Merge pull request #3661 from calebcartwright/associated-type-bounds

fix handling on associated type bounds

Author: scampi

src/types.rs

@@ -168,14 +168,22 @@ impl<'a> Rewrite for SegmentParam<'a> {
             SegmentParam::LifeTime(lt) => lt.rewrite(context, shape),
             SegmentParam::Type(ty) => ty.rewrite(context, shape),
             SegmentParam::Binding(assoc_ty_constraint) => {
-                let mut result = match context.config.type_punctuation_density() {
-                    TypeDensity::Wide => {
-                        format!("{} = ", rewrite_ident(context, assoc_ty_constraint.ident))
+                let mut result = match assoc_ty_constraint.kind {
+                    ast::AssocTyConstraintKind::Bound { .. } => {
+                        format!("{}: ", rewrite_ident(context, assoc_ty_constraint.ident))
                     }
-                    TypeDensity::Compressed => {
-                        format!("{}=", rewrite_ident(context, assoc_ty_constraint.ident))
+                    ast::AssocTyConstraintKind::Equality { .. } => {
+                        match context.config.type_punctuation_density() {
+                            TypeDensity::Wide => {
+                                format!("{} = ", rewrite_ident(context, assoc_ty_constraint.ident))
+                            }
+                            TypeDensity::Compressed => {
+                                format!("{}=", rewrite_ident(context, assoc_ty_constraint.ident))
+                            }
+                        }
                     }
                 };
+
                 let budget = shape.width.checked_sub(result.len())?;
                 let rewrite = assoc_ty_constraint
                     .kind

tests/source/associated_type_bounds.rs

@@ -0,0 +1,13 @@
+// See #3657 - https://github.com/rust-lang/rustfmt/issues/3657
+
+#![feature(associated_type_bounds)]
+
+fn f<I: Iterator<Item: Clone>>() {}
+
+fn g<I: Iterator<Item : Clone>>() {}
+
+fn h<I: Iterator<Item :      Clone>>() {}
+
+fn i<I: Iterator<Item:Clone>>() {}
+
+fn j<I: Iterator<Item :  Clone+'a>>() {}

tests/target/associated_type_bounds.rs

@@ -0,0 +1,13 @@
+// See #3657 - https://github.com/rust-lang/rustfmt/issues/3657
+
+#![feature(associated_type_bounds)]
+
+fn f<I: Iterator<Item: Clone>>() {}
+
+fn g<I: Iterator<Item: Clone>>() {}
+
+fn h<I: Iterator<Item: Clone>>() {}
+
+fn i<I: Iterator<Item: Clone>>() {}
+
+fn j<I: Iterator<Item: Clone + 'a>>() {}