Improve BigInt hashing (#38)

Fixes: https://github.com/quickjs-ng/quickjs/issues/35

quickjs.c

@@ -43301,6 +43301,7 @@ static uint32_t map_hash_key(JSContext *ctx, JSValueConst key)
     uint32_t h;
     double d;
     JSFloat64Union u;
+    bf_t *a;
 
     switch(tag) {
     case JS_TAG_BOOL:
@@ -43316,6 +43317,10 @@ static uint32_t map_hash_key(JSContext *ctx, JSValueConst key)
     case JS_TAG_INT:
         d = JS_VALUE_GET_INT(key) * 3163;
         goto hash_float64;
+    case JS_TAG_BIG_INT:
+        a = JS_GetBigInt(key);
+        h = hash_string8((void *)a->tab, a->len * sizeof(*a->tab), 0);
+        break;
     case JS_TAG_FLOAT64:
         d = JS_VALUE_GET_FLOAT64(key);
         /* normalize the NaN */
@@ -43326,7 +43331,7 @@ static uint32_t map_hash_key(JSContext *ctx, JSValueConst key)
         h = (u.u32[0] ^ u.u32[1]) * 3163;
         break;
     default:
-        h = 0; /* XXX: bigint support */
+        h = 0;
         break;
     }
     h ^= tag;

tests/test_bigint.js

@@ -110,5 +110,30 @@ function test_bigint2()
     assertThrows(SyntaxError, () => { BigInt("  123  r") } );
 }
 
+function test_bigint_map()
+{
+    var m = new Map();
+    assert(m.size, 0);
+
+    for (let i = 0n; i < 1337n; i++) {
+        const r = m.set(i, i.toString());
+        assert(r, m);
+    }
+    assert(m.size, 1337);
+
+    for (let i = 0n; i < 1337n; i++) {
+        const r = m.get(i);
+        assert(r, i.toString());
+    }
+    assert(m.get(1337n), undefined);
+    assert(m.size, 1337);
+
+    for (let i = 0n; i < 1337n; i++)
+        assert(m.delete(i));
+    assert(!m.delete(1337n));
+    assert(m.size, 0);
+}
+
 test_bigint1();
 test_bigint2();
+test_bigint_map();