Preserve lines after directives (#2070)

Looks like we were only doing it at the top level, we should do it everywhere.

Fixes #2067

src/printer.js

@@ -713,6 +713,11 @@ function genericPrintNoParens(path, options, print, args) {
       if (hasDirectives) {
         path.each(childPath => {
           parts.push(indent(concat([hardline, print(childPath), semi])));
+          if (
+            util.isNextLineEmpty(options.originalText, childPath.getValue())
+          ) {
+            parts.push(hardline);
+          }
         }, "directives");
       }
 

tests/directives/__snapshots__/jsfmt.spec.js.snap

@@ -130,6 +130,26 @@ exports[`test.js 1`] = `
 function fn() {
   "use strict";
 }
+
+function f() {
+  'ngInject';
+  Object.assign(this, { $log, $uibModal });
+}
+
+function f() {
+
+  'ngInject';
+
+  Object.assign(this, { $log, $uibModal });
+
+}
+
+function f() {
+  'ngInject';
+
+
+  Object.assign(this, { $log, $uibModal });
+}
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 "use strict";
 
@@ -137,4 +157,21 @@ function fn() {
   "use strict";
 }
 
+function f() {
+  "ngInject";
+  Object.assign(this, { $log, $uibModal });
+}
+
+function f() {
+  "ngInject";
+
+  Object.assign(this, { $log, $uibModal });
+}
+
+function f() {
+  "ngInject";
+
+  Object.assign(this, { $log, $uibModal });
+}
+
 `;

tests/directives/test.js

@@ -3,3 +3,23 @@
 function fn() {
   "use strict";
 }
+
+function f() {
+  'ngInject';
+  Object.assign(this, { $log, $uibModal });
+}
+
+function f() {
+
+  'ngInject';
+
+  Object.assign(this, { $log, $uibModal });
+
+}
+
+function f() {
+  'ngInject';
+
+
+  Object.assign(this, { $log, $uibModal });
+}