Fix ASN.1 lexer: recognize minus sign and fix range operator (#3060)

h1whelan · claude · web-flow · commit c3d93adb9827 · 2026-03-25T23:19:39.000+01:00
Two fixes for the ASN.1 lexer: 1. Add `-` to the operator pattern so negative values in constraints like `(-50..150)` are tokenized correctly instead of producing an error token for the minus sign. 2. Require at least one digit after the decimal point in float literals (`\d+\.\d+` instead of `\d+\.\d*`). This prevents `50..150` from being incorrectly tokenized as float `50.` + punctuation `.` + int `150`, instead of the correct int `50` + range `..` + int `150`. Fixes #3014. Co-authored-by: h1whelan <h1whelan@users.noreply.github.com> Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
diff --git a/pygments/lexers/asn1.py b/pygments/lexers/asn1.py
@@ -136,7 +136,7 @@ class Asn1Lexer(RegexLexer):
             (r'--.*$', Comment.Single),
             (r'/\*', Comment.Multiline, 'comment'),
             #  Numbers:
-            (r'\d+\.\d*([eE][-+]?\d+)?', Number.Float),
+            (r'\d+\.\d+([eE][-+]?\d+)?', Number.Float),
             (r'\d+', Number.Integer),
             # Identifier:
             (r"&?[a-z][-a-zA-Z0-9]*[a-zA-Z0-9]\b", Name.Variable),
@@ -155,7 +155,7 @@ class Asn1Lexer(RegexLexer):
             # Type identifier:
             (r"&?[A-Z][-a-zA-Z0-9]*[a-zA-Z0-9]\b", Name.Type),
             # Operators:
-            (r"(::=|\.\.\.|\.\.|\[\[|\]\]|\||\^)", Operator),
+            (r"(::=|\.\.\.|\.\.|\[\[|\]\]|\||\^|-)", Operator),
             # Punctuation:
             (r"(\.|,|\{|\}|\(|\)|\[|\])", Punctuation),
             # String:
diff --git a/tests/examplefiles/asn1/x509.asn1.output b/tests/examplefiles/asn1/x509.asn1.output
diff --git a/tests/snippets/asn1/negative-integer.txt b/tests/snippets/asn1/negative-integer.txt
@@ -0,0 +1,19 @@
+---input---
+Temperature ::= INTEGER (-50..150)  -- Temperature in Celsius
+
+---tokens---
+'Temperature' Name.Type
+' '           Text.Whitespace
+'::='         Operator
+' '           Text.Whitespace
+'INTEGER'     Keyword.Type
+' '           Text.Whitespace
+'('           Punctuation
+'-'           Operator
+'50'          Literal.Number.Integer
+'..'          Operator
+'150'         Literal.Number.Integer
+')'           Punctuation
+'  '          Text.Whitespace
+'-- Temperature in Celsius' Comment.Single
+'\n'          Text.Whitespace
