Completion detail using module name, function parameters (#170)

* Use "builtin" or parent path for completion detail

* Append parameters to completion item label if function/method

* Update tests to expect labels with parentheses and args

* Update test_completion.py

* Check completion label specifically for python 2 or 3

* Use list comprehension instead of map for parameter list

pyls/plugins/completion.py

@@ -10,14 +10,27 @@
 def pyls_completions(document, position):
     definitions = document.jedi_script(position).completions()
     return [{
-        'label': d.name,
+        'label': _label(d),
         'kind': _kind(d),
-        'detail': d.description or "",
+        'detail': _detail(d),
         'documentation': d.docstring(),
-        'sortText': _sort_text(d)
+        'sortText': _sort_text(d),
+        'insertText': d.name
     } for d in definitions]
 
 
+def _label(definition):
+    if definition.type in ('function', 'method'):
+        params = ", ".join(param.name for param in definition.params)
+        return "{}({})".format(definition.name, params)
+
+    return definition.name
+
+
+def _detail(definition):
+    return "builtin" if definition.in_builtin_module() else definition.parent().full_name or ""
+
+
 def _sort_text(definition):
     """ Ensure builtins appear at the bottom.
     Description is of format <type>: <module>.<item>

test/plugins/test_completion.py

@@ -1,4 +1,5 @@
 # Copyright 2017 Palantir Technologies, Inc.
+import sys
 from pyls import uris
 from pyls.plugins.completion import pyls_completions
 from pyls.workspace import Document
@@ -23,7 +24,10 @@ def test_completion():
     items = pyls_completions(doc, com_position)
 
     assert len(items) > 0
-    assert items[0]['label'] == 'read'
+    if (sys.version_info > (3, 0)):
+        assert items[0]['label'] == 'read(args)'
+    else:
+        assert items[0]['label'] == 'read()'
 
 
 def test_completion_ordering():
@@ -35,6 +39,6 @@ def test_completion_ordering():
     items = {c['label']: c['sortText'] for c in completions}
 
     # Assert that builtins come after our own functions even if alphabetically they're before
-    assert items['hello'] < items['dict']
+    assert items['hello()'] < items['dict']
     # And that 'hidden' functions come after unhidden ones
-    assert items['hello'] < items['_a_hello']
+    assert items['hello()'] < items['_a_hello()']