeof", "static", "struct", "super", "trait", |
| "true", "type", "typeof", "unsafe", "unsized", "use", "virtual", "where", "while", "yield", |
| ] |
| .iter() |
| .cloned() |
| .collect() |
| }); |
| |
| static PEST_KEYWORDS: Lazy<HashSet<&'static str>> = Lazy::new(|| { |
| [ |
| "_", "ANY", "DROP", "EOI", "PEEK", "PEEK_ALL", "POP", "POP_ALL", "PUSH", "SOI", |
| ] |
| .iter() |
| .cloned() |
| .collect() |
| }); |
| |
| static BUILTINS: Lazy<HashSet<&'static str>> = Lazy::new(|| { |
| [ |
| "ANY", |
| "DROP", |
| "EOI", |
| "PEEK", |
| "PEEK_ALL", |
| "POP", |
| "POP_ALL", |
| "SOI", |
| "ASCII_DIGIT", |
| "ASCII_NONZERO_DIGIT", |
| "ASCII_BIN_DIGIT", |
| "ASCII_OCT_DIGIT", |
| "ASCII_HEX_DIGIT", |
| "ASCII_ALPHA_LOWER", |
| "ASCII_ALPHA_UPPER", |
| "ASCII_ALPHA", |
| "ASCII_ALPHANUMERIC", |
| "ASCII", |
| "NEWLINE", |
| ] |
| .iter() |
| .cloned() |
| .chain(unicode_property_names()) |
| .collect::<HashSet<&str>>() |
| }); |
| |
| /// It checks the parsed grammar for common mistakes: |
| /// - using Pest keywords |
| /// - duplicate rules |
| /// - undefined rules |
| /// |
| /// It returns a `Result` with a `Vec` of `Error`s if any of the above is found. |
| /// If no errors are found, it returns the vector of names of used builtin rules. |
| pub fn validate_pairs(pairs: Pairs<'_, Rule>) -> Result<Vec<&str>, Vec<Error<Rule>>> { |
| let definitions: Vec<_> = pairs |
| .clone() |
| .filter(|pair| pair.as_rule() == Rule::grammar_rule) |
| .map(|pair| pair.into_inner().next().unwrap()) |
| .filter(|pair| pair.as_rule() != Rule::line_doc) |
| .map(|pair| pair.as_span()) |
| .collect(); |
| |
| let called_rules: Vec<_> = pairs |
| .clone() |
| .filter(|pair| pair.as_rule() == Rule::grammar_rule) |
| .flat_map(|pair| { |
| pair.into_inner() |
| .flatten() |
| .skip(1) |
| .filter(|pair| pair.as_rule() == Rule::identifier) |
| .map(|pair| pair.as_span()) |
| }) |
| .collect(); |
| |
| let mut errors = vec![]; |
| |
| errors.extend(validate_pest_keywords(&definitions)); |
| errors.extend(validate_already_defined(&definitions)); |
| errors.extend(validate_undefined(&definitions, &called_rules)); |
| |
| if !errors.is_empty() { |
| return Err(errors); |
| } |
| |
| let definitions: HashSet<_> = definitions.iter().map(|span| span.as_str()).collect(); |
| let called_rules: HashSet<_> = called_rules.iter().map(|span| span.as_str()).collect(); |
| |
| let defaults = called_rules.difference(&definitions); |
| |
| Ok(defaults.cloned().collect()) |
| } |
| |
| /// Validates that the given `definitions` do not contain any Rust keywords. |
| #[allow(clippy::ptr_arg)] |
| #[deprecated = "Rust keywords are no longer restricted from the pest grammar"] |
| pub fn validate_rust_keywords(definitions: &Vec<Span<'_>>) -> Vec<Error<Rule>> { |
| let mut errors = vec![]; |
| |
| for definition in definitions { |
| let name = definition.as_str(); |
| |
| if RUST_KEYWORDS.contains(name) { |
| errors.push(Error::new_from_span( |
| ErrorVariant::CustomError { |
| message: format!("{} is a rust keyword", name), |
| }, |
| *definition, |
| )) |
| } |
| } |
| |
| errors |
| } |
| |
| /// Validates that the given `definitions` do not contain any Pest keywords. |
| #[allow(clippy::ptr_arg)] |
| pub fn validate_pest_keywords(definitions: &Vec<Span<'_>>) -> Vec<Error<Rule>> { |
| let mut errors = vec![]; |
| |
| for definition in definitions { |
| let name = definition.as_str(); |
| |
| if PEST_KEYWORDS.contains(name) { |
| errors.push(Error::new_from_span( |
| ErrorVariant::CustomError { |
| message: format!("{} is a pest keyword", name), |
| }, |
| *definition, |
| )) |
| } |
| } |
| |
| errors |
| } |
| |
| /// Validates that the given `definitions` do not contain any duplicate rules. |
| #[allow(clippy::ptr_arg)] |
| pub fn validate_already_defined(definitions: &Vec<Span<'_>>) -> Vec<Error<Rule>> { |
| let mut errors = vec![]; |
| let mut defined = HashSet::new(); |
| |
| for definition in definitions { |
| let name = definition.as_str(); |
| |
| if defined.contains(&name) { |
| errors.push(Error::new_from_span( |
| ErrorVariant::CustomError { |
| message: format!("rule {} already defined", name), |
| }, |
| *definition, |
| )) |
| } else { |
| defined.insert(name); |
| } |
| } |
| |
| errors |
| } |
| |
| /// Validates that the given `definitions` do not contain any undefined rules. |
| #[allow(clippy::ptr_arg)] |
| pub fn validate_undefined<'i>( |
| definitions: &Vec<Span<'i>>, |
| called_rules: &Vec<Span<'i>>, |
| ) -> Vec<Error<Rule>> { |
| let mut errors = vec![]; |
| let definitions: HashSet<_> = definitions.iter().map(|span| span.as_str()).collect(); |
| |
| for rule in called_rules { |
| let name = rule.as_str(); |
| |
| if !definitions.contains(name) && !BUILTINS.contains(name) { |
| errors.push(Error::new_from_span( |
| ErrorVariant::CustomError { |
| message: format!("rule {} is undefined", name), |
| }, |
| *rule, |
| )) |
| } |
| } |
| |
| errors |
| } |
| |
| /// Validates the abstract syntax tree for common mistakes: |
| /// - infinite repetitions |
| /// - choices that cannot be reached |
| /// - left recursion |
| #[allow(clippy::ptr_arg)] |
| pub fn validate_ast<'a, 'i: 'a>(rules: &'a Vec<ParserRule<'i>>) -> Vec<Error<Rule>> { |
| let mut errors = vec![]; |
| |
| // WARNING: validate_{repetition,choice,whitespace_comment} |
| // use is_non_failing and is_non_progressing breaking assumptions: |
| // - for every `ParserExpr::RepMinMax(inner,min,max)`, |
| // `min<=max` was not checked |
| // - left recursion was not checked |
| // - Every expression might not be checked |
| errors.extend(validate_repetition(rules)); |
| errors.extend(validate_choices(rules)); |
| errors.extend(validate_whitespace_comment(rules)); |
| errors.extend(validate_left_recursion(rules)); |
| |
