Commit graph

491 commits

Author SHA1 Message Date
Roman Khimov
10601cb375 core: add issuer hashes into the verification list for Issue TX
As it should be done.
2020-03-17 11:40:00 +03:00
Roman Khimov
dca637d2d0 core: add owner hash to verified list for Register TX
As it should be done.
2020-03-17 11:37:02 +03:00
Roman Khimov
77a799f7d0 core: add missing state tx verifications 2020-03-16 20:14:59 +03:00
Roman Khimov
6ede65610d core: add appropriate hashes to check for State TX
These checks are important for proper transaction verification.
2020-03-16 19:52:28 +03:00
Evgenii Stratonikov
b193e78def core: remove duplication from IsDoubleClaim/IsDoubleSpend 2020-03-16 14:11:19 +03:00
Evgenii Stratonikov
cdf025bf89 transaction: implement AddVerificationHash() method 2020-03-16 14:11:19 +03:00
Roman Khimov
e9429374aa
Merge pull request #756 from nspcc-dev/feature/unclaimed
core/state: do not unmarshal Unclaimed balances in account
2020-03-16 13:21:23 +03:00
Evgenii Stratonikov
e503d1001d core/state: do not unmarshal Unclaimed balances in account 2020-03-16 12:19:32 +03:00
Roman Khimov
e6e8761d35 core: fix contract's state migration and don't swallow errors
Fixes difference in state changes at mainnet's block 2442790 because contract
migration in b4eb2dc35226e6520ee4e09a56197dff91547b50a7f57edc82930fc18c75dffc
doesn't actually transfer the storage state, it only deletes the old one.

And add an error check just in case.
2020-03-16 11:52:09 +03:00
Roman Khimov
d9a83373ed
Merge pull request #748 from nspcc-dev/feature/splitnep5
core: store NEP5 balances separately from account
2020-03-12 18:31:25 +03:00
Evgenii Stratonikov
ac475940a0 core: cache NEP5Transfers in cached DAO 2020-03-12 17:16:11 +03:00
Evgenii Stratonikov
6fa2a998f4 core: cache NEP5Balances in cached DAO 2020-03-12 17:06:20 +03:00
Evgenii Stratonikov
32401a567e core: store NEP5Transfers in batches
This is an append-only log which is read only during some RPCs.
It is rather slow to get it from base every time we need to append to
it. This commit stores all NEP5Transfers in batches, so that
only a last batch needs to be unmarshaled during block processing.
2020-03-12 14:51:12 +03:00
Evgenii Stratonikov
3c6d9653b0 core/state: add Size() method to NEP5TransferLog 2020-03-12 12:58:30 +03:00
Evgenii Stratonikov
df2598c8dc core: store NEP5 balances separately
There is no need to take and unmarshal an account structure only
to get it's NEP5 balances.
2020-03-12 12:58:28 +03:00
Roman Khimov
bbd802681e cli: make gas parameter to deployment add gas to the base price
That's how it was intended to behave originally. One thing questionable here
is contract price (policy thing, basically) being moved to smartcontract
package, but it's probably fine for NEO 2.0 (as it won't change) and we'll
make something better for NEO 3.0.
2020-03-11 20:34:36 +03:00
Roman Khimov
5f1868af28
Merge pull request #743 from nspcc-dev/optimize-some-db-accesses
Optimize some db accesses
2020-03-11 17:33:36 +03:00
Roman Khimov
abd7855890
Merge pull request #742 from nspcc-dev/add-dynamic-appcall
vm: add support for dynamic invocations in APPCALL
2020-03-11 17:27:05 +03:00
Roman Khimov
8c902a7223 core: cache UnspentCoins in cachedDao
1.5M block import time (VerifyBlocks disabled) on AMD Ryzen 5 1600/16GB/HDD,
before:
real    159m16.551s
user    69m58.279s
sys     7m34.334s

after:
real    139m41.836s
user    67m12.477s
sys     6m19.420s

12% which is even a bit more than could be expected from inputs analysis (that
has around 10% cache hits for a block-wide cache), worth doing.
2020-03-11 12:40:02 +03:00
Roman Khimov
23464401bc core/state: merge spent and unspent coins state, use it to store more things
This change reduces pressure on DB by doing the following things:
 * not storing additional KV pair for SpentCoin
 * storing Output right in the UnspentCoin, thus eliminating the need to get a
   full transaction from DB

At the same time it makes UnspentCoin more fat and hot, but it should probably
worth it.

