Fix inconsistency in indent adjustment behavior when completing

There is a small inconsistency when we're dealing with a text edit and the text
edit is not a snippet. In that case, if the new text of the completion
contained newlines, the subsequent line would not be "auto-indented". Whereas
with the three other possible cases, it would be auto-indented. That is because
the other three cases use the "insert" and "insert_snippet" commands, whereas
with this special case we were using the view.insert method.

plugin/completion.py

@@ -9,6 +9,7 @@
 from .core.views import range_to_region
 from .core.views import show_lsp_popup
 from .core.views import update_lsp_popup
+import functools
 
 SessionName = str
 
@@ -72,49 +73,29 @@ def run(self, edit: sublime.Edit, item: CompletionItem, session_name: str) -> No
         if text_edit:
             new_text = text_edit["newText"].replace("\r", "")
             edit_region = range_to_region(Range.from_lsp(text_edit['range']), self.view)
-            if item.get("insertTextFormat", InsertTextFormat.PlainText) == InsertTextFormat.Snippet:
-                for region in self.translated_regions(edit_region):
-                    self.view.erase(edit, region)
-                self.view.run_command("insert_snippet", {"contents": new_text})
-            else:
-                for region in self.translated_regions(edit_region):
-                    # NOTE: Cannot do .replace, because ST will select the replacement.
-                    self.view.erase(edit, region)
-                    self.view.insert(edit, region.a, new_text)
+            for region in self._translated_regions(edit_region):
+                self.view.erase(edit, region)
         else:
-            insert_text = item.get("insertText") or item["label"]
-            insert_text = insert_text.replace("\r", "")
-            if item.get("insertTextFormat", InsertTextFormat.PlainText) == InsertTextFormat.Snippet:
-                self.view.run_command("insert_snippet", {"contents": insert_text})
-            else:
-                self.view.run_command("insert", {"characters": insert_text})
-        self.epilogue(item, session_name)
-
-    def translated_regions(self, edit_region: sublime.Region) -> Generator[sublime.Region, None, None]:
-        selection = self.view.sel()
-        primary_cursor_position = selection[0].b
-        for region in reversed(selection):
-            # For each selection region, apply the same removal as for the "primary" region.
-            # To do that, translate, or offset, the LSP edit region into the non-"primary" regions.
-            # The concept of "primary" is our own, and there is no mention of it in the LSP spec.
-            translation = region.b - primary_cursor_position
-            translated_edit_region = sublime.Region(edit_region.a + translation, edit_region.b + translation)
-            yield translated_edit_region
-
-    def epilogue(self, item: CompletionItem, session_name: str) -> None:
+            new_text = item.get("insertText") or item["label"]
+            new_text = new_text.replace("\r", "")
+        if item.get("insertTextFormat", InsertTextFormat.PlainText) == InsertTextFormat.Snippet:
+            self.view.run_command("insert_snippet", {"contents": new_text})
+        else:
+            self.view.run_command("insert", {"characters": new_text})
+        # todo: this should all run from the worker thread
         session = self.session_by_name(session_name, 'completionProvider.resolveProvider')
-
-        def resolve_on_main_thread(item: CompletionItem, session_name: str) -> None:
-            sublime.set_timeout(lambda: self.on_resolved(item, session_name))
-
         additional_text_edits = item.get('additionalTextEdits')
         if session and not additional_text_edits:
-            request = Request.resolveCompletionItem(item, self.view)
-            session.send_request_async(request, lambda response: resolve_on_main_thread(response, session_name))
+            session.send_request_async(
+                Request.resolveCompletionItem(item, self.view),
+                functools.partial(self._on_resolved_async, session_name))
         else:
-            self.on_resolved(item, session_name)
+            self._on_resolved(session_name, item)
 
