Incorrect line number reported when file has LF for line separator

[l-cornelius-dol]

Similarly to #37 I now find that under some conditions the line number is incorrect when the file uses LF for line separators. Specifically, it again appears related to single-line comments, this time, being out by -1 for every SLC which is followed by at least one blank line. In the examples following, there is a missing = in the function's variable assignment.

Out by -4:

0001 // Single line comment
0002
0003 // Single line comment
0004 
0005 // Single line comment
0006
0007 // Single line comment
0008
0009 function handleAutocomplete() {
0010    var prp                          this.props; // <= error on this line
0011
0012    for(let xa=0; xa<100; xa++) {;}
0013    }

ERROR : C:/Data/user/lawrence/programming/build/esvalidate/test-lf.js:~: [6:41]: Unexpected token: 'this'

Out by -3:

0001 // Single line comment
0002
0003 // Single line comment
0004 
0005 // Single line comment
0006
0007 function handleAutocomplete() {
0008    var prp                          this.props; // <= error on this line
0009
0010    for(let xa=0; xa<100; xa++) {;}
0011    }

ERROR : C:/Data/user/lawrence/programming/build/esvalidate/test-lf.js:~: [5:41]: Unexpected token: 'this'

and so on.

This does not happen for CRLF line endings. I can induce any syntax error in a file with SLC's and it is consistently misreported.

[KFlash]

@lawrence-dol I'm not online the next days due to RL stuff. Could you try to experiment with it and try to send a PR? It should be an very easy change.

[l-cornelius-dol]

@KFlash : I'd like to, but I am not set up with the tool chain for developing TS, so pragmatically, I've no realistic path to testing any changes. I could experiment with the generated JS, but that won't be useful as a direct PR, only as a reference as to what to change.

[KFlash]

A reference is okay. Then I can do the changes when I get back online. Maybe late sunday. Depends if there is any plane delays.

[l-cornelius-dol]

@KFlash : The following changes seem to be working as expected. The problem was the special handling LF in comments.

But please note that was expecting to find the tracking of current line and column at a single, high-level location -- so it's very possible that the problem is resolved for comments but there could still be similar problems elsewhere.

First I modified advanceChar to normalize CR, CRLF, LFCR sequences as if they were a single LF. This then absorbs CR chars unless they are by themselves and allows the rest of the code to be concerned only with LF as the "current" character. There is also no need then for state flag 4 since we no longer care whether the previous character was a CR. It should handle any combination of line-breaks, including mixed CR/CRLF/LFCR/LF.

  const CR=0x0D,LF=0x0A;

  ...

  function advanceChar(parser) {
      parser.column++;
      parser.currentChar = parser.source.charCodeAt(++parser.index);

      if(parser.index < parser.end) {
          let cur=parser.currentChar, nxt = parser.source.charCodeAt(parser.index + 1);
          if((cur == CR && nxt == LF) || (cur == LF && nxt == CR)) {
              parser.currentChar = LF;
              parser.index++;
          }
          else if(cur == CR) {
              parser.currentChar = LF;
          }
      }
      return parser.currentChar;
  }

I renamed scanNewLine to consumeLineBreak because I found the latter to more clearly indicate that the current character would be advanced. Also, advanceChar needed to be used instead of manually loading the next character so that correct CR/LF handling was done (there may be other places where this is a concern). Also, note the tweak to move the advanceChar to the end, after resetting the column; without that I was out-by-one on the column.

  function consumeLineBreak(parser) {
      parser.flags |= 1;
      parser.column = 0;
      parser.line++;
      parser.currentChar = advanceChar(parser);
  }

Next I changed the main state handling for line breaks to reflect this abstraction:

  function scanSingleToken(parser, context, state) {
      ...
          if (char <= 0x7e) {
              const token = TokenLookup[char];
              switch (token) {
                  ...
                  case 127:
                  case 133:
                      consumeLineBreak(parser);
                      state |= 1;
                      break;
                  default:
              }
          }
          else {
              if ((char ^ 8232) <= 1) {
                  consumeLineBreak(parser);
                  state |= 1;
                  continue;
              }
      ...

