From 198f084f5dbb2cd9cec986b11a05518532fcc1a8 Mon Sep 17 00:00:00 2001
From: Enno Rehling <enno.rehling@gmail.com>
Date: Wed, 27 Dec 2017 21:54:09 +0100
Subject: [PATCH] implement speedy ships, with unit tests and edge testing.

---
 scripts/tests/e2/ships.lua |  9 ++-------
 src/kernel/ship.c          | 24 ++++++++++++++++++++----
 src/kernel/ship.test.c     | 15 +++++++++++++--
 3 files changed, 35 insertions(+), 13 deletions(-)

diff --git a/scripts/tests/e2/ships.lua b/scripts/tests/e2/ships.lua
index 625e62f64..ba410a56b 100644
--- a/scripts/tests/e2/ships.lua
+++ b/scripts/tests/e2/ships.lua
@@ -58,25 +58,20 @@ function test_speedy_ship_slow()
     u2:set_skill("sailing", 24) -- sumskill = 50
     u1.name = "XXX"
     u1:add_order("NACH O O O O O O O O O O")
-    print(u1.region)
     process_orders()
-    print(u1.region)
     assert_equal(5, u1.region.x)
 end
 
 function test_speedy_ship_fast()
     local r1 = region.create(0, 0, 'ocean')
     local f = faction.create("human")
-    f.name="Vikings"
     local u1 = unit.create(f, r1, 1)
-    u1.name = "Hagar"
     for x = 1, 10 do
         region.create(x, 0, 'ocean')
     end
     u1.ship = ship.create(r1, "dragonship")
-    u1:set_skill("sailing", 64) -- cptskill = 2^6
+    u1:set_skill("sailing", 54) -- cptskill = 2*3^3
     u1:add_order("NACH O O O O O O O O O O")
     process_orders()
-    print(f, get_turn())
-    assert_equal(10, u1.region.x)
+    assert_equal(8, u1.region.x)
 end
diff --git a/src/kernel/ship.c b/src/kernel/ship.c
index 88eb5c39f..400e05a9d 100644
--- a/src/kernel/ship.c
+++ b/src/kernel/ship.c
@@ -288,12 +288,28 @@ const char *write_shipname(const ship * sh, char *ibuf, size_t size)
 
 static int ShipSpeedBonus(const unit * u)
 {
-    int level = config_get_int("movement.shipspeed.skillbonus", 0);
-    if (level > 0) {
-        ship *sh = u->ship;
+    const ship * sh = u->ship;
+    static int config;
+    static int bonus;
+
+    if (config_changed(&config)) {
+        bonus = config_get_int("movement.shipspeed.skillbonus", 0);
+    }
+    if (bonus > 0) {
         int skl = effskill(u, SK_SAILING, 0);
         int minsk = (sh->type->cptskill + 1) / 2;
-        return (skl - minsk) / level;
+        return (skl - minsk) / bonus;
+    }
+    else if (sh->type->flags & SFL_SPEEDY) {
+        int base = 3;
+        int speed = 0;
+        int minsk = sh->type->cptskill * base;
+        int skl = effskill(u, SK_SAILING, 0);
+        while (skl >= minsk) {
+            ++speed;
+            minsk *= base;
+        }
+        return speed;
     }
     return 0;
 }
diff --git a/src/kernel/ship.test.c b/src/kernel/ship.test.c
index 280c2122a..f36ce28e2 100644
--- a/src/kernel/ship.test.c
+++ b/src/kernel/ship.test.c
@@ -438,7 +438,7 @@ static void test_shipspeed_speedy(CuTest *tc) {
     unit *cap, *crw;
     test_setup();
     stype = test_create_shiptype("dragonship");
-    stype->range = 2;
+    stype->range = 5;
     stype->range_max = -1;
     stype->flags |= SFL_SPEEDY;
     cap = test_create_unit(test_create_faction(NULL), test_create_region(0, 0, NULL));
@@ -449,7 +449,18 @@ static void test_shipspeed_speedy(CuTest *tc) {
     set_level(cap, SK_SAILING, stype->cptskill);
     set_level(crw, SK_SAILING, stype->sumskill - stype->cptskill);
     CuAssertPtrEquals(tc, cap, ship_owner(sh));
-    CuAssertIntEquals(tc, 2, shipspeed(sh, cap));
+    CuAssertIntEquals(tc, 5, shipspeed(sh, cap));
+
+    set_level(cap, SK_SAILING, stype->cptskill * 3 - 1);
+    CuAssertIntEquals(tc, 5, shipspeed(sh, cap));
+    set_level(cap, SK_SAILING, stype->cptskill * 3);
+    CuAssertIntEquals(tc, 6, shipspeed(sh, cap));
+
+    set_level(cap, SK_SAILING, stype->cptskill * 3 * 3 - 1);
+    CuAssertIntEquals(tc, 6, shipspeed(sh, cap));
+    set_level(cap, SK_SAILING, stype->cptskill * 3 * 3);
+    CuAssertIntEquals(tc, 7, shipspeed(sh, cap));
+
     test_teardown();
 }