Also drop `GetUnspentCoinStateOrNew` as it shouldn't ever existed, UTXOs
can't come out of nowhere.

1.5M block import time (VerifyBlocks disabled) on AMD Ryzen 5 1600/16GB/HDD,
before:
real    302m9.895s
user    96m17.200s
sys     13m37.084s

after:
real    159m16.551s
user    69m58.279s
sys     7m34.334s

So it's almost two-fold which is a great improvement.
2020-03-11 12:40:02 +03:00
Roman Khimov
e1f194ea7b core: treat state.Coin as a bitfield
As it was intended to.
2020-03-11 12:22:57 +03:00
Roman Khimov
377fb382aa core: move (un)SpentCoin structs into the state package
As they're all about the state.
2020-03-11 12:22:52 +03:00
Roman Khimov
8318adac56 vm: add support for dynamic invocations in APPCALL
Fixes #740.
2020-03-10 17:17:36 +03:00
Evgenii Stratonikov
ebf867b11d state: add a test for NEP5Transfer size
It's size is used in NEP5TransferLog so we need to be
sure it reflects reality.
2020-03-10 13:02:14 +03:00
Roman Khimov
ee57b96566
Merge pull request #733 from nspcc-dev/fix-getreferences-interop-regression
Fix GetReferences interop regression
2020-03-10 10:27:36 +03:00
Roman Khimov
0e2bda4f21 core: drop txHash from SpentCoinState
It's a key for it, makes no sense storing it as data.
2020-03-09 16:58:21 +03:00
Roman Khimov
eb404ceae3 core: fix max contract description limit check
It differs from other parameters in C# code. Fixes #735.
2020-03-09 14:18:51 +03:00
Roman Khimov
4587121c7f core: fix error propagation in contract-related interops
Obvious bug that hides failed contract deployments.
2020-03-09 14:18:00 +03:00
Roman Khimov
4b83e9a5cd
Merge pull request #732 from nspcc-dev/feature/getvalidators
rpc: implement getvalidators
2020-03-07 21:43:38 +03:00
Anna Shaleva
456a2d55fd rpc: implement getvalidators
closes #714
2020-03-07 18:05:40 +03:00
Roman Khimov
baeaa3dbe6 core: optimize tx verification, only get references and results once
Getting references requires DB access and that is expensive.
2020-03-06 20:15:01 +03:00
Roman Khimov
fe4916f691 core: simplify GetTransactionResults() a bit
Make less movements.
2020-03-06 19:26:39 +03:00
Roman Khimov
ced5ddbb9e core: fix wrong references ordering in interop function
Broken by 9f7018503a. Almost the same problem as
in 01082a8988 (though it is deterministic now,
just not the way the contract expects).
2020-03-06 19:20:55 +03:00
Roman Khimov
0e8ff558d1
Merge pull request #727 from nspcc-dev/fix-wrong-endian-in-interop-hashes
core: fix wrong endian used in interop functions
2020-03-06 19:07:28 +03:00
Roman Khimov
f8eee778f4
Merge pull request #724 from nspcc-dev/feature/submitblock
rpc: implement submitblock
2020-03-06 12:08:45 +03:00
Anna Shaleva
a746d8e6e6 rpc: implement submitblock RPC
closes #344
2020-03-06 12:03:08 +03:00
Evgenii Stratonikov
40188c5400 core: get rid of unnecessary copies
There is no need to keep Balances and Unclaimed slices
sorted, we need only to remove a single element.
2020-03-05 20:42:20 +03:00
Anna Shaleva
d3063c26e1 core: add custom error to blockhain.go
Add InvalidBlockIndex error to AddBlock func
2020-03-05 20:30:19 +03:00
Roman Khimov
a9abd3d841 core: fix wrong endian used in interop functions
C# uses ToArray() or UintXXX(bytes) here which interprets hashes as they
should be interpreted (BE, although they always convert to LE when converting
to String just for the fun of it). It leads to state difference for us at
block 2025204 where even though we have the same value for the key, the key
itself differs, ours:

dd2b538e2a0c1db1ae5061c15be14f916bd1e678e512ffcda6d9499d8e7fe97ee71fd6b8004583d9afe09cc4dadbd5deb63d01e061009b7cffdaa674beae0f930ebe6085af900093e5fe56b34a5c220ccdcf6efc336fc5000000000000000000000000000000000010

theirs:

dd2b538e2a0c1db1ae5061c15be14f916bd1e67861e0013db6ded5dbdac49ce0afd9834500b8d61fe77ee97f8e9d49d9a6cdff12e5009b7cffdaa674beae0f930ebe6085af900093e5fe56b34a5c220ccdcf6efc336fc5000000000000000000000000000000000010

