Show packages and libraries in the breadcrumbs

This makes the breadcrumbs more readable by removing unteresting
components and make the beginning of the module path more recognizable.

src/html/generator.ml

@@ -14,6 +14,7 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  *)
 
+open Odoc_utils
 open Odoc_document.Types
 module Html = Tyxml.Html
 module Doctree = Odoc_document.Doctree
@@ -455,23 +456,27 @@ module Breadcrumbs = struct
   open Types
 
   let gen_breadcrumbs ~config ~url =
-    let rec get_parent_paths x =
-      match x with
-      | [] -> []
-      | x :: xs -> (
-          match Odoc_document.Url.Path.of_list (List.rev (x :: xs)) with
-          | Some x -> x :: get_parent_paths xs
-          | None -> get_parent_paths xs)
+    let resolve = Link.Current url in
+    let breadcrumb ?(prefix = "") url =
+      let href = Link.href ~config ~resolve (Url.from_path url) in
+      { href; name = prefix ^ url.name; kind = url.kind }
     in
-    let to_breadcrumb path =
-      let href =
-        Link.href ~config ~resolve:(Current url)
-          (Odoc_document.Url.from_path path)
-      in
-      { href; name = path.name; kind = path.kind }
+    let rec package url =
+      match url.Url.Path.parent with
+      | None -> breadcrumb ~prefix:"Package " url
+      | Some url -> package url
+    in
+    let rec rhs (url : Url.Path.t) =
+      match url with
+      | { kind = `Library; parent; _ } ->
+          let package = Option.map package parent in
+          (* Don't list components that separates the package and library names. *)
+          breadcrumb ~prefix:"Library " url :: Option.to_list package
+      | { parent = None; kind = `Page; _ } -> [ package url ]
+      | { parent = None; _ } -> [ breadcrumb url ]
+      | { parent = Some parent; _ } -> breadcrumb url :: rhs parent
     in
-    get_parent_paths (List.rev (Odoc_document.Url.Path.to_list url))
-    |> List.rev |> List.map to_breadcrumb
+    List.rev (rhs url)
 end
 
 module Page = struct

test/integration/html_opts.t/run.t

@@ -22,7 +22,7 @@ Generate --as-json embeddable HTML fragment output:
 
   $ odoc html-generate test.odocl -o html --as-json --indent
   $ cat html/test/Test/index.html.json
-  {"type":"documentation","uses_katex":false,"breadcrumbs":[{"name":"test","href":"../index.html","kind":"library"},{"name":"Test","href":"#","kind":"module"}],"toc":[{"title":"Section 1","href":"#section-1","children":[]},{"title":"Section 2","href":"#section-2","children":[]}],"global_toc":null,"source_anchor":null,"preamble":"<p>Test</p>","content":"<h2 id=\"section-1\"><a href=\"#section-1\" class=\"anchor\"></a>Section 1</h2><div class=\"odoc-spec\">\u000A <div class=\"spec type anchored\" id=\"type-t\">\u000A  <a href=\"#type-t\" class=\"anchor\"></a>\u000A  <code><span><span class=\"keyword\">type</span> t</span></code>\u000A </div>\u000A</div><h2 id=\"section-2\"><a href=\"#section-2\" class=\"anchor\"></a>Section 2</h2><div class=\"odoc-spec\">\u000A <div class=\"spec type anchored\" id=\"type-u\">\u000A  <a href=\"#type-u\" class=\"anchor\"></a>\u000A  <code><span><span class=\"keyword\">type</span> u</span></code>\u000A </div>\u000A</div>"}
+  {"type":"documentation","uses_katex":false,"breadcrumbs":[{"name":"Library test","href":"../index.html","kind":"library"},{"name":"Test","href":"#","kind":"module"}],"toc":[{"title":"Section 1","href":"#section-1","children":[]},{"title":"Section 2","href":"#section-2","children":[]}],"global_toc":null,"source_anchor":null,"preamble":"<p>Test</p>","content":"<h2 id=\"section-1\"><a href=\"#section-1\" class=\"anchor\"></a>Section 1</h2><div class=\"odoc-spec\">\u000A <div class=\"spec type anchored\" id=\"type-t\">\u000A  <a href=\"#type-t\" class=\"anchor\"></a>\u000A  <code><span><span class=\"keyword\">type</span> t</span></code>\u000A </div>\u000A</div><h2 id=\"section-2\"><a href=\"#section-2\" class=\"anchor\"></a>Section 2</h2><div class=\"odoc-spec\">\u000A <div class=\"spec type anchored\" id=\"type-u\">\u000A  <a href=\"#type-u\" class=\"anchor\"></a>\u000A  <code><span><span class=\"keyword\">type</span> u</span></code>\u000A </div>\u000A</div>"}
 
