Add tests and documentation

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 27 insertions, 1 deletions

diff --git a/sorting.c b/sorting.c
index e4bfdaf..2738081 100644
--- a/sorting.c
+++ b/sorting.c
@@ -18,7 +18,33 @@ doublepcmp(const void *avp, const void *bvp)
 int
 main(void)
 {
-	return 0; /* TODO add test */
+	double a, b;
+
+	a = 1.0, b = 1.0;
+	ASSERT(doublepcmp(&a, &b) == 0);
+	ASSERT(doublepcmp(&b, &a) == -doublepcmp(&a, &b));
+
+	a = -1.0, b = 1.0;
+	ASSERT(doublepcmp(&a, &b) == -1);
+	ASSERT(doublepcmp(&b, &a) == -doublepcmp(&a, &b));
+
+	a = 1.0, b = -1.0;
+	ASSERT(doublepcmp(&a, &b) == +1);
+	ASSERT(doublepcmp(&b, &a) == -doublepcmp(&a, &b));
+
+	a = 0.0, b = 0.0;
+	ASSERT(doublepcmp(&a, &b) == 0);
+	ASSERT(doublepcmp(&b, &a) == -doublepcmp(&a, &b));
+
+	a = -1.0, b = 2.5;
+	ASSERT(doublepcmp(&a, &b) == -1);
+	ASSERT(doublepcmp(&b, &a) == -doublepcmp(&a, &b));
+
+	a = 1.0, b = -2.5;
+	ASSERT(doublepcmp(&a, &b) == +1);
+	ASSERT(doublepcmp(&b, &a) == -doublepcmp(&a, &b));
+
+	return 0;
 }