In this key there is a tx hash encoded
(e512ffcda6d9499d8e7fe97ee71fd6b84583d9afe09cc4dadbd5deb63d01e061 in LE used
by all the tools like neoscan).

I love Neo.
2020-03-05 19:44:09 +03:00
Evgenii Stratonikov
95a8fa234f rpc: implement getnep5transfers RPC 2020-03-05 18:22:40 +03:00
Evgenii Stratonikov
6d270c4550 core,rpc: add NEP5 contract to testdata
Also transfer tokens between accounts.
2020-03-05 18:22:40 +03:00
Evgenii Stratonikov
f92fd3c948 core: track NEP5 transfers 2020-03-05 18:22:40 +03:00
Evgenii Stratonikov
e8c4179a9c core: track NEP5 balances 2020-03-05 18:22:19 +03:00
Evgenii Stratonikov
3a510b9dad core: allow transfer amount to be bytes
VM can produce both big.Int and []byte because they
are converted to each other on demand.
2020-03-05 15:18:38 +03:00
Roman Khimov
d03b2ef4a1
Merge pull request #706 from nspcc-dev/feature/transfer
cli: implement transfer from multisig accounts
2020-03-05 12:28:01 +03:00
Roman Khimov
5c781be08d
Merge pull request #718 from nspcc-dev/fix-invocation-tx-checks-and-fee
Fix Invocation TX checks and fee
2020-03-05 11:51:51 +03:00
Roman Khimov
9ac8001c7d core: protect (*Blockchain).keyCache with a lock
Avoid failures like this:
fatal error: concurrent map writes

