Wrap notebook contents in a <div class="jp-Notebook"> (#14)

* Added CSS classes for code cells in in wrapper.go
This removes the need for custom renderers to do that on their own

* fix error while printing diffs when comparing HTML structure in tests

* refactor: close HTML tags automatically

pkg/test/render.go

@@ -17,6 +17,7 @@ type fakeWrapper struct{}
 var _ render.CellWrapper = (*fakeWrapper)(nil)
 
 func (*fakeWrapper) RegisterFuncs(render.RenderCellFuncRegistry)                    {}
+func (*fakeWrapper) WrapAll(io.Writer, func(io.Writer) error) error                 { return nil }
 func (*fakeWrapper) Wrap(w io.Writer, c schema.Cell, r render.RenderCellFunc) error { return r(w, c) }
 func (*fakeWrapper) WrapInput(w io.Writer, c schema.Cell, r render.RenderCellFunc) error {
 	return r(w, c)

render/html/html.go

@@ -15,10 +15,10 @@ type Config struct {
 
 type Option func(*Config)
 
-// WithCSSWriter
+// WithCSSWriter registers a writer for CSS stylesheet.
 func WithCSSWriter(w io.Writer) Option {
 	return func(c *Config) {
-		c.CSSWriter = &WriterOnce{w: w}
+		c.CSSWriter = w
 	}
 }
 
@@ -77,18 +77,12 @@ func (r *Renderer) renderCode(w io.Writer, cell schema.Cell) error {
 		return nil
 	}
 
-	div.Open(w, attributes{"class": {"cm-editor", "cm-s-jupyter"}}, true)
-	div.Open(w, attributes{"class": {"highlight", "hl-ipython3"}}, true)
-
 	io.WriteString(w, "<pre><code class=\"language-") // TODO: not sure if that's useful here
 	io.WriteString(w, code.Language())
 	io.WriteString(w, "\">")
 	w.Write(code.Text())
 	io.WriteString(w, "</code></pre>")
 
-	div.Close(w)
-	div.Close(w)
-
 	return nil
 }
 

render/html/html_test.go

@@ -66,6 +66,13 @@ func TestRenderer(t *testing.T) {
 					"src": {"data:image/jpeg;base64, base64-encoded-image"},
 				}},
 			},
+			{
+				name: "image/svg+xml",
+				cell: test.DisplayData("svg-image", "image/svg+xml"),
+				want: &node{tag: "img", attr: map[string][]string{
+					"src": {"data:image/svg+xml;base64, svg-image"},
+				}},
+			},
 			{
 				name: "code cell",
 				cell: &test.CodeCell{
@@ -76,29 +83,14 @@ func TestRenderer(t *testing.T) {
 					Lang: "python",
 				},
 				want: &node{
-					tag: "div",
-					attr: map[string][]string{
-						"class": {"cm-editor", "cm-s-jupyter"},
-					},
+					tag: "pre",
 					children: []*node{
 						{
-							tag: "div",
+							tag: "code",
 							attr: map[string][]string{
-								"class": {"highlight"},
-							},
-							children: []*node{
-								{
-									tag: "pre",
-									children: []*node{
-										{
-											tag: "code",
-											attr: map[string][]string{
-												"class": {"language-python"},
-											},
-											content: "print('Hi, mom!')",
-										},
-									}},
+								"class": {"language-python"},
 							},
+							content: "print('Hi, mom!')",
 						},
 					},
 				},
@@ -123,20 +115,6 @@ func TestRenderer(t *testing.T) {
 }
 
 func TestRenderer_CSSWriter(t *testing.T) {
-	t.Run("WithCSSWriter wraps in WriterOnce", func(t *testing.T) {
-		// Arrange
-		var cfg html.Config
-		opt := html.WithCSSWriter(io.Discard)
-
-		// Act
-		opt(&cfg)
-
-		// Assert
-		if _, ok := cfg.CSSWriter.(*html.WriterOnce); !ok {
-			t.Errorf("expected *html.WriterOnce, got %T", cfg.CSSWriter)
-		}
-	})
-
 	t.Run("captures correct css", func(t *testing.T) {
 		// Arrange
 		var css bytes.Buffer
@@ -149,7 +127,7 @@ func TestRenderer_CSSWriter(t *testing.T) {
 		}
 
 		// Act
-		err = r.Wrap(io.Discard, test.Markdown(""), noopRender)
+		err = r.WrapAll(io.Discard, func(w io.Writer) error { return nil })
 		require.NoError(t, err)
 
 		// Assert