Merge pull request #2160 from topecongiro/issue-1809

Force vertical layout for all variants if one of then use multiple lines

Author: nrc

src/bin/rustfmt.rs

@@ -45,7 +45,9 @@ enum Operation {
     /// Print detailed configuration help.
     ConfigHelp,
     /// Output default config to a file, or stdout if None
-    ConfigOutputDefault { path: Option<String> },
+    ConfigOutputDefault {
+        path: Option<String>,
+    },
     /// No file specified, read from stdin
     Stdin {
         input: String,

src/items.rs

@@ -484,21 +484,30 @@ impl<'a> FmtVisitor<'a> {
         let indentation = self.block_indent.to_string(self.config);
         result.push_str(&indentation);
 
-        let items = itemize_list(
-            self.codemap,
-            enum_def.variants.iter(),
-            "}",
-            |f| if !f.node.attrs.is_empty() {
-                f.node.attrs[0].span.lo()
-            } else {
-                f.span.lo()
-            },
-            |f| f.span.hi(),
-            |f| self.format_variant(f),
-            body_lo,
-            body_hi,
-            false,
-        );
+        let itemize_list_with = |one_line_width: usize| {
+            itemize_list(
+                self.codemap,
+                enum_def.variants.iter(),
+                "}",
+                |f| if !f.node.attrs.is_empty() {
+                    f.node.attrs[0].span.lo()
+                } else {
+                    f.span.lo()
+                },
+                |f| f.span.hi(),
+                |f| self.format_variant(f, one_line_width),
+                body_lo,
+                body_hi,
+                false,
+            ).collect()
+        };
+        let mut items: Vec<_> = itemize_list_with(self.config.struct_variant_width());
+        // If one of the variants use multiple lines, use multi-lined formatting for all variants.
+        let has_multiline_variant = items.iter().any(|item| item.inner_as_ref().contains("\n"));
+        let has_single_line_variant = items.iter().any(|item| !item.inner_as_ref().contains("\n"));
+        if has_multiline_variant && has_single_line_variant {
+            items = itemize_list_with(0);
+        }
 
         let shape = self.shape().sub_width(2).unwrap();
         let fmt = ListFormatting {
@@ -512,14 +521,14 @@ impl<'a> FmtVisitor<'a> {
             config: self.config,
         };
 
-        let list = write_list(&items.collect::<Vec<_>>(), &fmt)?;
+        let list = write_list(&items, &fmt)?;
         result.push_str(&list);
         result.push('\n');
         Some(result)
     }
 
     // Variant of an enum.
-    fn format_variant(&self, field: &ast::Variant) -> Option<String> {
+    fn format_variant(&self, field: &ast::Variant, one_line_width: usize) -> Option<String> {
         if contains_skip(&field.node.attrs) {
             let lo = field.node.attrs[0].span.lo();
             let span = mk_sp(lo, field.span.hi());
@@ -544,7 +553,7 @@ impl<'a> FmtVisitor<'a> {
                     &context,
                     &StructParts::from_variant(field),
                     indent,
-                    Some(self.config.struct_variant_width()),
+                    Some(one_line_width),
                 )?
             }
             ast::VariantData::Unit(..) => if let Some(ref expr) = field.node.disr_expr {

tests/source/enum.rs

@@ -146,3 +146,22 @@ pub enum ForegroundColor {
 pub enum E<'a> {
     V ( < std::slice::Iter<'a, Xxxxxxxxxxxxxx> as Iterator> :: Item ) ,
 }
+
+// #1809
+enum State {
+    TryRecv {
+        pos: usize,
+        lap: u8,
+        closed_count: usize,
+    },
+    Subscribe { pos: usize },
+    IsReady { pos: usize, ready: bool },
+    Unsubscribe {
+        pos: usize,
+        lap: u8,
+        id_woken: usize,
+    },
+    FinalTryRecv { pos: usize, id_woken: usize },
+    TimedOut,
+    Disconnected,
+}

tests/target/enum.rs

@@ -44,7 +44,9 @@ enum StructLikeVariants {
         // Pre-comment
         #[Attr50] y: SomeType, // Aanother Comment
     },
-    SL { a: A },
+    SL {
+        a: A,
+    },
 }
 
 enum X {
@@ -65,7 +67,10 @@ pub enum EnumWithAttributes {
     SkippedItem(String,String,), // Post-comment
     #[another_attr]
     #[attr2]
-    ItemStruct { x: usize, y: usize }, /* Comment AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA */
+    ItemStruct {
+        x: usize,
+        y: usize,
+    }, /* Comment AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA */
     // And another
     ForcedPreflight, /* AAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
                       * AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA */
@@ -183,3 +188,30 @@ pub enum ForegroundColor {
 pub enum E<'a> {
     V(<std::slice::Iter<'a, Xxxxxxxxxxxxxx> as Iterator>::Item),
 }
+
+// #1809
+enum State {
+    TryRecv {
+        pos: usize,
+        lap: u8,
+        closed_count: usize,
+    },
+    Subscribe {
+        pos: usize,
+    },
+    IsReady {
+        pos: usize,
+        ready: bool,
+    },
+    Unsubscribe {
+        pos: usize,
+        lap: u8,
+        id_woken: usize,
+    },
+    FinalTryRecv {
+        pos: usize,
+        id_woken: usize,
+    },
+    TimedOut,
+    Disconnected,
+}