| errors.sort_by_key(|error| match error.location { |
| InputLocation::Span(span) => span, |
| _ => unreachable!(), |
| }); |
| |
| errors |
| } |
| |
| /// Checks if `expr` is non-progressing, that is the expression does not |
| /// consume any input or any stack. This includes expressions matching the empty input, |
| /// `SOI` and ̀ `EOI`, predicates and repetitions. |
| /// |
| /// # Example |
| /// |
| /// ```pest |
| /// not_progressing_1 = { "" } |
| /// not_progressing_2 = { "a"? } |
| /// not_progressing_3 = { !"a" } |
| /// ``` |
| /// |
| /// # Assumptions |
| /// - In `ParserExpr::RepMinMax(inner,min,max)`, `min<=max` |
| /// - All rules identiers have a matching definition |
| /// - There is no left-recursion (if only this one is broken returns false) |
| /// - Every expression is being checked |
| fn is_non_progressing<'i>( |
| expr: &ParserExpr<'i>, |
| rules: &HashMap<String, &ParserNode<'i>>, |
| trace: &mut Vec<String>, |
| ) -> bool { |
| match *expr { |
| ParserExpr::Str(ref string) | ParserExpr::Insens(ref string) => string.is_empty(), |
| ParserExpr::Ident(ref ident) => { |
| if ident == "SOI" || ident == "EOI" { |
| return true; |
| } |
| |
| if !trace.contains(ident) { |
| if let Some(node) = rules.get(ident) { |
| trace.push(ident.clone()); |
| let result = is_non_progressing(&node.expr, rules, trace); |
| trace.pop().unwrap(); |
| |
| return result; |
| } |
| // else |
| // the ident is |
| // - "POP","PEEK" => false |
| // the slice being checked is not non_progressing since every |
| // PUSH is being checked (assumption 4) and the expr |
| // of a PUSH has to be non_progressing. |
| // - "POPALL", "PEEKALL" => false |
| // same as "POP", "PEEK" unless the following: |
| // BUG: if the stack is empty they are non_progressing |
| // - "DROP" => false doesn't consume the input but consumes the stack, |
| // - "ANY", "ASCII_*", UNICODE categories, "NEWLINE" => false |
| // - referring to another rule that is undefined (breaks assumption) |
| } |
| // else referring to another rule that was already seen. |
| // this happens only if there is a left-recursion |
| // that is only if an assumption is broken, |
| // WARNING: we can choose to return false, but that might |
| // cause bugs into the left_recursion check |
| |
| false |
| } |
| ParserExpr::Seq(ref lhs, ref rhs) => { |
| is_non_progressing(&lhs.expr, rules, trace) |
| && is_non_progressing(&rhs.expr, rules, trace) |
| } |
| ParserExpr::Choice(ref lhs, ref rhs) => { |
| is_non_progressing(&lhs.expr, rules, trace) |
| || is_non_progressing(&rhs.expr, rules, trace) |
| } |
| // WARNING: the predicate indeed won't make progress on input but it |
| // might progress on the stack |
| // ex: @{ PUSH(ANY) ~ (&(DROP))* ~ ANY }, input="AA" |
| // Notice that this is ex not working as of now, the debugger seems |
| // to run into an infinite loop on it |
| ParserExpr::PosPred(_) | ParserExpr::NegPred(_) => true, |
| ParserExpr::Rep(_) | ParserExpr::Opt(_) | ParserExpr::RepMax(_, _) => true, |
| // it either always fail (failing is progressing) |
| // or always match at least a character |
| ParserExpr::Range(_, _) => false, |
| ParserExpr::PeekSlice(_, _) => { |
| // the slice being checked is not non_progressing since every |
| // PUSH is being checked (assumption 4) and the expr |
| // of a PUSH has to be non_progressing. |
| // BUG: if the slice is of size 0, or the stack is not large |
| // enough it might be non-progressing |
| false |
| } |
| |
| ParserExpr::RepExact(ref inner, min) |
| | ParserExpr::RepMin(ref inner, min) |
| | ParserExpr::RepMinMax(ref inner, min, _) => { |
| min == 0 || is_non_progressing(&inner.expr, rules, trace) |
| } |
| ParserExpr::Push(ref inner) => is_non_progressing(&inner.expr, rules, trace), |
| ParserExpr::RepOnce(ref inner) => is_non_progressing(&inner.expr, rules, trace), |
| #[cfg(feature = "grammar-extras")] |
| ParserExpr::NodeTag(ref inner, _) => is_non_progressing(&inner.expr, rules, trace), |
| } |
| } |
| |
| /// Checks if `expr` is non-failing, that is it matches any input. |
| /// |
| /// # Example |
| /// |
| /// ```pest |
| /// non_failing_1 = { "" } |
| /// ``` |
| /// |
| /// # Assumptions |
| /// - In `ParserExpr::RepMinMax(inner,min,max)`, `min<=max` |
| /// - In `ParserExpr::PeekSlice(max,Some(min))`, `max>=min` |
| /// - All rules identiers have a matching definition |
| /// - There is no left-recursion |
| /// - All rules are being checked |
| fn is_non_failing<'i>( |
| expr: &ParserExpr<'i>, |
| rules: &HashMap<String, &ParserNode<'i>>, |
| trace: &mut Vec<String>, |
| ) -> bool { |
| match *expr { |
| ParserExpr::Str(ref string) | ParserExpr::Insens(ref string) => string.is_empty(), |
| ParserExpr::Ident(ref ident) => { |
| if !trace.contains(ident) { |
| if let Some(node) = rules.get(ident) { |
| trace.push(ident.clone()); |
| let result = is_non_failing(&node.expr, rules, trace); |
| trace.pop().unwrap(); |
| |
| result |
| } else { |
| // else |
| // the ident is |
| // - "POP","PEEK" => false |
| // the slice being checked is not non_failing since every |
| // PUSH is being checked (assumption 4) and the expr |
| // of a PUSH has to be non_failing. |
| // - "POP_ALL", "PEEK_ALL" => false |
| // same as "POP", "PEEK" unless the following: |
| // BUG: if the stack is empty they are non_failing |
| // - "DROP" => false |
| // - "ANY", "ASCII_*", UNICODE categories, "NEWLINE", |
| // "SOI", "EOI" => false |
| // - referring to another rule that is undefined (breaks assumption) |
| // WARNING: might want to introduce a panic or report the error |
| false |
| } |
| } else { |
| // referring to another rule R that was already seen |
| // WARNING: this might mean there is a circular non-failing path |
| // it's not obvious wether this can happen without left-recursion |
