[bugfix] Make sure add::eval() collects all numeric terms *correctly*.

[ginac.git] / check / exam_paranoia.cpp

diff --git a/check/exam_paranoia.cpp b/check/exam_paranoia.cpp
index bb68d33ec22d8307fe517bd8743dc1ab0b04b141..81dda8537772c5480d67862bd309e6794adde4a2 100644 (file)
--- a/check/exam_paranoia.cpp
+++ b/check/exam_paranoia.cpp
@@ -6,7 +6,7 @@
  *  these oopses for good, so we run those stupid tests... */
 
 /*
- *  GiNaC Copyright (C) 1999-2009 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2015 Johannes Gutenberg University Mainz, Germany
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -467,6 +467,116 @@ static unsigned exam_paranoia17()
        return test_cycl.get_free_indices().size();
 }
 
+// Bug in add::eval() could result in numeric terms not being collected into
+// the overall coefficient. Fixed first on Sep 22, 2010 and again on Dec 17 2015
+static unsigned exam_paranoia18()
+{
+       unsigned result = 0;
+
+       ex sqrt2 = sqrt(ex(2));
+       ex e = 1 + 2*(sqrt2+1)*(sqrt2-1);
+       if (e.real_part() != 3) {
+               clog << "real_part(1+2*(sqrt(2)+1)*(sqrt(2)-1)) failed to evaluate to 3\n";
+               ++result;
+       }
+
+       ex sqrt3 = sqrt(ex(3));
+       ex f = 2 + 2*(sqrt2+1)*(sqrt2-1) - 2*(sqrt3+1)*(sqrt3-1);
+       if (f.real_part() != 0) {
+               clog << "real_part(2+2*(sqrt(2)+1)*(sqrt(2)-1)-3*(sqrt(3)+1)*(sqrt(3)-1)) failed to evaluate to 0\n";
+               ++result;
+       }
+
+       return result;
+}
+
+// Bug in mul::conjugate when factors are evaluated at branch cuts, reported as
+// Sage bug #10964.
+static unsigned exam_paranoia19()
+{
+       symbol a("a");
+       ex e = conjugate(a*sqrt(ex(-2))*sqrt(ex(-3)));
+       ex c = a*conjugate(sqrt(ex(-2)))*conjugate(sqrt(ex(-3)));
+       if (!subs(e-c, a==42).is_zero()) {
+               clog << "subs(a*conjugate(sqrt(-2))*conjugate(sqrt(-3))-conjugate(a*sqrt(-2)*sqrt(-3)),a==42) failed to evaluate to 0\n";
+               return 1;
+       }
+       return 0;
+}
+
+// Bugs in is_polynomial (fixed 2011-05-20 and 2014-07-26).
+static unsigned exam_paranoia20()
+{
+       unsigned result = 0;
+       symbol x("x"), y("y");
+       ex e1 = sqrt(x*x+1)*sqrt(x+1);
+       if (e1.is_polynomial(x)) {
+               clog << "sqrt(x*x+1)*sqrt(x+1) is wrongly reported to be a polynomial in x\n";
+               ++result;
+       }
+       ex e2 = sqrt(Pi)*x;
+       if (!e2.is_polynomial(x)) {
+               clog << "sqrt(Pi)*x is wrongly reported to be no polynomial in x\n";
+               ++result;
+       }
+       ex e3 = sqrt(x);
+       if (!e3.is_polynomial(y)) {
+               clog << "sqrt(x) is wrongly reported to be no polynomial in y\n";
+               ++result;
+       }
+       ex e4 = (1+y)/(2+x);
+       if (e4.is_polynomial(x)) {
+               clog << "(1+y)/(2+x) is wrongly reported to be a polynomial in x\n";
+               ++result;
+       }
+       return result;
+}
+
+static unsigned is_polynomial_false_positive()
+{
+       unsigned result = 0;
+       symbol x("x"), n("n");
+       exvector nonpoly_exprs;
+       nonpoly_exprs.push_back(1/(1-x));
+       nonpoly_exprs.push_back(1/(x+1));
+       nonpoly_exprs.push_back(-1/(x-1));
+       nonpoly_exprs.push_back(1/(1-x*x));
+       nonpoly_exprs.push_back(1/(1-pow(x,n)));
+       nonpoly_exprs.push_back(x-1/(x-1));
+       for (exvector::const_iterator ep = nonpoly_exprs.begin();
+            ep != nonpoly_exprs.end(); ++ep) {
+               if (ep->is_polynomial(x)) {
+                       clog << "(" << *ep << ").is_polynomial(" << x << ") "
+                               "erroneously returned true" << endl;
+                       ++result;
+               }
+       }
+       return result;
+}
+
+// Bug in power::expand reported by Isuru Fernando (fixed 2015-05-07).
+static unsigned exam_paranoia21()
+{
+       symbol x("x");
+       ex e = pow(x + sqrt(ex(2))*x, 2).expand();
+       if (e.nops() != 2) {
+               clog << "(x+sqrt(2)*x)^2 was wrongly expanded to " << e << "\n";
+               return 1;
+       }
+       return 0;
+}
+
+// Bug in power::expand (fixed 2015-07-18).
+static unsigned exam_paranoia22()
+{
+       symbol x("x"), y("y");
+       ex e = pow(sqrt(1+x)+y*sqrt(1+x), 2).expand();
+       if (e.nops() != 6) {
+               clog << "(sqrt(1+x)+y*sqrt(1+x))^2 was wrongly expanded to " << e << "\n";
+               return 1;
+       }
+       return 0;
+}
 
 unsigned exam_paranoia()
 {
@@ -491,6 +601,12 @@ unsigned exam_paranoia()
        result += exam_paranoia15();  cout << '.' << flush;
        result += exam_paranoia16();  cout << '.' << flush;
        result += exam_paranoia17();  cout << '.' << flush;
+       result += exam_paranoia18();  cout << '.' << flush;
+       result += exam_paranoia19();  cout << '.' << flush;
+       result += exam_paranoia20();  cout << '.' << flush;
+       result += is_polynomial_false_positive(); cout << '.' << flush;
+       result += exam_paranoia21();  cout << '.' << flush;
+       result += exam_paranoia22();  cout << '.' << flush;
        
        return result;
 }