Closes #892: fix overzealous analyse_text of the SourcesListLexer.

Also remove any "default" return from analyse_text methods.

3 files changed, 6 insertions, 9 deletions

diff --git a/pygments/lexers/basic.py b/pygments/lexers/basic.py
index b3733e6f..a5e79e5e 100644
--- a/pygments/lexers/basic.py
+++ b/pygments/lexers/basic.py
@@ -354,7 +354,7 @@ class CbmBasicV2Lexer(RegexLexer):
         # if it starts with a line number, it shouldn't be a "modern" Basic
         # like VB.net
         if re.match(r'\d+', text):
-            return True
+            return 0.2
 
 
 class QBasicLexer(RegexLexer):
@@ -496,4 +496,5 @@ class QBasicLexer(RegexLexer):
     }
 
     def analyse_text(text):
-        return 0.2
+        if '$DYNAMIC' in text or '$STATIC' in text:
+            return 0.9
diff --git a/pygments/lexers/dsls.py b/pygments/lexers/dsls.py
index db2e2d48..e059ecfd 100644
--- a/pygments/lexers/dsls.py
+++ b/pygments/lexers/dsls.py
@@ -300,8 +300,6 @@ class RslLexer(RegexLexer):
         """
         if re.search(r'scheme\s*.*?=\s*class\s*type', text, re.I) is not None:
             return 1.0
-        else:
-            return 0.01
 
 
 class MscgenLexer(RegexLexer):
diff --git a/pygments/lexers/installers.py b/pygments/lexers/installers.py
index b76db0a9..54369da1 100644
--- a/pygments/lexers/installers.py
+++ b/pygments/lexers/installers.py
@@ -258,12 +258,10 @@ class SourcesListLexer(RegexLexer):
     }
 
     def analyse_text(text):
-        for line in text.split('\n'):
+        for line in text.splitlines():
             line = line.strip()
-            if not (line.startswith('#') or line.startswith('deb ') or
-                    line.startswith('deb-src ') or not line):
-                return False
-        return True
+            if line.startswith('deb ') or line.startswith('deb-src '):
+                return True
 
 
 class DebianControlLexer(RegexLexer):