Add exact arithmetic implementation and tests

- Introduced exact arithmetic with support for large integers and fractions in `exact.gd`, `big_integer.gd`, and `exact_value.gd`. - Implemented a comprehensive test suite in `test_exact_math.gd` to validate arithmetic operations against expected results. - Added a README in `math` directory to document the exact arithmetic system and its usage. - Ensured that all arithmetic operations maintain precision without floating-point errors, using a custom representation for large numbers. - Included methods for encoding and decoding exact values for serialization.
2026-09-30 08:08:27 +03:00
parent f2111a376a
commit fb8a3f5658
58 changed files with 5139 additions and 2162 deletions
@@ -0,0 +1,76 @@
+extends SceneTree
+
+const E = preload("res://world/owniverse/math/exact.gd")
+const Q = preload("res://world/owniverse/quantity_math.gd")
+const Clock = preload("res://world/owniverse/simulation_time.gd")
+var checks: int = 0
+var failures: int = 0
+
+func _initialize():
+    call_deferred("run")
+
+func check(actual, expected: String, label: String):
+    checks += 1
+    if str(actual) != expected:
+        failures += 1
+        push_error(label + ": " + str(actual) + " != " + expected)
+
+func run():
+    # Expected strings were generated independently with Python fractions.Fraction.
+    var cases = JSON.parse_string(FileAccess.get_file_as_string("res://tests/fixtures/exact_oracle.json"))
+    for row in cases:
+        var a = E.of(row[0])
+        var b = E.of(row[1])
+        check(E.add(a, b), row[2], "sum")
+        check(E.subtract(a, b), row[3], "difference")
+        check(E.multiply(a, b), row[4], "product")
+        check(E.divide(a, b), row[5], "quotient")
+        check(E.floor_value(E.divide(a, b)), row[6], "floor")
+    for text in ["9223372036854775807", "-9223372036854775808", "9007199254740993", "1000000000000000000000000001", "-1/10000000000000"]:
+        var value = E.of(text)
+        check(E.decode(JSON.parse_string(JSON.stringify(E.encode(value)))), text, "JSON round trip")
+    check(E.add(E.of("9223372036854775807"), 1), "9223372036854775808", "int64 overflow promoted")
+    check(E.subtract(E.of("-9223372036854775808"), 1), "-9223372036854775809", "int64 underflow promoted")
+    check(Q.production_step([E.of("1e27")]), "1", "large integral recipe")
+    check(Q.production_step([E.of("1e-13")]), "10000000000000", "tiny fractional recipe")
+    var count = E.of("1000000000000000000000000001")
+    var allocation = Q.allocate_whole({"a": count, "b": count, "c": count}, count)
+    check(Q.sum(allocation), str(count), "allocation conserves every unit")
+    check(allocation.a, "333333333333333333333333334", "deterministic remainder")
+    var clock = Clock.advance({"datetime": E.of("1e27")}, 0.000000001, 1)
+    check(E.subtract(clock.datetime, E.of("1e27")), "1/1000000000", "single tick at huge age")
+    var world = load("res://world/owniverse/owniverse.gd").new()
+    world.catalog.load_definitions(root.get_node("Global").OwniverseEntities)
+    for id in world.catalog.entities:
+        world.state.amount[id] = 0
+        world.state.stats.total_amount[id] = 0
+        var group: String = world.catalog.entities[id].group_as
+        if group != "":
+            world.state.amount[group] = 0
+            world.state.stats.total_amount[group] = 0
+    world.production.produce_hs("H", 1)
+    check(world.state.energy, "999999999999999999999999999", "spend one energy")
+    var life = world.life.life_products(world.state, world.catalog.entities.EON5, count)
+    check(Q.sum(life), str(count), "life conservation at 1e27")
+    var precise = E.divide(count, E.of("100000000000000000000000000000000000003"))
+    var bounded = E.bounded(precise)
+    check(E.lt(E.absolute(E.subtract(precise, bounded)), E.of("1e-36")), "true", "bounded fractional error")
+    check(E.bounded(count), str(count), "integer counts never quantized")
+    world.state.amount.S = E.of("1e24")
+    world.state.amount.H = E.of("1e24")
+    world.state.amount.RD = 1234567
+    world.state.amount.YD = 765432
+    world.state.amount.STN = 654321
+    world.speed = 6
+    var started: int = Time.get_ticks_msec()
+    for i in 100:
+        world.state.amount.RD = E.add(world.state.amount.RD, i + 1)
+        world.evolute(0.1)
+        check(str(world.state.auto_star_deficits).length() < 500, "true", "fraction storage stays bounded")
+    print("100 changing-composition cycles: %d ms" % (Time.get_ticks_msec() - started))
+    var saves = root.get_node("SaveManager")
+    check(saves.validate_data({"format_version": 3, "app_version": "", "ui": {"current_page": 0}, "state": world.state}), "", "long-running state saves")
+    for entity in world.catalog.entities.values(): entity.free()
+    world.free()
+    print("Exact math: %d checks, %d failures" % [checks, failures])
+    quit(0 if failures == 0 else 1)