| // and thus breaking the assumption. Until there is answer to |
| // this, to avoid changing behaviour we return: |
| false |
| } |
| } |
| ParserExpr::Opt(_) => true, |
| ParserExpr::Rep(_) => true, |
| ParserExpr::RepMax(_, _) => true, |
| ParserExpr::Seq(ref lhs, ref rhs) => { |
| is_non_failing(&lhs.expr, rules, trace) && is_non_failing(&rhs.expr, rules, trace) |
| } |
| ParserExpr::Choice(ref lhs, ref rhs) => { |
| is_non_failing(&lhs.expr, rules, trace) || is_non_failing(&rhs.expr, rules, trace) |
| } |
| // it either always fail |
| // or always match at least a character |
| ParserExpr::Range(_, _) => false, |
| ParserExpr::PeekSlice(_, _) => { |
| // the slice being checked is not non_failing since every |
| // PUSH is being checked (assumption 4) and the expr |
| // of a PUSH has to be non_failing. |
| // BUG: if the slice is of size 0, or the stack is not large |
| // enough it might be non-failing |
| false |
| } |
| ParserExpr::RepExact(ref inner, min) |
| | ParserExpr::RepMin(ref inner, min) |
| | ParserExpr::RepMinMax(ref inner, min, _) => { |
| min == 0 || is_non_failing(&inner.expr, rules, trace) |
| } |
| // BUG: the predicate may always fail, resulting in this expr non_failing |
| // ex of always failing predicates : |
| // @{EOI ~ ANY | ANY ~ SOI | &("A") ~ &("B") | 'z'..'a'} |
| ParserExpr::NegPred(_) => false, |
| ParserExpr::RepOnce(ref inner) => is_non_failing(&inner.expr, rules, trace), |
| ParserExpr::Push(ref inner) | ParserExpr::PosPred(ref inner) => { |
| is_non_failing(&inner.expr, rules, trace) |
| } |
| #[cfg(feature = "grammar-extras")] |
| ParserExpr::NodeTag(ref inner, _) => is_non_failing(&inner.expr, rules, trace), |
| } |
| } |
| |
| fn validate_repetition<'a, 'i: 'a>(rules: &'a [ParserRule<'i>]) -> Vec<Error<Rule>> { |
| let mut result = vec![]; |
| let map = to_hash_map(rules); |
| |
| for rule in rules { |
| let mut errors = rule.node |
| .clone() |
| .filter_map_top_down(|node| match node.expr { |
| ParserExpr::Rep(ref other) |
| | ParserExpr::RepOnce(ref other) |
| | ParserExpr::RepMin(ref other, _) => { |
| if is_non_failing(&other.expr, &map, &mut vec![]) { |
| Some(Error::new_from_span( |
| ErrorVariant::CustomError { |
| message: |
| "expression inside repetition cannot fail and will repeat \ |
| infinitely" |
| .to_owned() |
| }, |
| node.span |
| )) |
| } else if is_non_progressing(&other.expr, &map, &mut vec![]) { |
| Some(Error::new_from_span( |
| ErrorVariant::CustomError { |
| message: |
| "expression inside repetition is non-progressing and will repeat \ |
| infinitely" |
| .to_owned(), |
| }, |
| node.span |
| )) |
| } else { |
| None |
| } |
| } |
| _ => None |
| }); |
| |
| result.append(&mut errors); |
| } |
| |
| result |
| } |
| |
| fn validate_choices<'a, 'i: 'a>(rules: &'a [ParserRule<'i>]) -> Vec<Error<Rule>> { |
| let mut result = vec![]; |
| let map = to_hash_map(rules); |
| |
| for rule in rules { |
| let mut errors = rule |
| .node |
| .clone() |
| .filter_map_top_down(|node| match node.expr { |
| ParserExpr::Choice(ref lhs, _) => { |
| let node = match lhs.expr { |
| ParserExpr::Choice(_, ref rhs) => rhs, |
| _ => lhs, |
| }; |
| |
| if is_non_failing(&node.expr, &map, &mut vec![]) { |
| Some(Error::new_from_span( |
| ErrorVariant::CustomError { |
| message: |
| "expression cannot fail; following choices cannot be reached" |
| .to_owned(), |
| }, |
| node.span, |
| )) |
| } else { |
| None |
| } |
| } |
| _ => None, |
| }); |
| |
| result.append(&mut errors); |
| } |
| |
| result |
| } |
| |
| fn validate_whitespace_comment<'a, 'i: 'a>(rules: &'a [ParserRule<'i>]) -> Vec<Error<Rule>> { |
| let map = to_hash_map(rules); |
| |
| rules |
| .iter() |
| .filter_map(|rule| { |
| if rule.name == "WHITESPACE" || rule.name == "COMMENT" { |
| if is_non_failing(&rule.node.expr, &map, &mut vec![]) { |
| Some(Error::new_from_span( |
| ErrorVariant::CustomError { |
| message: format!( |
| "{} cannot fail and will repeat infinitely", |
| &rule.name |
| ), |
| }, |
| rule.node.span, |
| )) |
| } else if is_non_progressing(&rule.node.expr, &map, &mut vec![]) { |
| Some(Error::new_from_span( |
| ErrorVariant::CustomError { |
| message: format!( |
| "{} is non-progressing and will repeat infinitely", |
| &rule.name |
| ), |
| }, |
| rule.node.span, |
| )) |
| } else { |
| None |
| } |
| } else { |
| None |
| } |
| }) |
| .collect() |
| } |
| |
| fn validate_left_recursion<'a, 'i: 'a>(rules: &'a [ParserRule<'i>]) -> Vec<Error<Rule>> { |
| left_recursion(to_hash_map(rules)) |
| } |
| |
| fn to_hash_map<'a, 'i: 'a>(rules: &'a [ParserRule<'i>]) -> HashMap<String, &'a ParserNode<'i>> { |
| rules.iter().map(|r| (r.name.clone(), &r.node)).collect() |
| } |
| |
| fn left_recursion<'a, 'i: 'a>(rules: HashMap<String, &'a ParserNode<'i>>) -> Vec<Error<Rule>> { |
| fn check_expr<'a, 'i: 'a>( |
| node: &'a ParserNode<'i>, |
| rules: &'a HashMap<String, &ParserNode<'i>>, |
| trace: &mut Vec<String>, |
| ) -> Option<Error<Rule>> { |
| match node.expr.clone() { |
| ParserExpr::Ident(other) => { |
| if trace[0] == other { |
| trace.push(other); |
| let chain = trace |
| .iter() |
| .map(|ident| ident.as_ref()) |
| .collect::<Vec<_>>() |
| .join(" -> "); |
| |
| return Some(Error::new_from_span( |
| ErrorVariant::CustomError { |
| message: format!( |
| "rule {} is left-recursive ({}); pest::pratt_parser might be useful \ |
| in this case", |
| node.span.as_str(), |
| chain |
| ) |
| }, |
| node.span |
| )); |
| } |
| |
| if !trace.contains(&other) { |
| if let Some(node) = rules.get(&other) { |
| trace.push(other); |
| let result = check_expr(node, rules, trace); |
| trace.pop().unwrap(); |
| |
| return result; |
| } |
| } |
| |
| None |
| } |
| ParserExpr::Seq(ref lhs, ref rhs) => { |
