Reducing the amount of code we generate in the compiler: We still continue

lib/src/emitters.dart

Index: lib/src/emitters.dart
diff --git a/lib/src/emitters.dart b/lib/src/emitters.dart
index a7de9c2d0c21eb91c52b10352db7887769f17f16..34d0d8686780a4d2537c7f7e9ba5c4c940c6866e 100644
--- a/lib/src/emitters.dart
+++ b/lib/src/emitters.dart
@@ -12,35 +12,18 @@ import 'package:html5lib/dom_parsing.dart';
 import 'package:html5lib/parser.dart';
 import 'package:source_maps/span.dart' show Span, FileLocation;
 
-import 'compiler.dart';
 import 'code_printer.dart';
+import 'compiler.dart';
 import 'dart_parser.dart' show DartCodeInfo;
-import 'html_css_fixup.dart';
 import 'html5_utils.dart';
+import 'html_css_fixup.dart';
 import 'info.dart';
 import 'messages.dart';
+import 'options.dart';
 import 'paths.dart';
 import 'refactor.dart';
 import 'utils.dart';
 
-/**
- * Context used by an emitter. Typically representing where to generate code
- * and additional information, such as total number of generated identifiers.
- */
-class Context {
-  final Declarations statics;
-  final CodePrinter printer;
-  final bool isClass;
-
-  Context({Declarations statics, CodePrinter printer, bool isClass: false,
-           int indent: 0})
-      : this.statics = statics != null
-            ? statics : new Declarations(indent, staticKeyword: isClass),
-        this.isClass = isClass,
-        this.printer = printer != null
-            ? printer : new CodePrinter(isClass ? indent + 1 : indent);
-}
-
 
 /** Only x-tag name element selectors are emitted as [is="x-"]. */
 class CssEmitter extends CssPrinter {
@@ -199,33 +182,15 @@ class WebComponentEmitter {
   final Messages messages;
   final FileInfo _fileInfo;
   final CssPolyfillKind cssPolyfillKind;
-  Context _context;
 
-  WebComponentEmitter(this._fileInfo, this.messages, this.cssPolyfillKind)
-      : _context = new Context(isClass: true, indent: 1);
+  WebComponentEmitter(this._fileInfo, this.messages, this.cssPolyfillKind);
 
   CodePrinter run(ComponentInfo info, PathMapper pathMapper,
       TextEditTransaction transaction) {
-    var templateNode = info.elementNode;
-
-    // elementNode is pointing at template tag (no attributes).
-    assert(templateNode.tagName == 'element');
-    for (var node in templateNode.nodes) {
-      if (node.tagName == 'template') {
-        templateNode = node;
-        break;
-      }
-    }
+    var templateNode = info.element.nodes.firstWhere(
+        (n) => n.tagName == 'template', orElse: () => null);
 
-    if (info.element.attributes['apply-author-styles'] != null) {
-      _context.printer.addLine('if (__root is autogenerated.ShadowRoot) '
-          '__root.applyAuthorStyles = true;');
-      // TODO(jmesserly): warn at runtime if apply-author-styles was not set,
-      // and we don't have Shadow DOM support? In that case, styles won't have
-      // proper encapsulation.
-    }
-
-    if (templateNode.tagName == 'template') {
+    if (templateNode != null) {
       if (!info.styleSheets.isEmpty && !messages.options.processCss) {
         // TODO(terry): Only one style tag per component.
 
@@ -240,24 +205,6 @@ class WebComponentEmitter {
             new Element.html('<style>\n$styleText\n</style>'),
             templateNode.hasChildNodes() ? templateNode.children[0] : null);
       }
-
-      _context.statics.add('final', '__shadowTemplate',
-          templateNode.sourceSpan,
-          "new autogenerated.DocumentFragment.html('''"
-          "${escapeDartString(templateNode.innerHtml, triple: true)}"
-          "''')");
-
-      var syntax = templateNode.attributes['syntax'];
-      if (syntax != null) {
-        syntax = escapeDartString(syntax);
-        syntax = ", autogenerated.TemplateElement.syntax['$syntax']";
-      } else {
-        syntax = "";
-      }
-
-      _context.printer
-          ..addLine("__root.nodes.add(cloneTemplate(__shadowTemplate));")
-          ..addLine("autogenerated_mdv.bindModel(__root, this$syntax);");
     }
 
     bool hasExtends = info.extendsComponent != null;
@@ -281,30 +228,8 @@ class WebComponentEmitter {
     header.addLine('');
     transaction.edit(0, codeInfo.directivesEnd, header);
 
