Update the analysis server diagnostic page - re-enable code completion and overlay pages,

pkg/analysis_server/lib/src/status/pages.dart

+// Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:convert';
+import 'dart:io';
+
+/// Contains a collection of Pages.
+abstract class Site {
+  final String title;
+  List<Page> pages = [];
+
+  Site(this.title);
+
+  String get customCss => '';
+
+  void handleGetRequest(HttpRequest request) {
+    try {
+      String path = request.uri.path;
+
+      if (path == '/') {
+        respondRedirect(request, pages.first.path);
+        return;
+      }
+
+      for (Page page in pages) {
+        if (page.path == path) {
+          HttpResponse response = request.response;
+          response.headers.contentType = ContentType.HTML;
+          response.write(page.generate(request.uri.queryParameters));
+          response.close();
+          return;
+        }
+      }
+
+      respond(request, createUnknownPage(path), HttpStatus.NOT_FOUND);
+    } catch (e, st) {
+      try {
+        respond(request, createExceptionPage('$e', st),
+            HttpStatus.INTERNAL_SERVER_ERROR);
+      } catch (e, st) {
+        HttpResponse response = request.response;
+        response.statusCode = HttpStatus.INTERNAL_SERVER_ERROR;
+        response.headers.contentType = ContentType.TEXT;
+        response.write('$e\n\n$st');
+        response.close();
+      }
+    }
+  }
+
+  Page createUnknownPage(String unknownPath);
+
+  Page createExceptionPage(String message, StackTrace trace);
+
+  void respond(HttpRequest request, Page page, [int code = HttpStatus.OK]) {
+    HttpResponse response = request.response;
+    response.statusCode = code;
+    response.headers.contentType = ContentType.HTML;
+    response.write(page.generate(request.uri.queryParameters));
+    response.close();
+  }
+
+  void respondRedirect(HttpRequest request, String pathFragment) {
+    HttpResponse response = request.response;
+    response.statusCode = HttpStatus.MOVED_TEMPORARILY;
+    response.redirect(request.uri.resolve(pathFragment));
+  }
+}
+
+/// An entity that knows how to serve itself over http.
+abstract class Page {
+  final StringBuffer buf = new StringBuffer();
+
+  final String id;
+  final String title;
+  final String description;
+
+  Page(this.id, this.title, {this.description});
+
+  String get path => '/$id';
+
+  String generate(Map<String, String> params) {
+    buf.clear();
+    generatePage(params);
+    return buf.toString();
+  }
+
+  void generatePage(Map<String, String> params);
+
+  void h1(String text, {String classes}) {
+    if (classes != null) {
+      buf.writeln('<h1 class="$classes">${escape(text)}</h1>');
+    } else {
+      buf.writeln('<h1>${escape(text)}</h1>');
+    }
+  }
+
+  void h2(String text) {
+    buf.writeln('<h2>${escape(text)}</h2>');
+  }
+
+  void h3(String text, {bool raw: false}) {
+    buf.writeln('<h3>${raw ? text : escape(text)}</h3>');
+  }
+
+  void h4(String text, {bool raw: false}) {
+    buf.writeln('<h4>${raw ? text : escape(text)}</h4>');
+  }
+
+  void ul<T>(Iterable<T> items, void gen(T item)) {
+    buf.writeln('<ul>');
+    for (T item in items) {
+      buf.write('<li>');
+      gen(item);
+      buf.write('</li>');
+    }
+    buf.writeln('</ul>');
+  }
+
+  void inputList<T>(Iterable<T> items, void gen(T item)) {
+    buf.writeln('<select size="8" style="width: 100%">');
+    for (T item in items) {
+      buf.write('<option>');
+      gen(item);
+      buf.write('</option>');
+    }
+    buf.writeln('</select>');
+  }
+
+  void div(void gen(), {String classes}) {
+    if (classes != null) {
+      buf.writeln('<div class="$classes">');
+    } else {
+      buf.writeln('<div>');
+    }
+    gen();
+    buf.writeln('</div>');
+  }
+
+  void p(String text, {String style, bool raw: false, String classes}) {
+    String c = classes == null ? '' : ' class="$classes"';
+
+    if (style != null) {
+      buf.writeln('<p$c style="$style">${raw ? text : escape(text)}</p>');
+    } else {
+      buf.writeln('<p$c>${raw ? text : escape(text)}</p>');
+    }
+  }
+
+  void blankslate(String str) {
+    div(() => buf.writeln(str), classes: 'blankslate');
+  }
+
+  bool isCurrentPage(String pathToTest) => path == pathToTest;
+}
+
+String escape(String text) => text == null ? '' : HTML_ESCAPE.convert(text);
+
+String printInteger(int value) {
+  return value.toString();
+}
+
+String printMilliseconds(num value) {
+  return '${value.toStringAsFixed(1)} ms';
+}
+
+String printPercentage(num value) {
+  return '${(value * 100).toStringAsFixed(1)}%';
+}