| if is_non_failing(&lhs.expr, rules, &mut vec![trace.last().unwrap().clone()]) { |
| check_expr(rhs, rules, trace) |
| } else { |
| check_expr(lhs, rules, trace) |
| } |
| } |
| ParserExpr::Choice(ref lhs, ref rhs) => { |
| check_expr(lhs, rules, trace).or_else(|| check_expr(rhs, rules, trace)) |
| } |
| ParserExpr::Rep(ref node) => check_expr(node, rules, trace), |
| ParserExpr::RepOnce(ref node) => check_expr(node, rules, trace), |
| ParserExpr::Opt(ref node) => check_expr(node, rules, trace), |
| ParserExpr::PosPred(ref node) => check_expr(node, rules, trace), |
| ParserExpr::NegPred(ref node) => check_expr(node, rules, trace), |
| ParserExpr::Push(ref node) => check_expr(node, rules, trace), |
| _ => None, |
| } |
| } |
| |
| let mut errors = vec![]; |
| |
| for (name, node) in &rules { |
| let name = name.clone(); |
| |
| if let Some(error) = check_expr(node, &rules, &mut vec![name]) { |
| errors.push(error); |
| } |
| } |
| |
| errors |
| } |
| |
| #[cfg(test)] |
| mod tests { |
| use super::super::parser::{consume_rules, PestParser}; |
| use super::super::unwrap_or_report; |
| use super::*; |
| use pest::Parser; |
| |
| #[test] |
| #[should_panic(expected = "grammar error |
| |
| --> 1:1 |
| | |
| 1 | ANY = { \"a\" } |
| | ^-^ |
| | |
| = ANY is a pest keyword")] |
| fn pest_keyword() { |
| let input = "ANY = { \"a\" }"; |
| unwrap_or_report(validate_pairs( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| #[should_panic(expected = "grammar error |
| |
| --> 1:13 |
| | |
| 1 | a = { \"a\" } a = { \"a\" } |
| | ^ |
| | |
| = rule a already defined")] |
| fn already_defined() { |
| let input = "a = { \"a\" } a = { \"a\" }"; |
| unwrap_or_report(validate_pairs( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| #[should_panic(expected = "grammar error |
| |
| --> 1:7 |
| | |
| 1 | a = { b } |
| | ^ |
| | |
| = rule b is undefined")] |
| fn undefined() { |
| let input = "a = { b }"; |
| unwrap_or_report(validate_pairs( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| fn valid_recursion() { |
| let input = "a = { \"\" ~ \"a\"? ~ \"a\"* ~ (\"a\" | \"b\") ~ a }"; |
| unwrap_or_report(consume_rules( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| #[should_panic(expected = "grammar error |
| |
| --> 1:16 |
| | |
| 1 | WHITESPACE = { \"\" } |
| | ^^ |
| | |
| = WHITESPACE cannot fail and will repeat infinitely")] |
| fn non_failing_whitespace() { |
| let input = "WHITESPACE = { \"\" }"; |
| unwrap_or_report(consume_rules( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| #[should_panic(expected = "grammar error |
| |
| --> 1:13 |
| | |
| 1 | COMMENT = { SOI } |
| | ^-^ |
| | |
| = COMMENT is non-progressing and will repeat infinitely")] |
| fn non_progressing_comment() { |
| let input = "COMMENT = { SOI }"; |
| unwrap_or_report(consume_rules( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| fn non_progressing_empty_string() { |
| assert!(is_non_failing( |
| &ParserExpr::Insens("".into()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_progressing( |
| &ParserExpr::Str("".into()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| } |
| |
| #[test] |
| fn progressing_non_empty_string() { |
| assert!(!is_non_progressing( |
| &ParserExpr::Insens("non empty".into()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(!is_non_progressing( |
| &ParserExpr::Str("non empty".into()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| } |
| |
| #[test] |
| fn non_progressing_soi_eoi() { |
| assert!(is_non_progressing( |
| &ParserExpr::Ident("SOI".into()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_progressing( |
| &ParserExpr::Ident("EOI".into()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| } |
| |
| #[test] |
| fn non_progressing_predicates() { |
| let progressing = ParserExpr::Str("A".into()); |
| |
| assert!(is_non_progressing( |
| &ParserExpr::PosPred(Box::new(ParserNode { |
| expr: progressing.clone(), |
| span: Span::new(" ", 0, 1).unwrap(), |
| })), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_progressing( |
| &ParserExpr::NegPred(Box::new(ParserNode { |
| expr: progressing, |
| span: Span::new(" ", 0, 1).unwrap(), |
| })), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| } |
| |
| #[test] |
| fn non_progressing_0_length_repetitions() { |
| let input_progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str("A".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| |
| assert!(!is_non_progressing( |
| &input_progressing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| assert!(is_non_progressing( |
| &ParserExpr::Rep(input_progressing_node.clone()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_progressing( |
| &ParserExpr::Opt(input_progressing_node.clone()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_progressing( |
| &ParserExpr::RepExact(input_progressing_node.clone(), 0), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_progressing( |
| &ParserExpr::RepMin(input_progressing_node.clone(), 0), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_progressing( |
| &ParserExpr::RepMax(input_progressing_node.clone(), 0), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_progressing( |
| &ParserExpr::RepMax(input_progressing_node.clone(), 17), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| assert!(is_non_progressing( |
| &ParserExpr::RepMinMax(input_progressing_node.clone(), 0, 12), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| } |
| |
| #[test] |
| fn non_progressing_nonzero_repetitions_with_non_progressing_expr() { |
| let a = ""; |
| let non_progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str(a.into()), |
| span: Span::new(a, 0, 0).unwrap(), |
| }); |
| let exact = ParserExpr::RepExact(non_progressing_node.clone(), 7); |
| let min = ParserExpr::RepMin(non_progressing_node.clone(), 23); |
