add hashmap add len list

test/collection/test_hashmap.scad

@@ -0,0 +1,28 @@
+use <unittest.scad>;
+use <collection/hashmap.scad>;
+use <collection/hashmap_list.scad>;
+use <collection/hashmap_add.scad>;
+use <collection/hashmap_len.scad>;
+
+module test_hashmap() {
+    echo("==== test_hashmap ====");
+
+    s = hashmap([
+        ["k1234", 1],
+        ["k5678", 2],
+        ["k9876", 3],
+        ["k4444", 3],
+    ]);
+
+    assert(hashmap_len(s) == 4);
+
+    assert(hashmap_list(s) == [["k9876", 3], ["k4444", 3], ["k1234", 1], ["k5678", 2]]);
+    
+    s2 = hashmap_add(s, "k1357", 100);
+    assert(hashmap_list(s2) == [["k9876", 3], ["k4444", 3], ["k1234", 1], ["k5678", 2], ["k1357", 100]]);
+
+    s3 = hashmap_add(s2, "k5678", 200);
+    assert(hashmap_list(s3) == [["k9876", 3], ["k4444", 3], ["k1234", 1], ["k5678", 200], ["k1357", 100]]);
+}
+
+test_hashmap();