fix and activate W291 (trailing whitespace) in linter

.vscode/settings.json

@@ -27,7 +27,7 @@
     "python.linting.enabled": true,
     // The following pycodestyle arguments are the same as the pycodestyle-minimal
     // tox environnment, see the file SAGE_ROOT/src/tox.ini
-    "python.linting.pycodestyleArgs": ["--select=E111,E306,E401,E701,E702,E703,W391,W605,E711,E712,E713,E721,E722"],
+    "python.linting.pycodestyleArgs": ["--select=E111,E306,E401,E701,E702,E703,W291,W391,W605,E711,E712,E713,E721,E722"],
     "cSpell.words": [
         "furo",
         "Conda",

src/conftest_inputtest.py

@@ -1,6 +1,6 @@
 def something():
     """ a doctest in a docstring
-    
+
     EXAMPLES::
 
         sage: something()

src/sage/combinat/diagram.py

@@ -856,7 +856,7 @@ def peelable_tableaux(self):
 
         For a fixed northwest diagram `D`, we say that a Young tableau `T` is
         `D`-peelable if:
-        
+
         1. the row indices of the cells in the first column of `D` are
            the entries in an initial segment in the first column of `T` and
         2. the tableau `Q` obtained by removing those cells from `T` and playing

src/sage/combinat/matrices/hadamard_matrix.py

@@ -453,7 +453,7 @@ def hadamard_matrix(n,existence=False, check=True):
             return True
         M = skew_hadamard_matrix(n, check=False)
     elif regular_symmetric_hadamard_matrix_with_constant_diagonal(n, 1, existence=True) is True:
-        if existence: 
+        if existence:
             return True
         M = regular_symmetric_hadamard_matrix_with_constant_diagonal(n, 1)
     else:

src/sage/geometry/hyperplane_arrangement/plot.py

@@ -103,9 +103,9 @@
     sage: a.plot(hyperplane_labels=True,label_colors=['red','green','black'])  # optional - sage.plot
     Graphics3d Object
 """
-
 from copy import copy
 from colorsys import hsv_to_rgb
+
 from sage.misc.lazy_import import lazy_import
 lazy_import("sage.plot.plot3d.parametric_plot3d", "parametric_plot3d")
 lazy_import("sage.plot.plot3d.shapes2", "text3d")
@@ -119,7 +119,7 @@
 
 def plot(hyperplane_arrangement, **kwds):
     r"""
-    Return a plot of the hyperplane arrangement.  
+    Return a plot of the hyperplane arrangement.
 
     If the arrangement is in 4 dimensions but inessential, a plot of
     the essentialization is returned.

src/sage/geometry/ribbon_graph.py

@@ -1,9 +1,9 @@
 r"""
 Ribbon Graphs
 
-This file implements objects called *ribbon graphs*. These are graphs 
-together with a cyclic ordering of the darts adjacent to each 
-vertex. This data allows us to unambiguously "thicken" the ribbon 
+This file implements objects called *ribbon graphs*. These are graphs
+together with a cyclic ordering of the darts adjacent to each
+vertex. This data allows us to unambiguously "thicken" the ribbon
 graph to an orientable surface with boundary. Also, every orientable
 surface with non-empty boundary is the thickening of a ribbon graph.
 
@@ -103,10 +103,10 @@ class RibbonGraph(SageObject, UniqueRepresentation):
 
     **Brief introduction**
 
-    Let `\Sigma` be an orientable surface with non-empty boundary and let 
-    `\Gamma` be the topological realization of a graph that is embedded in 
+    Let `\Sigma` be an orientable surface with non-empty boundary and let
+    `\Gamma` be the topological realization of a graph that is embedded in
     `\Sigma` in such a way that the graph is a strong deformation retract of
-    the surface. 
+    the surface.
 
     Let `v(\Gamma)` be the set of vertices of `\Gamma`, suppose that these
     are white vertices. Now we mark black vertices in an interior point
@@ -121,7 +121,7 @@ class RibbonGraph(SageObject, UniqueRepresentation):
     `\Gamma` and suppose that we enumerate the set `D(\Gamma)` and that it
     has `n` elements.
 
-    With the orientation of the surface and the embedding of the graph in 
+    With the orientation of the surface and the embedding of the graph in
     the surface we can produce two permutations:
 
     - A permutation that we denote by `\sigma`. This permutation is a
@@ -139,13 +139,13 @@ class RibbonGraph(SageObject, UniqueRepresentation):
 
     .. RUBRIC:: Abstract definition
 
-    Consider a graph `\Gamma` (not a priori embedded in any surface). 
-    Now we can again consider one vertex in the interior of each edge 
+    Consider a graph `\Gamma` (not a priori embedded in any surface).
+    Now we can again consider one vertex in the interior of each edge
     splitting each edge in two darts. We label the darts with numbers.
 
-    We say that a ribbon structure on `\Gamma` is a set of two 
+    We say that a ribbon structure on `\Gamma` is a set of two
     permutations `(\sigma, \rho)`. Where `\sigma` is formed by as many
-    disjoint cycles as vertices had `\Gamma`. And each cycle is a 
+    disjoint cycles as vertices had `\Gamma`. And each cycle is a
     cyclic ordering of the darts adjacent to a vertex. The permutation
     `\rho` just tell us which two darts belong to the same edge.
 
@@ -210,7 +210,7 @@ class RibbonGraph(SageObject, UniqueRepresentation):
         sage: R2.sigma()
         (1,3,5,8)(2,4,6)
 
-    This example is constructed by taking the bipartite graph of 
+    This example is constructed by taking the bipartite graph of
     type `(3,3)`::
 
         sage: s3 = PermutationGroupElement('(1,2,3)(4,5,6)(7,8,9)(10,11,12)(13,14,15)(16,17,18)')
@@ -384,7 +384,7 @@ def number_boundaries(self):
             sage: R1.number_boundaries()
             1
 
-        This example is constructed by taking the bipartite graph of 
+        This example is constructed by taking the bipartite graph of
         type `(3,3)`::
 
             sage: s2 = PermutationGroupElement('(1,2,3)(4,5,6)(7,8,9)(10,11,12)(13,14,15)(16,17,18)')
@@ -409,7 +409,7 @@ def contract_edge(self, k):
 
         INPUT:
 
-        - ``k`` -- non-negative integer; the position in `\rho` of the 
+        - ``k`` -- non-negative integer; the position in `\rho` of the
           transposition that is going to be contracted
 
         OUTPUT:
@@ -441,7 +441,7 @@ def contract_edge(self, k):
             ValueError: the edge is a loop and cannot be contracted
 
         In this example, we consider a graph that has one edge ``(19,20)``
-        such that one of its ends is a vertex of valency 1. This is 
+        such that one of its ends is a vertex of valency 1. This is
         the vertex ``(20)`` that is not specified when defining `\sigma`.
         We contract precisely this edge and get a ribbon graph with no
         vertices of valency 1::
@@ -514,7 +514,7 @@ def extrude_edge(self, vertex, dart1, dart2):
 
         OUTPUT:
 
-        A ribbon graph resulting from extruding a new edge that 
+        A ribbon graph resulting from extruding a new edge that
         pulls from ``vertex`` a new vertex that is, now, adjacent
         to all the darts from ``dart1``to ``dart2`` (not including
         ``dart2``) in the cyclic ordering given by the cycle corresponding
@@ -553,7 +553,7 @@ def extrude_edge(self, vertex, dart1, dart2):
             (1,2)(3,4)(5,6)(7,8)
 
         In the following example we first extrude one edge from a vertex
-        of valency 3 generating a new vertex of valency 2. Then we 
+        of valency 3 generating a new vertex of valency 2. Then we
         extrude a new edge from this vertex of valency 2::
 
             sage: s1 = PermutationGroupElement('(1,3,5)(2,4,6)')
@@ -674,7 +674,7 @@ def boundary(self):
 
         OUTPUT:
 
-        A list of lists. The number of inner lists is the number of 
+        A list of lists. The number of inner lists is the number of
         boundary components of the surface. Each list in the list
         consists of an ordered tuple of numbers, each number comes
         from the number assigned to the corresponding dart before
@@ -878,7 +878,7 @@ def make_generic(self):
 
     def homology_basis(self):
         r"""
-        Return an oriented basis of the first homology group of the 
+        Return an oriented basis of the first homology group of the
         graph.
 
         OUTPUT:
@@ -1098,8 +1098,8 @@ def make_ribbon(g, r):
 
     OUTPUT:
 
-    - a ribbon graph that has 2 vertices (two non-trivial cycles 
-      in its sigma permutation) of valency `2g + r` and it has 
+    - a ribbon graph that has 2 vertices (two non-trivial cycles
+      in its sigma permutation) of valency `2g + r` and it has
       `2g + r` edges (and hence `4g + 2r` darts)
 
     EXAMPLES::

src/sage/geometry/triangulation/point_configuration.py

@@ -1865,7 +1865,7 @@ def contained_simplex(self, large=True, initial_point=None, point_order=None):
             sage: pc.contained_simplex()
             (P(-1, -1), P(1, 1), P(0, 1))
             sage: pc.contained_simplex(point_order = [pc[1],pc[3],pc[4],pc[2],pc[0]])
-            (P(0, 1), P(1, 1), P(-1, -1)) 
+            (P(0, 1), P(1, 1), P(-1, -1))
 
         Lower-dimensional example::
 

src/sage/libs/eclib/interface.py

@@ -731,20 +731,20 @@ class mwrank_MordellWeil(SageObject):
         Reducing saturation bound from given value 20 to computed index bound 3
         Tamagawa index primes are [ 2 ]
         Checking saturation at [ 2 3 ]
-        Checking 2-saturation 
+        Checking 2-saturation
         Points were proved 2-saturated (max q used = 7)
-        Checking 3-saturation 
+        Checking 3-saturation
         Points were proved 3-saturated (max q used = 7)
         done
         P2 = [-2:3:1]     is generator number 2
         saturating up to 20...Saturation index bound (for points of good reduction)  = 4
         Reducing saturation bound from given value 20 to computed index bound 4
         Tamagawa index primes are [ 2 ]
         Checking saturation at [ 2 3 ]
-        Checking 2-saturation 
+        Checking 2-saturation
         possible kernel vector = [1,1]
         This point may be in 2E(Q): [14:-52:1]
-        ...and it is! 
+        ...and it is!
         Replacing old generator #1 with new generator [1:-1:1]
         Reducing index bound from 4 to 2
         Points have successfully been 2-saturated (max q used = 7)
@@ -756,9 +756,9 @@ class mwrank_MordellWeil(SageObject):
         Reducing saturation bound from given value 20 to computed index bound 3
         Tamagawa index primes are [ 2 ]
         Checking saturation at [ 2 3 ]
-        Checking 2-saturation 
+        Checking 2-saturation
         Points were proved 2-saturated (max q used = 11)
-        Checking 3-saturation 
+        Checking 3-saturation
         Points were proved 3-saturated (max q used = 13)
         done, index = 1.
         P4 = [-1:3:1]    = -1*P1 + -1*P2 + -1*P3 (mod torsion)
@@ -911,10 +911,10 @@ def process(self, v, saturation_bound=0):
             The resulting points may not be p-saturated for p between this and the computed index bound 93
             Tamagawa index primes are [ 2 ]
             Checking saturation at [ 2 ]
-            Checking 2-saturation 
+            Checking 2-saturation
             possible kernel vector = [1,0,0]
             This point may be in 2E(Q): [1547:-2967:343]
-            ...and it is! 
+            ...and it is!
             Replacing old generator #1 with new generator [-2:3:1]
             Reducing index bound from 93 to 46
             Points have successfully been 2-saturated (max q used = 11)
@@ -933,12 +933,12 @@ def process(self, v, saturation_bound=0):
             The resulting points may not be p-saturated for p between this and the computed index bound 46
             Tamagawa index primes are [ 2 ]
             Checking saturation at [ 2 3 ]
-            Checking 2-saturation 
+            Checking 2-saturation
             Points were proved 2-saturated (max q used = 11)
-            Checking 3-saturation 
+            Checking 3-saturation
             possible kernel vector = [0,1,0]
             This point may be in 3E(Q): [2707496766203306:864581029138191:2969715140223272]
-            ...and it is! 
+            ...and it is!
             Replacing old generator #2 with new generator [-14:25:8]
             Reducing index bound from 46 to 15
             Points have successfully been 3-saturated (max q used = 13)
@@ -957,14 +957,14 @@ def process(self, v, saturation_bound=0):
             The resulting points may not be p-saturated for p between this and the computed index bound 15
             Tamagawa index primes are [ 2 ]
             Checking saturation at [ 2 3 5 ]
-            Checking 2-saturation 
+            Checking 2-saturation
             Points were proved 2-saturated (max q used = 11)
-            Checking 3-saturation 
+            Checking 3-saturation
             Points were proved 3-saturated (max q used = 13)
-            Checking 5-saturation 
+            Checking 5-saturation
             possible kernel vector = [0,0,1]
             This point may be in 5E(Q): [-13422227300:-49322830557:12167000000]
-            ...and it is! 
+            ...and it is!
             Replacing old generator #3 with new generator [1:-1:1]
             Reducing index bound from 15 to 3
             Points have successfully been 5-saturated (max q used = 71)
@@ -981,9 +981,9 @@ def process(self, v, saturation_bound=0):
             saturating basis...Saturation index bound (for points of good reduction)  = 3
             Tamagawa index primes are [ 2 ]
             Checking saturation at [ 2 3 ]
-            Checking 2-saturation 
+            Checking 2-saturation
             Points were proved 2-saturated (max q used = 11)
-            Checking 3-saturation 
+            Checking 3-saturation
             Points were proved 3-saturated (max q used = 13)
             done
             (True, 1, '[ ]')
@@ -1329,6 +1329,5 @@ def points(self):
             P4 = [12:35:27]      = 1*P1 + -1*P2 + -1*P3 (mod torsion)
             sage: EQ.points()
             [[1, -1, 1], [-2, 3, 1], [-14, 25, 8]]
-
         """
         return self.__mw.getbasis()

src/sage/libs/pari/tests.py

@@ -1767,7 +1767,7 @@
     sage: eta1 = e.elleta(precision=150)[0]
     sage: eta1.sage()
     3.605463601432652085915820564207726774810268996598024745444380641429820491740 # 64-bit
-    3.60546360143265208591582056420772677481026899659802474544                    # 32-bit 
+    3.60546360143265208591582056420772677481026899659802474544                    # 32-bit
     sage: from cypari2 import Pari
     sage: pari = Pari()
 

src/sage/logic/logic.py

@@ -318,7 +318,7 @@ def combine(self, statement1, statement2):
               'CPAREN',
               'CPAREN'],
              {'a': 'False', 'b': 'False'},
-             ['a', 'b', 'b']]       
+             ['a', 'b', 'b']]
         """
         toks = ['OPAREN'] + statement1[0] + ['OR'] + statement2[0] + ['CPAREN']
         variables = dict(statement1[1])

src/sage/manifolds/catalog.py

@@ -262,11 +262,12 @@ def Torus(R=2, r=1, names=None):
     M.induced_metric()
     return M
 
+
 def RealProjectiveSpace(dim=2):
     r"""
     Generate projective space of dimension ``dim`` over the reals.
 
-    This is the topological space of lines through the origin in 
+    This is the topological space of lines through the origin in
     `\RR^{d+1}`. The standard atlas consists of `d+2` charts, which sends
     the set `U_i = \{[x_1, x_2, \ldots, x_{d+1}] : x_i \neq 0 \}` to
     `k^{d}` by dividing by `x_i` and omitting the `i`th coordinate

src/sage/manifolds/differentiable/manifold.py

@@ -3957,7 +3957,7 @@ def affine_connection(self, name, latex_name=None):
                                                                AffineConnection
         return AffineConnection(self, name, latex_name)
 
-    def metric(self, name: str, signature: Optional[int] = None, 
+    def metric(self, name: str, signature: Optional[int] = None,
                latex_name: Optional[str] = None,
                dest_map: Optional[DiffMap] = None) -> PseudoRiemannianMetric:
         r"""

src/sage/manifolds/differentiable/symplectic_form.py

@@ -498,7 +498,7 @@ def poisson_bracket(
 
     def volume_form(self, contra: int = 0) -> TensorField:
         r"""
-        Liouville volume form `\frac{1}{n!}\omega^n` associated with the 
+        Liouville volume form `\frac{1}{n!}\omega^n` associated with the
         symplectic form `\omega`, where `2n` is the dimension of the manifold.
 
         INPUT:

src/sage/modular/abvar/homspace.py

@@ -350,7 +350,7 @@ def __call__(self, M, **kwds):
             elif M.domain() == self.domain() and M.codomain() == self.codomain():
                 M = M.matrix()
             else:
-                raise ValueError("cannot convert %s into %s" % (M, self)) 
+                raise ValueError("cannot convert %s into %s" % (M, self))
         elif is_Matrix(M):
             if M.base_ring() != ZZ:
                 M = M.change_ring(ZZ)

src/sage/monoids/free_monoid_element.py

@@ -149,7 +149,7 @@ def _latex_(self):
             \alpha b
             sage: latex(b*alpha)
             b \alpha
-            sage: "%s"%latex(alpha*b)                                                                                                                                                                                       
+            sage: "%s" % latex(alpha*b)
             '\\alpha b'
         """
         s = ""
@@ -159,10 +159,10 @@ def _latex_(self):
             g = x[int(v[i][0])]
             e = v[i][1]
             if e == 1:
-                s += "%s "%(g,)
+                s += "%s " % (g,)
             else:
-                s += "%s^{%s}"%(g,e)
-        s = s.rstrip(" ") # strip the trailing whitespace caused by adding a space after each element name
+                s += "%s^{%s}" % (g, e)
+        s = s.rstrip(" ")  # strip the trailing whitespace caused by adding a space after each element name
         if len(s) == 0:
             s = "1"
         return s