When default exporting a Flow Enum, do not append semicolon (#8768)

* When default exporting a Flow Enum, do not append semicolon

* Add changelog entry for #8768

changelog_unreleased/flow/pr-8768.md

@@ -0,0 +1,15 @@
+#### Fix export default of Flow Enum ([#8768](https://github.com/prettier/prettier/pull/8768) by [@gkz](https://github.com/gkz))
+
+Do not add a trailing semicolon if default exporting a Flow Enum.
+
+<!-- prettier-ignore -->
+```jsx
+// Input
+export default enum B {}
+
+// Prettier stable
+export default enum B {};
+
+// Prettier master
+export default enum B {}
+```

src/language-js/printer-estree.js

@@ -4064,7 +4064,8 @@ function printExportDeclaration(path, options, print) {
       decl.declaration.type !== "TSInterfaceDeclaration" &&
       decl.declaration.type !== "DeclareClass" &&
       decl.declaration.type !== "DeclareFunction" &&
-      decl.declaration.type !== "TSDeclareFunction"
+      decl.declaration.type !== "TSDeclareFunction" &&
+      decl.declaration.type !== "EnumDeclaration"
     ) {
       parts.push(semi);
     }

tests/flow/enums/__snapshots__/jsfmt.spec.js.snap

@@ -153,7 +153,7 @@ export default enum B {}
 
 export enum A {}
 
-export default enum B {};
+export default enum B {}
 
 ================================================================================
 `;