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# AbiEvent Errors

:::info
`AbiEvent` is a re-export of ox's [`AbiEvent`](https://oxlib.sh/api/AbiEvent/errors). Refer to the ox documentation for the full reference.
:::

## `AbiEvent.AnonymousEventAmbiguityError`

Thrown when a log fits more than one anonymous event in an ABI. An anonymous log has no selector topic, so anonymous events with the same number of indexed inputs cannot be told apart.

### Examples

```ts twoslash
// @noErrors
import { Abi, AbiEvent } from 'viem/utils'

const abi = Abi.from([
  {
    anonymous: true,
    inputs: [
      { indexed: true, name: 'from', type: 'address' },
      { name: 'value', type: 'uint256' }
    ],
    name: 'Count',
    type: 'event'
  },
  {
    anonymous: true,
    inputs: [
      { indexed: true, name: 'from', type: 'address' },
      { name: 'note', type: 'string' }
    ],
    name: 'Message',
    type: 'event'
  }
])

AbiEvent.decodeLog(abi, {
  data: '0x0000000000000000000000000000000000000000000000000000000000000001',
  topics: [
    '0x000000000000000000000000a5cc3c03994db5b0d9a5eedd10cabab0813678ac'
  ]
})
// @error: AbiEvent.AnonymousEventAmbiguityError: Found ambiguous anonymous events for the log.
```

### Solution

Decode the log with the intended event.

```ts twoslash
// @noErrors
import { AbiEvent } from 'viem/utils'

const count = AbiEvent.from({
  anonymous: true,
  inputs: [
    { indexed: true, name: 'from', type: 'address' },
    { name: 'value', type: 'uint256' }
  ],
  name: 'Count',
  type: 'event'
})

AbiEvent.decode(count, {
  data: '0x0000000000000000000000000000000000000000000000000000000000000001',
  topics: [
    '0x000000000000000000000000a5cc3c03994db5b0d9a5eedd10cabab0813678ac'
  ]
})
```

## `AbiEvent.ArgsMismatchError`

Thrown when the provided arguments do not match the expected arguments.

### Examples

```ts twoslash
// @noErrors
import { AbiEvent } from 'viem/utils'

const abiEvent = AbiEvent.from(
  'event Transfer(address indexed from, address indexed to, uint256 value)'
)

const args = AbiEvent.decode(abiEvent, {
  data: '0x0000000000000000000000000000000000000000000000000000000000000001',
  topics: [
    '0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef',
    '0x000000000000000000000000a5cc3c03994db5b0d9a5eedd10cabab0813678ac',
    '0x000000000000000000000000a5cc3c03994db5b0d9a5eedd10cabab0813678ad'
  ]
})

AbiEvent.assertArgs(abiEvent, args, {
  from: '0xa5cc3c03994db5b0d9a5eedd10cabab0813678ad',
  to: '0xa5cc3c03994db5b0d9a5eedd10cabab0813678ac',
  value: 1n
})
// @error: AbiEvent.ArgsMismatchError: Given arguments do not match the expected arguments.
// @error: Event: event Transfer(address indexed from, address indexed to, uint256 value)
// @error: Expected Arguments:
// @error:   from:   0xa5cc3c03994db5b0d9a5eedd10cabab0813678ac
// @error:   to:     0xa5cc3c03994db5b0d9a5eedd10cabab0813678ad
// @error:   value:  1
// @error: Given Arguments:
// @error:   from:   0xa5cc3c03994db5b0d9a5eedd10cabab0813678ad
// @error:   to:     0xa5cc3c03994db5b0d9a5eedd10cabab0813678ac
// @error:   value:  1
```

### Solution

The provided arguments need to match the expected arguments.

```ts twoslash
// @noErrors
import { AbiEvent } from 'viem/utils'

const abiEvent = AbiEvent.from(
  'event Transfer(address indexed from, address indexed to, uint256 value)'
)

const args = AbiEvent.decode(abiEvent, {
  data: '0x0000000000000000000000000000000000000000000000000000000000000001',
  topics: [
    '0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef',
    '0x000000000000000000000000a5cc3c03994db5b0d9a5eedd10cabab0813678ac',
    '0x000000000000000000000000a5cc3c03994db5b0d9a5eedd10cabab0813678ad'
  ]
})

AbiEvent.assertArgs(abiEvent, args, {
  from: '0xa5cc3c03994db5b0d9a5eedd10cabab0813678ad', // [!code --]
  from: '0xa5cc3c03994db5b0d9a5eedd10cabab0813678ac', // [!code ++]
  to: '0xa5cc3c03994db5b0d9a5eedd10cabab0813678ac', // [!code --]
  to: '0xa5cc3c03994db5b0d9a5eedd10cabab0813678ad', // [!code ++]
  value: 1n
})
```

## `AbiEvent.DataMismatchError`

Thrown when the provided data size does not match the expected size from the non-indexed parameters.