And now comment handling for line breaks was much simpler:

  function skipSingleLineComment(parser, state, type) {
      const { index } = parser;
      while (parser.index < parser.end) {
          if ((CharTypes[parser.currentChar] & 8) || ((parser.currentChar ^ 8232) <= 1)) {
              consumeLineBreak(parser);
              return state | 1;
          }
          else {
              advanceChar(parser);
          }
      }
      if (parser.onComment)
          parser.onComment(CommentTypes[type & 0xff], parser.source.slice(index, parser.index), index, parser.index);
      return state | 1;
  }

  function skipMultiLineComment(parser, state) {
      const { index } = parser;
      while (parser.index < parser.end) {
          while (parser.currentChar === 42) {
              if (advanceChar(parser) === 47) {
                  advanceChar(parser);
                  if (parser.onComment)
                      parser.onComment(CommentTypes[1 & 0xff], parser.source.slice(index, parser.index - 2), index, parser.index);
                  return state;
              }
          }
          if ((CharTypes[parser.currentChar] & 8) || ((parser.currentChar ^ 8232) <= 1)) {
              consumeLineBreak(parser);
              state |= 1;
          }
          else {
              advanceChar(parser);
          }
      }
      report(parser, 16);
  }

And that seems to have resolved the problem.

[KFlash]

is this still an issue?

[l-cornelius-dol]

@KFlash : Based on the current version from unpkg, 1.7.2, yes it is still an issue. None of these changes are present in 1.7.2. (I am running a version of 1.7.2 which I modified as shown above.)

[l-cornelius-dol]

@KFlash : Hi there. Is there any update on this?

[KFlash]

AH! Sorry. Been busy with some RL stuff so I haven't had time. But just grab v. 1.80 from NPM and it should have been solved now.

[l-cornelius-dol]

@KFlash : Version 1.8.0 with the does not work when the line endings are CRLF, but it does for LF. The issue is possibly that consumeLineFeed and consumeLineBreak do not use advanceChar, which I found was necessary in order to properly handle runs of line breaks.

Note that my changes eliminated the need for two functions and state flag 4 as well as consolidating the parser switch cases for 127 and 133.

[KFlash]

I more or less copied your code above. I will double check

[KFlash]

@lawrence-dol Pushed an update. Also see this https://github.com/meriyah/meriyah/blob/master/src/lexer/common.ts#L34

[l-cornelius-dol]

@KFlash : Ha ha. I'm not sure if I should be complimented, or worried.

I'm using unpkg.com to get the iife. Is that easy to make available? Otherwise, I can tweak my local copy to match that change.

[l-cornelius-dol]

OK, if I take 1.8.0 from unpkg.com and patch the function per your reference with the two advanceChar functions, then both tests return an incorrect location. The CRLF line and column are wrong, and the LF code has the column wrong (both columns are out by -1, giving 36 instead of 37).

My full test sources now include both SLC and MLC variations:

// Single line comment

// Single line comment

// Single line comment

// Single line comment

/**/

/* MLC on one line */

/*
MLC
on
multiple
lines
*/

function handleAutocomplete() {
    var prp                         this.props;

    for(let xa=0; xa<100; xa++) {;}
    }

[KFlash]

Can't you try v. 1.8.2 ? That version includes an exact replicate of your code. Doesn't iife exist already?

[l-cornelius-dol]

Sorry, my bad; I refreshed the page, but forgot the unpkg redirects to a version specific URL. I've just pulled 1.8.2, and I get no output at all. \_O.O_/

[l-cornelius-dol]

That said, 1.8.2 does not replicate my code. It still has two consume functions, and uses state & 4 to reset the column and advance the line number. My code dispensed with that entirely. I also didn't need the split advance function since it's correct to increment the column when consuming a linefeed, which had just reset the column to 0 (else you're out by one to the left).

