Replace boolean argument for print_where_clause with an enum to make code more clear

src/librustdoc/html/format.rs

@@ -268,14 +268,20 @@ impl clean::Generics {
     }
 }
 
+#[derive(Clone, Copy, PartialEq, Eq)]
+pub(crate) enum Ending {
+    Newline,
+    NoNewline,
+}
+
 /// * The Generics from which to emit a where-clause.
 /// * The number of spaces to indent each line with.
 /// * Whether the where-clause needs to add a comma and newline after the last bound.
 pub(crate) fn print_where_clause<'a, 'tcx: 'a>(
     gens: &'a clean::Generics,
     cx: &'a Context<'tcx>,
     indent: usize,
-    end_newline: bool,
+    ending: Ending,
 ) -> impl fmt::Display + 'a + Captures<'tcx> {
     use fmt::Write;
 
@@ -342,7 +348,7 @@ pub(crate) fn print_where_clause<'a, 'tcx: 'a>(
 
         let where_preds = comma_sep(where_predicates, false);
         let clause = if f.alternate() {
-            if end_newline {
+            if ending == Ending::Newline {
                 // add a space so stripping <br> tags and breaking spaces still renders properly
                 format!(" where{where_preds}, ")
             } else {
@@ -356,7 +362,7 @@ pub(crate) fn print_where_clause<'a, 'tcx: 'a>(
             }
             let where_preds = where_preds.to_string().replace("<br>", &br_with_padding);
 
-            if end_newline {
+            if ending == Ending::Newline {
                 let mut clause = "&nbsp;".repeat(indent.saturating_sub(1));
                 // add a space so stripping <br> tags and breaking spaces still renders properly
                 write!(
@@ -1167,7 +1173,7 @@ impl clean::Impl {
                 fmt_type(&self.for_, f, use_absolute, cx)?;
             }
 
-            fmt::Display::fmt(&print_where_clause(&self.generics, cx, 0, true), f)?;
+            fmt::Display::fmt(&print_where_clause(&self.generics, cx, 0, Ending::Newline), f)?;
             Ok(())
         })
     }

src/librustdoc/html/render/mod.rs

@@ -70,7 +70,7 @@ use crate::formats::{AssocItemRender, Impl, RenderMode};
 use crate::html::escape::Escape;
 use crate::html::format::{
     href, join_with_double_colon, print_abi_with_space, print_constness_with_space,
-    print_default_space, print_generic_bounds, print_where_clause, Buffer, HrefError,
+    print_default_space, print_generic_bounds, print_where_clause, Buffer, Ending, HrefError,
     PrintWithSpace,
 };
 use crate::html::highlight;
@@ -748,7 +748,7 @@ fn assoc_type(
     if !bounds.is_empty() {
         write!(w, ": {}", print_generic_bounds(bounds, cx))
     }
-    write!(w, "{}", print_where_clause(generics, cx, indent, false));
+    write!(w, "{}", print_where_clause(generics, cx, indent, Ending::NoNewline));
     if let Some(default) = default {
         write!(w, " = {}", default.print(cx))
     }
@@ -797,10 +797,10 @@ fn assoc_method(
         header_len += 4;
         let indent_str = "    ";
         render_attributes_in_pre(w, meth, indent_str);
-        (4, indent_str, false)
+        (4, indent_str, Ending::NoNewline)
     } else {
         render_attributes_in_code(w, meth);
-        (0, "", true)
+        (0, "", Ending::Newline)
     };
     w.reserve(header_len + "<a href=\"\" class=\"fnname\">{".len() + "</a>".len());
     write!(

src/librustdoc/html/render/print_item.rs

@@ -29,7 +29,7 @@ use crate::formats::{AssocItemRender, Impl, RenderMode};
 use crate::html::escape::Escape;
 use crate::html::format::{
     join_with_double_colon, print_abi_with_space, print_constness_with_space, print_where_clause,
-    Buffer, PrintWithSpace,
+    Buffer, Ending, PrintWithSpace,
 };
 use crate::html::highlight;
 use crate::html::layout::Page;
@@ -69,7 +69,7 @@ fn print_where_clause_and_check<'a, 'tcx: 'a>(
     cx: &'a Context<'tcx>,
 ) -> bool {
     let len_before = buffer.len();
-    write!(buffer, "{}", print_where_clause(gens, cx, 0, true));
+    write!(buffer, "{}", print_where_clause(gens, cx, 0, Ending::Newline));
     len_before != buffer.len()
 }
 
@@ -519,7 +519,7 @@ fn item_function(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, f: &cle
                 abi = abi,
                 name = name,
                 generics = f.generics.print(cx),
-                where_clause = print_where_clause(&f.generics, cx, 0, true),
+                where_clause = print_where_clause(&f.generics, cx, 0, Ending::Newline),
                 decl = f.decl.full_print(header_len, 0, header.asyncness, cx),
                 notable_traits = notable_traits_decl(&f.decl, cx),
             );
@@ -556,7 +556,7 @@ fn item_trait(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &clean:
             );
 
             if !t.generics.where_predicates.is_empty() {
-                write!(w, "{}", print_where_clause(&t.generics, cx, 0, true));
+                write!(w, "{}", print_where_clause(&t.generics, cx, 0, Ending::Newline));
             } else {
                 w.write_str(" ");
             }
@@ -1026,7 +1026,7 @@ fn item_trait_alias(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &
                 "trait {}{}{} = {};",
                 it.name.unwrap(),
                 t.generics.print(cx),
-                print_where_clause(&t.generics, cx, 0, true),
+                print_where_clause(&t.generics, cx, 0, Ending::Newline),
                 bounds(&t.bounds, true, cx)
             );
         });
@@ -1050,7 +1050,7 @@ fn item_opaque_ty(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &cl
                 "type {}{}{where_clause} = impl {bounds};",
                 it.name.unwrap(),
                 t.generics.print(cx),
-                where_clause = print_where_clause(&t.generics, cx, 0, true),
+                where_clause = print_where_clause(&t.generics, cx, 0, Ending::Newline),
                 bounds = bounds(&t.bounds, false, cx),
             );
         });
@@ -1075,7 +1075,7 @@ fn item_typedef(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &clea
                 "type {}{}{where_clause} = {type_};",
                 it.name.unwrap(),
                 t.generics.print(cx),
-                where_clause = print_where_clause(&t.generics, cx, 0, true),
+                where_clause = print_where_clause(&t.generics, cx, 0, Ending::Newline),
                 type_ = t.type_.print(cx),
             );
         });
@@ -1786,7 +1786,7 @@ fn render_struct(
             }
             w.write_str(")");
             if let Some(g) = g {
-                write!(w, "{}", print_where_clause(g, cx, 0, false));
+                write!(w, "{}", print_where_clause(g, cx, 0, Ending::NoNewline));
             }
             // We only want a ";" when we are displaying a tuple struct, not a variant tuple struct.
             if structhead {
@@ -1796,7 +1796,7 @@ fn render_struct(
         CtorKind::Const => {
             // Needed for PhantomData.
             if let Some(g) = g {
-                write!(w, "{}", print_where_clause(g, cx, 0, false));
+                write!(w, "{}", print_where_clause(g, cx, 0, Ending::NoNewline));
             }
             w.write_str(";");
         }