GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it
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##
#W testrws.g automgrp package Dmytro Savchuk
#W Yevgen Muntyan
## automgrp v 1.3
##
#Y Copyright (C) 2003 - 2016 Dmytro Savchuk, Yevgen Muntyan
##
UnitTest("RWS 1", function()
local g;
g := SelfSimilarGroup("a=(1,a^-1)(1,2), b = (1, a^-1*b^2*a)");
AssertTrue(g = AG_ReducedForm(g));
AssertTrue(g.1 = AG_ReducedForm(g.1));
AssertTrue(g.2 = AG_ReducedForm(g.2));
AG_AddRelators(g, [g.2]);
AssertTrue(g = AG_ReducedForm(g));
AssertTrue(g.1 = AG_ReducedForm(g.1));
AssertTrue(g.2 = AG_ReducedForm(g.2));
AG_UseRewritingSystem(g);
AssertTrue(IsOne(g.2));
AssertTrue(g = AG_ReducedForm(g));
AssertTrue(g.1 = AG_ReducedForm(g.1));
AssertTrue(g.2 = AG_ReducedForm(g.2));
g := SelfSimilarGroup("a=(a^3,b^-1)(1,2), b = (b^3, a^-1)(1,2)");
AssertTrue(g = AG_ReducedForm(g));
AssertTrue(g.1 = AG_ReducedForm(g.1));
AssertTrue(g.2 = AG_ReducedForm(g.2));
AG_AddRelators(g, [g.1*g.2^-1]);
AssertTrue(g = AG_ReducedForm(g));
AssertTrue(g.1 = AG_ReducedForm(g.1));
AssertTrue(g.2 = AG_ReducedForm(g.2));
AG_UseRewritingSystem(g);
AssertTrue(IsOne(g.1*g.2^-1));
AssertTrue(g = AG_ReducedForm(g));
AssertTrue(g.1 = AG_ReducedForm(g.1));
AssertTrue(g.2 = AG_ReducedForm(g.2));
g := AutomatonGroup("a=(1,2), b=(a,c), c=(a,d), d=(1,b)");
AssertTrue(g = AG_ReducedForm(g));
AssertTrue(g.1 = AG_ReducedForm(g.1));
AssertTrue(g.2 = AG_ReducedForm(g.2));
AssertTrue(g.3 = AG_ReducedForm(g.3));
AssertTrue(g.4 = AG_ReducedForm(g.4));
AG_UseRewritingSystem(g);
AssertTrue(g = AG_ReducedForm(g));
AssertTrue(g.1 = AG_ReducedForm(g.1));
AssertTrue(g.2 = AG_ReducedForm(g.2));
AssertTrue(g.3 = AG_ReducedForm(g.3));
AssertTrue(g.4 = AG_ReducedForm(g.4));
AssertTrue(g.4 in Group(g.2, g.3));
AssertTrue(g.2 in Group(g.4, g.3));
AssertTrue(g.3 in Group(g.2, g.4));
end);