diff --git a/tests/item_group_test.cpp b/tests/item_group_test.cpp
index 2e4873473796a..e35557d45071d 100644
--- a/tests/item_group_test.cpp
+++ b/tests/item_group_test.cpp
@@ -2,11 +2,62 @@
 #include "item.h"
 #include "item_group.h"
 
-TEST_CASE( "spawn tool with default charges and ammo setting" )
+TEST_CASE( "spawn with default charges and with ammo", "[item_group]" )
 {
     Item_modifier default_charges;
     default_charges.with_ammo = 100;
-    item matches( "matches" );
-    matches.charges = 0;
-    default_charges.modify( matches );
+    SECTION( "tools without ammo" ) {
+        item matches( "matches" );
+        REQUIRE( matches.ammo_default() == "NULL" );
+        default_charges.modify( matches );
+        CHECK( matches.ammo_remaining() == matches.ammo_capacity() );
+    }
+
+    SECTION( "gun with ammo type" ) {
+        item glock( "glock_19" );
+        REQUIRE( glock.ammo_default() != "NULL" );
+        default_charges.modify( glock );
+        CHECK( glock.ammo_remaining() == glock.ammo_capacity() );
+    }
+}
+
+TEST_CASE( "Item_modifier damages item", "[item_group]" )
+{
+    Item_modifier damaged;
+    damaged.damage.first = 1;
+    damaged.damage.second = 1;
+    SECTION( "except when it's an ammunition" ) {
+        item rock( "rock" );
+        REQUIRE( rock.damage() == 0 );
+        REQUIRE( rock.max_damage() == 0 );
+        damaged.modify( rock );
+        CHECK( rock.damage() == 0 );
+    }
+    SECTION( "when it can be damaged" ) {
+        item glock( "glock_19" );
+        REQUIRE( glock.damage() == 0 );
+        REQUIRE( glock.max_damage() > 0 );
+        damaged.modify( glock );
+        CHECK( glock.damage() == 1 );
+    }
+}
+
+TEST_CASE( "Item_modifier gun fouling", "[item_group]" )
+{
+    Item_modifier fouled;
+    fouled.dirt.first = 1;
+    SECTION( "guns can be fouled" ) {
+        item glock( "glock_19" );
+        REQUIRE( !glock.has_flag( "PRIMITIVE_RANGED_WEAPON" ) );
+        REQUIRE( !glock.has_var( "dirt" ) );
+        fouled.modify( glock );
+        CHECK( glock.get_var( "dirt", 0.0 ) > 0.0 );
+    }
+    SECTION( "bows can't be fouled" ) {
+        item bow( "longbow" );
+        REQUIRE( !bow.has_var( "dirt" ) );
+        REQUIRE( bow.has_flag( "PRIMITIVE_RANGED_WEAPON" ) );
+        fouled.modify( bow );
+        CHECK( !bow.has_var( "dirt" ) );
+    }
 }