gui: add the TCL stacktrace to the output on error

An anonymous contributor provided this code.

Signed-off-by: Matt Liberty <[email protected]>

Author: maliberty

src/gui/src/cmdInputWidget.h

@@ -34,6 +34,7 @@ class CmdInputWidget : public QPlainTextEdit
   void commandFinishedExecuting(bool is_ok);
 
   void addResultToOutput(const QString& result, bool is_ok);
+  void addTextToOutput(const QString& text, const QColor& color);
   void addCommandToOutput(const QString& cmd);
 
  public slots:

src/gui/src/scriptWidget.cpp

@@ -75,6 +75,11 @@ ScriptWidget::ScriptWidget(QWidget* parent)
           &TclCmdInputWidget::addResultToOutput,
           this,
           &ScriptWidget::addResultToOutput);
+  connect(input_,
+          &TclCmdInputWidget::addTextToOutput,
+          this,
+          &ScriptWidget::addTextToOutput,
+          Qt::QueuedConnection);
   connect(input_,
           &TclCmdInputWidget::commandFinishedExecuting,
           this,

src/gui/src/tclCmdInputWidget.cpp

@@ -80,10 +80,10 @@ void TclCmdInputWidget::setTclInterp(Tcl_Interp* interp,
     // OpenRoad is not initialized
     emit commandAboutToExecute();
     QCoreApplication::processEvents(QEventLoop::ExcludeUserInputEvents);
-    const bool setup_tcl_result = ord::tclInit(interp_) == TCL_OK;
+    const int setup_tcl_result = ord::tclInit(interp_);
     post_or_init();
     processTclResult(setup_tcl_result);
-    emit commandFinishedExecuting(setup_tcl_result);
+    emit commandFinishedExecuting(setup_tcl_result == TCL_OK);
   } else {
     post_or_init();
   }
@@ -675,7 +675,7 @@ void TclCmdInputWidget::executeCommand(const QString& cmd,
 
   if (!silent) {
     // Show its output
-    processTclResult(is_ok);
+    processTclResult(return_code);
 
     if (is_ok) {
       // record the successful command to tcl history command
@@ -685,16 +685,36 @@ void TclCmdInputWidget::executeCommand(const QString& cmd,
   } else {
     if (!is_ok) {
       // Show output on error despite silent
-      processTclResult(is_ok);
+      processTclResult(return_code);
     }
   }
 
   emit commandFinishedExecuting(is_ok);
 }
 
-void TclCmdInputWidget::processTclResult(bool is_ok)
+void TclCmdInputWidget::processTclResult(const int tcl_result)
 {
+  const bool is_ok = (tcl_result == TCL_OK);
   emit addResultToOutput(Tcl_GetString(Tcl_GetObjResult(interp_)), is_ok);
+
+  if (!is_ok) {
+    // Tcl_GetReturnOptions returns an object with a ref count of 0.
+    // We DO NOT own it and MUST NOT decrement its ref count.
+    Tcl_Obj* options = Tcl_GetReturnOptions(interp_, tcl_result);
+
+    // Create a key to look up the stack trace in the options dictionary.
+    Tcl_Obj* key = Tcl_NewStringObj("-errorinfo", -1);  // refCount is now 1
+
+    // Look up the stack trace.
+    Tcl_Obj* stackTrace = nullptr;
+    if (Tcl_DictObjGet(nullptr, options, key, &stackTrace) == TCL_OK
+        && stackTrace) {
+      const char* result_msg = Tcl_GetString(stackTrace);
+      emit addTextToOutput(QString::fromStdString(result_msg), Qt::red);
+    }
+
+    Tcl_DecrRefCount(key);
+  }
 }
 
 }  // namespace gui

src/gui/src/tclCmdInputWidget.h

@@ -67,7 +67,7 @@ class TclCmdInputWidget : public CmdInputWidget
 
  private:
   void init();
-  void processTclResult(bool is_ok);
+  void processTclResult(int tcl_result);
 
   static int tclExitHandler(ClientData instance_data,
                             Tcl_Interp* interp,