| let minmax = ParserExpr::RepMinMax(non_progressing_node.clone(), 12, 13); |
| let reponce = ParserExpr::RepOnce(non_progressing_node); |
| |
| assert!(is_non_progressing(&exact, &HashMap::new(), &mut Vec::new())); |
| assert!(is_non_progressing(&min, &HashMap::new(), &mut Vec::new())); |
| assert!(is_non_progressing( |
| &minmax, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_progressing( |
| &reponce, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| } |
| |
| #[test] |
| fn progressing_repetitions() { |
| let a = "A"; |
| let input_progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str(a.into()), |
| span: Span::new(a, 0, 1).unwrap(), |
| }); |
| let exact = ParserExpr::RepExact(input_progressing_node.clone(), 1); |
| let min = ParserExpr::RepMin(input_progressing_node.clone(), 2); |
| let minmax = ParserExpr::RepMinMax(input_progressing_node.clone(), 4, 5); |
| let reponce = ParserExpr::RepOnce(input_progressing_node); |
| |
| assert!(!is_non_progressing( |
| &exact, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(!is_non_progressing(&min, &HashMap::new(), &mut Vec::new())); |
| assert!(!is_non_progressing( |
| &minmax, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(!is_non_progressing( |
| &reponce, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| } |
| |
| #[test] |
| fn non_progressing_push() { |
| let a = ""; |
| let non_progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str(a.into()), |
| span: Span::new(a, 0, 0).unwrap(), |
| }); |
| let push = ParserExpr::Push(non_progressing_node.clone()); |
| |
| assert!(is_non_progressing(&push, &HashMap::new(), &mut Vec::new())); |
| } |
| |
| #[test] |
| fn progressing_push() { |
| let a = "i'm make progress"; |
| let progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str(a.into()), |
| span: Span::new(a, 0, 1).unwrap(), |
| }); |
| let push = ParserExpr::Push(progressing_node.clone()); |
| |
| assert!(!is_non_progressing(&push, &HashMap::new(), &mut Vec::new())); |
| } |
| |
| #[test] |
| fn node_tag_forwards_is_non_progressing() { |
| let progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str("i'm make progress".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| assert!(!is_non_progressing( |
| &progressing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| let non_progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str("".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| assert!(is_non_progressing( |
| &non_progressing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| #[cfg(feature = "grammar-extras")] |
| { |
| let progressing = ParserExpr::NodeTag(progressing_node.clone(), "TAG".into()); |
| let non_progressing = ParserExpr::NodeTag(non_progressing_node.clone(), "TAG".into()); |
| |
| assert!(!is_non_progressing( |
| &progressing, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_progressing( |
| &non_progressing, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| } |
| } |
| |
| #[test] |
| fn progressing_range() { |
| let progressing = ParserExpr::Range("A".into(), "Z".into()); |
| let failing_is_progressing = ParserExpr::Range("Z".into(), "A".into()); |
| |
| assert!(!is_non_progressing( |
| &progressing, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(!is_non_progressing( |
| &failing_is_progressing, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| } |
| |
| #[test] |
| fn progressing_choice() { |
| let left_progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str("i'm make progress".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| assert!(!is_non_progressing( |
| &left_progressing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| let right_progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Ident("DROP".into()), |
| span: Span::new("DROP", 0, 3).unwrap(), |
| }); |
| |
| assert!(!is_non_progressing( |
| &ParserExpr::Choice(left_progressing_node, right_progressing_node), |
| &HashMap::new(), |
| &mut Vec::new() |
| )) |
| } |
| |
| #[test] |
| fn non_progressing_choices() { |
| let left_progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str("i'm make progress".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| |
| assert!(!is_non_progressing( |
| &left_progressing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| let left_non_progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str("".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| |
| assert!(is_non_progressing( |
| &left_non_progressing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| let right_progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Ident("DROP".into()), |
| span: Span::new("DROP", 0, 3).unwrap(), |
| }); |
| |
| assert!(!is_non_progressing( |
| &right_progressing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| let right_non_progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Opt(Box::new(ParserNode { |
| expr: ParserExpr::Str(" ".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| })), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| |
| assert!(is_non_progressing( |
| &right_non_progressing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| assert!(is_non_progressing( |
| &ParserExpr::Choice(left_non_progressing_node.clone(), right_progressing_node), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_progressing( |
| &ParserExpr::Choice(left_progressing_node, right_non_progressing_node.clone()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_progressing( |
| &ParserExpr::Choice(left_non_progressing_node, right_non_progressing_node), |
| &HashMap::new(), |
| &mut Vec::new() |
| )) |
| } |
| |
| #[test] |
| fn non_progressing_seq() { |
| let left_non_progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str("".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| |