-    var mangle = cssPolyfillKind == CssPolyfillKind.MANGLED_POLYFILL;
-    var cssMapExpression = createCssSelectorsExpression(info, mangle);
     var classBody = new CodePrinter(1)
         ..add('\n')
-        ..addLine('/** Autogenerated from the template. */')
-        ..addLine('')
-        // TODO(terry): Remove [_css]; after migrating to getScopedCss.
-        ..addLine('autogenerated.ScopedCssMapper _css;')
-        ..addLine('')
-        ..addLine('/** This field is deprecated, use getShadowRoot instead. */')
-        ..addLine('get _root => getShadowRoot("${info.tagName}");')
-        ..add(_context.statics)
-        ..addLine('')
-        ..addLine('void initShadow() {')
-        ..addLine(hasExtends ? '  super.initShadow();' : null)
-        ..addLine('  var __root = createShadowRoot("${info.tagName}");')
-        ..addLine('  shadowRootReady(__root, "${info.tagName}");')
-        ..addLine('  setScopedCss("${info.tagName}", '
-            'new autogenerated.ScopedCssMapper($cssMapExpression));')
-        // TODO(terry): Remove assignment after migrating to getScopedCss.
-        ..addLine('  _css = getScopedCss("${info.tagName}");')
-        ..add(_context.printer)
-        ..addLine('}')
-        ..addLine('')
         ..addLine('/** Original code from the component. */');
 
     var pos = classDecl.leftBracket.end;
@@ -315,63 +240,50 @@ class WebComponentEmitter {
   }
 }
 
-/** Generates the class corresponding to the main html page. */
-class EntryPointEmitter {
-  final GlobalInfo global;
-  final FileInfo _fileInfo;
-  Context _context;
-
-  EntryPointEmitter(this._fileInfo, this.global)
-      : _context = new Context(indent: 1);
+/** The code that will be used to bootstrap the application. */
+CodePrinter generateBootstrapCode(
+    FileInfo info, FileInfo userMainInfo, GlobalInfo global,
+    PathMapper pathMapper, CompilerOptions options) {
 
-  CodePrinter run(PathMapper pathMapper, TextEditTransaction transaction,
-      bool rewriteUrls) {
+  var printer = new CodePrinter(0)
+      ..addLine('library app_bootstrap;')
+      ..addLine('')
+      ..addLine("import 'package:polymer/polymer.dart' as polymer;");
 
-    var filePath = _fileInfo.inputUrl.resolvedPath;
-
-    var codeInfo = _fileInfo.userCode;
-    if (codeInfo == null) {
-      assert(transaction == null);
-      codeInfo = new DartCodeInfo(null, null, [], 'main(){\n}', null);
-    }
-
-    if (transaction == null) {
-      transaction = new TextEditTransaction(codeInfo.code, codeInfo.sourceFile);
-    }
+  if (userMainInfo.userCode != null) {
+    printer..addLine('')
+        ..addLine("import '${pathMapper.importUrlFor(info, userMainInfo)}' "
+            "as userMain;\n");
+  }
 
-    var libraryName = codeInfo.libraryName != null
-        ? codeInfo.libraryName : _fileInfo.libraryName;
-    var header = new CodePrinter(0);
-    header.add(_header(path.basename(filePath), libraryName));
-    emitImports(codeInfo, _fileInfo, pathMapper, header, global);
-    header..addLine('')
-          ..addLine('')
-          ..addLine('// Original code');
-    transaction.edit(0, codeInfo.directivesEnd, header);
+  for (var c in global.components.values) {
+    if (c.hasConflict) continue;
+    printer.addLine("import '${pathMapper.importUrlFor(info, c)}';");
+  }
 
