Add tests for async & async move

src/expr.rs

@@ -345,17 +345,28 @@ pub fn format_expr(
         }
         // FIXME(#2743)
         ast::ExprKind::ObsoleteInPlace(..) => unimplemented!(),
-        ast::ExprKind::Async(_capture_by, _node_id, ref block) => {
-            if let rw @ Some(_) =
-                rewrite_single_line_block(context, "async ", block, Some(&expr.attrs), None, shape)
-            {
+        ast::ExprKind::Async(capture_by, _node_id, ref block) => {
+            let mover = if capture_by == ast::CaptureBy::Value {
+                "move "
+            } else {
+                ""
+            };
+            if let rw @ Some(_) = rewrite_single_line_block(
+                context,
+                format!("{}{}", "async ", mover).as_str(),
+                block,
+                Some(&expr.attrs),
+                None,
+                shape,
+            ) {
                 rw
             } else {
                 // 6 = `async `
                 let budget = shape.width.saturating_sub(6);
                 Some(format!(
-                    "{}{}",
+                    "{}{}{}",
                     "async ",
+                    mover,
                     rewrite_block(
                         block,
                         Some(&expr.attrs),

src/items.rs

@@ -239,9 +239,9 @@ impl<'a> FnSig<'a> {
         // Vis defaultness constness unsafety abi.
         result.push_str(&*format_visibility(context, &self.visibility));
         result.push_str(format_defaultness(self.defaultness));
-        result.push_str(format_asyncness(self.asyncness));
         result.push_str(format_constness(self.constness));
         result.push_str(format_unsafety(self.unsafety));
+        result.push_str(format_asyncness(self.asyncness));
         result.push_str(&format_abi(
             self.abi,
             context.config.force_explicit_abi(),

tests/source/async_block.rs

@@ -0,0 +1,7 @@
+// rustfmt-edition: Edition2018
+
+fn main() {
+    let x = async {
+        Ok(())
+    };
+}

tests/source/async_fn.rs

@@ -0,0 +1,15 @@
+// rustfmt-edition: Edition2018
+
+async fn bar() -> Result<(), ()> {
+    Ok(())
+}
+
+pub async fn baz() -> Result<(), ()> {
+    Ok(())
+}
+
+unsafe async fn foo() {
+    async move {
+        Ok(())
+    }
+}

tests/target/async_block.rs

@@ -0,0 +1,5 @@
+// rustfmt-edition: Edition2018
+
+fn main() {
+    let x = async { Ok(()) };
+}

tests/target/async_fn.rs

@@ -0,0 +1,13 @@
+// rustfmt-edition: Edition2018
+
+async fn bar() -> Result<(), ()> {
+    Ok(())
+}
+
+pub async fn baz() -> Result<(), ()> {
+    Ok(())
+}
+
+unsafe async fn foo() {
+    async move { Ok(()) }
+}