Add support of selection of async statements

autoload/braceless.vim

@@ -11,7 +11,7 @@ let s:pattern_cache = {}
 " Default patterns
 let s:pattern_default = {}
 let s:pattern_default.python = {
-      \   'start': '\<\%(if\|def\|for\|try\|elif\|else\|with\|class\|while\|except\|finally\)\>\_.\{-}:\ze\s*\%(\_$\|#\)',
+      \   'start': '\<\%(if\|async\|def\|for\|try\|elif\|else\|with\|class\|while\|except\|finally\)\>\_.\{-}:\ze\s*\%(\_$\|#\)',
       \   'decorator': '\_^\s*@\%(\k\|\.\)\+\%((\_.\{-})\)\?\_$',
       \   'end': '\S',
       \}

test/selection.vader

@@ -440,3 +440,33 @@ Expect python (innermost function replaced):
   def example():
       x
       return example
+
+
+Given python (async function):
+==========================================
+  async def example():
+      async with foo:
+          a
+          b
+          c
+      return 42
+
+Do (replace inner block):
+================================
+  3GciPx
+
+Expect python (innermost function replaced):
+============================================
+  async def example():
+      async with foo:
+          x
+      return 42
+
+Do (replace inner block):
+================================
+  ciPx
+
+Expect python (innermost function replaced):
+============================================
+  async def example():
+      x