Don't squish all the args to the RHS

It looks bad when they're all aligned over to the right when there's all
this whitespace being wasted.

CHANGELOG

@@ -16,6 +16,8 @@
 - Ensure splitting of arguments if there's a named assign present.
 - Prefer to coalesce opening brackets if it's not at the beginning of a
   function call.
+- Prefer not to squish all of the elements in a function call over to the
+  right-hand side. Split the arguments instead.
 
 ## [0.16.0] 2017-02-05
 ### Added

yapf/yapflib/format_decision_state.py

@@ -323,6 +323,10 @@ def MustSplit(self):
           # line and it's not a function call.
           if self._FitsOnLine(previous, previous.matching_bracket):
             return False
+        elif not self._FitsOnLine(previous, previous.matching_bracket):
+          if (self.column_limit - self.column) / float(self.column_limit) < 0.3:
+            # Try not to squish all of the arguments off to the right.
+            return True
       else:
         # Split after the opening of a container if it doesn't fit on the
         # current line or if it has a comment.

yapftests/reformatter_basic_test.py

@@ -1573,6 +1573,33 @@ def method(self):
     finally:
       style.SetGlobalStyle(style.CreateChromiumStyle())
 
+  def testStableInlinedDictionaryFormatting(self):
+    try:
+      style.SetGlobalStyle(style.CreatePEP8Style())
+      unformatted_code = textwrap.dedent("""\
+          def _():
+              url = "http://{0}/axis-cgi/admin/param.cgi?{1}".format(
+                  value, urllib.urlencode({'action': 'update', 'parameter': value}))
+          """)
+      expected_formatted_code = textwrap.dedent("""\
+          def _():
+              url = "http://{0}/axis-cgi/admin/param.cgi?{1}".format(
+                  value, urllib.urlencode({
+                      'action': 'update',
+                      'parameter': value
+                  }))
+          """)
+
+      uwlines = yapf_test_helper.ParseAndUnwrap(unformatted_code)
+      reformatted_code = reformatter.Reformat(uwlines)
+      self.assertCodeEqual(expected_formatted_code, reformatted_code)
+
+      uwlines = yapf_test_helper.ParseAndUnwrap(reformatted_code)
+      reformatted_code = reformatter.Reformat(uwlines)
+      self.assertCodeEqual(expected_formatted_code, reformatted_code)
+    finally:
+      style.SetGlobalStyle(style.CreateChromiumStyle())
+
   def testDontSplitKeywordValueArguments(self):
     unformatted_code = textwrap.dedent("""\
         def mark_game_scored(gid):