Added test for 'sqrt' function

tests/test_sqrt

@@ -0,0 +1,24 @@
+#!/bin/sh
+
+utest() {
+    PROGRAM="$PWD/build/dc"
+    EXPECTED="5"
+    ACTUAL=$("$PROGRAM" -e '25 v p')
+    assert_eq "$EXPECTED" "$ACTUAL"
+
+    # Test empty stack
+    EXPECTED="'v' requires one operand"
+    ACTUAL=$("$PROGRAM" -e 'v' 2>&1) || true
+    assert_eq "$EXPECTED" "$ACTUAL"
+
+    # Test non numerical values
+    EXPECTED="'v' requires numeric values"
+    ACTUAL=$("$PROGRAM" -e '[ foo ] v' 2>&1) || true
+    assert_eq "$EXPECTED" "$ACTUAL"
+
+    # Test domain error
+    EXPECTED="'v' domain error"
+    ACTUAL=$("$PROGRAM" -e '-1 v' 2>&1) || true
+    assert_eq "$EXPECTED" "$ACTUAL"
+}
+# vim: ts=4 sw=4 softtabstop=4 expandtab: