Copied the experiments implementation to the macros file

Is more robust

kiplot/macros.py

@@ -1,4 +1,5 @@
-from ast import *
+from ast import (Assign, Name, Attribute, Expr, Num, Str, NameConstant, Load, Store)
+
 
 def document(sentences, to_source, **kw):
     """ This macro takes literal strings and converts them into:
@@ -7,41 +8,47 @@ def document(sentences, to_source, **kw):
         ID is the first target of the last assignment.
         type_hint is the assigned type and default value (only works for a few types)
         STRING is the literal string """
-    cur_attr = None
-    cur_value = None
     for n in range(len(sentences)):
         s = sentences[n]
-        if isinstance(s, Assign):
-            cur_target = s.targets[0]
-            if isinstance(cur_target, Name):
-                cur_attr = cur_target.id
+        if not n:
+            prev = s
+            continue
+        # The whole sentence is a string?
+        if (isinstance(s, Expr) and isinstance(s.value, Str) and
+           # and the previous is an assign
+           isinstance(prev, Assign)):  # noqa: E128
+            # Apply it to the first target
+            target = prev.targets[0]
+            value = prev.value
+            # Extract its name
+            # variables and attributes are supported
+            if isinstance(target, Name):
+                name = target.id
                 is_attr = False
-            elif isinstance(cur_target, Attribute):
-                cur_attr = cur_target.attr
+            elif isinstance(target, Attribute):
+                name = target.attr
                 is_attr = True
             else:
-                raise TypeError
-            cur_value = s.value
-        elif cur_attr and isinstance(s, Expr):
-            if isinstance(s.value, Str):
-                # Remove starting underscore
-                if cur_attr[0] == '_':
-                    cur_attr = cur_attr[1:]
-                # Create a _help_ID
-                doc_id = '_help_'+cur_attr
-                # Create the type hint for numbers, strings and booleans
-                type_hint = ''
-                if isinstance(cur_value, Num):
-                    type_hint = '[number={}]'.format(cur_value.n)
-                elif isinstance(cur_value, Str):
-                    type_hint = "[string='{}']".format(cur_value.s)
-                elif isinstance(cur_value, NameConstant) and isinstance(cur_value.value, bool):
-                    type_hint = '[boolean={}]'.format(str(cur_value.value).lower())
-                # Transform the string into an assign for _help_ID
-                if is_attr:
-                    cur_target = Attribute(value=Name(id='self', ctx=Load()), attr=doc_id, ctx=Store())
-                else:
-                    cur_target = Name(id=doc_id, ctx=Store())
-                sentences[n] = Assign(targets=[cur_target], value=Str(s=type_hint+s.value.s))
+                continue
+            # Remove starting underscore
+            if name[0] == '_':
+                name = name[1:]
+            # Create a _help_ID
+            doc_id = '_help_'+name
+            # Create the type hint for numbers, strings and booleans
+            type_hint = ''
+            if isinstance(value, Num):
+                type_hint = '[number={}]'.format(value.n)
+            elif isinstance(value, Str):
+                type_hint = "[string='{}']".format(value.s)
+            elif isinstance(value, NameConstant) and isinstance(value.value, bool):
+                type_hint = '[boolean={}]'.format(str(value.value).lower())
+            # Transform the string into an assign for _help_ID
+            if is_attr:
+                target = Attribute(value=Name(id='self', ctx=Load()), attr=doc_id, ctx=Store())
+            else:
+                target = Name(id=doc_id, ctx=Store())
+            sentences[n] = Assign(targets=[target], value=Str(s=type_hint+s.value.s))
+        prev = s
     # Return the modified AST
     return sentences