Neo Legacy Smart Contract Debugger launch.config Reference

Note, this document is for Neo Legacy smart contract launch configurations (i.e. .AVM files). For information about Neo N3 smart contract launch configurations, please see this document.

The Neo Smart Contract Debugger enables fine grained execution control via custom configuration settings in launch.json. This document provides information on these settings.

program

Absolute path to AVM file being debugged.

Examples:

"program": "${workspaceFolder}\\bin\\Debug\\netstandard2.0\\publish\\domain.avm",

JSON Schema:

"program": {
    "type": "string"
},

args

Command line arguments passed to the contract entrypoint. JSON strings that are prefixed with '0x' are treated as a hex-encoded byte array. JSON strings that are prefixed with '@' are treated a base-58 encoded address.

Examples:

"args": ["register", ["neo.org", "Harry Pierson"]],

// 0x prefixed strings are treated as hex-encoded byte arrays
"args": ["getTxInfo", ["0xd2cbfbe9bec47318113e4d41c95174023851df74d7cb2a9e4049d5c84d2b2a6d"]],

// '@' prefixed strings are treated as base-58 encoded Neo addresses
"args": ["balanceOf", ["@AXwFY3qdGm6sYn8p59E7ckKWsZwdJyrHdn"]],

JSON Schema:

"args": {
    "type": "array",
    "default": []
},

return-types

Specifies the expected return type of the contract entry-point. Particularly useful when the contract entry-point returns a C# object, but the specific operation being invoked returns a strongly-typed value.

Note, it is possible for Neo smart contracts to have multiple return values. Smart contracts compiled from C# always have a single return value, but the configuration property name is plural and the value must be an array.

Examples:

"return-types": ["bool"],

"return-types": ["string"],

JSON Schema:

"return-types": {
    "type": "array",
    "items": {
        "type": "string",
        "enum": [
            "int",
            "bool",
            "string",
            "hex",
            "byte[]"
        ]
    }
},

checkpoint

Path to a Neo-Express checkpoint to use for blockchain data.

Examples:

"checkpoint": "${workspaceFolder}\\checkpoints\\3-mint-tokens-invoked.neo-express-checkpoint",

JSON Schema:

"checkpoint": {
    "type": "string"
},

storage

Key/value pairs used to populate debugger's emulated storage. Similar to other launch configuration settings, strings prefixed with '0x' are treated as hex-encoded byte arrays.

If a specified key already exists in the checkpoint file, the value specified in the launch configuration takes precedence.

JSON for the storage configuration setting can be generated via the Neo-Express contract storage command by using the --json argument.

Examples:

"storage": [
    {
        "key": "neo.org",
        "value": "Neo Foundation"
    }
],

"storage": [
    {
        "key": "0x8a6f1e4f13022b26e56e957cb8251b082f0748b1007465737361",
        "value": "0x174876e800"
    },
    {
        "key": "0x796c707075536c61746f740074636172746e6f63",
        "value": "0x174876e800"
    },
    {
        "key": "0xd2cbfbe9bec47318113e4d41c95174023851df74d7cb2a9e4049d5c84d2b2a6d006f666e497874",
        "value": "0x174876e80005028a6f1e4f13022b26e56e957cb8251b082f0748b1140000000380"
    },
],

JSON Schema:

"storage": {
    "type": "array",
    "items": {
        "type": "object",
        "required": [
            "key",
            "value"
        ],
        "properties": {
            "key": {
                "type": "string"
            },
            "value": {
                "type": "string"
            },
            "constant": {
                "type": "boolean"
            }
        }
    },
    "default": []
},

sourceFileMap

Optional source file mappings passed to the debug engine

Example:

"sourceFileMap": {
    "C:\foo": "/home/user/foo"
}

JSON Schema:

"sourceFileMap": {
    "type": "object",
    "additionalProperties": {
        "type": "string"
    }
},

stored-contracts

Optional additional contracts to load for dynamic invoke scenarios. Stored contracts can include optional emulated storage key/value pairs as described above.

Example:

"stored-contracts": [
    "${workspaceFolder}/Second/bin/Debug/netstandard2.0/Second.avm",
    {
        "program": "${workspaceFolder}/Third/bin/Debug/netstandard2.0/Third.avm",
        "storage": [
            {
                "key": "neo.org",
                "value": "Neo Foundation"
            }
        ],
    }
],

JSON Schema:

"stored-contracts": {
    "type": "array",
    "description": "",
    "items": {
        "oneOf": [
            {
                "type": "string",
                "description": "Absolute path to AVM file"
            },
            {
                "type": "object",
                "required": [
                    "program"
                ],
                "properties": {
                    "program": {
                        "type": "string",
                    },
                    "storage": {
                        "type": "array",
                        "items": {
                            "type": "object",
                            "required": [
                                "key",
                                "value"
                            ],
                            "properties": {
                                "key": {
                                    "type": "string"
                                },
                                "value": {
                                    "type": "string"
                                },
                                "constant": {
                                    "type": "boolean"
                                }
                            }
                        }
                    }
                }
            }
        ]
    }
}

runtime

Specifies behavior of Runtime.Trigger and Runtime.CheckWitness members.

Runtime.Trigger returns either TriggerType.Verification or TriggerType.Application. By default, the debugger return TriggerType.Application for Runtime.Trigger, but this can be overridden by the runtime.trigger configuration property.

Runtime.CheckWitness takes a byte array and returns a boolean. The runtime.witnesses configuration property can either accept an array of hex-encoded byte arrays to compare the method parameter to or an object with a check-result property containing a hard-coded boolean value to return, regardless of the parameter passed to Runtime.CheckWitness.

Examples:

"runtime": {
    "witnesses": {
        "check-result": true
    }
}

JSON Schema:

"runtime": {
"type": "object",
"properties": {
"trigger": {
    "type": "string",
    "enum": [
        "verification",
        "application"
    ]
},
"witnesses": {
    "oneOf": [
        {
            "type": "array",
            "items": "string"
        },
        {
            "type": "object",
            "required": [
                "check-result"
            ],
            "properties": {
                "check-result": {
                    "type": "boolean"
                }
            }
        }
    ]
}

utxo

UTXO assets (aka NEO and GAS) to attach to the transaction being debugged. Objects in the input array are compatible with objects in the result.balance.unspent array of getunspents RPC endpoint. You can retrieve unspents information from Neo-Express via the show unspents command. The input.value property is permitted for compatibility with getunspents JSON response format but is not used by the debugger.

Examples:

"utxo": {
    "inputs": [
        {
            "txid": "0xf5e388f6a98a133755190f06e4dd3c9d9afd916a1e27b52250f1d54d405086cf",
            "n": 0
        }
    ],
    "outputs": [
        {
            "asset": "neo",
            "value": 1000,
            "address": "0x30f41a14ca6019038b055b585d002b287b5fdd47"
        }
    ]
},

JSON Schema:

"utxo": {
    "type": "object",
    "properties": {
        "inputs": {
            "type": "array",
            "required": [
                "txid",
                "n"
            ],
            "properties": {
                "txid": { "type": "string" },
                "n": { "type": "number" },
                "value": { "type": "number" }
            }
        },
        "outputs": {
            "type": "array",
            "required": [
                "asset",
                "value",
                "address"
            ],
            "properties": {
                "asset": { "type": "string" },
                "value": { "type": "number" },
                "address": { "type": "string" }
            }
        }
    }
},