Add strictArgumentEncodingCheck to BaseContract and use it in contract templates

4 files changed, 183 insertions, 4 deletions

diff --git a/packages/utils/package.json b/packages/utils/package.json
index ee150cb0e..46c1d05d0 100644
--- a/packages/utils/package.json
+++ b/packages/utils/package.json
@@ -5,12 +5,13 @@
         "node": ">=6.12"
     },
     "description": "0x TS utils",
-    "main": "lib/index.js",
-    "types": "lib/index.d.ts",
+    "main": "lib/src/index.js",
+    "types": "lib/src/index.d.ts",
     "scripts": {
         "watch_without_deps": "tsc -w",
         "build": "tsc && copyfiles -u 2 './lib/monorepo_scripts/**/*' ./scripts",
         "clean": "shx rm -rf lib scripts",
+        "test": "mocha --require source-map-support/register --require make-promises-safe lib/test/**/*_test.js --bail --exit",
         "lint": "tslint --project .",
         "manual:postpublish": "yarn build; node ./scripts/postpublish.js"
     },
@@ -27,12 +28,15 @@
         "@0xproject/monorepo-scripts": "^1.0.4",
         "@0xproject/tslint-config": "^1.0.4",
         "@types/lodash": "4.14.104",
+        "@types/mocha": "^2.2.42",
         "copyfiles": "^1.2.0",
         "make-promises-safe": "^1.1.0",
         "npm-run-all": "^4.1.2",
         "shx": "^0.2.2",
         "tslint": "5.11.0",
-        "typescript": "2.9.2"
+        "typescript": "2.9.2",
+        "chai": "^4.0.1",
+        "mocha": "^4.0.1"
     },
     "dependencies": {
         "@0xproject/types": "^1.0.1-rc.3",
diff --git a/packages/utils/src/abi_utils.ts b/packages/utils/src/abi_utils.ts
index 421dd405c..16aa72afd 100644
--- a/packages/utils/src/abi_utils.ts
+++ b/packages/utils/src/abi_utils.ts
@@ -1,7 +1,160 @@
 import { AbiDefinition, AbiType, ContractAbi, DataItem, MethodAbi } from 'ethereum-types';
 import * as _ from 'lodash';
 