[l-cornelius-dol]

I can probably make the changes to the TS code, now that I've become more familiar to the code base (just can't build and test it). That might be enough for a good-enough patch?

[KFlash]

It's ok. I can build and test it and give you feedback

[l-cornelius-dol]

OK, I'll look into after work tonight.

[l-cornelius-dol]

@KFlash : I've made the changes, but I don't have permission create a pull request on the repo. How would you like me to proceed?

[aladdin-add]

you can fork the repo. refs: https://help.github.com/en/articles/creating-a-pull-request-from-a-fork

[l-cornelius-dol]

OK, that's done. Hopefully correctly. The pull request shows up on your repo.

[KFlash]

@lawrence-dol Any update on your progress regarding this issue?

[l-cornelius-dol]

Not yet; I have a customer-down issue at work and a couple other high-priority tasks.

After resetting the initial value for line to 0 (changing it to 1 is surely the reason for the failed tests) the line number for my test code with comments is out by 1. My gut says that the extraction of a character from the source (i.e. anything that logically causes the column to advance, and then the line if a break is read) needs to be consolidated to the single advanceChar function, which is responsible to for (a) extracting the next character, (b) incrementing and resetting the column number, (c) incrementing the line number, and (d) dealing with the various possible line break characters and pairs.

I'm not sure how feasible it's going to be for me to make the fix without the ability to take the TS code and produce JS which I can run to test. Currently I am making changes in the generated JS, and then remaking them in the TS -- which works for highly surgical changes, but not for more extensive ones.

[KFlash]

Take your time :) Do it if and when you can.
I have some huge critical RL issues to handle now so I have no time for anything anymore it seems.

cc / @nchanged

[nchanged]

Take it easy Kenny :)

[KFlash]

@lawrence-dol Have you looked into this issue any further?

Btw. Look at this gist. This is my private locale code and not open sourced. Do you see the solution I'm using for location tracking?

I may think you should try if that solution works for you and solve all issues, and if it does can you copy & paste it and create a PR? I'm not sure when I will be active again.

Note that in that gist there are no column increment / decrement, and I simply divide the colum and line pos from the current index on line break.

I think this lines is of interest.

Also note that single line comment are only 3 lines of code :) No magic done in the hot loop as in current Meriyah source.

[l-cornelius-dol]

@KFlash Can you generate the IIFE with this so I can try it and see? Or is there a simple way that I can do so (bearing in mind that I don't have node.js, or any TS build tools installed)? I presume that this passes current tests, so I can check with my known failing sources.

[KFlash]

I can't generate an IIFE with it because it was just an code snippet and not used anywhere.
I still think your solution is the best one, but you need to fix the 93 broken tests before anything else.

[KFlash]

@lawrence-dol I'm friend of K.F and just pushed a change. I noticed the line count was wrong. Reported 12 where it should have been 18. This happened because of missing line pos counting in lexer. It's all fixed and I pushed a minor version to NPM.

Your example code have been used as a test - located here and the line and column pos is in line with other parsers.

[l-cornelius-dol]

For the test I provided, it's necessary to have the blank lines after the comments to trip the fault. It's also important to test LF, CR, LFCR & CRLF line endings.

Also, this update has reverted the column to point to the end of the faulting token, instead of the start. This is corrected by using linePos and columnPos for the exception.

[l-cornelius-dol]

@KFlash : Is it possible that the test failures related to column number are the result of changing the column to the start of the token instead of the end of it?