| let right_non_progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Opt(Box::new(ParserNode { |
| expr: ParserExpr::Str(" ".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| })), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| |
| assert!(is_non_progressing( |
| &ParserExpr::Seq(left_non_progressing_node, right_non_progressing_node), |
| &HashMap::new(), |
| &mut Vec::new() |
| )) |
| } |
| |
| #[test] |
| fn progressing_seqs() { |
| let left_progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str("i'm make progress".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| |
| assert!(!is_non_progressing( |
| &left_progressing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| let left_non_progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str("".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| |
| assert!(is_non_progressing( |
| &left_non_progressing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| let right_progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Ident("DROP".into()), |
| span: Span::new("DROP", 0, 3).unwrap(), |
| }); |
| |
| assert!(!is_non_progressing( |
| &right_progressing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| let right_non_progressing_node = Box::new(ParserNode { |
| expr: ParserExpr::Opt(Box::new(ParserNode { |
| expr: ParserExpr::Str(" ".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| })), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| |
| assert!(is_non_progressing( |
| &right_non_progressing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| assert!(!is_non_progressing( |
| &ParserExpr::Seq(left_non_progressing_node, right_progressing_node.clone()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(!is_non_progressing( |
| &ParserExpr::Seq(left_progressing_node.clone(), right_non_progressing_node), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(!is_non_progressing( |
| &ParserExpr::Seq(left_progressing_node, right_progressing_node), |
| &HashMap::new(), |
| &mut Vec::new() |
| )) |
| } |
| |
| #[test] |
| fn progressing_stack_operations() { |
| assert!(!is_non_progressing( |
| &ParserExpr::Ident("DROP".into()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(!is_non_progressing( |
| &ParserExpr::Ident("PEEK".into()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(!is_non_progressing( |
| &ParserExpr::Ident("POP".into()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )) |
| } |
| |
| #[test] |
| fn non_failing_string() { |
| let insens = ParserExpr::Insens("".into()); |
| let string = ParserExpr::Str("".into()); |
| |
| assert!(is_non_failing(&insens, &HashMap::new(), &mut Vec::new())); |
| |
| assert!(is_non_failing(&string, &HashMap::new(), &mut Vec::new())) |
| } |
| |
| #[test] |
| fn failing_string() { |
| assert!(!is_non_failing( |
| &ParserExpr::Insens("i may fail!".into()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(!is_non_failing( |
| &ParserExpr::Str("failure is not fatal".into()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )) |
| } |
| |
| #[test] |
| fn failing_stack_operations() { |
| assert!(!is_non_failing( |
| &ParserExpr::Ident("DROP".into()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(!is_non_failing( |
| &ParserExpr::Ident("POP".into()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(!is_non_failing( |
| &ParserExpr::Ident("PEEK".into()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )) |
| } |
| |
| #[test] |
| fn non_failing_zero_length_repetitions() { |
| let failing = Box::new(ParserNode { |
| expr: ParserExpr::Range("A".into(), "B".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| assert!(!is_non_failing( |
| &failing.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_failing( |
| &ParserExpr::Opt(failing.clone()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_failing( |
| &ParserExpr::Rep(failing.clone()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_failing( |
| &ParserExpr::RepExact(failing.clone(), 0), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_failing( |
| &ParserExpr::RepMin(failing.clone(), 0), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_failing( |
| &ParserExpr::RepMax(failing.clone(), 0), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_failing( |
| &ParserExpr::RepMax(failing.clone(), 22), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_failing( |
| &ParserExpr::RepMinMax(failing.clone(), 0, 73), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| } |
| |
| #[test] |
| fn non_failing_non_zero_repetitions_with_non_failing_expr() { |
| let non_failing = Box::new(ParserNode { |
| expr: ParserExpr::Opt(Box::new(ParserNode { |
| expr: ParserExpr::Range("A".into(), "B".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| })), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| assert!(is_non_failing( |
| &non_failing.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_failing( |
| &ParserExpr::RepOnce(non_failing.clone()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_failing( |
| &ParserExpr::RepExact(non_failing.clone(), 1), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_failing( |
| &ParserExpr::RepMin(non_failing.clone(), 6), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_failing( |
| &ParserExpr::RepMinMax(non_failing.clone(), 32, 73), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| } |
| |
| #[test] |
| #[cfg(feature = "grammar-extras")] |
| fn failing_non_zero_repetitions() { |
| let failing = Box::new(ParserNode { |
| expr: ParserExpr::NodeTag( |
| Box::new(ParserNode { |
| expr: ParserExpr::Range("A".into(), "B".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }), |
| "Tag".into(), |
| ), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| assert!(!is_non_failing( |
| &failing.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(!is_non_failing( |