   $ odoc html-targets test.odocl -o html --as-json --indent
   html/test/Test/index.html.json

test/integration/json_expansion_with_sources.t/run.t

@@ -47,4 +47,4 @@ Test the JSON output in the presence of expanded modules.
   {"type":"documentation","uses_katex":false,"breadcrumbs":[{"name":"Main","href":"../../index.html","kind":"module"},{"name":"A","href":"../index.html","kind":"module"},{"name":"B","href":"#","kind":"module"}],"toc":[],"global_toc":null,"source_anchor":"../../../src/a.ml.html#module-B","preamble":"","content":""}
 
   $ cat html/src/a.ml.html.json
-  {"type":"source","breadcrumbs":[{"name":"src","href":"index.html","kind":"page"},{"name":"a.ml","href":"#","kind":"source"}],"content":"<pre class=\"source_container\"><code class=\"source_line_column\"><a id=\"L1\" class=\"source_line\" href=\"#L1\">1</a>\u000A</code><code class=\"source_code\"><span><span id=\"module-B\"><span class=\"MODULE\">module</span> <span class=\"UIDENT\">B</span> <span class=\"EQUAL\">=</span> <span class=\"STRUCT\">struct</span> <span class=\"END\">end</span></span><span class=\"EOL\">\u000A</span></span></code></pre>"}
+  {"type":"source","breadcrumbs":[{"name":"Package src","href":"index.html","kind":"page"},{"name":"a.ml","href":"#","kind":"source"}],"content":"<pre class=\"source_container\"><code class=\"source_line_column\"><a id=\"L1\" class=\"source_line\" href=\"#L1\">1</a>\u000A</code><code class=\"source_code\"><span><span id=\"module-B\"><span class=\"MODULE\">module</span> <span class=\"UIDENT\">B</span> <span class=\"EQUAL\">=</span> <span class=\"STRUCT\">struct</span> <span class=\"END\">end</span></span><span class=\"EOL\">\u000A</span></span></code></pre>"}

test/model/index_page_name.t/run.t

@@ -13,4 +13,4 @@ The breadcrumbs shouldn't show the name of the page, "index".
 Expected to fail:
 
   $ grep odoc-nav test/index.html
-    <nav class="odoc-nav"><a href="../index.html">Up</a> – test</nav>
+    <nav class="odoc-nav"><a href="../index.html">Up</a> – Package test</nav>

