Prevent exceptions when running fix on dialect fixtures

src/sqlfluff/core/rules/analysis/select.py

@@ -80,7 +80,7 @@ def get_select_statement_info(
     for ref in reference_buffer.copy():
         ref_path = segment.path_to(ref)
         # is it in a subselect? i.e. a select which isn't this one.
-        if any(
+        if ref_path and any(
             seg.is_type("select_statement") and seg is not segment for seg in ref_path
         ):
             reference_buffer.remove(ref)

src/sqlfluff/core/rules/base.py

@@ -802,28 +802,33 @@ def _choose_anchor_segment(
 
         anchor: BaseSegment = segment
         child: BaseSegment = segment
-        for seg in context.parent_stack[0].path_to(segment)[1:-1][::-1]:
-            # Which lists of children to check against.
-            children_lists: List[List[BaseSegment]] = []
-            if filter_meta:
-                # Optionally check against filtered (non-meta only) children.
-                children_lists.append(
-                    [child for child in seg.segments if not child.is_meta]
-                )
-            # Always check against the full set of children.
-            children_lists.append(seg.segments)
-            children: List[BaseSegment]
-            for children in children_lists:
-                if edit_type == "create_before" and children[0] is child:
-                    anchor = seg
-                    assert anchor.raw.startswith(segment.raw)
-                    child = seg
-                    break
-                elif edit_type == "create_after" and children[-1] is child:
-                    anchor = seg
-                    assert anchor.raw.endswith(segment.raw)
-                    child = seg
-                    break
+        if (
+            context.parent_stack[0]
+            and context.parent_stack[0].path_to(segment)
+            and context.parent_stack[0].path_to(segment)[1:-1]
+        ):
+            for seg in context.parent_stack[0].path_to(segment)[1:-1][::-1]:
+                # Which lists of children to check against.
+                children_lists: List[List[BaseSegment]] = []
+                if filter_meta:
+                    # Optionally check against filtered (non-meta only) children.
+                    children_lists.append(
+                        [child for child in seg.segments if not child.is_meta]
+                    )
+                # Always check against the full set of children.
+                children_lists.append(seg.segments)
+                children: List[BaseSegment]
+                for children in children_lists:
+                    if edit_type == "create_before" and children[0] is child:
+                        anchor = seg
+                        assert anchor.raw.startswith(segment.raw)
+                        child = seg
+                        break
+                    elif edit_type == "create_after" and children[-1] is child:
+                        anchor = seg
+                        assert anchor.raw.endswith(segment.raw)
+                        child = seg
+                        break
         return anchor
 
     @staticmethod

src/sqlfluff/rules/L026.py

@@ -148,7 +148,8 @@ def _should_ignore_reference(reference, selectable):
         # - They are the target table, similar to an INSERT or UPDATE
         #   statement, thus not expected to match a table in the FROM
         #   clause.
-        return any(seg.is_type("into_table_clause") for seg in ref_path)
+        if ref_path:
+            return any(seg.is_type("into_table_clause") for seg in ref_path)
 
     @staticmethod
     def _get_table_refs(ref, dialect):