goroutine 103 [running]:
runtime.throw(0xca6fe3, 0x15)
        /usr/lib64/go/1.12/src/runtime/panic.go:617 +0x72 fp=0xc000687988 sp=0xc000687958 pc=0x42d8d2
runtime.mapassign(0xb9d4a0, 0xc0000b1f80, 0xc000687a6c, 0x13bd940)
        /usr/lib64/go/1.12/src/runtime/map.go:590 +0x5e3 fp=0xc000687a10 sp=0xc000687988 pc=0x40e2a3
github.com/nspcc-dev/neo-go/pkg/core.(*Blockchain).verifyHashAgainstScript(0xc0000f8000, 0x1300d1f5a3d348be, 0x78607089e4fe9fab, 0xc0a21e4f71, 0xc000d16070, 0x1e2b8881f8178e92, 0xd589cfa965287bb8, 0x24a4e4f292ebc797, 0xb90d3120d878e619, 0xc0001d01e0, ...)
        /home/rik/dev/neo-go/pkg/core/blockchain.go:1866 +0x371 fp=0xc000687ad8 sp=0xc000687a10 pc=0x984ed1
github.com/nspcc-dev/neo-go/pkg/core.(*Blockchain).verifyHeaderWitnesses(0xc0000f8000, 0xc000d16000, 0xc00042d950, 0x1, 0xc00008a6c0)
        /home/rik/dev/neo-go/pkg/core/blockchain.go:1914 +0x209 fp=0xc000687c90 sp=0xc000687ad8 pc=0x985999
github.com/nspcc-dev/neo-go/pkg/core.(*Blockchain).verifyHeader(0xc0000f8000, 0xc000d16000, 0xc00042d950, 0xf0ee0049d611101f, 0xf8967398a8f9351b)
        /home/rik/dev/neo-go/pkg/core/blockchain.go:1254 +0x235 fp=0xc000687d70 sp=0xc000687c90 pc=0x97e4e5
github.com/nspcc-dev/neo-go/pkg/core.(*Blockchain).addHeaders(0xc0000f8000, 0x1, 0xc000d12000, 0x7d0, 0x7d0, 0x0, 0x1)
        /home/rik/dev/neo-go/pkg/core/blockchain.go:369 +0x266 fp=0xc000687e68 sp=0xc000687d70 pc=0x973f46
github.com/nspcc-dev/neo-go/pkg/core.(*Blockchain).AddHeaders(0xc0000f8000, 0xc000d12000, 0x7d0, 0x7d0, 0x0, 0xc0003640c0)
        /home/rik/dev/neo-go/pkg/core/blockchain.go:338 +0x51 fp=0xc000687eb0 sp=0xc000687e68 pc=0x973cb1
github.com/nspcc-dev/neo-go/pkg/network.(*Server).handleHeadersCmd(0xc00022c140, 0xdd0ca0, 0xc000374000, 0xc00000c020)
        /home/rik/dev/neo-go/pkg/network/server.go:431 +0x74 fp=0xc000687fc0 sp=0xc000687eb0 pc=0x9ce5e4
runtime.goexit()
        /usr/lib64/go/1.12/src/runtime/asm_amd64.s:1337 +0x1 fp=0xc000687fc8 sp=0xc000687fc0 pc=0x45ca51
created by github.com/nspcc-dev/neo-go/pkg/network.(*Server).handleMessage
        /home/rik/dev/neo-go/pkg/network/server.go:705 +0xa4a
...
2020-03-04 20:26:18 +03:00
Evgenii Stratonikov
7eaeb18f18 transaction: marshal ContractTX even if Data is nil
It contains no information so it doesn't matter anyway.
2020-03-04 20:01:26 +03:00
Evgenii Stratonikov
634e9483d3 transaction: unmarshal Witness properly
Both verification and invocation scripts need to
be unmarshaled from hex.
Also fix failing RPC tests: block contains non-pointer
`transaction.Witness` field and (*Witness).MarshalJSON method
is not called.
2020-03-04 20:01:26 +03:00
Evgenii Stratonikov
33f99104e8 transaction: unmarshal Output properly
Address is marshaled in base58 and needs to be
decoded accordingly.
2020-03-04 20:01:26 +03:00
Roman Khimov
81d89cd502 core: fix SystemFee calculation for Invocation TXes
They have it specified right in the transaction. Unfortunately, this little
change rendered invalid our RPC test chain, but I think it became even better
after it, especially given that chain generation is a nice test by itself, so
it should be running as a regular test.
2020-03-04 19:23:23 +03:00
Roman Khimov
ae6edf0601 core: add a check for fractional gas in invocation TXes
It's not allowed in C# code and that's reasonable as it's a sysfee essentially
that can only be integer.
2020-03-04 19:23:23 +03:00
Roman Khimov
823798514a util: rename Int64Value to IntegralValue, add FractionalValue
Makes it's interface more clear and allows to easily access fractional part.
2020-03-04 19:23:23 +03:00
Roman Khimov
7cc847d655 transaction: add some missing InvocationTX decoding checks
Script must have something inside and GAS can't be negative.
2020-03-04 19:23:23 +03:00
Roman Khimov
e41d434a49 *: move all packages from CityOfZion to nspcc-dev 2020-03-03 17:21:42 +03:00
Roman Khimov
59e6dac351
Merge pull request #708 from nspcc-dev/fix/trigger
core: convert trigger.Type to byte when pushing on stack
2020-03-03 16:17:01 +03:00
Evgenii Stratonikov
fe3bbbd78a core: convert trigger.Type to byte when pushing on stack 2020-03-03 16:13:19 +03:00
Roman Khimov
c3e73c5b7d core: don't reverify stale headers in addHeader
During networked synchronization we expect there to be a lot of duplicate
