Add support for formatting "return" expressions.

Fixes #303.

src/expr.rs

@@ -153,13 +153,18 @@ impl Rewrite for ast::Expr {
             ast::Expr_::ExprMac(ref mac) => {
                 rewrite_macro(mac, context, width, offset)
             }
+            ast::Expr_::ExprRet(None) => {
+                wrap_str("return".to_owned(), context.config.max_width, width, offset)
+            }
+            ast::Expr_::ExprRet(Some(ref expr)) => {
+                rewrite_unary_prefix(context, "return ", &expr, width, offset)
+            }
             // We do not format these expressions yet, but they should still
             // satisfy our width restrictions.
             ast::Expr_::ExprBox(..) |
             ast::Expr_::ExprCast(..) |
             ast::Expr_::ExprIndex(..) |
             ast::Expr_::ExprAddrOf(..) |
-            ast::Expr_::ExprRet(..) |
             ast::Expr_::ExprInlineAsm(..) |
             ast::Expr_::ExprRepeat(..) => {
                 wrap_str(context.snippet(self.span), context.config.max_width, width, offset)
@@ -1294,6 +1299,16 @@ fn rewrite_binary_op(context: &RewriteContext,
                  rhs_result))
 }
 
+fn rewrite_unary_prefix(context: &RewriteContext,
+                        prefix: &str,
+                        expr: &ast::Expr,
+                        width: usize,
+                        offset: Indent)
+                        -> Option<String> {
+    expr.rewrite(context, try_opt!(width.checked_sub(prefix.len())), offset + prefix.len())
+        .map(|r| format!("{}{}", prefix, r))
+}
+
 fn rewrite_unary_op(context: &RewriteContext,
                     op: &ast::UnOp,
                     expr: &ast::Expr,
@@ -1307,10 +1322,7 @@ fn rewrite_unary_op(context: &RewriteContext,
         ast::UnOp::UnNot => "!",
         ast::UnOp::UnNeg => "-",
     };
-    let operator_len = operator_str.len();
-
-    expr.rewrite(context, try_opt!(width.checked_sub(operator_len)), offset + operator_len)
-        .map(|r| format!("{}{}", operator_str, r))
+    rewrite_unary_prefix(context, operator_str, expr, width, offset)
 }
 
 fn rewrite_assignment(context: &RewriteContext,

src/issues.rs

@@ -144,9 +144,9 @@ impl BadIssueSeeker {
                             true
                         } else {
                             false
-                        }
+                        },
                     },
-                    part: NumberPart::OpenParen
+                    part: NumberPart::OpenParen,
                 };
             }
             fixme_idx = 0;
@@ -162,9 +162,9 @@ impl BadIssueSeeker {
                             true
                         } else {
                             false
-                        }
+                        },
                     },
-                    part: NumberPart::OpenParen
+                    part: NumberPart::OpenParen,
                 };
             }
             todo_idx = 0;

tests/source/expr.rs

@@ -183,3 +183,9 @@ fn arrays() {
 
     [ 1 +   3, 4 ,  5, 6, 7, 7, fncall::<Vec<_>>(3-1)]
 }
+
+fn returns() {
+    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa && return;
+
+    return aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa + aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa;
+}

tests/target/expr.rs

@@ -195,3 +195,11 @@ fn arrays() {
 
     [1 + 3, 4, 5, 6, 7, 7, fncall::<Vec<_>>(3 - 1)]
 }
+
+fn returns() {
+    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa &&
+    return;
+
+    return aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa +
+           aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa;
+}