Add support for no button to StatefulBrowser.submit_selected

mechanicalsoup/form.py

@@ -309,7 +309,8 @@ def choose_submit(self, submit):
         :param submit: The :class:`bs4.element.Tag` (or just its
             *name*-attribute) that identifies the submit element to use. If
             ``None``, will choose the first valid submit element in the form,
-            if one exists.
+            if one exists. If ``False``, will not use any submit element;
+            this is useful for simulating AJAX requests, for example.
 
         To simulate a normal web browser, only one submit element must be
         sent. Therefore, this does not need to be called if there is only
@@ -362,7 +363,7 @@ def choose_submit(self, submit):
                 # omitted from the submitted form data.
                 del inp['name']
 
-        if not found and submit is not None:
+        if not found and submit is not None and submit is not False:
             raise LinkNotFoundError(
                 f"Specified submit element not found: {submit}"
             )

tests/test_stateful_browser.py

@@ -170,6 +170,31 @@ def test_submit_btnName(expected_post):
     assert initial_state != browser._StatefulBrowser__state
 
 
+@pytest.mark.parametrize("expected_post", [
+    pytest.param(
+        [
+            ('text', 'Setting some text!'),
+            ('comment', 'Selecting an input submit'),
+        ], id='input'),
+    pytest.param(
+        [
+            ('text', '= Heading =\n\nNew page here!\n'),
+            ('comment', 'Selecting a button submit'),
+        ], id='button'),
+])
+def test_submit_no_btn(expected_post):
+    '''Tests that no submit inputs are posted when btnName=False.'''
+    browser, url = setup_mock_browser(expected_post=expected_post)
+    browser.open(url)
+    browser.select_form('#choose-submit-form')
+    browser['text'] = dict(expected_post)['text']
+    browser['comment'] = dict(expected_post)['comment']
+    initial_state = browser._StatefulBrowser__state
+    res = browser.submit_selected(btnName=False)
+    assert res.status_code == 200 and res.text == 'Success!'
+    assert initial_state != browser._StatefulBrowser__state
+
+
 def test_submit_dont_modify_kwargs():
     """Test that submit_selected() doesn't modify the caller's passed-in
     kwargs, for example when adding a Referer header.