Improve various analyse_text methods.task/add-analyze-text

* Make Perl less confident in presence of :=.
* Improve brainfuck check to not parse the whole input.
* Improve Unicon by matching \self, /self
* Fix Ezhil not matching against the input text

1 files changed, 15 insertions, 1 deletions

diff --git a/pygments/lexers/perl.py b/pygments/lexers/perl.py
index 741de3fd..95fb94e7 100644
--- a/pygments/lexers/perl.py
+++ b/pygments/lexers/perl.py
@@ -208,8 +208,18 @@ class PerlLexer(RegexLexer):
     def analyse_text(text):
         if shebang_matches(text, r'perl'):
             return True
+
+        result = 0
+
         if re.search(r'(?:my|our)\s+[$@%(]', text):
-            return 0.9
+            result += 0.9
+
+        if ':=' in text:
+            # := is not valid Perl, but it appears in unicon, so we should
+            # become less confident if we think we found Perl with :=
+            result /= 2
+
+        return result
 
 
 class Perl6Lexer(ExtendedRegexLexer):
@@ -711,6 +721,10 @@ class Perl6Lexer(ExtendedRegexLexer):
                 continue
             break
 
+        if ':=' in text:
+            # Same logic as above for PerlLexer
+            rating /= 2
+
         return rating
 
     def __init__(self, **options):