| &ParserExpr::RepOnce(failing.clone()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(!is_non_failing( |
| &ParserExpr::RepExact(failing.clone(), 3), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(!is_non_failing( |
| &ParserExpr::RepMin(failing.clone(), 14), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(!is_non_failing( |
| &ParserExpr::RepMinMax(failing.clone(), 47, 73), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| } |
| |
| #[test] |
| fn failing_choice() { |
| let left_failing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str("i'm a failure".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| assert!(!is_non_failing( |
| &left_failing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| let right_failing_node = Box::new(ParserNode { |
| expr: ParserExpr::Ident("DROP".into()), |
| span: Span::new("DROP", 0, 3).unwrap(), |
| }); |
| |
| assert!(!is_non_failing( |
| &ParserExpr::Choice(left_failing_node, right_failing_node), |
| &HashMap::new(), |
| &mut Vec::new() |
| )) |
| } |
| |
| #[test] |
| fn non_failing_choices() { |
| let left_failing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str("i'm a failure".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| |
| assert!(!is_non_failing( |
| &left_failing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| let left_non_failing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str("".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| |
| assert!(is_non_failing( |
| &left_non_failing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| let right_failing_node = Box::new(ParserNode { |
| expr: ParserExpr::Ident("DROP".into()), |
| span: Span::new("DROP", 0, 3).unwrap(), |
| }); |
| |
| assert!(!is_non_failing( |
| &right_failing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| let right_non_failing_node = Box::new(ParserNode { |
| expr: ParserExpr::Opt(Box::new(ParserNode { |
| expr: ParserExpr::Str(" ".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| })), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| |
| assert!(is_non_failing( |
| &right_non_failing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| assert!(is_non_failing( |
| &ParserExpr::Choice(left_non_failing_node.clone(), right_failing_node), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_failing( |
| &ParserExpr::Choice(left_failing_node, right_non_failing_node.clone()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_failing( |
| &ParserExpr::Choice(left_non_failing_node, right_non_failing_node), |
| &HashMap::new(), |
| &mut Vec::new() |
| )) |
| } |
| |
| #[test] |
| fn non_failing_seq() { |
| let left_non_failing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str("".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| |
| let right_non_failing_node = Box::new(ParserNode { |
| expr: ParserExpr::Opt(Box::new(ParserNode { |
| expr: ParserExpr::Str(" ".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| })), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| |
| assert!(is_non_failing( |
| &ParserExpr::Seq(left_non_failing_node, right_non_failing_node), |
| &HashMap::new(), |
| &mut Vec::new() |
| )) |
| } |
| |
| #[test] |
| fn failing_seqs() { |
| let left_failing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str("i'm a failure".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| |
| assert!(!is_non_failing( |
| &left_failing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| let left_non_failing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str("".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| |
| assert!(is_non_failing( |
| &left_non_failing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| let right_failing_node = Box::new(ParserNode { |
| expr: ParserExpr::Ident("DROP".into()), |
| span: Span::new("DROP", 0, 3).unwrap(), |
| }); |
| |
| assert!(!is_non_failing( |
| &right_failing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| let right_non_failing_node = Box::new(ParserNode { |
| expr: ParserExpr::Opt(Box::new(ParserNode { |
| expr: ParserExpr::Str(" ".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| })), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| |
| assert!(is_non_failing( |
| &right_non_failing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| assert!(!is_non_failing( |
| &ParserExpr::Seq(left_non_failing_node, right_failing_node.clone()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(!is_non_failing( |
| &ParserExpr::Seq(left_failing_node.clone(), right_non_failing_node), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(!is_non_failing( |
| &ParserExpr::Seq(left_failing_node, right_failing_node), |
| &HashMap::new(), |
| &mut Vec::new() |
| )) |
| } |
| |
| #[test] |
| fn failing_range() { |
| let failing = ParserExpr::Range("A".into(), "Z".into()); |
| let always_failing = ParserExpr::Range("Z".into(), "A".into()); |
| |
| assert!(!is_non_failing(&failing, &HashMap::new(), &mut Vec::new())); |
| assert!(!is_non_failing( |
| &always_failing, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| } |
| |
| #[test] |
| fn _push_node_tag_pos_pred_forwarding_is_non_failing() { |
| let failing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str("i'm a failure".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| assert!(!is_non_failing( |
| &failing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| let non_failing_node = Box::new(ParserNode { |
| expr: ParserExpr::Str("".into()), |
| span: Span::new(" ", 0, 1).unwrap(), |
| }); |
| assert!(is_non_failing( |
| &non_failing_node.clone().expr, |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| #[cfg(feature = "grammar-extras")] |
| { |
| assert!(!is_non_failing( |
