PY-20744 Python formatter is aware of variable annotations

python/src/com/jetbrains/python/formatter/PythonFormattingModelBuilder.java

@@ -95,6 +95,8 @@ public class PythonFormattingModelBuilder implements FormattingModelBuilderEx, C
       .betweenInside(MINUS, GT, ANNOTATION).none()
       .beforeInside(ANNOTATION, FUNCTION_DECLARATION).spaces(1)
       .beforeInside(ANNOTATION, NAMED_PARAMETER).none()
+      .beforeInside(ANNOTATION, TYPE_DECLARATION_STATEMENT).none()
+      .beforeInside(ANNOTATION, ASSIGNMENT_STATEMENT).none()
       .afterInside(COLON, ANNOTATION).spaces(1)
       .afterInside(RARROW, ANNOTATION).spaces(1)
 

python/testData/formatter/variableAnnotations.py

@@ -0,0 +1,2 @@
+x    :  int
+y    :  Optional[str] =  'foo'

python/testData/formatter/variableAnnotations_after.py

@@ -0,0 +1,2 @@
+x: int
+y: Optional[str] = 'foo'

python/testSrc/com/jetbrains/python/PyFormatterTest.java

@@ -673,4 +673,8 @@ public class PyFormatterTest extends PyTestCase {
     getCommonCodeStyleSettings().SPACE_AFTER_COMMA = false;
     doTest();
   }
+
+  public void testVariableAnnotations() {
+    runWithLanguageLevel(LanguageLevel.PYTHON36, this::doTest);
+  }
 }