Add methods for creating Bigint objects from unsigned 64-bit integers.

runtime/vm/bigint_operations_test.cc

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/assert.h"
 #include "vm/bigint_operations.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
 #include "vm/unit_test.h"
 
@@ skipping 82 matching lines @@
   big = BigintOperations::NewFromInt64(kMaxValue64);
   EXPECT(BigintOperations::FitsIntoInt64(big));
   back = BigintOperations::ToInt64(big);
   EXPECT_EQ(kMaxValue64, back);
 
   big = BigintOperations::Add(big, one);
   EXPECT(!BigintOperations::FitsIntoInt64(big));
 }
 
 
+TEST_CASE(BigintUInt64) {
+  const uint64_t kMax =
+      static_cast<uint64_t>(DART_2PART_UINT64_C(0xFFFFFFFF, FFFFFFFF));
+
+  const Bigint& one = Bigint::Handle(BigintOperations::NewFromUInt64(1));
+  EXPECT(BigintOperations::FitsIntoInt64(one));
+  EXPECT(BigintOperations::FitsIntoUInt64(one));
+
+  Bigint& big = Bigint::Handle(BigintOperations::NewFromUInt64(kMax));
+  EXPECT(!BigintOperations::FitsIntoInt64(big));
+  EXPECT(BigintOperations::FitsIntoUInt64(big));
+
+  uint64_t back = BigintOperations::ToUInt64(big);
+  EXPECT_EQ(kMax, back);
+
+  big = BigintOperations::Add(big, one);
+  EXPECT(!BigintOperations::FitsIntoInt64(big));
+  EXPECT(!BigintOperations::FitsIntoUInt64(big));
+
+  big = BigintOperations::Subtract(big, one);
+  EXPECT(!BigintOperations::FitsIntoInt64(big));
+  EXPECT(BigintOperations::FitsIntoUInt64(big));
+
+  big = BigintOperations::ShiftRight(big, 1);
+  EXPECT(BigintOperations::FitsIntoInt64(big));
+  EXPECT(BigintOperations::FitsIntoUInt64(big));
+}
+
+
 TEST_CASE(BigintDouble) {
   Smi& smi = Smi::Handle(Smi::New(5));
   Bigint& bigint = Bigint::Handle(BigintOperations::NewFromSmi(smi));
   Double& dbl = Double::Handle(BigintOperations::ToDouble(bigint));
   EXPECT_EQ(5.0, dbl.value());
 
   smi = Smi::New(0);
   bigint = BigintOperations::NewFromSmi(smi);
   dbl = BigintOperations::ToDouble(bigint);
   EXPECT_EQ(0.0, dbl.value());
@@ skipping 1988 matching lines @@
       "123456789012345678901234567890123456789012345678901234567890123456789012"
       "345678901234567890123456789012345678901234567890123456789012345678901234"
       "567890123456789012345678901234567890123456789012345678901234567890123456"
       "789012345678901234567890123456789012345678901234567890123456789012345678"
       "90123456789012345678901234567890",
       "0x1234567890ABCDEF01234567890ABCDEF01234567890ABCDEF01234567890ABCDEF"
       "01234567890ABCDEE");
 }
 
 }  // namespace dart