Optimize `ast::PathSegment`.

2 files changed, 23 insertions, 70 deletions

diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs
index c982205f0ec..b9e6605639e 100644
--- a/src/libsyntax/parse/mod.rs
+++ b/src/libsyntax/parse/mod.rs
@@ -634,12 +634,7 @@ mod tests {
                     node: ast::ExprKind::Path(None, ast::Path {
                         span: sp(0, 1),
                         global: false,
-                        segments: vec![
-                            ast::PathSegment {
-                                identifier: Ident::from_str("a"),
-                                parameters: ast::PathParameters::none(),
-                            }
-                        ],
+                        segments: vec![Ident::from_str("a").into()],
                     }),
                     span: sp(0, 1),
                     attrs: ThinVec::new(),
@@ -651,19 +646,10 @@ mod tests {
                    P(ast::Expr {
                     id: ast::DUMMY_NODE_ID,
                     node: ast::ExprKind::Path(None, ast::Path {
-                            span: sp(0, 6),
-                            global: true,
-                            segments: vec![
-                                ast::PathSegment {
-                                    identifier: Ident::from_str("a"),
-                                    parameters: ast::PathParameters::none(),
-                                },
-                                ast::PathSegment {
-                                    identifier: Ident::from_str("b"),
-                                    parameters: ast::PathParameters::none(),
-                                }
-                            ]
-                        }),
+                        span: sp(0, 6),
+                        global: true,
+                        segments: vec![Ident::from_str("a").into(), Ident::from_str("b").into()],
+                    }),
                     span: sp(0, 6),
                     attrs: ThinVec::new(),
                    }))
@@ -772,12 +758,7 @@ mod tests {
                         node:ast::ExprKind::Path(None, ast::Path{
                             span: sp(7, 8),
                             global: false,
-                            segments: vec![
-                                ast::PathSegment {
-                                    identifier: Ident::from_str("d"),
-                                    parameters: ast::PathParameters::none(),
-                                }
-                            ],
+                            segments: vec![Ident::from_str("d").into()],
                         }),
                         span:sp(7,8),
                         attrs: ThinVec::new(),
@@ -795,12 +776,7 @@ mod tests {
                            node: ast::ExprKind::Path(None, ast::Path {
                                span:sp(0,1),
                                global:false,
-                               segments: vec![
-                                ast::PathSegment {
-                                    identifier: Ident::from_str("b"),
-                                    parameters: ast::PathParameters::none(),
-                                }
-                               ],
+                               segments: vec![Ident::from_str("b").into()],
                             }),
                            span: sp(0,1),
                            attrs: ThinVec::new()})),
@@ -842,12 +818,7 @@ mod tests {
                                                   node: ast::TyKind::Path(None, ast::Path{
                                         span:sp(10,13),
                                         global:false,
-                                        segments: vec![
-                                            ast::PathSegment {
-                                                identifier: Ident::from_str("i32"),
-                                                parameters: ast::PathParameters::none(),
-                                            }
-                                        ],
+                                        segments: vec![Ident::from_str("i32").into()],
                                         }),
                                         span:sp(10,13)
                                     }),
@@ -890,13 +861,7 @@ mod tests {
                                                       ast::Path{
                                                         span:sp(17,18),
                                                         global:false,
-                                                        segments: vec![
-                                                            ast::PathSegment {
-                                                                identifier: Ident::from_str("b"),
-                                                                parameters:
-                                                                ast::PathParameters::none(),
-                                                            }
-                                                        ],
+                                                        segments: vec![Ident::from_str("b").into()],
                                                       }),
                                                 span: sp(17,18),
                                                 attrs: ThinVec::new()})),
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index a1d4ad9d629..72462b74e68 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -1705,12 +1705,11 @@ impl<'a> Parser<'a> {
             // Parse types, optionally.
             let parameters = if self.eat_lt() {
                 let (lifetimes, types, bindings) = self.parse_generic_values_after_lt()?;
-
-                ast::PathParameters::AngleBracketed(ast::AngleBracketedParameterData {
+                ast::AngleBracketedParameterData {
                     lifetimes: lifetimes,
                     types: P::from_vec(types),
                     bindings: P::from_vec(bindings),
-                })
+                }.into()
             } else if self.eat(&token::OpenDelim(token::Paren)) {
                 let lo = self.prev_span.lo;
 
@@ -1727,18 +1726,17 @@ impl<'a> Parser<'a> {
 
                 let hi = self.prev_span.hi;
 
-                ast::PathParameters::Parenthesized(ast::ParenthesizedParameterData {
+                Some(P(ast::PathParameters::Parenthesized(ast::ParenthesizedParameterData {
                     span: mk_sp(lo, hi),
                     inputs: inputs,
                     output: output_ty,
-                })
+                })))
             } else {
-                ast::PathParameters::none()
+                None
             };
 
             // Assemble and push the result.
-            segments.push(ast::PathSegment { identifier: identifier,
-                                             parameters: parameters });
+            segments.push(ast::PathSegment { identifier: identifier, parameters: parameters });
 
             // Continue only if we see a `::`
             if !self.eat(&token::ModSep) {
@@ -1757,10 +1755,7 @@ impl<'a> Parser<'a> {
 
             // If we do not see a `::`, stop.
             if !self.eat(&token::ModSep) {
-                segments.push(ast::PathSegment {
-                    identifier: identifier,
-                    parameters: ast::PathParameters::none()
-                });
+                segments.push(identifier.into());
                 return Ok(segments);
             }
 
@@ -1768,14 +1763,13 @@ impl<'a> Parser<'a> {
             if self.eat_lt() {
                 // Consumed `a::b::<`, go look for types
                 let (lifetimes, types, bindings) = self.parse_generic_values_after_lt()?;
-                let parameters = ast::AngleBracketedParameterData {
-                    lifetimes: lifetimes,
-                    types: P::from_vec(types),
-                    bindings: P::from_vec(bindings),
-                };
                 segments.push(ast::PathSegment {
                     identifier: identifier,
-                    parameters: ast::PathParameters::AngleBracketed(parameters),
+                    parameters: ast::AngleBracketedParameterData {
+                        lifetimes: lifetimes,
+                        types: P::from_vec(types),
+                        bindings: P::from_vec(bindings),
+                    }.into(),
                 });
 
                 // Consumed `a::b::<T,U>`, check for `::` before proceeding
@@ -1784,10 +1778,7 @@ impl<'a> Parser<'a> {
                 }
             } else {
                 // Consumed `a::`, go look for `b`
-                segments.push(ast::PathSegment {
-                    identifier: identifier,
-                    parameters: ast::PathParameters::none(),
-                });
+                segments.push(identifier.into());
             }
         }
     }
@@ -1802,10 +1793,7 @@ impl<'a> Parser<'a> {
             let identifier = self.parse_path_segment_ident()?;
 
             // Assemble and push the result.
-            segments.push(ast::PathSegment {
-                identifier: identifier,
-                parameters: ast::PathParameters::none()
-            });
+            segments.push(identifier.into());
 
             // If we do not see a `::` or see `::{`/`::*`, stop.
             if !self.check(&token::ModSep) || self.is_import_coupler() {