Build script views programmatically.

runtime/observatory/lib/src/elements/script_inset.dart

Index: runtime/observatory/lib/src/elements/script_inset.dart
diff --git a/runtime/observatory/lib/src/elements/script_inset.dart b/runtime/observatory/lib/src/elements/script_inset.dart
index aef3fe3dde57d321ee2f8a107482a897802cf8a6..d5c4625231618cf147630933054c054794d656a9 100644
--- a/runtime/observatory/lib/src/elements/script_inset.dart
+++ b/runtime/observatory/lib/src/elements/script_inset.dart
@@ -9,6 +9,22 @@ import 'observatory_element.dart';
 import 'package:observatory/service.dart';
 import 'package:polymer/polymer.dart';
 
+const nbsp = "\u00A0";
+
+class Annotation {
+  int line;
+  int columnStart;
+  int columnStop;
+  String title;
+
+  void applyStyleTo(element) {
+    element.style.color = "blue";
+    element.style.textDecoration = "underline";
+    element.title = title;
+    print("Annotated ${element.text} as $title");

[Cutch, 2015/02/27 14:44:33]

Remove before committing.

[rmacnak, 2015/02/27 20:55:34]

Done.

+  }
+}
+
 /// Box with script source code in it.
 @CustomTag('script-inset')
 class ScriptInsetElement extends ObservatoryElement {
@@ -28,91 +44,98 @@ class ScriptInsetElement extends ObservatoryElement {
   @observable int endLine;
   @observable bool linesReady = false;
 
-  // Contents are either ScriptLine or ScriptElipsis.
-  @observable List lines = toObservable([]);
+  var annotations = [];
+  var annotationsCursor;
+
+  StreamSubscription scriptChangeSubscription;
 
   String makeLineId(int line) {
     return 'line-$line';
   }
 
-  String clip(String line, int start, [int limit]) {
-    try {
-      return line.substring(start, limit);
-    } catch (_) {
-      // NOTE(turnidge): Sometimes polymer updates give us garbage
-      // starts and limits during page updates.
-      return "OOB";
-    }
-  }
-
-  MutationObserver _observer;
-
   void _scrollToCurrentPos() {
-    var line = shadowRoot.querySelector('#line-$currentLine');
+    var line = querySelector('#${makeLineId(currentLine)}');
     if (line != null) {
       line.scrollIntoView();
     }
   }
 
-  void _onMutation(mutations, observer) {
-    _scrollToCurrentPos();
-  } 
-
-  void attached() {
-    super.attached();
-    var table = shadowRoot.querySelector('.sourceTable');
-    if (table != null) {
-      _observer = new MutationObserver(_onMutation);
-      _observer.observe(table, childList:true);
-    }
-  }
-
   void detached() {
-    if (_observer != null) {
-      _observer.disconnect();
-      _observer = null;
+    if (scriptChangeSubscription != null) {
+      // Don't leak. If only Dart and Javascript exposed weak references...
+      scriptChangeSubscription.cancel();
+      scriptChangeSubscription = null;
     }
     super.detached();
   }
 
   void currentPosChanged(oldValue) {
-    _updateLines();
+    update();
     _scrollToCurrentPos();
   }
 
   void startPosChanged(oldValue) {
-    _updateLines();
+    update();
   }
 
   void endPosChanged(oldValue) {
-    _updateLines();
+    update();
   }
 
   void scriptChanged(oldValue) {
-    _updateLines();
+    update();
   }
 
-  var _updateFuture;
+  // Styles.
+  Element a(String text) => new AnchorElement()..text = text;
+  Element span(String text) => new SpanElement()..text = text;
+  Element monospace(Element element) {
+    element.style.fontFamily = "consolas, courier, monospace";
+    return element;
+  }
+  Element row(Element element) {
+    element.style.display = "table-row";
+    return element;
+  }
+  Element cell(Element element) {
+    element.style.display = "table-cell";
+    element.style.verticalAlign = "top";
+    return element;
+  }
+  Element hitsUnknown(Element element) {
+    element.style.backgroundColor = "";
+    element.title = "";
+    return element;
+  }
+  Element hitsNotExecuted(Element element) {
+    element.style.backgroundColor = "#e66";
+    element.title = "Line did not execute";
+    return element;
+  }
+  Element hitsExecuted(Element element) {
+    element.style.backgroundColor = "#6d6";
+    element.title = "Line did execute";
+    return element;
+  }
 
-  void _updateLines() {
-    linesReady = false;
-    if (_updateFuture != null) {
-      // Already scheduled.
-      return;
-    }
-    if (script == null) {
-      // Wait for script to be assigned.
-      return;
-    }
+  void update() {
+    if (script == null) return;

[Cutch, 2015/02/27 14:44:33]

curlies- if ( ... ) { return; }

should you ensure the script children are cleared?

[rmacnak, 2015/02/27 20:55:34]

Done.
 
