Avoid putting a long macro call in a single line

Author: topecongiro

src/overflow.rs

@@ -11,6 +11,7 @@
 //! Rewrite a list some items with overflow.
 
 use config::lists::*;
+use config::Version;
 use syntax::parse::token::DelimToken;
 use syntax::source_map::Span;
 use syntax::{ast, ptr};
@@ -632,8 +633,6 @@ impl<'a> Context<'a> {
             _ => (self.prefix, self.suffix),
         };
 
-        // 2 = `()`
-        let fits_one_line = items_str.len() + 2 <= shape.width;
         let extend_width = if items_str.is_empty() {
             2
         } else {
@@ -652,10 +651,16 @@ impl<'a> Context<'a> {
         );
         result.push_str(self.ident);
         result.push_str(prefix);
-        if !self.context.use_block_indent()
-            || (self.context.inside_macro() && !items_str.contains('\n') && fits_one_line)
-            || (is_extendable && extend_width <= shape.width)
-        {
+        let force_single_line = if self.context.config.version() == Version::Two {
+            !self.context.use_block_indent() || (is_extendable && extend_width <= shape.width)
+        } else {
+            // 2 = `()`
+            let fits_one_line = items_str.len() + 2 <= shape.width;
+            !self.context.use_block_indent()
+                || (self.context.inside_macro() && !items_str.contains('\n') && fits_one_line)
+                || (is_extendable && extend_width <= shape.width)
+        };
+        if force_single_line {
             result.push_str(items_str);
         } else {
             if !items_str.is_empty() {

tests/source/macros.rs

@@ -400,14 +400,6 @@ fn foo() {
     foo!(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,);
 }
 
-// #2652
-// Preserve trailing comma inside macro, even if it looks an array.
-macro_rules! bar {
-    ($m:ident) => {
-        $m!([a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z]);
-    };
-}
-
 // #2830
 // Preserve trailing comma-less/ness inside nested macro.
 named!(

tests/source/single-line-macro/v1.rs

@@ -0,0 +1,10 @@
+// rustfmt-version: One
+
+// #2652
+// Preserve trailing comma inside macro, even if it looks an array.
+macro_rules! bar {
+    ($m:ident) => {
+        $m!([a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z,]);
+        $m!([a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z]);
+    };
+}

tests/source/single-line-macro/v2.rs

@@ -0,0 +1,10 @@
+// rustfmt-version: Two
+
+// #2652
+// Preserve trailing comma inside macro, even if it looks an array.
+macro_rules! bar {
+    ($m:ident) => {
+        $m!([a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z,]);
+        $m!([a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z]);
+    };
+}

tests/target/macros.rs

@@ -980,14 +980,6 @@ fn foo() {
     );
 }
 
-// #2652
-// Preserve trailing comma inside macro, even if it looks an array.
-macro_rules! bar {
-    ($m:ident) => {
-        $m!([a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z]);
-    };
-}
-
 // #2830
 // Preserve trailing comma-less/ness inside nested macro.
 named!(

tests/target/single-line-macro/v1.rs

@@ -0,0 +1,10 @@
+// rustfmt-version: One
+
+// #2652
+// Preserve trailing comma inside macro, even if it looks an array.
+macro_rules! bar {
+    ($m:ident) => {
+        $m!([a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z,]);
+        $m!([a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z]);
+    };
+}

tests/target/single-line-macro/v2.rs

@@ -0,0 +1,14 @@
+// rustfmt-version: Two
+
+// #2652
+// Preserve trailing comma inside macro, even if it looks an array.
+macro_rules! bar {
+    ($m:ident) => {
+        $m!([
+            a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z,
+        ]);
+        $m!([
+            a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z
+        ]);
+    };
+}