[GuyLewin]

@lawrence-dol I tried to reproduce by parsing the following snippet:
// Single line comment\r\n// Single line comment\r\n// Single line comment\r\n// Single line comment\r\nfunction handleAutocomplete() {\r\n var prp = this.props; // some error here\r\n\r\n for(let xa=0; xa<100; xa++) {;}\r\n }

And it looks as though it parsed nicely, to:

{
 "body": [
   {
     "async": false
     "body": {
       "body": [
         {
           "declarations": [
             {
               "id": {
                 "loc": {
                   "end": {
                     "column": 10
                     "line": 11
                   }
                   "start": {
                     "column": 7
                     "line": 11
                   }
                 }
                 "name": "prp"
                 "type": "Identifier"
               }
               "init": {
                 "computed": false
                 "loc": {
                   "end": {
                     "column": 23
                     "line": 11
                   }
                   "start": {
                     "column": 13
                     "line": 11
                   }
                 }
                 "object": {
                   "loc": {
                     "end": {
                       "column": 17
                       "line": 11
                     }
                     "start": {
                       "column": 13
                       "line": 11
                     }
                   }
                   "type": "ThisExpression"
                 }
                 "property": {
                   "loc": {
                     "end": {
                       "column": 23
                       "line": 11
                     }
                     "start": {
                       "column": 18
                       "line": 11
                     }
                   }
                   "name": "props"
                   "type": "Identifier"
                 }
                 "type": "MemberExpression"
               }
               "loc": {
                 "end": {
                   "column": 23
                   "line": 11
                 }
                 "start": {
                   "column": 7
                   "line": 11
                 }
               }
               "type": "VariableDeclarator"
             }
           ]
           "kind": "var"
           "loc": {
             "end": {
               "column": 24
               "line": 11
             }
             "start": {
               "column": 3
               "line": 11
             }
           }
           "type": "VariableDeclaration"
         }
         {
           "body": {
             "body": [
               {
                 "loc": {
                   "end": {
                     "column": 33
                     "line": 15
                   }
                   "start": {
                     "column": 32
                     "line": 15
                   }
                 }
                 "type": "EmptyStatement"
               }
             ]
             "loc": {
               "end": {
                 "column": 34
                 "line": 15
               }
               "start": {
                 "column": 31
                 "line": 15
               }
             }
             "type": "BlockStatement"
           }
           "init": {
             "declarations": [
               {
                 "id": {
                   "loc": {
                     "end": {
                       "column": 13
                       "line": 15
                     }
                     "start": {
                       "column": 11
                       "line": 15
                     }
                   }
                   "name": "xa"
                   "type": "Identifier"
                 }
                 "init": {
                   "loc": {
                     "end": {
                       "column": 15
                       "line": 15
                     }
                     "start": {
                       "column": 14
                       "line": 15
                     }
                   }
                   "type": "Literal"
                   "value": 0
                 }
                 "loc": {
                   "end": {
                     "column": 15
                     "line": 15
                   }
                   "start": {
                     "column": 11
                     "line": 15
                   }
                 }
                 "type": "VariableDeclarator"
               }
             ]
             "kind": "let"
             "loc": {
               "end": {
                 "column": 15
                 "line": 15
               }
               "start": {
                 "column": 7
                 "line": 15
               }
             }
             "type": "VariableDeclaration"
           }
           "loc": {
             "end": {
               "column": 34
               "line": 15
             }
             "start": {
               "column": 3
               "line": 15
             }
           }
           "test": {
             "left": {
               "loc": {
                 "end": {
                   "column": 19
                   "line": 15
                 }
                 "start": {
                   "column": 17
                   "line": 15
                 }
               }
               "name": "xa"
               "type": "Identifier"
             }
             "loc": {
               "end": {
                 "column": 23
                 "line": 15
               }
               "start": {
                 "column": 17
                 "line": 15
               }
             }
             "operator": "<"
             "right": {
               "loc": {
                 "end": {