### Examples

```ts twoslash
// @noErrors
import { AbiEvent } from 'viem/utils'

const abiEvent = AbiEvent.from(
  'event Transfer(address indexed from, address to, uint256 value)'
  //                                    ↑ 32 bytes + ↑ 32 bytes = 64 bytes
)

const args = AbiEvent.decode(abiEvent, {
  data: '0x0000000000000000000000000000000000000000000000000000000023c34600',
  //       ↑ 32 bytes ❌
  topics: [
    '0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef',
    '0x000000000000000000000000f39fd6e51aad88f6f4ce6ab8827279cfffb92266'
  ]
})
// @error: AbiEvent.DataMismatchError: Data size of 32 bytes is too small for non-indexed event parameters.
// @error: Non-indexed Parameters: (address to, uint256 value)
// @error: Data:   0x0000000000000000000000000000000000000000000000000000000023c34600 (32 bytes)
```

### Solution

Ensure that the data size matches the expected size.

```ts twoslash
// @noErrors
import { AbiEvent } from 'viem/utils'

const abiEvent = AbiEvent.from(
  'event Transfer(address indexed from, address to, uint256 value)'
  //                                    ↑ 32 bytes + ↑ 32 bytes = 64 bytes
)

const args = AbiEvent.decode(abiEvent, {
  data: '0x0x000000000000000000000000f39fd6e51aad88f6f4ce6ab8827279cfffb922660000000000000000000000000000000000000000000000000000000023c34600',
  //       ↑ 64 bytes ✅
  topics: [
    '0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef',
    '0x000000000000000000000000f39fd6e51aad88f6f4ce6ab8827279cfffb92266'
  ]
})
```

## `AbiEvent.FilterTypeNotSupportedError`

Thrown when the provided filter type is not supported.

### Examples

```ts twoslash
// @noErrors
import { AbiEvent } from 'viem/utils'

const transfer = AbiEvent.from(
  'event Transfer((string) indexed a, string b)'
)

AbiEvent.encode(transfer, {
  a: ['hello']
})
// @error: AbiEvent.FilterTypeNotSupportedError: Filter type "tuple" is not supported.
```

### Solution

Provide a valid event input type.

```ts twoslash
// @noErrors
import { AbiEvent } from 'viem/utils'

const transfer = AbiEvent.from(
  'event Transfer((string) indexed a, string b)'
) // [!code --]
const transfer = AbiEvent.from(
  'event Transfer(string indexed a, string b)'
) // [!code ++]
```

## `AbiEvent.InputNotFoundError`

Thrown when no argument was found on the event signature.

### Examples

```ts twoslash
// @noErrors
import { AbiEvent } from 'viem/utils'

const abiEvent = AbiEvent.from(
  'event Transfer(address indexed from, address indexed to, uint256 value)'
)

const args = AbiEvent.decode(abiEvent, {
  data: '0x0000000000000000000000000000000000000000000000000000000000000001',
  topics: [
    '0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef',
    '0x000000000000000000000000a5cc3c03994db5b0d9a5eedd10cabab0813678ac',
    '0x000000000000000000000000a5cc3c03994db5b0d9a5eedd10cabab0813678ad'
  ]
})

AbiEvent.assertArgs(abiEvent, args, {
  a: 'b',
  from: '0xa5cc3c03994db5b0d9a5eedd10cabab0813678ac',
  to: '0xa5cc3c03994db5b0d9a5eedd10cabab0813678ad',
  value: 1n
})
// @error: AbiEvent.InputNotFoundError: Parameter "a" not found on `event Transfer(address indexed from, address indexed to, uint256 value)`.
```