| &ParserExpr::NodeTag(failing_node.clone(), "TAG".into()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_failing( |
| &ParserExpr::NodeTag(non_failing_node.clone(), "TAG".into()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| } |
| |
| assert!(!is_non_failing( |
| &ParserExpr::Push(failing_node.clone()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_failing( |
| &ParserExpr::Push(non_failing_node.clone()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| |
| assert!(!is_non_failing( |
| &ParserExpr::PosPred(failing_node.clone()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| assert!(is_non_failing( |
| &ParserExpr::PosPred(non_failing_node.clone()), |
| &HashMap::new(), |
| &mut Vec::new() |
| )); |
| } |
| |
| #[test] |
| #[should_panic(expected = "grammar error |
| |
| --> 1:7 |
| | |
| 1 | a = { (\"\")* } |
| | ^---^ |
| | |
| = expression inside repetition cannot fail and will repeat infinitely")] |
| fn non_failing_repetition() { |
| let input = "a = { (\"\")* }"; |
| unwrap_or_report(consume_rules( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| #[should_panic(expected = "grammar error |
| |
| --> 1:18 |
| | |
| 1 | a = { \"\" } b = { a* } |
| | ^^ |
| | |
| = expression inside repetition cannot fail and will repeat infinitely")] |
| fn indirect_non_failing_repetition() { |
| let input = "a = { \"\" } b = { a* }"; |
| unwrap_or_report(consume_rules( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| #[should_panic(expected = "grammar error |
| |
| --> 1:20 |
| | |
| 1 | a = { \"a\" ~ (\"b\" ~ (\"\")*) } |
| | ^---^ |
| | |
| = expression inside repetition cannot fail and will repeat infinitely")] |
| fn deep_non_failing_repetition() { |
| let input = "a = { \"a\" ~ (\"b\" ~ (\"\")*) }"; |
| unwrap_or_report(consume_rules( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| #[should_panic(expected = "grammar error |
| |
| --> 1:7 |
| | |
| 1 | a = { (\"\" ~ &\"a\" ~ !\"a\" ~ (SOI | EOI))* } |
| | ^-------------------------------^ |
| | |
| = expression inside repetition is non-progressing and will repeat infinitely")] |
| fn non_progressing_repetition() { |
| let input = "a = { (\"\" ~ &\"a\" ~ !\"a\" ~ (SOI | EOI))* }"; |
| unwrap_or_report(consume_rules( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| #[should_panic(expected = "grammar error |
| |
| --> 1:20 |
| | |
| 1 | a = { !\"a\" } b = { a* } |
| | ^^ |
| | |
| = expression inside repetition is non-progressing and will repeat infinitely")] |
| fn indirect_non_progressing_repetition() { |
| let input = "a = { !\"a\" } b = { a* }"; |
| unwrap_or_report(consume_rules( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| #[should_panic(expected = "grammar error |
| |
| --> 1:7 |
| | |
| 1 | a = { a } |
| | ^ |
| | |
| = rule a is left-recursive (a -> a); pest::pratt_parser might be useful in this case")] |
| fn simple_left_recursion() { |
| let input = "a = { a }"; |
| unwrap_or_report(consume_rules( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| #[should_panic(expected = "grammar error |
| |
| --> 1:7 |
| | |
| 1 | a = { b } b = { a } |
| | ^ |
| | |
| = rule b is left-recursive (b -> a -> b); pest::pratt_parser might be useful in this case |
| |
| --> 1:17 |
| | |
| 1 | a = { b } b = { a } |
| | ^ |
| | |
| = rule a is left-recursive (a -> b -> a); pest::pratt_parser might be useful in this case")] |
| fn indirect_left_recursion() { |
| let input = "a = { b } b = { a }"; |
| unwrap_or_report(consume_rules( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| #[should_panic(expected = "grammar error |
| |
| --> 1:39 |
| | |
| 1 | a = { \"\" ~ \"a\"? ~ \"a\"* ~ (\"a\" | \"\") ~ a } |
| | ^ |
| | |
| = rule a is left-recursive (a -> a); pest::pratt_parser might be useful in this case")] |
| fn non_failing_left_recursion() { |
| let input = "a = { \"\" ~ \"a\"? ~ \"a\"* ~ (\"a\" | \"\") ~ a }"; |
| unwrap_or_report(consume_rules( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| #[should_panic(expected = "grammar error |
| |
| --> 1:13 |
| | |
| 1 | a = { \"a\" | a } |
| | ^ |
| | |
| = rule a is left-recursive (a -> a); pest::pratt_parser might be useful in this case")] |
| fn non_primary_choice_left_recursion() { |
| let input = "a = { \"a\" | a }"; |
| unwrap_or_report(consume_rules( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| #[should_panic(expected = "grammar error |
| |
| --> 1:7 |
| | |
| 1 | a = { \"a\"* | \"a\" | \"b\" } |
| | ^--^ |
| | |
| = expression cannot fail; following choices cannot be reached")] |
| fn lhs_non_failing_choice() { |
| let input = "a = { \"a\"* | \"a\" | \"b\" }"; |
| unwrap_or_report(consume_rules( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| #[should_panic(expected = "grammar error |
| |
| --> 1:13 |
| | |
| 1 | a = { \"a\" | \"a\"* | \"b\" } |
| | ^--^ |
| | |
| = expression cannot fail; following choices cannot be reached")] |
| fn lhs_non_failing_choice_middle() { |
| let input = "a = { \"a\" | \"a\"* | \"b\" }"; |
| unwrap_or_report(consume_rules( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| #[should_panic(expected = "grammar error |
| |
| --> 1:7 |
| | |
| 1 | a = { b | \"a\" } b = { \"b\"* | \"c\" } |
| | ^ |
| | |
| = expression cannot fail; following choices cannot be reached |
| |
| --> 1:23 |
| | |
| 1 | a = { b | \"a\" } b = { \"b\"* | \"c\" } |
| | ^--^ |
| | |
| = expression cannot fail; following choices cannot be reached")] |
| fn lhs_non_failing_nested_choices() { |
| let input = "a = { b | \"a\" } b = { \"b\"* | \"c\" }"; |
| unwrap_or_report(consume_rules( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| |
| #[test] |
| fn skip_can_be_defined() { |
| let input = "skip = { \"\" }"; |
| unwrap_or_report(consume_rules( |
| PestParser::parse(Rule::grammar_rules, input).unwrap(), |
| )); |
| } |
| } |
