Add options support to yapf

Author: masad-frost

pylsp/plugins/yapf_format.py

@@ -46,13 +46,50 @@ def _format(document, lines=None, options=None):
         replace_cr = True
         source = source.replace('\r', '\n')
 
+    # Get the default styles as a string
+    # for a preset configuration, i.e. "pep8"
+    style_config = file_resources.GetDefaultStyleForDir(
+        os.path.dirname(document.path)
+    )
+    if options is not None:
+        # We have options passed from LSP format request
+        # let's pass them to the formatter.
+        # First we want to get a dictionary of the preset style
+        # to pass instead of a string so that we can modify it
+        style_config = style.CreateStyleFromConfig(style_config)
+
+        use_tabs = style_config['USE_TABS']
+        indent_width = style_config['INDENT_WIDTH']
+
+        if options.get('tabSize') is not None:
+            indent_width = max(int(options.get('tabSize')), 1)
+
+        if options.get('insertSpaces') is not None:
+            # TODO is it guaranteed to be a boolean, or can it be a string?
+            use_tabs = not options.get('insertSpaces')
+
+            if use_tabs:
+                # Indent width doesn't make sense when using tabs
+                # the specifications state: "Size of a tab in spaces"
+                indent_width = 1
+
+        style_config['USE_TABS'] = use_tabs
+        style_config['INDENT_WIDTH'] = indent_width
+        style_config['CONTINUATION_INDENT_WIDTH'] = indent_width
+
+        for style_option, value in options.items():
+            # Apply arbitrary options passed as formatter options
+            if style_option not in style_config:
+                # ignore if it's not a known yapf config
+                continue
+
+            style_config[style_option] = value
+
     new_source, changed = FormatCode(
         source,
         lines=lines,
         filename=document.filename,
-        style_config=file_resources.GetDefaultStyleForDir(
-            os.path.dirname(document.path)
-        )
+        style_config=style_config
     )
 
     if not changed:

test/plugins/test_yapf_format.py

@@ -65,3 +65,30 @@ def test_cr_line_endings(workspace):
     res = pylsp_format_document(doc)
 
     assert res[0]['newText'] == 'import os\rimport sys\r\rdict(a=1)\r'
+
+FOUR_SPACE_DOC = """def hello():
+    pass
+"""
+
+def test_format_with_tab_size_option(workspace):
+    doc = Document(DOC_URI, workspace, FOUR_SPACE_DOC)
+    res = pyls_format_document(doc, { "tabSize": "8" })
+
+    assert len(res) == 1
+    assert res[0]['newText'] == FOUR_SPACE_DOC.replace("    ", "        ")
+
+
+def test_format_with_insert_spaces_option(workspace):
+    doc = Document(DOC_URI, workspace, FOUR_SPACE_DOC)
+    res = pyls_format_document(doc, { "insertSpaces": False })
+
+    assert len(res) == 1
+    assert res[0]['newText'] == FOUR_SPACE_DOC.replace("    ", "\t")
+
+
+def test_format_with_yapf_specific_option(workspace):
+    doc = Document(DOC_URI, workspace, FOUR_SPACE_DOC)
+    res = pyls_format_document(doc, { "USE_TABS": True })
+
+    assert len(res) == 1
+    assert res[0]['newText'] == FOUR_SPACE_DOC.replace("    ", "\t")