rustdoc: Display tuple structs correctly

The fields of tuple structs recently gained the ability to have privacy
associated with them, but rustdoc was not updated accodingly. This moves the
struct field filtering to the rendering phase in order to preserve the ordering
of struct fields to allow tuple structs to have their private fields printed as
underscores.

Closes #13594

3 files changed, 51 insertions, 23 deletions

diff --git a/src/librustdoc/clean.rs b/src/librustdoc/clean.rs
index fcd6629096c..3f1c99cffd6 100644
--- a/src/librustdoc/clean.rs
+++ b/src/librustdoc/clean.rs
@@ -652,7 +652,7 @@ pub enum Type {
     Proc(~ClosureDecl),
     /// extern "ABI" fn
     BareFunction(~BareFunctionDecl),
-    Tuple(Vec<Type> ),
+    Tuple(Vec<Type>),
     Vector(~Type),
     FixedVector(~Type, ~str),
     String,
@@ -713,25 +713,24 @@ impl Clean<Type> for ast::Ty {
 }
 
 #[deriving(Clone, Encodable, Decodable)]
-pub struct StructField {
-    pub type_: Type,
+pub enum StructField {
+    HiddenStructField,
+    TypedStructField(Type),
 }
 
 impl Clean<Item> for ast::StructField {
     fn clean(&self) -> Item {
         let (name, vis) = match self.node.kind {
-            ast::NamedField(id, vis) => (Some(id), Some(vis)),
-            _ => (None, None)
+            ast::NamedField(id, vis) => (Some(id), vis),
+            ast::UnnamedField(vis) => (None, vis)
         };
         Item {
             name: name.clean(),
             attrs: self.node.attrs.clean().move_iter().collect(),
             source: self.span.clean(),
-            visibility: vis,
+            visibility: Some(vis),
             id: self.node.id,
-            inner: StructFieldItem(StructField {
-                type_: self.node.ty.clean(),
-            }),
+            inner: StructFieldItem(TypedStructField(self.node.ty.clean())),
         }
     }
 }
@@ -837,7 +836,7 @@ impl Clean<Item> for doctree::Variant {
 #[deriving(Clone, Encodable, Decodable)]
 pub enum VariantKind {
     CLikeVariant,
-    TupleVariant(Vec<Type> ),
+    TupleVariant(Vec<Type>),
     StructVariant(VariantStruct),
 }
 
diff --git a/src/librustdoc/html/render.rs b/src/librustdoc/html/render.rs
index 4ccba7a1f44..aff9a29c838 100644
--- a/src/librustdoc/html/render.rs
+++ b/src/librustdoc/html/render.rs
@@ -1345,16 +1345,22 @@ fn item_struct(w: &mut Writer, it: &clean::Item,
                        Some(&s.generics),
                        s.struct_type,
                        s.fields.as_slice(),
-                       s.fields_stripped,
                        "",
                        true));
     try!(write!(w, "</pre>"));
 
     try!(document(w, it));
+    let mut fields = s.fields.iter().filter(|f| {
+        match f.inner {
+            clean::StructFieldItem(clean::HiddenStructField) => false,
+            clean::StructFieldItem(clean::TypedStructField(..)) => true,
+            _ => false,
+        }
+    }).peekable();
     match s.struct_type {
-        doctree::Plain if s.fields.len() > 0 => {
+        doctree::Plain if fields.peek().is_some() => {
             try!(write!(w, "<h2 class='fields'>Fields</h2>\n<table>"));
-            for field in s.fields.iter() {
+            for field in fields {
                 try!(write!(w, "<tr><td id='structfield.{name}'>\
                                   <code>{name}</code></td><td>",
                               name = field.name.get_ref().as_slice()));
@@ -1400,7 +1406,6 @@ fn item_enum(w: &mut Writer, it: &clean::Item, e: &clean::Enum) -> fmt::Result {
                                                None,
                                                s.struct_type,
                                                s.fields.as_slice(),
-                                               s.fields_stripped,
                                                "    ",
                                                false));
                         }
@@ -1429,9 +1434,18 @@ fn item_enum(w: &mut Writer, it: &clean::Item, e: &clean::Enum) -> fmt::Result {
                 clean::VariantItem(ref var) => {
                     match var.kind {
                         clean::StructVariant(ref s) => {
+                            let mut fields = s.fields.iter().filter(|f| {
+                                match f.inner {
+                                    clean::StructFieldItem(ref t) => match *t {
+                                        clean::HiddenStructField => false,
+                                        clean::TypedStructField(..) => true,
+                                    },
+                                    _ => false,
+                                }
+                            });
                             try!(write!(w, "<h3 class='fields'>Fields</h3>\n
                                               <table>"));
-                            for field in s.fields.iter() {
+                            for field in fields {
                                 try!(write!(w, "<tr><td \
                                                   id='variant.{v}.field.{f}'>\
                                                   <code>{f}</code></td><td>",
@@ -1460,7 +1474,6 @@ fn render_struct(w: &mut Writer, it: &clean::Item,
                  g: Option<&clean::Generics>,
                  ty: doctree::StructType,
                  fields: &[clean::Item],
-                 fields_stripped: bool,
                  tab: &str,
                  structhead: bool) -> fmt::Result {
     try!(write!(w, "{}{}{}",
@@ -1474,17 +1487,21 @@ fn render_struct(w: &mut Writer, it: &clean::Item,
     match ty {
         doctree::Plain => {
             try!(write!(w, " \\{\n{}", tab));
+            let mut fields_stripped = false;
             for field in fields.iter() {
                 match field.inner {
-                    clean::StructFieldItem(ref ty) => {
+                    clean::StructFieldItem(clean::HiddenStructField) => {
+                        fields_stripped = true;
+                    }
+                    clean::StructFieldItem(clean::TypedStructField(ref ty)) => {
                         try!(write!(w, "    {}{}: {},\n{}",
                                       VisSpace(field.visibility),
                                       field.name.get_ref().as_slice(),
-                                      ty.type_,
+                                      *ty,
                                       tab));
                     }
-                    _ => unreachable!()
-                }
+                    _ => unreachable!(),
+                };
             }
 
             if fields_stripped {
@@ -1499,8 +1516,11 @@ fn render_struct(w: &mut Writer, it: &clean::Item,
                     try!(write!(w, ", "));
                 }
                 match field.inner {
-                    clean::StructFieldItem(ref field) => {
-                        try!(write!(w, "{}", field.type_));
+                    clean::StructFieldItem(clean::HiddenStructField) => {
+                        try!(write!(w, "_"))
+                    }
+                    clean::StructFieldItem(clean::TypedStructField(ref ty)) => {
+                        try!(write!(w, "{}{}", VisSpace(field.visibility), *ty))
                     }
                     _ => unreachable!()
                 }
diff --git a/src/librustdoc/passes.rs b/src/librustdoc/passes.rs
index ed71dc27d9d..9b6d04f2ca4 100644
--- a/src/librustdoc/passes.rs
+++ b/src/librustdoc/passes.rs
@@ -129,12 +129,21 @@ impl<'a> fold::DocFolder for Stripper<'a> {
                 }
             }
 
-            clean::ViewItemItem(..) | clean::StructFieldItem(..) => {
+            clean::ViewItemItem(..) => {
                 if i.visibility != Some(ast::Public) {
                     return None
                 }
             }
 
+            clean::StructFieldItem(..) => {
+                if i.visibility != Some(ast::Public) {
+                    return Some(clean::Item {
+                        inner: clean::StructFieldItem(clean::HiddenStructField),
+                        ..i
+                    })
+                }
+            }
+
             // handled below
             clean::ModuleItem(..) => {}