Add tests for damage per second

tests/effective_dps_test.cpp

@@ -0,0 +1,163 @@
+#include <cstdlib>
+
+#include "avatar.h"
+#include "calendar.h"
+#include "creature.h"
+#include "game.h"
+#include "item.h"
+#include "player.h"
+#include "type_id.h"
+
+#include "catch/catch.hpp"
+#include "player_helpers.h"
+
+// Run a large number of trials of a player attacking a monster with a given weapon,
+// and return the average damage done per second.
+static double weapon_dps_trials( avatar &attacker, monster &defender, item &weapon )
+{
+    constexpr int trials = 1000;
+
+    int total_damage = 0;
+    int total_moves = 0;
+
+    clear_character( attacker );
+    REQUIRE( attacker.can_wield( weapon ).success() );
+    REQUIRE( attacker.wield( weapon ) );
+
+    // FIXME: This is_wielding check always fails
+    //REQUIRE( attacker.is_wielding( weapon ) );
+
+    for( int i = 0; i < trials; i++ ) {
+        // Keep track of attacker's moves and defender's HP
+        const int before_moves = attacker.get_moves();
+        const int starting_hp = defender.get_hp();
+        // Attack once
+        attacker.melee_attack( defender, false );
+        // Tally total damage and moves
+        total_damage += std::max( 0, starting_hp - defender.get_hp() );
+        total_moves += std::abs( attacker.get_moves() - before_moves );
+        // Reset for the next attack
+        attacker.empty_skills();        // Don't learn
+        defender.set_hp( starting_hp ); // Don't die
+    }
+
+    // Scale damage-per-move to damage-per-second
+    // 1 second == 100 moves
+    return 100.0f * total_damage / total_moves;
+}
+
+static void check_actual_dps( avatar &attacker, monster &defender, item &weapon )
+{
+    clear_character( attacker );
+    double expect_dps = weapon.effective_dps( attacker, defender );
+    double actual_dps = weapon_dps_trials( attacker, defender, weapon );
+    CHECK( actual_dps == Approx( expect_dps ).margin( 0.01f ) );
+}
+
+TEST_CASE( "effective damage per second", "[effective][dps]" )
+{
+    avatar &dummy = g->u;
+    clear_character( dummy );
+
+    item rock( "test_rock" );
+    item plank( "test_2x4" );
+    item knife( "knife_trench" );
+
+    SECTION( "against a debug monster with no armor or dodge" ) {
+        monster mummy( mtype_id( "debug_mon" ) );
+
+        CHECK( plank.effective_dps( dummy, mummy ) == Approx( 4.79f ).margin( 0.01f ) );
+        CHECK( knife.effective_dps( dummy, mummy ) == Approx( 20.16f ).margin( 0.01f ) );
+    }
+
+    SECTION( "against an agile target" ) {
+        monster smoker( mtype_id( "mon_zombie_smoker" ) );
+        REQUIRE( smoker.get_dodge() >= 4 );
+
+        CHECK( plank.effective_dps( dummy, smoker ) == Approx( 2.51f ).margin( 0.01f ) );
+        CHECK( knife.effective_dps( dummy, smoker ) == Approx( 10.57f ).margin( 0.01f ) );
+    }
+
+    SECTION( "against an armored target" ) {
+        monster soldier( mtype_id( "mon_zombie_soldier" ) );
+
+        CHECK( plank.effective_dps( dummy, soldier ) == Approx( 1.11f ).margin( 0.01f ) );
+        CHECK( knife.effective_dps( dummy, soldier ) == Approx( 2.22f ).margin( 0.01f ) );
+    }
+
+    SECTION( "effect of STR and DEX on damage per second" ) {
+        monster mummy( mtype_id( "debug_mon" ) );
+
+        SECTION( "STR 6, DEX 6" ) {
+            dummy.str_max = 6;
+            dummy.dex_max = 6;
+
+            CHECK( rock.effective_dps( dummy, mummy ) == Approx( 6.55f ).margin( 0.01f ) );
+            CHECK( plank.effective_dps( dummy, mummy ) == Approx( 3.60f ).margin( 0.01f ) );
+            CHECK( knife.effective_dps( dummy, mummy ) == Approx( 16.66f ).margin( 0.01f ) );
+        }
+
+        SECTION( "STR 8, DEX 8" ) {
+            dummy.str_max = 8;
+            dummy.dex_max = 8;
+
+            CHECK( rock.effective_dps( dummy, mummy ) == Approx( 8.84f ).margin( 0.01f ) );
+            CHECK( plank.effective_dps( dummy, mummy ) == Approx( 4.79f ).margin( 0.01f ) );
+            CHECK( knife.effective_dps( dummy, mummy ) == Approx( 20.16f ).margin( 0.01f ) );
+        }
+
+        SECTION( "STR 10, DEX 10" ) {
+            dummy.str_max = 10;
+            dummy.dex_max = 10;
+
+            CHECK( rock.effective_dps( dummy, mummy ) == Approx( 10.42f ).margin( 0.01f ) );
+            CHECK( plank.effective_dps( dummy, mummy ) == Approx( 5.55f ).margin( 0.01f ) );
+            CHECK( knife.effective_dps( dummy, mummy ) == Approx( 21.61f ).margin( 0.01f ) );
+        }
+    }
+}
+
+TEST_CASE( "effective vs actual damage per second", "[actual][dps][!mayfail]" )
+{
+    avatar &dummy = g->u;
+    clear_character( dummy );
+
+    monster mummy( mtype_id( "debug_mon" ) );
+    monster soldier( mtype_id( "mon_zombie_soldier" ) );
+    monster smoker( mtype_id( "mon_zombie_smoker" ) );
+    monster survivor( mtype_id( "mon_zombie_survivor" ) );
+
+    item rock( "test_rock" );
+    item plank( "test_2x4" );
+    item knife( "knife_trench" );
+    item halligan( "test_halligan" );
+
+    SECTION( "debug monster" ) {
+        check_actual_dps( dummy, mummy, rock );
+        check_actual_dps( dummy, mummy, plank );
+        check_actual_dps( dummy, mummy, knife );
+        check_actual_dps( dummy, mummy, halligan );
+    }
+
+    SECTION( "soldier zombie" ) {
+        check_actual_dps( dummy, soldier, rock );
+        check_actual_dps( dummy, soldier, plank );
+        check_actual_dps( dummy, soldier, knife );
+        check_actual_dps( dummy, soldier, halligan );
+    }
+
+    SECTION( "smoker zombie" ) {
+        check_actual_dps( dummy, smoker, rock );
+        check_actual_dps( dummy, smoker, plank );
+        check_actual_dps( dummy, smoker, knife );
+        check_actual_dps( dummy, smoker, halligan );
+    }
+
+    SECTION( "survivor zombie" ) {
+        check_actual_dps( dummy, survivor, rock );
+        check_actual_dps( dummy, survivor, plank );
+        check_actual_dps( dummy, survivor, knife );
+        check_actual_dps( dummy, survivor, halligan );
+    }
+}
+