From 1a5bfdb2e9d8c44438d64892bea7b785c39b7f6b Mon Sep 17 00:00:00 2001
From: Lothaire Sicot <137562979+leuriato@users.noreply.github.com>
Date: Mon, 21 Apr 2025 17:53:37 +0200
Subject: [PATCH] Sketcher: Prevent bad constraint names (#20717)

* Sketcher: Prevent bad constraint names

Ensures the constraint names only contains alphanumericals and
underscores so that they can always be used in expressions.
That way, there cannot be any unicode character or quotes that
would need to be escaped.

Fixes: https://github.com/FreeCAD/FreeCAD/issues/19767

* Add helper function to check constraint names

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Co-authored-by: Lothaire Sicot <lothaire.sicot@telecom-paris.fr>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
---
 src/Mod/Sketcher/Gui/EditDatumDialog.cpp      | 32 +++++++++++++++----
 src/Mod/Sketcher/Gui/EditDatumDialog.h        |  2 ++
 .../Sketcher/Gui/TaskSketcherConstraints.cpp  |  7 ++--
 3 files changed, 33 insertions(+), 8 deletions(-)

diff --git a/src/Mod/Sketcher/Gui/EditDatumDialog.cpp b/src/Mod/Sketcher/Gui/EditDatumDialog.cpp
index 88db1b321b..8b7eca6c2b 100644
--- a/src/Mod/Sketcher/Gui/EditDatumDialog.cpp
+++ b/src/Mod/Sketcher/Gui/EditDatumDialog.cpp
@@ -50,6 +50,23 @@ using namespace SketcherGui;
 
 /* TRANSLATOR SketcherGui::EditDatumDialog */
 
+bool SketcherGui::checkConstraintName(const Sketcher::SketchObject* sketch,
+                                      std::string constraintName)
+{
+    if (constraintName != Base::Tools::getIdentifier(constraintName)) {
+        Gui::NotifyUserError(
+            sketch,
+            QT_TRANSLATE_NOOP("Notifications", "Value Error"),
+            QT_TRANSLATE_NOOP("Notifications",
+                              "Invalid constraint name (must only contain alphanumericals and "
+                              "underscores, and must not start with digit)"));
+        return false;
+    }
+
+    return true;
+}
+
+
 EditDatumDialog::EditDatumDialog(ViewProviderSketch* vp, int ConstrNbr)
     : ConstrNbr(ConstrNbr)
     , success(false)
@@ -213,15 +230,18 @@ void EditDatumDialog::accepted()
                 }
             }
 
-            QString constraintName = ui_ins_datum->name->text().trimmed();
-            if (constraintName.toStdString() != sketch->Constraints[ConstrNbr]->Name) {
-                std::string escapedstr =
-                    Base::Tools::escapedUnicodeFromUtf8(constraintName.toUtf8().constData());
-                escapedstr = Base::Tools::escapeQuotesFromString(escapedstr);
+            std::string constraintName = ui_ins_datum->name->text().trimmed().toStdString();
+            std::string currConstraintName = sketch->Constraints[ConstrNbr]->Name;
+            printf("datum");
+            if (constraintName != currConstraintName) {
+                if (!SketcherGui::checkConstraintName(sketch, constraintName)) {
+                    constraintName = currConstraintName;
+                }
+
                 Gui::cmdAppObjectArgs(sketch,
                                       "renameConstraint(%d, u'%s')",
                                       ConstrNbr,
-                                      escapedstr.c_str());
+                                      constraintName.c_str());
             }
 
             Gui::Command::commitCommand();
diff --git a/src/Mod/Sketcher/Gui/EditDatumDialog.h b/src/Mod/Sketcher/Gui/EditDatumDialog.h
index 64cb732af5..1aec82147e 100644
--- a/src/Mod/Sketcher/Gui/EditDatumDialog.h
+++ b/src/Mod/Sketcher/Gui/EditDatumDialog.h
@@ -38,6 +38,8 @@ namespace SketcherGui
 class ViewProviderSketch;
 class Ui_InsertDatum;
 
+bool checkConstraintName(const Sketcher::SketchObject* sketch, std::string constraintName);
+
 class EditDatumDialog: public QObject
 {
     Q_OBJECT
diff --git a/src/Mod/Sketcher/Gui/TaskSketcherConstraints.cpp b/src/Mod/Sketcher/Gui/TaskSketcherConstraints.cpp
index ac63cf052d..a0fc18624c 100644
--- a/src/Mod/Sketcher/Gui/TaskSketcherConstraints.cpp
+++ b/src/Mod/Sketcher/Gui/TaskSketcherConstraints.cpp
@@ -1223,13 +1223,16 @@ void TaskSketcherConstraints::onListWidgetConstraintsItemChanged(QListWidgetItem
     // b) that the text in the widget item, basename, is not ""
     // otherwise a checkbox change will trigger a rename on the first execution, bloating the
     // constraint icons with the default constraint name "constraint1, constraint2"
+    printf("task");
     if (newName != currConstraintName && !basename.empty()) {
-        std::string escapedstr = Base::Tools::escapedUnicodeFromUtf8(newName.c_str());
+        if (!SketcherGui::checkConstraintName(sketch, newName)) {
+            newName = currConstraintName;
+        }
 
         Gui::Command::openCommand(QT_TRANSLATE_NOOP("Command", "Rename sketch constraint"));
         try {
             Gui::cmdAppObjectArgs(
-                sketch, "renameConstraint(%d, u'%s')", it->ConstraintNbr, escapedstr.c_str());
+                sketch, "renameConstraint(%d, u'%s')", it->ConstraintNbr, newName.c_str());
             Gui::Command::commitCommand();
         }
         catch (const Base::Exception& e) {