Merge pull request #62 from rdewilder/buyramburn

contracts/eosio.system/include/eosio.system/eosio.system.hpp

@@ -1209,6 +1209,17 @@ namespace eosiosystem {
  [[eosio::action]]
  action_return_ramtransfer ramburn( const name& owner, int64_t bytes, const std::string& memo );
 
+ /**
+ * Buy RAM and immediately burn RAM.
+ * An inline transfer from payer to system contract of tokens will be executed.
+ *
+ * @param payer - the payer of buy RAM & burn.
+ * @param quantity - the quantity of tokens to buy RAM & burn with.
+ * @param memo - the memo string to accompany the transaction.
+ */
+ [[eosio::action]]
+ action_return_buyram buyramburn( const name& payer, const asset& quantity, const std::string& memo );
+
  /**
  * Logging for ram changes
  *
@@ -1522,6 +1533,7 @@ namespace eosiosystem {
  using logsellram_action = eosio::action_wrapper<"logsellram"_n, &system_contract::logsellram>;
  using ramtransfer_action = eosio::action_wrapper<"ramtransfer"_n, &system_contract::ramtransfer>;
  using ramburn_action = eosio::action_wrapper<"ramburn"_n, &system_contract::ramburn>;
+ using buyramburn_action = eosio::action_wrapper<"buyramburn"_n, &system_contract::buyramburn>;
  using logramchange_action = eosio::action_wrapper<"logramchange"_n, &system_contract::logramchange>;
  using refund_action = eosio::action_wrapper<"refund"_n, &system_contract::refund>;
  using regproducer_action = eosio::action_wrapper<"regproducer"_n, &system_contract::regproducer>;

contracts/eosio.system/ricardian/eosio.system.contracts.md.in

@@ -454,6 +454,21 @@ Burn {{bytes}} bytes of unused RAM from account {{owner}}.
 {{memo}}
 {{/if}}
 
+<h1 class="contract">buyramburn</h1>
+
+---
+spec_version: "0.2.0"
+title: Buy and Burn RAM
+summary: 'Buy and immediately Burn {{quantity}} of RAM from {{nowrap payer}}'
+icon: @ICON_BASE_URL@/@RESOURCE_ICON_URI@
+---
+
+Buy and Burn {{quantity}} of RAM from account {{payer}}.
+
+{{#if memo}}There is a memo attached to the action stating:
+{{memo}}
+{{/if}}
+
 <h1 class="contract">sellrex</h1>
 
 ---

contracts/eosio.system/src/delegate_bandwidth.cpp

@@ -179,6 +179,20 @@ namespace eosiosystem {
  return ramtransfer( owner, null_account, bytes, memo );
  }
 
+ /**
+ * This action will buy and then burn the purchased RAM bytes.
+ */
+ action_return_buyram system_contract::buyramburn( const name& payer, const asset& quantity, const std::string& memo ) {
+ require_auth( payer );
+ check( quantity.symbol == core_symbol(), "quantity must be core token" );
+ check( quantity.amount > 0, "quantity must be positive" );
+
+ const auto return_buyram = buyram( payer, payer, quantity );
+ ramburn( payer, return_buyram.bytes_purchased, memo );
+
+ return return_buyram;
+ }
+
  [[eosio::action]]
  void system_contract::logramchange( const name& owner, int64_t bytes, int64_t ram_bytes )
  {

tests/eosio.system_ram_tests.cpp

@@ -161,6 +161,31 @@ BOOST_FIXTURE_TEST_CASE( ram_burn, eosio_system_tester ) try {
 
 } FC_LOG_AND_RETHROW()
 
+// buyramburn
+BOOST_FIXTURE_TEST_CASE( buy_ram_burn, eosio_system_tester ) try {
+ const std::vector<account_name> accounts = { "alice"_n };
+ const account_name alice = accounts[0];
+ const account_name null_account = "eosio.null"_n;
+
+ create_accounts_with_resources( accounts );
+ transfer( config::system_account_name, alice, core_sym::from_string("100.0000"), config::system_account_name );
+
+ BOOST_REQUIRE_EQUAL( success(), buyrambytes( alice, alice, 10000 ) );
+ BOOST_REQUIRE_EQUAL( success(), buyrambytes( alice, null_account, 10000 ) );
+
+ const uint64_t null_before_buyramburn = get_total_stake( null_account )["ram_bytes"].as_uint64();
+ const uint64_t alice_before_buyramburn = get_total_stake( alice )["ram_bytes"].as_uint64();
+ const asset initial_alice_balance = get_balance(alice);
+ const asset ten_core_token = core_sym::from_string("10.0000");
+
+ // buy ram burn action
+ BOOST_REQUIRE_EQUAL( success(), buyramburn( alice, ten_core_token, "burn RAM burn memo" ) );
+ const uint64_t alice_after_buyramburn = get_total_stake( alice )["ram_bytes"].as_uint64();
+ const uint64_t null_after_buyramburn = get_total_stake( null_account )["ram_bytes"].as_uint64();
+ BOOST_REQUIRE_EQUAL( alice_before_buyramburn, alice_after_buyramburn );
+ BOOST_REQUIRE_EQUAL( true, null_before_buyramburn < null_after_buyramburn );
+ BOOST_REQUIRE_EQUAL( initial_alice_balance - ten_core_token, get_balance(alice));
+} FC_LOG_AND_RETHROW()
 
 // buyramself
 BOOST_FIXTURE_TEST_CASE( buy_ram_self, eosio_system_tester ) try {

tests/eosio.system_tester.hpp

@@ -428,6 +428,11 @@ class eosio_system_tester : public TESTER {
  return ramburn(account_name(owner), bytes, memo);
  }
 
+ action_result buyramburn( const name& payer, const asset& quantity, const std::string& memo)
+ {
+ return push_action(payer, "buyramburn"_n, mvo()("payer", payer)("quantity", quantity)("memo", memo));
+ }
+
  void validate_ramburn_return(const account_name& owner, uint32_t bytes, const std::string& memo,
  const type_name& type, const std::string& json) {
  // create hex return from provided json