add method get_comments_on_answers to class Site

TODO.md

@@ -19,10 +19,10 @@
    + [X] `get_posts(self, ids: list[int] | None = None, **kwargs: Any) -> list[Item]` - API method `posts/` and `posts/{ids}`;
    + [X] `get_post(self, c_id: int, **kwargs: Any) -> Item | None`;
    + [X] `get_suggested_edits(self, ids: list[int] | None = None, **kwargs: Any) -> list[Item]` - API method `suggested-edits/` and `suggested-edits/{ids}`;
-   + [ ] `get_comments_on_answers(self, ids: list[int] | None = None, **kwargs: Any) -> list[Item]` - API method `answers/{ids}/comments`;
-   + [ ] `get_comments_on_articles(self, ids: list[int] | None = None, **kwargs: Any) -> list[Item]` - API method `articles/{ids}/comments`;
-   + [ ] `get_comments_on_posts(self, ids: list[int] | None = None, **kwargs: Any) -> list[Item]` - API method `posts/{ids}/comments`;
-   + [ ] `get_comments_on_questions(self, ids: list[int] | None = None, **kwargs: Any) -> list[Item]` - API method `questions/{ids}/comments`;
+   + [X] `get_comments_on_answers(self, ids: list[int], **kwargs: Any) -> list[Item]` - API method `answers/{ids}/comments`;
+   + [ ] `get_comments_on_articles(self, ids: list[int], **kwargs: Any) -> list[Item]` - API method `articles/{ids}/comments`;
+   + [ ] `get_comments_on_posts(self, ids: list[int], **kwargs: Any) -> list[Item]` - API method `posts/{ids}/comments`;
+   + [ ] `get_comments_on_questions(self, ids: list[int], **kwargs: Any) -> list[Item]` - API method `questions/{ids}/comments`;
    + [X] `get_non_tag_based_badges(self, **kwargs: Any) -> list[Item]` - API method `badges/name`;
  + [X] `IndexError` raises in methods `Site.get_<singular>`, when there is no items in response;
  + [X] add constant `API_VERSION` to file `tests/test_client/__init__.py` and usage of it to tests.

src/pystackapi/site.py

@@ -142,6 +142,13 @@ def get_comment(self, c_id: int, **kwargs: Any) -> Item | None:
         except IndexError:
             return None
 
+    def get_comments_on_answers(self, ids: list[int], **kwargs: Any) -> list[Item]:
+        """Returns the comments on a set of answers."""
+        if not ids:
+            raise BadArgumentsError('the `ids` argument should be a non empty list.')
+        return [Item(data) for data in
+                self.get(f'answers/{";".join(map(str, ids))}/comments/', **kwargs)['items']]
+
     def get_info(self) -> Item:
         """Returns a collection of statistics about the site."""
         return Item(self.get('info/')['items'][0])  # here can't be `IndexError`

tests/test_client/test_get_comments.py

@@ -1,4 +1,4 @@
-"""Tests for `Site.get_comments` and `Site.get_comment`."""
+"""Tests for `Site.get_comments`, `Site.get_comment` and `Site.get_comments_on_*`."""
 import lest
 
 from pystackapi import site as site_m
@@ -64,3 +64,21 @@ def test_get_comment_with_no_data() -> None:
     lest.assert_true(res is None)
 
     requests.no_data = []
+
+
+# ---- tests for `Site.get_comments_on_answers` ---
+
+
+@lest.register
+def test_get_comments_on_answers_url() -> None:
+    site.get_comments_on_answers([1, 2])
+
+    lest.assert_eq(requests.url, f'https://api.stackexchange.com/{API_VERSION}/answers/1;2/'
+                                 f'comments/?site=stackoverflow')
+
+
+@lest.register
+def test_get_comments_on_answers_return_value() -> None:
+    res = site.get_comments_on_answers([1, 2])
+
+    lest.assert_eq(res, [Item({'id': 1})])