get rid of comparison using _cmp_

[fchapoton]

and use _richcmp_ instead

So far, this remains used only in complex MPC and Integer classes.

CC: @tscrim

Component: refactoring

Author: Frédéric Chapoton

Branch/Commit: e6963fb

Reviewer: Travis Scrimshaw

Issue created by migration from https://trac.sagemath.org/ticket/30130

[fchapoton]

Branch: u/chapoton/30130

[fchapoton]

Commit: 066b9d9

[fchapoton]

comment:1

This seems to reveal a bug in the pickling of complex numbers. Namely

sage: C = MPComplexField(prec=200, rnd='RNDUU')
sage: b = C(393.39203845902384098234098230948209384028340)
sage: loads(dumps(b))
393.39203845902384098234098230948209384028340000000000000000 + NaN*I

---

New commits:

066b9d9

get rid of `_cmp_` comparison

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

44e7434

fix the bug in complex_mpc (for string entry without imaginary part)

[sagetrac-git]

Changed commit from 066b9d9 to 44e7434

[fchapoton]

comment:3

Should be good to go now. Let us wait for the patchbot report.

[tscrim]

Reviewer: Travis Scrimshaw

[tscrim]

comment:4

What a glorious day. Green bot => positive review.

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

e6963fb

fix doc and doctests about _cmp_

[sagetrac-git]

Changed commit from 44e7434 to e6963fb

[fchapoton]

comment:6

some trivial doctest failures. Patchbot re-launched

[fchapoton]

comment:7

One fast patchbot is morally green. Travis, do you agree with my last commit ?

[tscrim]

comment:8

Yep. LGTM. Thanks.

[vbraun]

Changed branch from u/chapoton/30130 to e6963fb