-    var printer = (transaction.commit())
-        ..addLine('')
-        ..addLine('// Additional generated code')
-        ..addLine('void init_autogenerated() {')
-        ..indent += 1;
+  printer..addLine('')
+      ..addLine('void main() {')
+      ..indent += 1;
+
+  if (userMainInfo.userCode != null) printer.addLine('userMain.main();');
+
+  for (var c in global.components.values) {
+    if (c.hasConflict) continue;
+    var tagName = escapeDartString(c.tagName);
+    var cssMapExpression = createCssSelectorsExpression(c,
+        CssPolyfillKind.of(options, c));
+    printer
+        ..addLine("polymer.setScopedCss('$tagName', $cssMapExpression);")
+        ..addLine("polymer.registerPolymerElement("
+            "'$tagName', () => new ${c.className}());");
+  }
 
-    for (var c in global.components.values) {
-      if (c.hasConflict) continue;
-      var tagName = escapeDartString(c.tagName);
+  return printer
+      ..indent -= 1
+      ..addLine('}');
+}
 
-      printer.addLine("autogenerated.registerPolymerElement("
-        "new autogenerated.Element.html("
-            "'${escapeDartString(c.elementNode.outerHtml)}')"
-        ", () => new ${c.className}());");
-    }
 
-    return printer
-        ..add(_context.statics)
-        ..add(_context.printer)
-        ..indent -= 1
-        ..addLine('}');
-  }
-}
 
 /**
  * List of HTML4 elements which could have relative URL resource:
@@ -451,7 +363,8 @@ final shadowDomJS = new RegExp(r'shadowdom\..*\.js', caseSensitive: false);
 
 /** Trim down the html for the main html page. */
 void transformMainHtml(Document document, FileInfo fileInfo,
-    PathMapper pathMapper, bool hasCss, bool rewriteUrls, Messages messages) {
+    PathMapper pathMapper, bool hasCss, bool rewriteUrls,
+    Messages messages, GlobalInfo global) {
   var filePath = fileInfo.inputUrl.resolvedPath;
 
   bool dartLoaderFound = false;
@@ -472,6 +385,7 @@ void transformMainHtml(Document document, FileInfo fileInfo,
       tag.attributes["src"] = pathMapper.transformUrl(filePath, src);
     }
   }
+
   for (var tag in document.queryAll('link')) {
     var href = tag.attributes['href'];
     var rel = tag.attributes['rel'];
@@ -512,6 +426,21 @@ void transformMainHtml(Document document, FileInfo fileInfo,
   document.head.nodes.insert(0, parseFragment(
       '<style>template { display: none; }</style>'));
 
+  // Move all <element> declarations to the main HTML file
+  // TODO(sigmund): remove this once we have HTMLImports implemented.
+  for (var c in global.components.values) {
+    document.body.nodes.insert(0, new Text('\n'));
+    var fragment = c.element;
+    for (var tag in fragment.queryAll('script')) {
+      // TODO(sigmund): leave script tags around when we start using "boot.js"
+      if (tag.attributes['type'] == 'application/dart') {
+        tag.remove();
+      }
+    }
+    document.body.nodes.insert(0, fragment);
+  }
+
+
   if (!shadowDomFound) {
     // TODO(jmesserly): we probably shouldn't add this automatically.
     document.body.nodes.add(parseFragment('<script type="text/javascript" '
@@ -522,6 +451,7 @@ void transformMainHtml(Document document, FileInfo fileInfo,
     //messages.warning('Missing script to load Dart. '
     //    'Please add this line to your HTML file: $dartLoader',
     //    document.body.sourceSpan);
+    // TODO(sigmund): switch to 'boot.js'
     document.body.nodes.add(parseFragment('<script type="text/javascript" '
         'src="packages/browser/dart.js"></script>\n'));
   }