Add orelse_lineno and orelse_col_offset to nodes.If

ChangeLog

@@ -6,7 +6,7 @@ What's New in astroid 2.12.0?
 =============================
 Release date: TBA
 
-
+* Add ``orelse_lineno`` and ``orelse_col_offset`` attributes to ``nodes.If``.
 
 What's New in astroid 2.11.1?
 =============================

astroid/nodes/node_classes.py

@@ -3034,6 +3034,12 @@ def __init__(
         self.is_orelse: bool = False
         """Whether the if-statement is the orelse-block of another if statement."""
 
+        self.orelse_lineno: Optional[int] = None
+        """The line number of the ``else`` or ``elif`` keyword."""
+
+        self.orelse_col_offset: Optional[int] = None
+        """The column offset of the ``else`` or ``elif`` keyword."""
+
         super().__init__(
             lineno=lineno,
             col_offset=col_offset,
@@ -3047,6 +3053,9 @@ def postinit(
         test: Optional[NodeNG] = None,
         body: Optional[typing.List[NodeNG]] = None,
         orelse: Optional[typing.List[NodeNG]] = None,
+        *,
+        orelse_lineno: Optional[int] = None,
+        orelse_col_offset: Optional[int] = None,
     ) -> None:
         """Do some setup after initialisation.
 
@@ -3055,6 +3064,10 @@ def postinit(
         :param body: The contents of the block.
 
         :param orelse: The contents of the ``else`` block.
+
+        :param orelse_lineno: The line number of the ``else`` or ``elif`` keyword.
+
+        :param orelse_lineno: The column offset of the ``else`` or ``elif`` keyword.
         """
         self.test = test
         if body is not None:
@@ -3063,6 +3076,8 @@ def postinit(
             self.orelse = orelse
         if isinstance(self.parent, If) and self in self.parent.orelse:
             self.is_orelse = True
+        self.orelse_lineno = orelse_lineno
+        self.orelse_col_offset = orelse_col_offset
 
     @cached_property
     def blockstart_tolineno(self):

astroid/rebuilder.py

@@ -1382,6 +1382,33 @@ def visit_global(self, node: "ast.Global", parent: NodeNG) -> nodes.Global:
                 self._global_names[-1].setdefault(name, []).append(newnode)
         return newnode
 
+    def _find_orelse_keyword(
+        self, node: "ast.If"
+    ) -> Tuple[Optional[int], Optional[int]]:
+        """Get the line number and column offset of the `else` or `elif` keyword."""
+        if not self._data or not node.orelse:
+            return None, None
+
+        end_lineno = node.orelse[0].lineno
+
+        def find_keyword(begin: int, end: int) -> Tuple[Optional[int], Optional[int]]:
+            # pylint: disable-next=unsubscriptable-object
+            data = "\n".join(self._data[begin:end])
+
+            try:
+                tokens = list(generate_tokens(StringIO(data).readline))
+            except tokenize.TokenError:
+                # If we cut-off in the middle of multi-line if statements we
+                # generate a TokenError here. We just keep trying
+                # until the multi-line statement is closed.
+                return find_keyword(begin, end + 1)
+            for t in tokens[::-1]:
+                if t.type == token.NAME and t.string in {"else", "elif"}:
+                    return node.lineno + t.start[0] - 1, t.start[1]
+            raise AssertionError()  # pragma: no cover # Shouldn't be reached.
+
+        return find_keyword(node.lineno - 1, end_lineno)
+
     def visit_if(self, node: "ast.If", parent: NodeNG) -> nodes.If:
         """visit an If node by returning a fresh instance of it"""
         newnode = nodes.If(
@@ -1392,10 +1419,15 @@ def visit_if(self, node: "ast.If", parent: NodeNG) -> nodes.If:
             end_col_offset=getattr(node, "end_col_offset", None),
             parent=parent,
         )
+
+        orelse_lineno, orelse_col_offset = self._find_orelse_keyword(node)
+
         newnode.postinit(
             self.visit(node.test, newnode),
             [self.visit(child, newnode) for child in node.body],
             [self.visit(child, newnode) for child in node.orelse],
+            orelse_lineno=orelse_lineno,
+            orelse_col_offset=orelse_col_offset,
         )
         return newnode
 

tests/unittest_nodes.py

@@ -343,6 +343,21 @@ def test_block_range(self) -> None:
         self.assertEqual(self.astroid.body[1].orelse[0].block_range(7), (7, 8))
         self.assertEqual(self.astroid.body[1].orelse[0].block_range(8), (8, 8))
 
+    def test_orelse_line_numbering(self) -> None:
+        """Test the position info for the `else` keyword."""
+        assert self.astroid.body[0].orelse_lineno is None
+        assert self.astroid.body[0].orelse_col_offset is None
+        assert self.astroid.body[1].orelse_lineno == 7
+        assert self.astroid.body[1].orelse_col_offset == 0
+        assert self.astroid.body[2].orelse_lineno == 12
+        assert self.astroid.body[2].orelse_col_offset == 0
+        assert self.astroid.body[3].orelse_lineno == 17
+        assert self.astroid.body[3].orelse_col_offset == 0
+        assert self.astroid.body[3].orelse[0].orelse_lineno == 19
+        assert self.astroid.body[3].orelse[0].orelse_col_offset == 0
+        assert self.astroid.body[3].orelse[0].orelse[0].orelse_lineno == 21
+        assert self.astroid.body[3].orelse[0].orelse[0].orelse_col_offset == 0
+
     @staticmethod
     @pytest.mark.filterwarnings("ignore:.*is_sys_guard:DeprecationWarning")
     def test_if_sys_guard() -> None: