sagemathgh-39347: activate check for ruff PLW0127

    
activate one more check in the `ruff-minimal` linter:

PLW0127 Self-assignment of variable

### 📝 Checklist

- [x] The title is concise and informative.
- [x] The description explains in detail what this PR is about.
    
URL: sagemath#39347
Reported by: Frédéric Chapoton
Reviewer(s): Kwankyu Lee

src/sage/combinat/designs/orthogonal_arrays_build_recursive.py

@@ -837,14 +837,14 @@ def thwart_lemma_4_1(k, n, m, explain_construction=False):
     # - (1+t,t,1+t), (1,1,1), (1+t,t,t), (1,1,2), (0,0,1), (1,0,1), (0,1,1+t),
     #   (0,1,1), (1,0,-t)
     points = [(1+t,t,1+t), (1,1,1), (1+t,t,t), (1,1,2), (0,0,1), (1,0,1), (0,1,1+t), (0,1,1), (1,0,-t)]
-    points = [[K(_) for _ in t] for t in points] # triples of K^3
+    points = [[K(c) for c in t] for t in points] # triples of K^3
     AG_2_3 = []
     for x,y,z in points:
         if z != 0:
-            x,y,z = x/z,y/z,z/z
+            x, y, z = x / z, y / z, K.one()
             AG_2_3.append(relabel[x]+n*relabel[y])
         elif y != 0:
-            x,y,z = x/y,y/y,z
+            x, y = x / y, K.one()
             AG_2_3.append(q**2+relabel[x])
         else:
             AG_2_3.append(q**2+q)

src/sage/combinat/skew_tableau.py

@@ -1042,10 +1042,10 @@ def backward_slide(self, corner=None):
             # -1, which doesn't trigger the conditional
             if P_left > P_up:
                 new_st[i][j] = P_left
-                i, j = (i, j - 1)
+                j = j - 1
             else:  # if they are equal, we slide up
                 new_st[i][j] = P_up
-                i, j = (i - 1, j)
+                i = i - 1
         # We don't need to reset the intermediate cells inside the loop
         # because the conditional above will continue to overwrite it until
         # the while loop terminates. We do need to reset it at the end.

src/sage/interacts/library.py

@@ -925,7 +925,7 @@ def bisection_method(title, f, interval, d, maxn):
           maxn: IntSlider(value=10, description='max iterations', max=15)
     """
     def _bisection_method(f, a, b, maxn, eps):
-        intervals = [(a,b)]
+        intervals = [(a, b)]
         round = 1
         two = float(2)
         while True:
@@ -938,12 +938,12 @@ def _bisection_method(f, a, b, maxn, eps):
             if abs(fc) < eps:
                 return c, intervals
             if fa*fc < 0:
-                a, b = a, c
+                b = c
             elif fc*fb < 0:
-                a, b = c, b
+                a = c
             else:
                 raise ValueError("f must have a sign change in the interval (%s,%s)" % (a,b))
-            intervals.append((a,b))
+            intervals.append((a, b))
             round += 1
         return c, intervals
 

src/tox.ini

@@ -311,7 +311,7 @@ passenv = RUFF_OUTPUT_FORMAT
 #      1        F402    [ ] Import `factor` from line 259 shadowed by loop variable
 #      1        PLC0208 [*] Use a sequence type instead of a `set` when iterating over values
 #
-commands = ruff check --ignore E402,E721,E731,E741,E742,E743,F401,F402,F403,F405,F821,F841,I001,PLC0206,PLC0208,PLC2401,PLC3002,PLE0302,PLR0124,PLR0402,PLR0911,PLR0912,PLR0913,PLR0915,PLR1704,PLR1711,PLR1714,PLR1716,PLR1736,PLR2004,PLR5501,PLW0120,PLW0127,PLW0211,PLW0602,PLW0603,PLW0642,PLW1508,PLW1510,PLW2901,PLW3301 {posargs:{toxinidir}/sage/}
+commands = ruff check --ignore E402,E721,E731,E741,E742,E743,F401,F402,F403,F405,F821,F841,I001,PLC0206,PLC0208,PLC2401,PLC3002,PLE0302,PLR0124,PLR0402,PLR0911,PLR0912,PLR0913,PLR0915,PLR1704,PLR1711,PLR1714,PLR1716,PLR1736,PLR2004,PLR5501,PLW0120,PLW0211,PLW0602,PLW0603,PLW0642,PLW1508,PLW1510,PLW2901,PLW3301 {posargs:{toxinidir}/sage/}
 
 [flake8]
 rst-roles =