headers received and it makes no sense for us reverifying them.
2020-03-03 15:34:03 +03:00
Evgenii Stratonikov
05a3625b7d wallet: implement (*Account).SignTx
It is used in both CLI and RPC.
2020-03-02 18:03:56 +03:00
Evgenii Stratonikov
6add4f3e50 transaction: disallow negative outputs
Otherwise it is possible to make outputs which will sum
to the expected value, but steal GAS from some other account.
2020-03-02 18:01:49 +03:00
Evgenii Stratonikov
9e9d59b49a core: set NetworkFee to 0 for Claim and Miner transactions
Claim tx have no GAS inputs and a positive output which
can lead to negative network fee.
2020-03-02 18:01:49 +03:00
Evgenii Stratonikov
de5215a564 core: use GetAccountStateOrNew() in (*Blockchain).GetValidators()
Target of the transaction output may not yet exist in database.
2020-03-02 18:01:49 +03:00
Evgenii Stratonikov
1b9968df67 core: optimize CalculateClaimable()
Because accumulated system fee is stored for every block,
it is easy to calculate sum with just to reads.
2020-03-02 18:01:49 +03:00
Evgenii Stratonikov
258d8be1dd core: store all accumulated SystemFee with every block 2020-03-02 18:01:49 +03:00
Evgenii Stratonikov
f69c8a763b core: store system fee together with block
Recalculating system fee can be rather costly if done
frequently.
2020-03-02 18:01:49 +03:00
Evgenii Stratonikov
972e0d8ad1 core: add one more Contract tx to the test chain
When testing CLI it is useful to have some spent coins
on an account with a known key.
2020-03-02 18:01:49 +03:00
Evgenii Stratonikov
45b8669b42 core: verify Claim transactions 2020-03-02 18:01:49 +03:00
Evgenii Stratonikov
44792ed5f7 core: make test chain format compatible with mainnet
Write uint32 length before every block.
2020-03-02 18:01:49 +03:00
Evgenii Stratonikov
0e2a1f40ba core: add ContractTX to a testchain generator
Simple transfer from multisig account to the account
of one of the validators.
2020-03-02 18:00:00 +03:00
Evgenii Stratonikov
72d72296c3 core: implement (*Transaction).GetSignedPart()
Marshalling it and taking all but last byte violates incapsulation
and is just wrong in case transaction already contains any witnesses.
2020-03-02 18:00:00 +03:00
Evgenii Stratonikov
95d9f36c98 core: implement UnclaimedBalance tracking
To make it easy to get unclaimed coins for the
specified account they must be tracked together.
2020-03-02 18:00:00 +03:00
Evgenii Stratonikov
7095ec6c51 core: implement (*Blockchain).CalculateClaimable
Calculating amount of GAS that can be claimed is required
for getclaimable RPC.
2020-03-02 18:00:00 +03:00
Roman Khimov
252a9f2f31
Merge pull request #690 from nspcc-dev/feature/getapplicationlog
rpc: implement getapplicationlog RPC
2020-03-02 17:41:32 +03:00
Anna Shaleva
ff4384d7ff rpc: implement getapplicationlog RPC
Closes #500
2020-03-02 17:25:27 +03:00
Anna Shaleva
7d46404e2d smartcontract: turn trigger types into Type
1) Turn trigger types from byte constants into Type
2) Add auto-generated stringer for future purposes
2020-03-02 17:25:27 +03:00
Evgenii Stratonikov
a3dacd3b74 tests: replace t.Fatal with require where possible
This makes tests less verbose and unifies the style
they are written in.
2020-03-02 17:22:27 +03:00
Evgenii Stratonikov
66f96e3f32 core: shutdown Blockchain gracefully in tests 2020-03-02 17:22:27 +03:00
Evgenii Stratonikov
3a5224344e core: verify headers in AddHeaders()
Headers can be malformed so public methods should verify them
before adding.
2020-03-02 17:22:26 +03:00
Evgenii Stratonikov
357bb4ce41 core: get rid of global variables in tests
It can lead to unnecessary race conditions and is just
a bad practice.
2020-03-02 17:04:08 +03:00
Evgenii Stratonikov
8ca94e23c8 core: replace makeBlocks() with addBlocks() in tests
This simplifies tests a bit.
2020-03-02 17:04:08 +03:00
Evgenii Stratonikov
cbf26bac83 mempool: do not allocate new slice for verified transactions
Because transactions a iterated in an increasing order,
we can filter slice in-place.
2020-03-02 10:38:27 +03:00
Roman Khimov
3e2b490025 mempool: rework inputs verification, check Claim txes
Use more efficient check for Input and also check Claims to avoid double
claiming.
2020-02-27 13:43:35 +03:00
Roman Khimov
f329de73e8 mempool: fix Remove bug (dropping wrong tx!)
Uncovered by TestMemPoolAddRemoveWithInputsAndClaims (to be added later)