I don't follow. The whole subtree is swapped at the end.

     if (!script.loaded) {
-      _updateFuture = script.load().then((_) {
-        if (script.loaded) {
-          _updateFuture = null;
-          _updateLines();
-        }
-      });
-      return;
+      return script.load().then((_) => update());
+    }
+
+    if (scriptChangeSubscription == null) {
+      scriptChangeSubscription = script.changes.listen((_) => update());
     }
+
+    computeAnnotations();
+
+    var table = linesTable();
+    children.clear();
+    children.add(table);
+  }
+
+  void computeAnnotations() {
     startLine = (startPos != null
                  ? script.tokenToLine(startPos)
                  : 1);
@@ -126,33 +149,100 @@ class ScriptInsetElement extends ObservatoryElement {
                ? script.tokenToLine(endPos)
                : script.lines.length);
 
-    lines.clear();
-    int blankLineCount = 0;
-    for (int i = (startLine - 1); i <= (endLine - 1); i++) {
-      if (script.lines[i].isBlank) {
-        // Try to introduce elipses if there are 4 or more contiguous blank lines.
-        blankLineCount++;
-      } else {
-        if (blankLineCount > 0) {
-          int firstBlank = i - blankLineCount;
-          int lastBlank = i - 1;
-          if (blankLineCount < 4) {
-            // Too few blank lines for an elipsis.
-            for (int j = firstBlank; j  <= lastBlank; j++) {
-              lines.add(script.lines[j]);
-            }
-          } else {
-            // Add an elipsis for the skipped region.
-            lines.add(script.lines[firstBlank]);
-            lines.add(null);
-            lines.add(script.lines[lastBlank]);
-          }
-          blankLineCount = 0;
-        }
-        lines.add(script.lines[i]);
+    annotations.clear();
+    if (currentLine != null) {
+      var a = new Annotation();
+      a.line = currentLine;
+      a.columnStart = currentCol;
+      a.columnStop = currentCol + 1;
+      a.title = "Current invocation";
+      annotations.add(a);
+    }
+
+    // TODO(rmacnak): Call site data.
+  }
+
+  Element linesTable() {
+    var table = new DivElement();
+    table.style.fontFamily = "monospace";

[Cutch, 2015/02/27 14:44:33]

use css classes defined in html instead of setting style properties from code.

[rmacnak, 2015/02/27 20:55:34]

Done.

+    table.style.fontWeight = "400";
+    table.style.display = "table";
+    table.style.backgroundColor = "#f5f5f5";
+    table.style.border = "1px solid #ccc";
+    table.style.padding = "10px";
+    table.style.overflowY = "auto";
+    table.style.width = "100%";
+
+    int lineNumber = 1;
+    annotationsCursor = 0;
+    for (ScriptLine line in script.lines) {
+      if (startLine <= lineNumber && lineNumber <= endLine) {
+        table.append(lineElement(line));
       }
+      lineNumber++;
     }
-    linesReady = true;
+
+    return table;
+  }
+
+  // Assumes annotations are sorted.
+  Annotation nextAnnotationOnLine(int line) {
+    if (annotationsCursor >= annotations.length) return null;
+    var annotation = annotations[annotationsCursor];
+    if (annotation.line != line) return null;
+    annotationsCursor++;
+    return annotation;
+  }
+
+  Element lineElement(ScriptLine line) {
+    return row(new DivElement())
+        ..append(cell(lineBreakpointElement(line)))
+        ..append(cell(lineNumberElement(line)))
+        ..append(cell(lineSourceElement(line)));
+  }
+
+  Element lineBreakpointElement(ScriptLine line) {
+    return new Element.tag("breakpoint-toggle")
+        ..line = line;
+  }
+
+  Element lineNumberElement(ScriptLine line) {
+    var lineNumber = line.line;
+    var node = monospace(span("$nbsp$lineNumber$nbsp"));
+    node.style.textAlign = "right";
+    node.style.color = "#a8a8a8";
+
+    if (line.hits == null) hitsUnknown(node);

[Cutch, 2015/02/27 14:44:33]

braces and new lines please

[rmacnak, 2015/02/27 20:55:34]

Done.

+    else if (line.hits == 0) hitsNotExecuted(node);
+    else hitsExecuted(node);
+
+    return node;
+  }
+
+  Element lineSourceElement(ScriptLine line) {
+    var node = new DivElement();
+    node.style.whiteSpace = "pre";
+    node.id = makeLineId(line.line);
+
+    var position = 0;
+    consumeUntil(var stop) {
+      if (stop <= position) return;  // Empty gap between annotations/boundries.
+      var chunk = line.text.substring(position, stop);
+      var chunkNode = monospace(span(chunk));
+      node.append(chunkNode);
+      position = stop;
+      return chunkNode;
+    }
+
+    // TODO(rmacnak): Tolerate overlapping annotations.
+    var annotation;
+    while ((annotation = nextAnnotationOnLine(line.line)) != null) {
+      consumeUntil(annotation.columnStart);
+      annotation.applyStyleTo(consumeUntil(annotation.columnStop));
+    }
+    consumeUntil(line.text.length);
+
+    return node;
   }
 
   ScriptInsetElement.created() : super.created();