[gcalctool/vala] Test factorize

[Robert Ancell <rancell src gnome org>]

commit d3f871dcb49e190a49a60ab1a7acea6aa225f63e
Author: Robert Ancell <robert ancell canonical com>
Date:   Sat Oct 13 10:07:00 2012 +1300

    Test factorize

 src/test-number.vala |   70 +++++++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 69 insertions(+), 1 deletions(-)
---
diff --git a/src/test-number.vala b/src/test-number.vala
index 01e4ab9..f4d1a9c 100644
--- a/src/test-number.vala
+++ b/src/test-number.vala
@@ -1016,6 +1016,74 @@ private void test_shift ()
     pass ();
 }
 
+private void test_factorize ()
+{
+    for (var a = 0; a < 100; a++)
+    {
+        var factors = (new Number.integer (a)).factorize ();
+        var expected = factorize (a);
+
+        var matches = false;
+        if (factors.length () == expected.length ())
+        {
+            matches = true;
+            for (var i = 0 ; i < factors.length (); i++)
+                if (factors.nth_data (i).to_integer () != expected.nth_data (i))
+                    matches = false;
+        }
+
+        if (!matches)
+        {
+            var factors_string = "";
+            foreach (var f in factors)
+            {
+                if (factors_string != "")
+                    factors_string += ", ";
+                factors_string += "%d".printf ((int) f.to_integer ());
+            }
+            var expected_string = "";
+            foreach (var f in expected)
+            {
+                if (expected_string != "")
+                    expected_string += ", ";
+                expected_string += "%d".printf (f);
+            }
+            fail ("(%d).factorize () -> (%s), expected (%s)".printf (a, factors_string, expected_string));
+            return;
+        }
+    }
+
+    pass ();
+}
+
+private List<int> factorize (int number)
+{
+    var factors = new List<int> ();
+    if (number < 2)
+    {
+        factors.append (number);
+        return factors;
+    }
+
+    var n = number;
+    while (true)
+    {
+        for (var factor = 2; factor <= n; factor++)
+        {
+            if (n % factor == 0)
+            {
+                factors.append (factor);
+                n /= factor;
+                if (n == 1)
+                    return factors;
+                break;
+            }
+        }
+    }
+
+    return factors;
+}
+
 static int main (string[] args)
 {
     Intl.setlocale (LocaleCategory.ALL, "C");
@@ -1088,7 +1156,7 @@ static int main (string[] args)
     test_shift ();
     //test_ones_complement ();
     //test_twos_complement ();
-    //test_factorize ();
+    test_factorize ();
 
     if (fail_count == 0)
         stdout.printf ("Passed all %i tests\n", pass_count);