Bugs in 2.x relative import '.' and 1.x bytecode

uncompyle6/scanner.py

@@ -229,6 +229,8 @@ class Scanner(object):
         # Locally we use list for more convenient iteration using indices
         linestarts = list(self.opc.findlinestarts(code_obj))
         self.linestarts = dict(linestarts)
+        if not self.linestarts:
+            return []
 
         # 'List-map' which shows line number of current op and offset of
         # first op on following line, given offset of op as index

uncompyle6/scanners/scanner2.py

@@ -522,7 +522,7 @@ class Scanner2(Scanner):
         for s in stmt_list:
             if code[s] == self.opc.JUMP_ABSOLUTE and s not in pass_stmts:
                 target = self.get_target(s)
-                if target > s or self.lines[last_stmt].l_no == self.lines[s].l_no:
+                if target > s or (self.lines and self.lines[last_stmt].l_no == self.lines[s].l_no):
                     stmts.remove(s)
                     continue
                 j = self.prev[s]
@@ -623,6 +623,7 @@ class Scanner2(Scanner):
         parent = self.structs[0]
         start = parent["start"]
         end = parent["end"]
+        next_line_byte = end
 
         # Pick inner-most parent for our offset
         for struct in self.structs:
@@ -651,7 +652,8 @@ class Scanner2(Scanner):
             if setup_target != loop_end_offset:
                 self.fixed_jumps[offset] = loop_end_offset
 
-            (line_no, next_line_byte) = self.lines[offset]
+            if self.lines:
+                (line_no, next_line_byte) = self.lines[offset]
 
             # jump_back_offset is the instruction after the SETUP_LOOP
             # where we iterate back to.

uncompyle6/scanners/scanner26.py

@@ -113,7 +113,7 @@ class Scanner26(scan.Scanner2):
         i = self.next_stmt[last_stmt]
         replace = {}
         while i < codelen - 1:
-            if self.lines[last_stmt].next > i:
+            if self.lines and self.lines[last_stmt].next > i:
                 # Distinguish "print ..." from "print ...,"
                 if self.code[last_stmt] == self.opc.PRINT_ITEM:
                     if self.code[i] == self.opc.PRINT_ITEM:

uncompyle6/semantics/customize26_27.py

@@ -30,10 +30,10 @@ def customize_for_version26_27(self, version):
     ########################################
     if version > (2, 6):
         TABLE_DIRECT.update({
-            'except_cond2':	( '%|except %c as %c:\n', 1, 5 ),
+            "except_cond2":	( "%|except %c as %c:\n", 1, 5 ),
             # When a generator is a single parameter of a function,
             # it doesn't need the surrounding parenethesis.
-            'call_generator': ('%c%P', 0, (1, -1, ', ', 100)),
+            "call_generator": ('%c%P', 0, (1, -1, ', ', 100)),
         })
     else:
         TABLE_DIRECT.update({
@@ -60,3 +60,14 @@ def customize_for_version26_27(self, version):
 
         self.default(node)
     self.n_call = n_call
+
+    def n_import_from(node):
+        import_name = node[2]
+        if import_name == "IMPORT_NAME" and import_name.pattr == "":
+            fmt = "%|from . import %c\n"
+            self.template_engine(
+                (fmt, (3, "importlist")), node
+            )
+            self.prune()
+        self.default(node)
+    self.n_import_from = n_import_from