New version for skipPos, major fix to Python redundancy check

Author: agroce

setup.py

@@ -5,7 +5,7 @@
 
 setup(
     name='universalmutator',
-    version='1.1.8',
+    version='1.1.9',
     description='Universal regexp-based mutation tool',
     long_description_content_type="text/markdown",
     long_description=open('README.md').read(),

universalmutator/python_handler.py

@@ -2,6 +2,7 @@
 import os
 import sys
 import py_compile
+import uuid
 
 
 def buildCode(c):
@@ -28,19 +29,33 @@ def buildCode(c):
 
 
 def getPythonCode(fname):
-    # Courtesy of Ned Batchelder, just get the code object from the .pyc file
+    # from https://stackoverflow.com/questions/32562163/how-can-i-understand-a-pyc-file-content
+    header_sizes = [
+        # (size, first version this applies to)
+        # pyc files were introduced in 0.9.2 way, way back in June 1991.
+        (8,  (0, 9, 2)),  # 2 bytes magic number, \r\n, 4 bytes UNIX timestamp
+        (12, (3, 6)),     # added 4 bytes file size
+        # bytes 4-8 are flags, meaning of 9-16 depends on what flags are set
+        # bit 0 not set: 9-12 timestamp, 13-16 file size
+        # bit 0 set: 9-16 file hash (SipHash-2-4, k0 = 4 bytes of the file, k1 = 0)
+        (16, (3, 7)),     # inserted 4 bytes bit flag field at 4-8 
+        # future version may add more bytes still, at which point we can extend
+        # this table. It is correct for Python versions up to 3.9
+    ]
+    header_size = next(s for s, v in reversed(header_sizes) if sys.version_info >= v)
+
     with open(fname, "rb") as f:
-        f.read(4)
-        f.read(4)
-        if sys.version_info >= (3, 3):
-            f.read(4)
+        metadata = f.read(header_size)  # first header_size bytes are metadata
         try:
-            code = marshal.load(f)
-        except (EOFError, TypeError, ValueError):
-            with open(fname, "rb") as fRetry:
-                fRetry.read(16)
-                code = marshal.load(fRetry)
-    return buildCode(code)
+            code = marshal.load(f)          # rest is a marshalled code object
+        except:
+            print("WARNING: UNABLE TO MARSHAL CODE FROM PYC FILE!")
+            return(uuid.uuid4())
+    if ("code" not in str(type(code))):
+        print("WARNING: INVALID CODE OBJECT READ FROM PYC FILE!")
+        return(uuid.uuid4())        
+    b = buildCode(code)
+    return b
 
 
 def handler(tmpMutantName, mutant, sourceFile, uniqueMutants):

universalmutator/static/python.rules

@@ -39,3 +39,5 @@ True ==> False
 '.+' ==> ''
 
 @.* ==> 
+
+# ==> SKIP_MUTATING_REST