experimental: support for debug info (#118)

Signed-off-by: wpt967 <matt.aw@parity.io>
Signed-off-by: xermicus <cyrill@parity.io>

crates/solidity/src/yul/lexer/token/lexeme/comment/multi_line.rs

@@ -19,12 +19,20 @@ impl Comment {
         let end_position = input.find(Self::END).unwrap_or(input.len());
         let input = &input[..end_position];
 
-        let length = end_position + Self::END.len();
-        let lines = input.matches('\n').count();
+        let length = (end_position + Self::END.len())
+            .try_into()
+            .expect("the YUL should be of reasonable size");
+        let lines = input
+            .matches('\n')
+            .count()
+            .try_into()
+            .expect("the YUL should be of reasonable size");
         let columns = match input.rfind('\n') {
             Some(new_line) => end_position - (new_line + 1),
             None => end_position,
-        };
+        }
+        .try_into()
+        .expect("the YUL should be of reasonable size");
 
         Token::new(Location::new(lines, columns), Lexeme::Comment, length)
     }

crates/solidity/src/yul/lexer/token/lexeme/comment/single_line.rs

@@ -17,7 +17,9 @@ impl Comment {
     /// Returns the comment's length, including the trimmed whitespace around it.
     pub fn parse(input: &str) -> Token {
         let end_position = input.find(Self::END).unwrap_or(input.len());
-        let length = end_position + Self::END.len();
+        let length = (end_position + Self::END.len())
+            .try_into()
+            .expect("the YUL should be of reasonable size");
 
         Token::new(Location::new(1, 1), Lexeme::Comment, length)
     }

crates/solidity/src/yul/lexer/token/lexeme/identifier.rs

@@ -26,7 +26,10 @@ impl Identifier {
         let end = input.find(Self::cannot_continue).unwrap_or(input.len());
 
         let inner = input[..end].to_string();
-        let length = inner.len();
+        let length = inner
+            .len()
+            .try_into()
+            .expect("the YUL should be of reasonable size");
 
         if let Some(token) = Keyword::parse(inner.as_str()) {
             return Some(token);

crates/solidity/src/yul/lexer/token/lexeme/keyword.rs

@@ -58,6 +58,9 @@ impl Keyword {
         if length != input.len() {
             return None;
         }
+        let length = length
+            .try_into()
+            .expect("the YUL should be of reasonable size");
 
         Some(Token::new(Location::new(0, length), lexeme, length))
     }

crates/solidity/src/yul/lexer/token/lexeme/literal/integer.rs

@@ -54,6 +54,10 @@ impl Integer {
             return None;
         };
 
+        let length = length
+            .try_into()
+            .expect("the YUL should be of reasonable size");
+
         let token = Token::new(
             Location::new(0, length),
             Lexeme::Literal(Literal::Integer(value)),

crates/solidity/src/yul/lexer/token/lexeme/literal/string.rs

@@ -69,6 +69,9 @@ impl String {
             .to_owned();
 
         let literal = Self::new(string, is_hex_string);
+        let length = length
+            .try_into()
+            .expect("the YUL should be of reasonable size");
 
         Some(Token::new(
             Location::new(0, length),