Resurrect tests from deleted bigint_operations_test.cc into new bigint_test.cc

runtime/vm/object.cc

 // Copyright (c) 2012, 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/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/cpu.h"
@@ skipping 16514 matching lines @@
   }
   intptr_t str_pos = 0;
 
   Bigint& result = Bigint::Handle(Bigint::New(space));
   // One decimal digit takes log2(10) bits, i.e. ~3.32192809489 bits.
   // That is a theoretical limit for large numbers.
   // The extra digits allocated take care of variations (kExtraDigits).
   const int64_t kLog10Dividend = 33219281;
   const int64_t kLog10Divisor = 10000000;
   result.EnsureLength((kLog10Dividend * str_length) /
-                      (kLog10Divisor * kBitsPerDigit), space);
+                      (kLog10Divisor * kBitsPerDigit) + 1, space);
 
   // Read first digit separately. This avoids a multiplication and addition.
   // The first digit might also not have kDecDigitsPerIteration decimal digits.
   const intptr_t lsdigit_length = str_length % kDecDigitsPerIteration;
   uint32_t digit = 0;
   for (intptr_t i = 0; i < lsdigit_length; i++) {
     char c = str[str_pos++];
     ASSERT(('0' <= c) && (c <= '9'));
     digit = digit * 10 + c - '0';
   }
@@ skipping 3806 matching lines @@
   return tag_label.ToCString();
 }
 
 
 void UserTag::PrintJSONImpl(JSONStream* stream, bool ref) const {
   Instance::PrintJSONImpl(stream, ref);
 }
 
 
 }  // namespace dart