-    def on_resolved(self, item: CompletionItem, session_name: str) -> None:
+    def _on_resolved_async(self, session_name: str, item: CompletionItem) -> None:
+        sublime.set_timeout(functools.partial(self._on_resolved, session_name, item))
+
+    def _on_resolved(self, session_name: str, item: CompletionItem) -> None:
         additional_edits = item.get('additionalTextEdits')
         if additional_edits:
             edits = [parse_text_edit(additional_edit) for additional_edit in additional_edits]
@@ -128,3 +109,14 @@ def on_resolved(self, item: CompletionItem, session_name: str) -> None:
                 "session_name": session_name
             }
             self.view.run_command("lsp_execute", args)
+
+    def _translated_regions(self, edit_region: sublime.Region) -> Generator[sublime.Region, None, None]:
+        selection = self.view.sel()
+        primary_cursor_position = selection[0].b
+        for region in reversed(selection):
+            # For each selection region, apply the same removal as for the "primary" region.
+            # To do that, translate, or offset, the LSP edit region into the non-"primary" regions.
+            # The concept of "primary" is our own, and there is no mention of it in the LSP spec.
+            translation = region.b - primary_cursor_position
+            translated_edit_region = sublime.Region(edit_region.a + translation, edit_region.b + translation)
+            yield translated_edit_region

tests/test_completion.py

@@ -2,6 +2,7 @@
 from LSP.plugin.core.protocol import CompletionItem
 from LSP.plugin.core.protocol import CompletionItemLabelDetails
 from LSP.plugin.core.protocol import CompletionItemTag
+from LSP.plugin.core.protocol import InsertTextFormat
 from LSP.plugin.core.typing import Any, Generator, List, Dict, Callable, Optional
 from LSP.plugin.core.views import format_completion
 from setup import TextDocumentTestCase
@@ -212,7 +213,7 @@ def test_space_added_in_label(self) -> 'Generator':
                         }
                     }
                 },
-                "insertTextFormat": 2,
+                "insertTextFormat": InsertTextFormat.Snippet,
                 "insertText": "const",
                 "filterText": "const",
                 "score": 6
@@ -244,7 +245,7 @@ def test_dash_missing_from_label(self) -> 'Generator':
                 "additionalTextEdits": None,
                 "data": None,
                 "range": None,
-                "insertTextFormat": 1,
+                "insertTextFormat": InsertTextFormat.PlainText,
                 "sortText": "0001UniqueId",
                 "kind": 6,
                 "detail": "[string[]]"
@@ -309,7 +310,7 @@ def test_edit_after_nonword(self) -> 'Generator':
                 "label": "apply[A](xs: A*): List[A]",
                 "sortText": "00000",
                 "preselect": True,
-                "insertTextFormat": 2,
+                "insertTextFormat": InsertTextFormat.Snippet,
                 "filterText": "apply",
                 "data": {
                     "symbol": "scala/collection/immutable/List.apply().",
@@ -342,7 +343,7 @@ def test_filter_text_is_not_a_prefix_of_label(self) -> 'Generator':
                 "kind": 12,
                 "sortText": "00002",
                 "filterText": "e",
-                "insertTextFormat": 2,
+                "insertTextFormat": InsertTextFormat.Snippet,
                 "textEdit": {
                     "range": {
                         "start": {"line": 0, "character": 0},
@@ -588,6 +589,22 @@ def test_nontrivial_text_edit_removal_with_buffer_modifications_json(self) -> 'G
         yield self.create_commit_completion_closure()
         self.assertEqual(self.read_file(), '{"keys": []}')
 
+    def test_text_edit_plaintext_with_multiple_lines_indented(self) -> Generator[None, None, None]:
+        self.type("\t\n\t")
+        self.move_cursor(1, 2)
+        self.set_response("textDocument/completion", [{
+            'label': 'a',
+            'textEdit': {
+                'range': {'start': {'line': 1, 'character': 4}, 'end': {'line': 1, 'character': 4}},
+                'newText': 'a\n\tb'
+            },
+            'insertTextFormat': InsertTextFormat.PlainText
+        }])
+        yield from self.select_completion()
+        yield from self.await_message("textDocument/completion")
+        # the "b" should be intended one level deeper
+        self.assertEqual(self.read_file(), '\t\n\ta\n\t\tb')
+
     def test_show_deprecated_flag(self) -> None:
         item_with_deprecated_flag = {
             "label": 'hello',