Split AstBuilder::pat_enum into pat_tuple_struct and pat_path

Author: petrochenkov

src/libsyntax/ext/build.rs

@@ -171,9 +171,11 @@ pub trait AstBuilder {
                               span: Span,
                               ident: ast::Ident,
                               bm: ast::BindingMode) -> P<ast::Pat>;
-    fn pat_enum(&self, span: Span, path: ast::Path, subpats: Vec<P<ast::Pat>> ) -> P<ast::Pat>;
-    fn pat_struct(&self, span: Span,
-                  path: ast::Path, field_pats: Vec<Spanned<ast::FieldPat>> ) -> P<ast::Pat>;
+    fn pat_path(&self, span: Span, path: ast::Path) -> P<ast::Pat>;
+    fn pat_tuple_struct(&self, span: Span, path: ast::Path,
+                        subpats: Vec<P<ast::Pat>>) -> P<ast::Pat>;
+    fn pat_struct(&self, span: Span, path: ast::Path,
+                  field_pats: Vec<Spanned<ast::FieldPat>>) -> P<ast::Pat>;
     fn pat_tuple(&self, span: Span, pats: Vec<P<ast::Pat>>) -> P<ast::Pat>;
 
     fn pat_some(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat>;
@@ -802,10 +804,10 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
         let binding_expr = self.expr_ident(sp, binding_variable);
 
         // Ok(__try_var) pattern
-        let ok_pat = self.pat_enum(sp, ok_path, vec!(binding_pat.clone()));
+        let ok_pat = self.pat_tuple_struct(sp, ok_path, vec![binding_pat.clone()]);
 
         // Err(__try_var)  (pattern and expression resp.)
-        let err_pat = self.pat_enum(sp, err_path.clone(), vec!(binding_pat));
+        let err_pat = self.pat_tuple_struct(sp, err_path.clone(), vec![binding_pat]);
         let err_inner_expr = self.expr_call(sp, self.expr_path(err_path),
                                             vec!(binding_expr.clone()));
         // return Err(__try_var)
@@ -842,18 +844,16 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
         let pat = PatKind::Ident(bm, Spanned{span: span, node: ident}, None);
         self.pat(span, pat)
     }
-    fn pat_enum(&self, span: Span, path: ast::Path, subpats: Vec<P<ast::Pat>>) -> P<ast::Pat> {
-        let pat = if subpats.is_empty() {
-            PatKind::Struct(path, Vec::new(), false)
-        } else {
-            PatKind::TupleStruct(path, subpats, None)
-        };
-        self.pat(span, pat)
+    fn pat_path(&self, span: Span, path: ast::Path) -> P<ast::Pat> {
+        self.pat(span, PatKind::Path(None, path))
     }
-    fn pat_struct(&self, span: Span,
-                  path: ast::Path, field_pats: Vec<Spanned<ast::FieldPat>>) -> P<ast::Pat> {
-        let pat = PatKind::Struct(path, field_pats, false);
-        self.pat(span, pat)
+    fn pat_tuple_struct(&self, span: Span, path: ast::Path,
+                        subpats: Vec<P<ast::Pat>>) -> P<ast::Pat> {
+        self.pat(span, PatKind::TupleStruct(path, subpats, None))
+    }
+    fn pat_struct(&self, span: Span, path: ast::Path,
+                  field_pats: Vec<Spanned<ast::FieldPat>>) -> P<ast::Pat> {
+        self.pat(span, PatKind::Struct(path, field_pats, false))
     }
     fn pat_tuple(&self, span: Span, pats: Vec<P<ast::Pat>>) -> P<ast::Pat> {
         self.pat(span, PatKind::Tuple(pats, None))
@@ -862,25 +862,25 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
     fn pat_some(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat> {
         let some = self.std_path(&["option", "Option", "Some"]);
         let path = self.path_global(span, some);
-        self.pat_enum(span, path, vec!(pat))
+        self.pat_tuple_struct(span, path, vec![pat])
     }
 
