Fix switch new lines (#1156)

.#1136 accidentally removed all the empty lines between statements inside of switch cases. I just brough back the logic and made sure to only use it for everything but the last line.

src/printer.js

@@ -1193,7 +1193,11 @@ function genericPrintNoParens(path, options, print) {
 
       if (n.consequent.find(node => node.type !== "EmptyStatement")) {
         const cons = path.call(consequentPath => {
-          return join(hardline, consequentPath.map(print));
+          return join(hardline, consequentPath.map((p, i) => {
+            const shouldAddLine = i !== n.consequent.length - 1 &&
+              util.isNextLineEmpty(options.originalText, p.getValue());
+            return concat([print(p), shouldAddLine ? hardline : ""]);
+          }));
         }, "consequent");
         parts.push(
           isCurlyBracket(cons)

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

@@ -36,6 +36,18 @@ switch (foo) {
   case \\"baz\\":
     doOtherThing();
 }
+
+switch (x) {
+  case y:
+    call();
+
+    break;
+
+  case z:
+    call();
+
+    break;
+}
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 switch (foo) {
   case \\"bar\\":
@@ -68,6 +80,18 @@ switch (foo) {
   case \\"baz\\":
     doOtherThing();
 }
+
+switch (x) {
+  case y:
+    call();
+
+    break;
+
+  case z:
+    call();
+
+    break;
+}
 "
 `;
 

tests/switch/empty_lines.js

@@ -33,3 +33,15 @@ switch (foo) {
   case "baz":
     doOtherThing();
 }
+
+switch (x) {
+  case y:
+    call();
+
+    break;
+
+  case z:
+    call();
+
+    break;
+}