sagemathgh-36789: Make "large multiplication" larger in coerce_action…

…s.pyx

    
A doctest in coerce_actions.pyx tests whether "large multiplications can
be interrupted". Depending on the random input and on the speed of the
machine, that multiplication can happen too fast, and then the interrupt
doesn't happen in time. So let's make the multiplication take longer.

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This should fix sagemath#35973.

In some testing: this multiplication uses `P = E.random_element()` where
`E` is some elliptic curve. If this happens to be `(0:1:0)`, then on at
least one machine, the multiplication is completed too quickly. We could
reject that particular point, or we can increase the multiplication by a
factor of 10. This PR uses the second approach.

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URL: sagemath#36789
Reported by: John H. Palmieri
Reviewer(s):

src/sage/structure/coerce_actions.pyx

@@ -781,7 +781,8 @@ cdef class IntegerMulAction(IntegerAction):
         Check that large multiplications can be interrupted::
 
             sage: # needs sage.schemes
-            sage: alarm(0.001); 2^(10^7) * P
+            sage: P = E([2,1,1])
+            sage: alarm(0.001); 2^(10^8) * P
             Traceback (most recent call last):
             ...
             AlarmInterrupt