If a string goes over-width, give up formatting it

Logic here is that the original might be better and at best we'll only make it a different kind of bad.

Fixes #1237

src/expr.rs

@@ -64,7 +64,7 @@ fn format_expr(expr: &ast::Expr,
         ast::ExprKind::Lit(ref l) => {
             match l.node {
                 ast::LitKind::Str(_, ast::StrStyle::Cooked) => {
-                    rewrite_string_lit(context, l.span, width, offset)
+                    Some(rewrite_string_lit(context, l.span, width, offset))
                 }
                 _ => {
                     wrap_str(context.snippet(expr.span),
@@ -1457,16 +1457,16 @@ fn rewrite_string_lit(context: &RewriteContext,
                       span: Span,
                       width: usize,
                       offset: Indent)
-                      -> Option<String> {
+                      -> String {
     let string_lit = context.snippet(span);
 
     if !context.config.format_strings && !context.config.force_format_strings {
-        return Some(string_lit);
+        return string_lit;
     }
 
     if !context.config.force_format_strings &&
        !string_requires_rewrite(context, span, &string_lit, width, offset) {
-        return Some(string_lit);
+        return string_lit;
     }
 
     let fmt = StringFormat {
@@ -1483,7 +1483,7 @@ fn rewrite_string_lit(context: &RewriteContext,
     // Remove the quote characters.
     let str_lit = &string_lit[1..string_lit.len() - 1];
 
-    rewrite_string(str_lit, &fmt)
+    rewrite_string(str_lit, &fmt).unwrap_or_else(|| string_lit.to_owned())
 }
 
 fn string_requires_rewrite(context: &RewriteContext,

src/string.rs

@@ -15,6 +15,7 @@ use regex::Regex;
 
 use Indent;
 use config::Config;
+use utils::wrap_str;
 
 use MIN_STRING;
 
@@ -117,7 +118,7 @@ pub fn rewrite_string<'a>(orig: &str, fmt: &StringFormat<'a>) -> Option<String>
     }
 
     result.push_str(fmt.closer);
-    Some(result)
+    wrap_str(result, fmt.config.max_width, fmt.width, fmt.offset)
 }
 
 #[cfg(test)]

tests/source/string-lit-2.rs

@@ -3,8 +3,23 @@ fn main() -> &'static str {
     let leave_me = "sssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssss\
                     s
                     jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj";
-    // Crappy formatting :-(
-    let change_me = "ssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssss\
-                     s
-                     jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj";
+}
+
+fn issue_1237() {
+    let msg = "eedadn\n\
+               drvtee\n\
+               eandsr\n\
+               raavrd\n\
+               atevrs\n\
+               tsrnev\n\
+               sdttsa\n\
+               rasrtv\n\
+               nssdts\n\
+               ntnada\n\
+               svetve\n\
+               tesnvt\n\
+               vntsnd\n\
+               vrdear\n\
+               dvrsen\n\
+               enarar";
 }

tests/target/enum.rs

@@ -48,8 +48,7 @@ enum StructLikeVariants {
 enum X {
     CreateWebGLPaintTask(Size2D<i32>,
                          GLContextAttributes,
-                         IpcSender<Result<(IpcSender<CanvasMsg>, usize), String>>), /* This is
-                                                                                     * a post comment */
+                         IpcSender<Result<(IpcSender<CanvasMsg>, usize), String>>), /* This is a post comment */
 }
 
 pub enum EnumWithAttributes {
@@ -71,8 +70,7 @@ pub enum EnumWithAttributes {
 pub enum SingleTuple {
     // Pre Comment AAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
     // AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
-    Match(usize, usize, String), /* Post-comment
-                                  * AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA */
+    Match(usize, usize, String), /* Post-comment AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA */
 }
 
 pub enum SingleStruct {

tests/target/string-lit-2.rs

@@ -3,8 +3,23 @@ fn main() -> &'static str {
     let leave_me = "sssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssss\
                     s
                     jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj";
-    // Crappy formatting :-(
-    let change_me = "sssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssss
-                     \
-                     jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj";
+}
+
+fn issue_1237() {
+    let msg = "eedadn\n\
+               drvtee\n\
+               eandsr\n\
+               raavrd\n\
+               atevrs\n\
+               tsrnev\n\
+               sdttsa\n\
+               rasrtv\n\
+               nssdts\n\
+               ntnada\n\
+               svetve\n\
+               tesnvt\n\
+               vntsnd\n\
+               vrdear\n\
+               dvrsen\n\
+               enarar";
 }