[kgraphviewer-devel] Syntax error in .dot file (plus big thankyou)

[Ivan Brezina]

Hi all,
first of all I would like to thank you for all the work you made on 
kgraphviewer.
I'm about to use a part of it in another GNU project - Tora 
(http://torasql.com/).
I spent a lot of time looking for some example of integrating graphwiz 
with QT,
and your project is the best one can find on the Internet.

Would you mind if I used part of kgraphviewer as generic planar graph 
visualization widget?

Would you accept patches that remove dependency on legacy QT3?

BTW: I've found that in some cases kgraphviewer produces .dot files 
whose are not
syntactically correct. Command dot complains about syntax error but 
processes them anyway.

For example this file has syntax error in it:
digraph "unnamed" {
graph [fontsize="11",id="unnamed"]
subgraph cluster_X1  {id="cluster_X1",label="X1",cluster_X1_T1_1  
[comment="T1",fontsize="10",id="cluster_X1_T1_1",label="T1",name="T1"];
}
}

While this one is correct:
digraph "unnamed" {
graph [fontsize="11",id="unnamed"]
subgraph cluster_X1  {
graph[id="cluster_X1",label="X1"]
cluster_X1_T1_1  
[comment="T1",fontsize="10",id="cluster_X1_T1_1",label="T1",name="T1"];
}
}

This patch adds graph declaration onto subgraph:
--- /home/ivan/devel/fragments/kgraphviewer/src/part/graphsubgraph.cpp  
2011-10-11 21:38:03.942174147 +0200
+++ ../../src/ermodel/graphsubgraph.cpp 2011-10-11 21:23:14.554748779 +0200
@@ -283,8 +279,11 @@

  QTextStream& operator<<(QTextStream& s, const GraphSubgraph& sg)
  {
-  s << "subgraph " << sg.id() << "  {"
- << dynamic_cast<const GraphElement&>(sg);
+  s << "subgraph " << sg.id() << "  {" << endl
+ << "graph [ "
+ << dynamic_cast<const GraphElement&>(sg)
+ << " ]" << endl;
+
    foreach (const GraphElement* el, sg.content())
    {
      s << *(dynamic_cast<const GraphNode*>(el));
-- end --

This patch removes trailing comma in attributes list:
--- graphelement.cpp.orig    2011-10-11 22:42:17.712174781 +0200
+++ graphelement.cpp    2011-10-11 22:48:21.732174841 +0200
@@ -177,10 +177,12 @@
  {
    QMap<QString,QString>::const_iterator it, it_end;
    it = n.attributes().begin(); it_end = n.attributes().end();
+  bool firstAttr = true;
    for (;it != it_end; it++)
    {
-    if (!it.value().isEmpty())
-    {
+    if (it.value().isEmpty())
+      continue;
+
        if (it.key() == "label")
        {
          QString label = it.value();
@@ -188,7 +190,11 @@
          {
            label.replace(QRegExp("\n"),"\\n");
  //           kDebug() << it.key() << "=\"" << label << "\",";
-          s << it.key() << "=\"" << label << "\",";
+        if (firstAttr)
+          firstAttr = false;
+        else
+      s << ',';
+        s << it.key() << "=\"" << label << '"';
          }
        }
        else if (it.key() == "_draw_" || it.key() == "_ldraw_")
@@ -198,8 +204,11 @@
        {
  //         kDebug() << it.key() << it.value();

-          s << it.key() << "=\"" << it.value() << "\",";
-      }
+        if (firstAttr)
+          firstAttr = false;
+        else
+      s << ',';
+        s << it.key() << "=\"" << it.value() << '"';
      }
    }
    return s;
-- end --

Ivan