2020-02-27 13:43:35 +03:00
Roman Khimov
7d59fa0066
Merge pull request #696 from nspcc-dev/tx-verification-fixes
Claim and enrollment TX verification fixes
2020-02-27 12:45:36 +03:00
Roman Khimov
00d199ed85 core: fix NetworkFee calculation
Add doesn't change the variable state. Thanks to GolangCI for catching this.
2020-02-27 12:32:56 +03:00
Roman Khimov
7bea6e043e core: add double claim verification check 2020-02-27 12:32:56 +03:00
Roman Khimov
29586f2aa7 core: add duplicate Claim verification check
Refactor HaveInputsDuplicate() out of the core and Blockchain, it doesn't
depend on the Blockchain state. Make it more efficient.
2020-02-27 12:32:56 +03:00
Roman Khimov
9b1ad40273 core: drop GetScriptHashesForVerifyingClaim, fix Claim's ScriptHash getter
Claim transactions should _add_ claims scripthashes to the standard list, not
replace them. And this code is actually very reusable.
2020-02-27 12:32:56 +03:00
Roman Khimov
9f7018503a core/transaction: use new transaction.InOut for References
We don't need a map here, use simpler structures.
2020-02-27 12:00:03 +03:00
Roman Khimov
80de208a68 transaction: unbind GroupInputsByPrevHash from Transaction
Which allows to use it for ClaimTX. Make it also a bit more efficient as maps
are expensive.
2020-02-27 12:00:03 +03:00
Roman Khimov
b1b184f77f
Merge pull request #692 from nspcc-dev/persist-timer-fix
core: reschedule the next persist in a second from previous one
2020-02-26 10:34:40 +03:00
Roman Khimov
c258adb532 core: move spent coin management out of the inner storeBlock loop
prevHash == input.PrevHash, so make less DB accesses and more real work. Fix
some bugs along the way:
 * spentCoins structure may already be present in the DB when persisting TX,
   there is nothing wrong with that and we shouldn't overwrite it
 * it's only used for NEO and only to check for claim validity. Thus, when
   processing claim tx the corresponding spentCoins should always be present
   in the DB
2020-02-25 17:21:09 +03:00
Roman Khimov
36c6b6af14 core: put unspents get/put one loop above in storeBlock
Everywhere in this code prevHash == input.PrevHash, thus we can easily move
some common code out of the loop saving on DB accesses and
serialization/deserialization.
2020-02-24 18:53:10 +03:00
Roman Khimov
5c9681508b transaction: strip off a layer of redirection from ClaimTX.Claims
We don't need a pointer here and this change makes this field compatible with
Transaction.Inputs which is useful in many scenarios.
2020-02-24 18:22:27 +03:00
Roman Khimov
ed9e9e8590 storage: add locking into (*MemoryStore).Seek
It was missing there.
2020-02-24 17:51:50 +03:00
Roman Khimov
b49808b766 core: reschedule the next persist in a second from previous one
It makes little sense queueing up several persistence goroutines (or actually
even running them concurrently).
2020-02-24 17:17:25 +03:00
Roman Khimov
d5e6028c13 core: add validator public key into the list of hashes to verify
That should be done for Enrollment transactions.
2020-02-21 20:04:16 +03:00
Roman Khimov
a903147b60 keys: rename Signature to GetScriptHash, make it return Uint160
Signature itself wasn't used at all and its name is very misleading, Uint160
script hash is way more useful.
2020-02-19 12:19:03 +03:00
Roman Khimov
eb11e5fb11 core: implement basic policying support, fix #370
Implement mempool and consensus block creation policies, almost the same as
SimplePolicy plugin for C# node provides with two caveats:
 * HighPriorityTxType is not configured and hardcoded to ClaimType
 * BlockedAccounts are not supported

Other than that it allows us to run successfuly as testnet CN, previously our
proposals were rejected because we were proposing blocks with oversized
transactions (that are rejected by PoolTx() now).

Mainnet and testnet configuration files are updated accordingly, but privnet
is left as is with no limits.

Configuration is currently attached to the Blockchain and so is the code that
does policying, it may be moved somewhere in the future, but it works for
now.
2020-02-19 12:19:02 +03:00
Roman Khimov
22f5667530 mempool: return fee along with tx when requesting tx
Users of GetVerifiedTransactions() don't want to recalculate tx fee and it's
nice to have it returned from TryGetValue() also sometimes.
2020-02-19 12:19:02 +03:00