     fn pat_none(&self, span: Span) -> P<ast::Pat> {
         let some = self.std_path(&["option", "Option", "None"]);
         let path = self.path_global(span, some);
-        self.pat_enum(span, path, vec!())
+        self.pat_path(span, path)
     }
 
     fn pat_ok(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat> {
         let some = self.std_path(&["result", "Result", "Ok"]);
         let path = self.path_global(span, some);
-        self.pat_enum(span, path, vec!(pat))
+        self.pat_tuple_struct(span, path, vec![pat])
     }
 
     fn pat_err(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat> {
         let some = self.std_path(&["result", "Result", "Err"]);
         let path = self.path_global(span, some);
-        self.pat_enum(span, path, vec!(pat))
+        self.pat_tuple_struct(span, path, vec![pat])
     }
 
     fn arm(&self, _span: Span, pats: Vec<P<ast::Pat>>, expr: P<ast::Expr>) -> ast::Arm {

src/libsyntax_ext/deriving/cmp/ord.rs

@@ -104,7 +104,7 @@ pub fn cs_cmp(cx: &mut ExtCtxt, span: Span, substr: &Substructure) -> P<Expr> {
         };
 
         let eq_arm = cx.arm(span,
-                            vec![cx.pat_enum(span, equals_path.clone(), vec![])],
+                            vec![cx.pat_path(span, equals_path.clone())],
                             old);
         let neq_arm = cx.arm(span,
                              vec![cx.pat_ident(span, test_id)],

src/libsyntax_ext/deriving/cmp/partial_ord.rs

@@ -165,7 +165,7 @@ pub fn cs_partial_cmp(cx: &mut ExtCtxt, span: Span, substr: &Substructure) -> P<
         };
 
         let eq_arm = cx.arm(span,
-                            vec![cx.pat_some(span, cx.pat_enum(span, ordering.clone(), vec![]))],
+                            vec![cx.pat_some(span, cx.pat_path(span, ordering.clone()))],
                             old);
         let neq_arm = cx.arm(span,
                              vec![cx.pat_ident(span, test_id)],

src/libsyntax_ext/deriving/generic/mod.rs

@@ -1510,26 +1510,32 @@ impl<'a> TraitDef<'a> {
         }
 
         let subpats = self.create_subpatterns(cx, paths, mutbl);
-        let pattern = if struct_def.is_struct() {
-            let field_pats = subpats.into_iter()
-                .zip(&ident_exprs)
-                .map(|(pat, &(sp, ident, _, _))| {
-                    if ident.is_none() {
-                        cx.span_bug(sp, "a braced struct with unnamed fields in `derive`");
-                    }
-                    codemap::Spanned {
-                        span: pat.span,
-                        node: ast::FieldPat {
-                            ident: ident.unwrap(),
-                            pat: pat,
-                            is_shorthand: false,
-                        },
-                    }
-                })
-                .collect();
-            cx.pat_struct(self.span, struct_path, field_pats)
-        } else {
-            cx.pat_enum(self.span, struct_path, subpats)
+        let pattern = match *struct_def {
+            VariantData::Struct(..) => {
+                let field_pats = subpats.into_iter()
+                    .zip(&ident_exprs)
+                    .map(|(pat, &(sp, ident, _, _))| {
+                        if ident.is_none() {
+                            cx.span_bug(sp, "a braced struct with unnamed fields in `derive`");
+                        }
+                        codemap::Spanned {
+                            span: pat.span,
+                            node: ast::FieldPat {
+                                ident: ident.unwrap(),
+                                pat: pat,
+                                is_shorthand: false,
+                            },
+                        }
+                    })
+                    .collect();
+                cx.pat_struct(self.span, struct_path, field_pats)
+            }
+            VariantData::Tuple(..) => {
+                cx.pat_tuple_struct(self.span, struct_path, subpats)
+            }
+            VariantData::Unit(..) => {
+                cx.pat_path(self.span, struct_path)
+            }
         };
 
         (pattern, ident_exprs)