empty test page

package chromedp import ( "context" "fmt" "net/http" "net/http/httptest" "strconv" "testing" "time" "github.com/chromedp/cdproto/cdp" "github.com/chromedp/cdproto/runtime" ) // dumpJS is a JavaScript snippet that dumps the passed element node in the // same text format as cdproto/cdp/Node.Dump. // // Used to verify that the DOM tree built by chromedp is the same as what // chrome itself sees. // // Note: written to be "line-by-line equivalent" with Node.Dump's // implementation. const dumpJS = `(function dump(n, prefix, indent, nodeIDs) { if (n === null || typeof n !== 'object') { return prefix + ''; } var s = ''; if (typeof n.localName !== 'undefined') { s = n.localName; } if (s === '' && typeof n.nodeName !== 'undefined') { s = n.nodeName; } if (s === '') { throw 'invalid node element'; } if (typeof n.attributes !== 'undefined') { for (var i = 0; i < n.attributes.length; i++) { if (n.attributes[i].name.toLowerCase() === 'id') { s += '#' + n.attributes[i].value; break; } } } if (n.nodeType !== 1 && n.nodeType !== 3) { s += ' <' + [ 'Element', 'Attribute', 'Text', 'CDATA', 'EntityReference', 'Entity', 'ProcessingInstruction', 'Comment', 'Document', 'DocumentType', 'DocumentFragment', 'Notation' ][n.nodeType - 1] + '>'; } if (n.nodeType === 3) { var v = n.nodeValue; if (v.length > 15) { v = v.substring(0, 15) + '...'; } s += ' ' + JSON.stringify(v); } if (n.nodeType === 1 && typeof n.attributes !== 'undefined' && n.attributes.length > 0) { var attrs = ''; for (var i = 0; i < n.attributes.length; i++) { if (n.attributes[i].name.toLowerCase() === 'id') { continue; } if (attrs !== '') { attrs += ' '; } attrs += n.attributes[i].name + '=' + JSON.stringify(n.attributes[i].value); } if (attrs != '') { s += ' [' + attrs + ']'; } } if (nodeIDs) { throw 'cannot read element node ID from scripts'; } if (typeof n.childNodes !== 'undefined' && n.childNodes.length > 0) { for (var i = 0; i < n.childNodes.length; i++) { // skip empty #text nodes if (n.childNodes[i].nodeType === 3 && n.childNodes[i].nodeValue.trim() === '') { continue; } s += '\n' + dump(n.childNodes[i], prefix+indent, indent, nodeIDs); } } return prefix + s; })(%s, %q, %q, %t);` const insertJS = `(function(n, typ, id, text) { var el = document.createElement(typ); el.id = id; el.innerText = text; %s; })(document.querySelector(%q), %q, %q, %q)` // test: // - insertBefore // - removeChild // - appendChild // - replaceChild // - prepend // - append // - insertAdjacentElement func TestNodeOp(t *testing.T) { t.Parallel() s := httptest.NewServer(http.HandlerFunc(func(res http.ResponseWriter, req *http.Request) { fmt.Fprintf(res, ` empty test page

div1 content

`) })) defer s.Close() ctx, cancel := testAllocate(t, "") defer cancel() // get document root var nodes []*cdp.Node if err := Run(ctx, Navigate(s.URL), Nodes(`//*`, &nodes), Nodes(`document`, &nodes, ByJSPath), ); err != nil { t.Fatal(err) } tests := []struct { q, expr string }{ {`body`, `n.insertBefore(el, n.childNodes[0])`}, {`body`, `n.insertBefore(el, n.childNodes[1])`}, {`#div3`, `n.prepend(el)`}, {`#div2`, `n.append(el)`}, {`#div2`, `n.appendChild(el)`}, {`#div3`, `n.removeChild(n.childNodes[0])`}, {`#div2`, `n.insertAdjacentElement('afterend', el)`}, {`body`, `n.insertBefore(el, n.childNodes[0])`}, {`body`, `n.insertBefore(el, n.childNodes[1])`}, {`#div2`, `n.replaceChild(el, n.childNodes[1])`}, } prev := nodes[0].Dump("", " ", false) for i, test := range tests { // modify tree if err := Run(ctx, ActionFunc(func(ctx context.Context) error { id := strconv.Itoa(i + 2) expr := fmt.Sprintf(insertJS, test.expr, test.q, `div`, `div`+id, `div`+id+` content`) _, exp, err := runtime.Evaluate(expr).Do(ctx) if err != nil { return err } if exp != nil { return exp } return nil }), ); err != nil { t.Fatal(err) } // wait for events to propagate time.Sleep(5 * time.Millisecond) tree := nodes[0].Dump("", " ", false) if prev == tree { t.Fatalf("test %d expected tree to change (prev == tree)\n-- PREV:\n%s\n-- TREE:\n%s\n--\n", i, prev, tree) } // retrieve browser's tree view var exp string if err := Run(ctx, EvaluateAsDevTools(fmt.Sprintf(dumpJS, `document`, "", " ", false), &exp), ); err != nil { t.Fatal(err) } if exp != tree { t.Errorf("test %d expected tree and node tree do not match:\n-- EXPECTED:\n%s\n-- GOT:\n%s\n--\n", i, exp, tree) } prev = tree // t.Logf("test %d:\n%s\n--\n", i, tree) } }