Deal a lot better with prefixes in range extractions

jedi/api/refactoring.py

@@ -233,7 +233,7 @@ def extract_variable(grammar, path, module_node, name, pos, until_pos):
         raise RefactoringError(message)
 
     generated_code = name + ' = ' + _expression_nodes_to_string(nodes)
-    file_to_node_changes = {path: _replace(nodes, name, generated_code)}
+    file_to_node_changes = {path: _replace(nodes, name, generated_code, pos)}
     return Refactoring(grammar, file_to_node_changes)
 
 
@@ -294,19 +294,22 @@ def _find_nodes(module_node, pos, until_pos):
     return nodes
 
 
-def _replace(nodes, expression_replacement, extracted, insert_before_leaf=None):
+def _replace(nodes, expression_replacement, extracted, pos, insert_before_leaf=None):
     # Now try to replace the nodes found with a variable and move the code
     # before the current statement.
     definition = _get_parent_definition(nodes[0])
     if insert_before_leaf is None:
         insert_before_leaf = definition.get_first_leaf()
+    first_node_leaf = nodes[0].get_first_leaf()
+
+    lines = split_lines(insert_before_leaf.prefix, keepends=True)
+    if first_node_leaf is insert_before_leaf:
+        removed_line_count = nodes[0].start_pos[0] - pos[0]
+        lines = lines[:-removed_line_count - 1] + [lines[-1]]
+    lines[-1:-1] = [indent_block(extracted, lines[-1]) + '\n']
+    extracted_prefix = ''.join(lines)
 
     replacement_dct = {}
-    extracted_prefix = _insert_line_before(
-        insert_before_leaf.prefix,
-        extracted,
-    )
-    first_node_leaf = nodes[0].get_first_leaf()
     if first_node_leaf is insert_before_leaf:
         replacement_dct[nodes[0]] = extracted_prefix + expression_replacement
     else:
@@ -322,6 +325,14 @@ def _expression_nodes_to_string(nodes):
     return ''.join(n.get_code(include_prefix=i != 0) for i, n in enumerate(nodes))
 
 
+def _suite_nodes_to_string(nodes, pos):
+    n = nodes[0]
+    included_line_count = n.start_pos[0] - pos[0]
+    lines = split_lines(n.get_first_leaf().prefix, keepends=True)[-included_line_count - 1]
+    return ''.join(lines) + n.get_code(include_prefix=False) \
+        + ''.join(n.get_code() for n in nodes[1:])
+
+
 def _remove_indent_of_prefix(prefix):
     r"""
     Removes the last indentation of a prefix, e.g. " \n \n " becomes " \n \n".
@@ -333,12 +344,6 @@ def _get_indentation(node):
     return split_lines(node.get_first_leaf().prefix)[-1]
 
 
-def _insert_line_before(prefix, code):
-    lines = split_lines(prefix, keepends=True)
-    lines[-1:-1] = [indent_block(code, lines[-1]) + '\n']
-    return ''.join(lines)
-
-
 def _get_parent_definition(node):
     """
     Returns the statement where a node is defined.
@@ -398,7 +403,6 @@ def extract_function(inference_state, path, module_context, name, pos, until_pos
     is_bound_method = context.is_bound_method()
     params, return_variables = list(_find_inputs_and_outputs(context, nodes))
 
-    dct = {}
     # Find variables
     # Is a class method / method
     if context.is_module():
@@ -420,7 +424,7 @@ def extract_function(inference_state, path, module_context, name, pos, until_pos
         )) or [return_variables[-1]]
 
         output_var_str = ', '.join(return_variables)
-        code_block = dedent(''.join(n.get_code() for n in nodes))
+        code_block = dedent(_suite_nodes_to_string(nodes, pos))
         code_block += 'return ' + output_var_str + '\n'
 
     decorator = ''
@@ -453,10 +457,8 @@ def extract_function(inference_state, path, module_context, name, pos, until_pos
     else:
         replacement = _get_indentation(nodes[0]) + output_var_str + ' = ' + function_call
 
-    dct[nodes[0]] = replacement
-    for node in nodes[1:]:
-        dct[node] = ''
-    file_to_node_changes = {path: _replace(nodes, replacement, function_code, insert_before_leaf)}
+    replaced_str = _replace(nodes, replacement, function_code, pos, insert_before_leaf)
+    file_to_node_changes = {path: replaced_str}
     return Refactoring(inference_state.grammar, file_to_node_changes)
 
 

test/refactor/extract_function.py

@@ -159,6 +159,7 @@ def x(z):
 v1 = 3
 v2 = 2
 x = test(v1 + v2 * v3)
+
 # ++++++++++++++++++++++++++++++++++++++++++++++++++
 #? 0 text {'new_name': 'a', 'until_line': 4}
 def a(test, v3):
@@ -168,4 +169,25 @@ def a(test, v3):
     return x
 
 
-a(test, v3)
+x = a(test, v3)
+# -------------------------------------------------- with-range-2
+#? 2 text {'new_name': 'a', 'until_line': 6, 'until_column': 4}
+#foo
+v1 = 3
+v2 = 2
+x, y = test(v1 + v2 * v3)
+#raaaa
+y
+# ++++++++++++++++++++++++++++++++++++++++++++++++++
+#? 2 text {'new_name': 'a', 'until_line': 6, 'until_column': 4}
+def a(test, v3):
+    #foo
+    v1 = 3
+    v2 = 2
+    x, y = test(v1 + v2 * v3)
+    #raaaa
+    return y
+
+
+y = a(test, v3)
+y