                   "column": 23
                   "line": 15
                 }
                 "start": {
                   "column": 20
                   "line": 15
                 }
               }
               "type": "Literal"
               "value": 100
             }
             "type": "BinaryExpression"
           }
           "type": "ForStatement"
           "update": {
             "argument": {
               "loc": {
                 "end": {
                   "column": 27
                   "line": 15
                 }
                 "start": {
                   "column": 25
                   "line": 15
                 }
               }
               "name": "xa"
               "type": "Identifier"
             }
             "loc": {
               "end": {
                 "column": 29
                 "line": 15
               }
               "start": {
                 "column": 25
                 "line": 15
               }
             }
             "operator": "++"
             "prefix": false
             "type": "UpdateExpression"
           }
         }
       ]
       "loc": {
         "end": {
           "column": 4
           "line": 17
         }
         "start": {
           "column": 30
           "line": 9
         }
       }
       "type": "BlockStatement"
     }
     "generator": false
     "id": {
       "loc": {
         "end": {
           "column": 27
           "line": 9
         }
         "start": {
           "column": 9
           "line": 9
         }
       }
       "name": "handleAutocomplete"
       "type": "Identifier"
     }
     "loc": {
       "end": {
         "column": 4
         "line": 17
       }
       "start": {
         "column": 0
         "line": 9
       }
     }
     "params": []
     "type": "FunctionDeclaration"
   }
 {
 "body": [
   {
     "async": false
     "body": {
       "body": [
         {
           "declarations": [
             {
               "id": {
                 "loc": {
                   "end": {
                     "column": 10
                     "line": 11
                   }
                   "start": {
                     "column": 7
                     "line": 11
                   }
                 }
                 "name": "prp"
                 "type": "Identifier"
               }
               "init": {
                 "computed": false
                 "loc": {
                   "end": {
                     "column": 23
                     "line": 11
                   }
                   "start": {
                     "column": 13
                     "line": 11
                   }
                 }
                 "object": {
                   "loc": {
                     "end": {
                       "column": 17
                       "line": 11
                     }
                     "start": {
                       "column": 13
                       "line": 11
                     }
                   }
                   "type": "ThisExpression"
                 }
                 "property": {
                   "loc": {
                     "end": {
                       "column": 23
                       "line": 11
                     }
                     "start": {
                       "column": 18
                       "line": 11
                     }
                   }
                   "name": "props"
                   "type": "Identifier"
                 }
                 "type": "MemberExpression"
               }
               "loc": {
                 "end": {
                   "column": 23
                   "line": 11
                 }
                 "start": {
                   "column": 7
                   "line": 11
                 }
               }
               "type": "VariableDeclarator"
             }
           ]
           "kind": "var"
           "loc": {
             "end": {
               "column": 24
               "line": 11
             }
             "start": {
               "column": 3
               "line": 11
             }
           }
           "type": "VariableDeclaration"
         }
         {
           "body": {
             "body": [
               {
                 "loc": {
                   "end": {
                     "column": 33
                     "line": 15
                   }
                   "start": {
                     "column": 32
                     "line": 15
                   }
                 }
                 "type": "EmptyStatement"
               }
             ]
             "loc": {
               "end": {
                 "column": 34
                 "line": 15
               }
               "start": {
                 "column": 31
                 "line": 15
               }
             }
             "type": "BlockStatement"
           }
           "init": {
             "declarations": [
               {
                 "id": {
                   "loc": {
                     "end": {
                       "column": 13
                       "line": 15
                     }
                     "start": {
                       "column": 11
                       "line": 15
                     }
                   }
                   "name": "xa"
                   "type": "Identifier"
                 }
                 "init": {
                   "loc": {
                     "end": {
                       "column": 15
                       "line": 15
                     }
                     "start": {
                       "column": 14
                       "line": 15
                     }
                   }
                   "type": "Literal"
                   "value": 0
                 }
                 "loc": {
                   "end": {
                     "column": 15
                     "line": 15