test/xref2/include_module_type_of_preamble.t/run.t

@@ -16,7 +16,7 @@ Foo contains "Preamble for O" once.
    </head>
    <body class="odoc">
     <nav class="odoc-nav"><a href="../index.html">Up</a> – 
-     <a href="../index.html">test</a> &#x00BB; Foo
+     <a href="../index.html">Library test</a> &#x00BB; Foo
     </nav>
     <header class="odoc-preamble"><h1>Module <code><span>Foo</span></code></h1>
      <p>Preamble for Foo.</p>
@@ -59,7 +59,7 @@ Bar doesn't contain "Preamble for Foo" on purpose.
    </head>
    <body class="odoc">
     <nav class="odoc-nav"><a href="../index.html">Up</a> – 
-     <a href="../index.html">test</a> &#x00BB; Bar
+     <a href="../index.html">Library test</a> &#x00BB; Bar
     </nav>
     <header class="odoc-preamble"><h1>Module <code><span>Bar</span></code></h1>
     </header>
@@ -134,7 +134,7 @@ Check the preambles:
    </head>
    <body class="odoc">
     <nav class="odoc-nav"><a href="../index.html">Up</a> – 
-     <a href="../../index.html">test</a> &#x00BB; 
+     <a href="../../index.html">Library test</a> &#x00BB; 
      <a href="../index.html">Bar</a> &#x00BB; Q
     </nav>
     <header class="odoc-preamble">
@@ -155,7 +155,7 @@ Check the preambles:
    </head>
    <body class="odoc">
     <nav class="odoc-nav"><a href="../index.html">Up</a> – 
-     <a href="../../index.html">test</a> &#x00BB; 
+     <a href="../../index.html">Library test</a> &#x00BB; 
      <a href="../index.html">Bar</a> &#x00BB; P
     </nav>
     <header class="odoc-preamble">

test/xref2/labels/labels.t/run.t

@@ -52,7 +52,7 @@ There are two references in N, one should point to a local label and the other t
    </head>
    <body class="odoc">
     <nav class="odoc-nav"><a href="../index.html">Up</a> – 
-     <a href="../../index.html">test</a> &#x00BB; 
+     <a href="../../index.html">Library test</a> &#x00BB; 
      <a href="../index.html">Test</a> &#x00BB; N
     </nav>
     <header class="odoc-preamble">
@@ -87,7 +87,7 @@ The second occurence of 'B' in the main page should be disambiguated
    </head>
    <body class="odoc">
     <nav class="odoc-nav"><a href="../index.html">Up</a> – 
-     <a href="../index.html">test</a> &#x00BB; Test
+     <a href="../index.html">Library test</a> &#x00BB; Test
     </nav>
     <header class="odoc-preamble">
      <h1>Module <code><span>Test</span></code></h1>

test/xref2/module_preamble.t/run.t

@@ -40,7 +40,7 @@ and that "hidden" modules (eg. `A__b`, rendered to `html/A__b`) are not rendered
    </head>
    <body class="odoc">
     <nav class="odoc-nav"><a href="../index.html">Up</a> – 
-     <a href="../index.html">test</a> &#x00BB; A
+     <a href="../index.html">Library test</a> &#x00BB; A
     </nav>
     <header class="odoc-preamble"><h1>Module <code><span>A</span></code></h1>
      <p>Module A.</p>
@@ -78,8 +78,8 @@ and that "hidden" modules (eg. `A__b`, rendered to `html/A__b`) are not rendered
    </head>
    <body class="odoc">
     <nav class="odoc-nav"><a href="../index.html">Up</a> – 
-     <a href="../../index.html">test</a> &#x00BB; <a href="../index.html">A</a>
-      &#x00BB; B
+     <a href="../../index.html">Library test</a> &#x00BB; 
+     <a href="../index.html">A</a> &#x00BB; B
     </nav>
     <header class="odoc-preamble"><h1>Module <code><span>A.B</span></code></h1>
      <p>Module B. This paragraph is the synopsis.</p>
@@ -120,7 +120,7 @@ and that "hidden" modules (eg. `A__b`, rendered to `html/A__b`) are not rendered
    </head>
    <body class="odoc">
     <nav class="odoc-nav"><a href="../index.html">Up</a> – 
-     <a href="../index.html">test</a> &#x00BB; A__b
+     <a href="../index.html">Library test</a> &#x00BB; A__b
     </nav>
     <header class="odoc-preamble">
      <h1>Module <code><span>A__b</span></code></h1>