### Solution

Ensure the arguments match the event signature.

```ts twoslash
// @noErrors
import { AbiEvent } from 'viem/utils'

const abiEvent = AbiEvent.from(
  'event Transfer(address indexed from, address indexed to, uint256 value)'
)

const args = AbiEvent.decode(abiEvent, {
  data: '0x0000000000000000000000000000000000000000000000000000000000000001',
  topics: [
    '0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef',
    '0x000000000000000000000000a5cc3c03994db5b0d9a5eedd10cabab0813678ac',
    '0x000000000000000000000000a5cc3c03994db5b0d9a5eedd10cabab0813678ad'
  ]
})

AbiEvent.assertArgs(abiEvent, args, {
  a: 'b', // [!code --]
  from: '0xa5cc3c03994db5b0d9a5eedd10cabab0813678ac',
  to: '0xa5cc3c03994db5b0d9a5eedd10cabab0813678ad',
  value: 1n
})
```

## `AbiEvent.SelectorTopicMismatchError`

Thrown when the provided selector does not match the expected selector.

### Examples

```ts twoslash
// @noErrors
import { AbiEvent } from 'viem/utils'

const transfer = AbiEvent.from(
  'event Transfer(address indexed from, address indexed to, bool sender)'
)

AbiEvent.decode(transfer, {
  topics: [
    '0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef',
    '0x000000000000000000000000d8da6bf26964af9d7eed9e03e53415d37aa96045',
    '0x000000000000000000000000f39fd6e51aad88f6f4ce6ab8827279cfffb92266'
  ]
})
// @error: AbiEvent.SelectorTopicMismatchError: topics[0]="0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef" does not match the expected topics[0]="0x3da3cd3cf420c78f8981e7afeefa0eab1f0de0eb56e78ad9ba918ed01c0b402f".
// @error: Event: event Transfer(address indexed from, address indexed to, bool sender)
// @error: Selector: 0x3da3cd3cf420c78f8981e7afeefa0eab1f0de0eb56e78ad9ba918ed01c0b402f
```

### Solution

Ensure that the provided selector matches the selector of the event signature.

```ts twoslash
// @noErrors
import { AbiEvent } from 'viem/utils'

const transfer = AbiEvent.from(
  'event Transfer(address indexed from, address indexed to, bool sender)'
)

AbiEvent.decode(transfer, {
  topics: [
    '0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef', // [!code --]
    '0x3da3cd3cf420c78f8981e7afeefa0eab1f0de0eb56e78ad9ba918ed01c0b402f', // [!code ++]
    '0x000000000000000000000000d8da6bf26964af9d7eed9e03e53415d37aa96045',
    '0x000000000000000000000000f39fd6e51aad88f6f4ce6ab8827279cfffb92266'
  ]
})
```

## `AbiEvent.SelectorTopicNotFoundError`

Thrown when the selector topic is not found.

### Examples

```ts twoslash
// @noErrors
import { Abi, AbiEvent } from 'viem/utils'

const abi = Abi.from([
  'event Transfer(address indexed from)'
])

AbiEvent.decodeLog(abi, { topics: [], data: '0x' })
// @error: AbiEvent.SelectorTopicNotFoundError: Selector topic not found.
```

## `AbiEvent.TopicsMismatchError`

Thrown when the provided topics do not match the expected number of topics.

### Examples

```ts twoslash
// @noErrors
import { AbiEvent } from 'viem/utils'

const abiEvent = AbiEvent.from(
  'event Transfer(address indexed from, address indexed to, uint256 value)'
)

const args = AbiEvent.decode(abiEvent, {
  data: '0x0000000000000000000000000000000000000000000000000000000000000001',
  topics: [
    '0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef',
    '0x000000000000000000000000a5cc3c03994db5b0d9a5eedd10cabab0813678ac'
  ]
})
// @error: AbiEvent.TopicsMismatchError: Expected a topic for indexed event parameter "to" for "event Transfer(address indexed from, address indexed to, uint256 value)".
```

### Solution

Ensure that the topics match the expected number of topics.

```ts twoslash
// @noErrors
import { AbiEvent } from 'viem/utils'

const abiEvent = AbiEvent.from(
  'event Transfer(address indexed from, address indexed to, uint256 value)'
)

const args = AbiEvent.decode(abiEvent, {
  data: '0x0000000000000000000000000000000000000000000000000000000000000001',
  topics: [
    '0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef',
    '0x000000000000000000000000a5cc3c03994db5b0d9a5eedd10cabab0813678ac',
    '0x000000000000000000000000f39fd6e51aad88f6f4ce6ab8827279cfffb92266' // [!code ++]
  ]
})
```