                   }
                   "start": {
                     "column": 11
                     "line": 15
                   }
                 }
                 "type": "VariableDeclarator"
               }
             ]
             "kind": "let"
             "loc": {
               "end": {
                 "column": 15
                 "line": 15
               }
               "start": {
                 "column": 7
                 "line": 15
               }
             }
             "type": "VariableDeclaration"
           }
           "loc": {
             "end": {
               "column": 34
               "line": 15
             }
             "start": {
               "column": 3
               "line": 15
             }
           }
           "test": {
             "left": {
               "loc": {
                 "end": {
                   "column": 19
                   "line": 15
                 }
                 "start": {
                   "column": 17
                   "line": 15
                 }
               }
               "name": "xa"
               "type": "Identifier"
             }
             "loc": {
               "end": {
                 "column": 23
                 "line": 15
               }
               "start": {
                 "column": 17
                 "line": 15
               }
             }
             "operator": "<"
             "right": {
               "loc": {
                 "end": {
                   "column": 23
                   "line": 15
                 }
                 "start": {
                   "column": 20
                   "line": 15
                 }
               }
               "type": "Literal"
               "value": 100
             }
             "type": "BinaryExpression"
           }
           "type": "ForStatement"
           "update": {
             "argument": {
               "loc": {
                 "end": {
                   "column": 27
                   "line": 15
                 }
                 "start": {
                   "column": 25
                   "line": 15
                 }
               }
               "name": "xa"
               "type": "Identifier"
             }
             "loc": {
               "end": {
                 "column": 29
                 "line": 15
               }
               "start": {
                 "column": 25
                 "line": 15
               }
             }
             "operator": "++"
             "prefix": false
             "type": "UpdateExpression"
           }
         }
       ]
       "loc": {
         "end": {
           "column": 4
           "line": 17
         }
         "start": {
           "column": 30
           "line": 9
         }
       }
       "type": "BlockStatement"
     }
     "generator": false
     "id": {
       "loc": {
         "end": {
           "column": 27
           "line": 9
         }
         "start": {
           "column": 9
           "line": 9
         }
       }
       "name": "handleAutocomplete"
       "type": "Identifier"
     }
     "loc": {
       "end": {
         "column": 4
         "line": 17
       }
       "start": {
         "column": 0
         "line": 9
       }
     }
     "params": []
     "type": "FunctionDeclaration"
   }
 {
 "body": [
   {
     "async": false
     "body": {
       "body": [
         {
           "declarations": [
             {
               "id": {
                 "loc": {
                   "end": {
                     "column": 10
                     "line": 11
                   }
                   "start": {
                     "column": 7
                     "line": 11
                   }
                 }
                 "name": "prp"
                 "type": "Identifier"
               }
               "init": {
                 "computed": false
                 "loc": {
                   "end": {
                     "column": 23
                     "line": 11
                   }
                   "start": {
                     "column": 13
                     "line": 11
                   }
                 }
                 "object": {
                   "loc": {
                     "end": {
                       "column": 17
                       "line": 11
                     }
                     "start": {
                       "column": 13
                       "line": 11
                     }
                   }
                   "type": "ThisExpression"
                 }
                 "property": {
                   "loc": {
                     "end": {
                       "column": 23
                       "line": 11
                     }
                     "start": {
                       "column": 18
                       "line": 11
                     }
                   }
                   "name": "props"
                   "type": "Identifier"
                 }
                 "type": "MemberExpression"
               }
               "loc": {
                 "end": {
                   "column": 23
                   "line": 11
                 }
                 "start": {
                   "column": 7
                   "line": 11
                 }
               }
               "type": "VariableDeclarator"
             }
           ]
           "kind": "var"
           "loc": {
             "end": {
               "column": 24
               "line": 11
             }
             "start": {
               "column": 3
               "line": 11
             }
           }
           "type": "VariableDeclaration"
         }
         {
           "body": {
             "body": [
               {
                 "loc": {
                   "end": {
                     "column": 33
                     "line": 15
                   }
                   "start": {
