--- /dev/null
+// check/paranoia_check.cpp
+
+/* This set of tests checks for some of GiNaC's oopses which showed up during
+ * development. Things were evaluated wrongly and so. It should not find such
+ * a sick behaviour again. But since we are paranoic and we want to exclude
+ * that behaviour for good... */
+
+#include "ginac.h"
+
+// The very first pair of historic problems had its roots in power.cpp and was
+// finally resolved on April 27th. (Fixing the first on April 23rd actually
+// introduced the second.)
+static unsigned paranoia_check1(void)
+{
+ unsigned result = 0;
+ symbol x("x"), y("y"), z("z");
+ ex e, f, g;
+
+ e = x * y * z;
+ f = y * z;
+ g = e / f;
+
+ // In the first one expand did not do any job at all:
+ if ( !g.expand().is_equal(x) ) {
+ clog << "e = x*y*z; f = y*z; expand(e/f) erroneously returned "
+ << g.expand() << endl;
+ ++result;
+ }
+
+ // This one somehow used to return 0:
+ e = pow(x + 1, -1);
+ if (!e.expand().is_equal(e)) {
+ clog << "expand(pow(x + 1, -1)) erroneously returned "
+ << e.expand() << endl;
+ ++result;
+ }
+
+ return result;
+}
+
+// And here the second oops which showed up until May 17th 1999. It had to do
+// with lexicographic canonicalization and thus showed up only if the variables
+// had the names as given here:
+static unsigned paranoia_check2(void)
+{
+ unsigned result = 0;
+ symbol x("x"), y("y"), z("z");
+ ex e, f, g;
+
+ e = x + z*x;
+ f = e*y;
+ g = f - e*y;
+
+ // After .expand(), g should be zero:
+ if (!g.expand().is_equal(exZERO())) {
+ clog << "e = (x + z*x); f = e*y; expand(f - e*y) erroneously returned "
+ << g.expand() << endl;
+ ++result;
+ }
+ // After .eval(), g should be zero:
+ if (!g.eval().is_equal(exZERO())) {
+ clog << "e = (x + z*x); f = e*y; eval(f - e*y) erroneously returned "
+ << g.eval() << endl;
+ ++result;
+ }
+ // This actually worked already back in April. But we are very paranoic!
+ if (!g.expand().eval().is_equal(exZERO())) {
+ clog << "e = (x + z*x); f = e*y; eval(expand(f - e*y)) erroneously returned "
+ << g.expand().eval() << endl;
+ ++result;
+ }
+
+ return result;
+}
+
+// The third bug was introduced on May 18, discovered on May 19 and fixed that
+// same day. It worked when x was substituted by 1 but not with other numbers:
+static unsigned paranoia_check3(void)
+{
+ unsigned result = 0;
+ symbol x("x"), y("y");
+ ex e, f;
+
+ e = x*y - y;
+ f = e.subs(x == 2);
+
+ if (!f.is_equal(y)) {
+ clog << "e = x*y - y; f = e.subs(x == 2) erroneously returned "
+ << f << endl;
+ ++result;
+ }
+ if (!f.eval().is_equal(y)) {
+ clog << "e = x*y - y; eval(e.subs(x == 2)) erroneously returned "
+ << f.eval() << endl;
+ ++result;
+ }
+ if (!f.expand().is_equal(y)) {
+ clog << "e = x*y - y; expand(e.subs(x == 2)) erroneously returned "
+ << f.expand() << endl;
+ ++result;
+ }
+
+ return result;
+}
+
+// The fourth bug was also discovered on May 19 and fixed immediately:
+static unsigned paranoia_check4(void)
+{
+ unsigned result = 0;
+ symbol x("x");
+ ex e, f, g;
+
+ e = pow(x, 2) + x + 1;
+ f = pow(x, 2) + x + 1;
+ g = e - f;
+
+ if (!g.is_equal(exZERO())) {
+ clog << "e = pow(x,2) + x + 1; f = pow(x,2) + x + 1; g = e-f; g erroneously returned "
+ << g << endl;
+ ++result;
+ }
+ if (!g.is_equal(exZERO())) {
+ clog << "e = pow(x,2) + x + 1; f = pow(x,2) + x + 1; g = e-f; g.eval() erroneously returned "
+ << g.eval() << endl;
+ ++result;
+ }
+
+ return result;
+}
+
+// The fifth oops was discovered on May 20 and fixed a day later:
+static unsigned paranoia_check5(void)
+{
+ unsigned result = 0;
+ symbol x("x"), y("y");
+
+ ex e, f;
+ e = pow(x*y + 1, 2);
+ f = pow(x, 2) * pow(y, 2) + 2*x*y + 1;
+
+ if (!(e-f).expand().is_equal(exZERO())) {
+ clog << "e = pow(x*y+1,2); f = pow(x,2)*pow(y,2) + 2*x*y + 1; (e-f).expand() erroneously returned "
+ << (e-f).expand() << endl;
+ ++result;
+ }
+
+ return result;
+}
+
+// This one was discovered on Jun 1 and fixed the same day:
+static unsigned paranoia_check6(void)
+{
+ unsigned result = 0;
+ symbol x("x");
+
+ ex e, f;
+ e = pow(x, -5);
+ f = e.denom();
+
+ if (!f.is_equal(pow(x, 5))) {
+ clog << "e = pow(x, -5); f = e.denom(); f was " << f << " (should be x^5)" << endl;
+ ++result;
+ }
+ return result;
+}
+
+// This one was introduced on June 1 by some aggressive manual optimization.
+// Discovered and fixed on June 2.
+static unsigned paranoia_check7(void)
+{
+ unsigned result = 0;
+ symbol x("x"), y("y");
+
+ ex e = y + y*x + 2;
+ ex f = expand(pow(e, 2) - (e*y*(x + 1)));
+
+ if (f.nops() > 3) {
+ clog << "e=y+y*x+2; f=expand(pow(e,2)-(e*y*(x+1))) has "
+ << f.nops() << " arguments instead of 3 ( f=="
+ << f << " )" << endl;
+ ++result;
+ }
+ return result;
+}
+
+// This one was a result of the rewrite of mul::max_coefficient when we
+// introduced the overall_coefficient field in expairseq objects on Oct 1.
+// Fixed on Oct 4.
+static unsigned paranoia_check8(void)
+{
+ unsigned result = 0;
+ symbol x("x");
+
+ ex e = -x / (x+1);
+ ex f = e.normal();
+
+ // The bug caused a division by zero in normal(), so the following
+ // check is actually bogus...
+ if (!f.is_equal(e)) {
+ clog << "normal(-x/(x+1)) returns " << f << " instead of -x/(x+1)\n";
+ ++result;
+ }
+ return result;
+}
+
+unsigned paranoia_check(void)
+{
+ unsigned result = 0;
+
+ cout << "checking several ex-bugs just out of pure paranoia..." << flush;
+ clog << "---------several ex-bugs just out of pure paranoia:" << endl;
+
+ result += paranoia_check1();
+ result += paranoia_check2();
+ result += paranoia_check3();
+ result += paranoia_check4();
+ result += paranoia_check5();
+ result += paranoia_check6();
+ result += paranoia_check7();
+ result += paranoia_check8();
+
+ if (! result) {
+ cout << " passed ";
+ clog << "(no output)" << endl;
+ } else {
+ cout << " failed ";
+ }
+
+ return result;
+}
git://www.ginac.de / ginac.git / blobdiff