assertThat(matcher.removeFrom(s)).isEqualTo("");
    assertThat(matcher.replaceFrom(s, 'z')).isEqualTo(Strings.repeat("z", s.length()));
    assertThat(matcher.replaceFrom(s, "ZZ")).isEqualTo(Strings.repeat("ZZ", s.length()));
    assertThat(matcher.trimFrom(s)).isEqualTo("");
    assertEquals(s.length(), matcher.countIn(s));
  }

   *       N::::::N:7$O:77777777                      N++++ZZZZN
   *       M::::::::::::N77777777+                   +?+++++ZZZM
   *       8::::::::::::D77777777M                    O+++++ZZ
   *        ::::::::::::M777777777N                      O+?D
   *        M:::::::::::M77777777778                     77=
   *        D=::::::::::N7777777777N                    777

   *       N::::::N:7$O:77777777                      N++++ZZZZN
   *       M::::::::::::N77777777+                   +?+++++ZZZM
   *       8::::::::::::D77777777M                    O+++++ZZ
   *        ::::::::::::M777777777N                      O+?D
   *        M:::::::::::M77777777778                     77=
   *        D=::::::::::N7777777777N                    777

Waterworth, Danijar Hafner, Darren Garvey, Denis Gorbachev, @DjangoPeng,
Egor-Krivov, Elia Palme, Eric Platon, Fabrizio Milo, Gaetan Semet, Georg
Nebehay, Gu Wang, Gustav Larsson, @haosdent, Harold Cooper, Hw-Zz, @ichuang,
Igor Babuschkin, Igor Macedo Quintanilha, Ilya Edrenkin, @ironhead, Jakub
Kolodziejczyk, Jennifer Guo, Jihun Choi, Jonas Rauber, Josh Bleecher Snyder,

NewIdentityPoint() func checkOnCurve(t *testing.T, points ...*Point) { t.Helper() for i, p := range points { var XX, YY, ZZ, ZZZZ field.Element XX.Square(&p.x) YY.Square(&p.y) ZZ.Square(&p.z) ZZZZ.Square(&ZZ) // -x² + y² = 1 + dx²y² // -(X/Z)² + (Y/Z)² = 1 + d(X/Z)²(Y/Z)² // (-X² + Y²)/Z² = 1 + (dX²Y²)/Z⁴ // (-X² + Y²)*Z² = Z⁴ + dX²Y² var lhs, rhs field.Element lhs.Subtract(&YY, &XX).Multiply(&lhs, &ZZ) rhs.Multiply(d, &XX).Multiply(&rhs, &YY).Add(&rhs, &ZZZZ) if lhs.Equal(&rhs) != 1 { t.Errorf("X, Y, and Z do...