                     "column": 32
                     "line": 15
                   }
                 }
                 "type": "EmptyStatement"
               }
             ]
             "loc": {
               "end": {
                 "column": 34
                 "line": 15
               }
               "start": {
                 "column": 31
                 "line": 15
               }
             }
             "type": "BlockStatement"
           }
           "init": {
             "declarations": [
               {
                 "id": {
                   "loc": {
                     "end": {
                       "column": 13
                       "line": 15
                     }
                     "start": {
                       "column": 11
                       "line": 15
                     }
                   }
                   "name": "xa"
                   "type": "Identifier"
                 }
                 "init": {
                   "loc": {
                     "end": {
                       "column": 15
                       "line": 15
                     }
                     "start": {
                       "column": 14
                       "line": 15
                     }
                   }
                   "type": "Literal"
                   "value": 0
                 }
                 "loc": {
                   "end": {
                     "column": 15
                     "line": 15
                   }
                   "start": {
                     "column": 11
                     "line": 15
                   }
                 }
                 "type": "VariableDeclarator"
               }
             ]
             "kind": "let"
             "loc": {
               "end": {
                 "column": 15
                 "line": 15
               }
               "start": {
                 "column": 7
                 "line": 15
               }
             }
             "type": "VariableDeclaration"
           }
           "loc": {
             "end": {
               "column": 34
               "line": 15
             }
             "start": {
               "column": 3
               "line": 15
             }
           }
           "test": {
             "left": {
               "loc": {
                 "end": {
                   "column": 19
                   "line": 15
                 }
                 "start": {
                   "column": 17
                   "line": 15
                 }
               }
               "name": "xa"
               "type": "Identifier"
             }
             "loc": {
               "end": {
                 "column": 23
                 "line": 15
               }
               "start": {
                 "column": 17
                 "line": 15
               }
             }
             "operator": "<"
             "right": {
               "loc": {
                 "end": {
                   "column": 23
                   "line": 15
                 }
                 "start": {
                   "column": 20
                   "line": 15
                 }
               }
               "type": "Literal"
               "value": 100
             }
             "type": "BinaryExpression"
           }
           "type": "ForStatement"
           "update": {
             "argument": {
               "loc": {
                 "end": {
                   "column": 27
                   "line": 15
                 }
                 "start": {
                   "column": 25
                   "line": 15
                 }
               }
               "name": "xa"
               "type": "Identifier"
             }
             "loc": {
               "end": {
                 "column": 29
                 "line": 15
               }
               "start": {
                 "column": 25
                 "line": 15
               }
             }
             "operator": "++"
             "prefix": false
             "type": "UpdateExpression"
           }
         }
       ]
       "loc": {
         "end": {
           "column": 4
           "line": 17
         }
         "start": {
           "column": 30
           "line": 9
         }
       }
       "type": "BlockStatement"
     }
     "generator": false
     "id": {
       "loc": {
         "end": {
           "column": 27
           "line": 9
         }
         "start": {
           "column": 9
           "line": 9
         }
       }
       "name": "handleAutocomplete"
       "type": "Identifier"
     }
     "loc": {
       "end": {
         "column": 4
         "line": 17
       }
       "start": {
         "column": 0
         "line": 9
       }
     }
     "params": []
     "type": "FunctionDeclaration"
   }
 ]]]```

Can you elaborate on the issue, give broken example?

[l-cornelius-dol]

@GuyLewin

I tried to reproduce by parsing the following snippet:
// Single line comment\r\n// Single line comment\r\n// Single line comment\r\n// Single line comment\r\nfunction handleAutocomplete() {\r\n var prp = this.props; // some error here\r\n\r\n for(let xa=0; xa<100; xa++) {;}\r\n }

And it looks as though it parsed nicely, to:
...
Can you elaborate on the issue, give broken example?

Yes, you need to use LF line breaks, not CRLF, using current versions. Older versions had a problem with CRLF, but not LF.

[GuyLewin]

@lawrence-dol I think I saw what you meant and fixed it in #52. I added a test to make sure your snippet with LF and CRLF parses exactly the same.

[KFlash]

@lawrence-dol Can you confirm that this changes works for you now?

[l-cornelius-dol]

Apologies for not commenting, but yes, I tested this as soon as it landed and confirmed correct reporting in my two test files. When I came back here it was closed, so I figured we were good. Appreciate you checking up on it.