From d9520ae9989dfdccefdf3f20f45389cb4f632dc5 Mon Sep 17 00:00:00 2001
From: Matthias Koeppe <mkoeppe@math.ucdavis.edu>
Date: Sat, 3 Jul 2021 10:58:08 -0700
Subject: [PATCH] Chart: Add coord_restrictions init arg

---
 src/sage/manifolds/chart.py                | 14 +++++++++++---
 src/sage/manifolds/differentiable/chart.py |  4 ++--
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/src/sage/manifolds/chart.py b/src/sage/manifolds/chart.py
index 1994182cb71..30a9d193eba 100644
--- a/src/sage/manifolds/chart.py
+++ b/src/sage/manifolds/chart.py
@@ -261,7 +261,15 @@ class Chart(UniqueRepresentation, SageObject):
         manifolds over `\RR`.
 
     """
-    def __init__(self, domain, coordinates='', names=None, calc_method=None):
+    @staticmethod
+    def __classcall__(cls, domain, coordinates='', names=None, calc_method=None,
+                      coord_restrictions=None):
+
+        return super().__classcall__(cls, domain, coordinates, names, calc_method,
+                                     coord_restrictions)
+
+
+    def __init__(self, domain, coordinates, names, calc_method, coord_restrictions):
         r"""
         Construct a chart.
 
@@ -1576,7 +1584,7 @@ class RealChart(Chart):
     :meth:`plot`.
 
     """
-    def __init__(self, domain, coordinates='', names=None, calc_method=None):
+    def __init__(self, domain, coordinates, names, calc_method, coord_restrictions):
         r"""
         Construct a chart on a real topological manifold.
 
@@ -1595,7 +1603,7 @@ def __init__(self, domain, coordinates='', names=None, calc_method=None):
 
         """
         Chart.__init__(self, domain, coordinates=coordinates, names=names,
-                       calc_method=calc_method)
+                       calc_method=calc_method, coord_restrictions=coord_restrictions)
         self._fast_valid_coordinates = None
 
     def _init_coordinates(self, coord_list):
diff --git a/src/sage/manifolds/differentiable/chart.py b/src/sage/manifolds/differentiable/chart.py
index 0e0ec6205c8..00290d933d9 100644
--- a/src/sage/manifolds/differentiable/chart.py
+++ b/src/sage/manifolds/differentiable/chart.py
@@ -259,7 +259,7 @@ class DiffChart(Chart):
         on differentiable manifolds over `\RR`.
 
     """
-    def __init__(self, domain, coordinates='', names=None, calc_method=None):
+    def __init__(self, domain, coordinates, names, calc_method, coord_restrictions):
         r"""
         Construct a chart.
 
@@ -942,7 +942,7 @@ class RealDiffChart(DiffChart, RealChart):
     :meth:`~sage.manifolds.chart.RealChart.plot`.
 
     """
-    def __init__(self, domain, coordinates='', names=None, calc_method=None):
+    def __init__(self, domain, coordinates, names, calc_method, coord_restrictions):
         r"""
         Construct a chart on a real differentiable manifold.