🐛 Parser error with greater/less operators

[blutorange]

Environment information

CLI:
  Version:                      1.4.1
  Color support:                true

Platform:
  CPU Architecture:             x86_64
  OS:                           linux

Environment:
  BIOME_LOG_DIR:                unset
  NO_COLOR:                     unset
  TERM:                         "xterm-256color"
  JS_RUNTIME_VERSION:           unset
  JS_RUNTIME_NAME:              unset
  NODE_PACKAGE_MANAGER:         unset

Biome Configuration:
  Status:                       Loaded successfully
  Formatter disabled:           false
  Linter disabled:              false
  Organize imports disabled:    true
  VCS disabled:                 true

Workspace:
  Open Documents:               0

What happened?

While I was migrating our code base to biome, I came across a file where biome reported syntax errors. After taking a look, I found what is probably a bug in the parser (It was some legacy code that I fixed by now, which also got rid of the parser error.)

A simplified version of the code the shows the parser bug is:

function getDataSourcesForParameterCount(ranges) {
  return 0 < $.grep(ranges, (range) => {return 0 >= 1;}).length;
}

This should be legal TypeScript code, but biome gives several parser errors.

When you replace 0 >= 1 with e.g. 1, the parser errors disappear. It also disappears when you remove the 0 < at the beginning or move it to the end (> 0); or when you change < to >.

You can see this in the playground with the latest version. It only happens when TypeScript is enabled, with our without JSX enabled. It might be related to type arguments in functions (e.g. microsoft/TypeScript#36662)

https://biomejs.dev/playground/?unsafeParameterDecoratorsEnabled=false&allowComments=false&code=CgBmAHUAbgBjAHQAaQBvAG4AIABnAGUAdABEAGEAdABhAFMAbwB1AHIAYwBlAHMARgBvAHIAUABhAHIAYQBtAGUAdABlAHIAQwBvAHUAbgB0ACgAcgBhAG4AZwBlAHMAKQAgAHsACgAgACAAcgBlAHQAdQByAG4AIAAwACAAPAAgACQALgBnAHIAZQBwACgAcgBhAG4AZwBlAHMALAAgACgAcgBhAG4AZwBlACkAIAA9AD4AIAB7AHIAZQB0AHUAcgBuACAAMAAgAD4APQAgADEAOwB9ACkALgBsAGUAbgBnAHQAaAA7AAoAfQAKAA%3D%3D&jsx=false

An even simpler example:

const a = 0 < (0 >= 1);

The parser seems interpret as a literal 0, followed by a type argument < (0 >:

0: JS_MODULE@0..25
  0: (empty)
  1: (empty)
  2: JS_DIRECTIVE_LIST@0..0
  3: JS_MODULE_ITEM_LIST@0..23
    0: JS_VARIABLE_STATEMENT@0..21
      0: JS_VARIABLE_DECLARATION@0..21
        0: (empty)
        1: CONST_KW@0..6 "const" [] [Whitespace(" ")]
        2: JS_VARIABLE_DECLARATOR_LIST@6..21
          0: JS_VARIABLE_DECLARATOR@6..21
            0: JS_IDENTIFIER_BINDING@6..8
              0: IDENT@6..8 "a" [] [Whitespace(" ")]
            1: (empty)
            2: JS_INITIALIZER_CLAUSE@8..21
              0: EQ@8..10 "=" [] [Whitespace(" ")]
              1: JS_ASSIGNMENT_EXPRESSION@10..21
                0: JS_BOGUS_ASSIGNMENT@10..18
                  0: JS_NUMBER_LITERAL_EXPRESSION@10..12
                    0: JS_NUMBER_LITERAL@10..12 "0" [] [Whitespace(" ")]
                  1: TS_TYPE_ARGUMENTS@12..18
                    0: L_ANGLE@12..14 "<" [] [Whitespace(" ")]
                    1: TS_TYPE_ARGUMENT_LIST@14..17
                      0: TS_PARENTHESIZED_TYPE@14..17
                        0: L_PAREN@14..15 "(" [] []
                        1: TS_NUMBER_LITERAL_TYPE@15..17
                          0: (empty)
                          1: JS_NUMBER_LITERAL@15..17 "0" [] [Whitespace(" ")]
                        2: (empty)
                    2: R_ANGLE@17..18 ">" [] []
                1: EQ@18..20 "=" [] [Whitespace(" ")]
                2: JS_NUMBER_LITERAL_EXPRESSION@20..21
                  0: JS_NUMBER_LITERAL@20..21 "1" [] []
      1: (empty)
    1: JS_BOGUS_STATEMENT@21..22
      0: R_PAREN@21..22 ")" [] []
    2: JS_EMPTY_STATEMENT@22..23
      0: SEMICOLON@22..23 ";" [] []
  4: EOF@23..25 "" [Newline("\n"), Newline("\n")] []

Expected result

It should parse the code successfully.

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