fix!: Charge gas for key length in gas meter (backport cosmos#10247) (c…

…osmos#10697)

* fix!: Charge gas for key length in gas meter (cosmos#10247)

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Closes: cosmos#10243

Charge the per-byte fee for the key length as for the values in gas meter

---

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- [ ] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
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- [ ] provided a link to the relevant issue or specification
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- [ ] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
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I have...

- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
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- [ ] reviewed state machine logic
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- [ ] manually tested (if applicable)

(cherry picked from commit dcf67d7)

* Move to state machine breaking

* revert deletion

* Fix test

Co-authored-by: likhita-809 <78951027+likhita-809@users.noreply.github.com>
Co-authored-by: marbar3778 <marbar3778@yahoo.com>
Co-authored-by: Amaury M <1293565+amaurym@users.noreply.github.com>

CHANGELOG.md

@@ -42,6 +42,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 ### State Machine Breaking
 
 * (store) [#10218](https://github.com/cosmos/cosmos-sdk/pull/10218) Charge gas even when there are no entries while seeking.
+* (store) [#10247](https://github.com/cosmos/cosmos-sdk/pull/10247) Charge gas for the key length in gas meter.
 
 ## [v0.44.5](https://github.com/cosmos/cosmos-sdk/releases/tag/v0.44.5) - 2021-12-02
 

store/gaskv/store.go

@@ -177,5 +177,6 @@ func (gi *gasIterator) consumeSeekGas() {
  gi.gasMeter.ConsumeGas(gi.gasConfig.ReadCostPerByte*types.Gas(len(key)), types.GasValuePerByteDesc)
  gi.gasMeter.ConsumeGas(gi.gasConfig.ReadCostPerByte*types.Gas(len(value)), types.GasValuePerByteDesc)
  }
+
  gi.gasMeter.ConsumeGas(gi.gasConfig.IterNextCostFlat, types.GasIterNextCostFlatDesc)
 }