+import { BigNumber } from './configured_bignumber';
+
+export type EthersParamName = null | string | EthersNestedParamName;
+
+export interface EthersNestedParamName {
+    name: string | null;
+    names: EthersParamName[];
+}
+
+// Note(albrow): This function is unexported in ethers.js. Copying it here for
+// now.
+// Source: https://github.com/ethers-io/ethers.js/blob/884593ab76004a808bf8097e9753fb5f8dcc3067/contracts/interface.js#L30
+function parseEthersParams(params: DataItem[]): { names: EthersParamName[]; types: string[] } {
+    const names: EthersParamName[] = [];
+    const types: string[] = [];
+
+    params.forEach((param: DataItem) => {
+        if (param.components != null) {
+            let suffix = '';
+            const arrayBracket = param.type.indexOf('[');
+            if (arrayBracket >= 0) { suffix = param.type.substring(arrayBracket); }
+
+            const result = parseEthersParams(param.components);
+            names.push({ name: (param.name || null), names: result.names });
+            types.push('tuple(' + result.types.join(',') + ')' + suffix);
+        } else {
+            names.push(param.name || null);
+            types.push(param.type);
+        }
+    });
+
+    return {
+        names,
+        types,
+    };
+}
+
+// returns true if x is equal to y and false otherwise. Performs some minimal
+// type conversion and data massaging for x and y, depending on type. name and
+// type should typically be derived from parseEthersParams.
+function isAbiDataEqual(name: EthersParamName, type: string, x: any, y: any): boolean {
+    if (_.isUndefined(x) && _.isUndefined(y)) {
+        return true;
+    } else if (_.isUndefined(x) && !_.isUndefined(y)) {
+        return false;
+    } else if (!_.isUndefined(x) && _.isUndefined(y)) {
+        return false;
+    }
+    if (_.endsWith(type, '[]')) {
+        // For array types, we iterate through the elements and check each one
+        // individually. Strangely, name does not need to be changed in this
+        // case.
+        if (x.length !== y.length) {
+            return false;
+        }
+        const newType = _.trimEnd(type, '[]');
+        for (let i = 0; i < x.length; i++) {
+            if (!isAbiDataEqual(name, newType, x[i], y[i])) {
+                return false;
+            }
+        }
+        return true;
+    }
+    if (_.startsWith(type, 'tuple(')) {
+        if (_.isString(name)) {
+            throw new Error('Internal error: type was tuple but names was a string');
+        } else if (_.isNull(name)) {
+            throw new Error('Internal error: type was tuple but names was a null');
+        }
+        // For tuples, we iterate through the underlying values and check each
+        // one individually.
+        const types = splitTupleTypes(type);
+        if (types.length !== name.names.length) {
+            throw new Error(`Internal error: parameter types/names length mismatch (${types.length} != ${name.names.length})`);
+        }
+        for (let i = 0; i < types.length; i++) {
+            // For tuples, name is an object with a names property that is an
+            // array. As an example, for orders, name looks like:
+            //
+            //  {
+            //      name: 'orders',
+            //      names: [
+            //          'makerAddress',
+            //          // ...
+            //          'takerAssetData'
+            //      ]
+            //  }
+            //
+            const nestedName = _.isString(name.names[i]) ? name.names[i] as string : (name.names[i] as EthersNestedParamName).name as string;
+            if (!isAbiDataEqual(name.names[i], types[i], x[nestedName], y[nestedName])) {
+                return false;
+            }
+        }
+        return true;
+    } else if (type === 'address' || type === 'bytes') {
+        // HACK(albrow): ethers.js sometimes changes the case of addresses/bytes
+        // when decoding/encoding. To account for that, we convert to lowercase
+        // before comparing.
+        return _.isEqual(_.toLower(x), _.toLower(y));
+    } else if (_.startsWith(type, 'uint') || _.startsWith(type, 'int')) {
+        return new BigNumber(x).eq(new BigNumber(y));
+    }
+    return _.isEqual(x, y);
+}
+
+// splitTupleTypes splits a tuple type string (of the form `tuple(X)` where X is
+// any other type or list of types) into its component types. It works with
+// nested tuples, so, e.g., `tuple(tuple(uint256,address),bytes32)` will yield:
+// `['tuple(uint256,address)', 'bytes32']`. It expects exactly one tuple type as
+// an argument (not an array).
+function splitTupleTypes(type: string): string[] {
+    if (_.endsWith(type, '[]')) {
+        throw new Error('Internal error: array types are not supported');
+    } else if (!_.startsWith(type, 'tuple(')) {
+        throw new Error('Internal error: expected tuple type but got non-tuple type: ' + type);
+    }
+    // Trim the outtermost tuple().
+    const trimmedType = type.substring('tuple('.length, type.length - 1);
+    const types: string[] = [];
+    let currToken = '';
+    let parenCount = 0;
+    // Tokenize the type string while keeping track of parentheses.
+    for (const char of trimmedType) {
+        switch (char) {
+            case '(':
+                parenCount += 1;
+                currToken += char;
+                break;
+            case ')':
+                parenCount -= 1;
+                currToken += char;
+                break;
+            case ',':
+                if (parenCount === 0) {
+                    types.push(currToken);
+                    currToken = '';
+                    break;
+                } else {
+                    currToken += char;
+                    break;
+                }
+            default:
+                currToken += char;
+                break;
+        }
+    }
+    types.push(currToken);
+    return types;
+}
+
 export const abiUtils = {
+    parseEthersParams,
+    isAbiDataEqual,
+    splitTupleTypes,
     parseFunctionParam(param: DataItem): string {
         if (param.type === 'tuple') {
             // Parse out tuple types into {type_1, type_2, ..., type_N}
diff --git a/packages/utils/test/abi_utils_test.ts b/packages/utils/test/abi_utils_test.ts
new file mode 100644
index 000000000..0ebee64c4
--- /dev/null
+++ b/packages/utils/test/abi_utils_test.ts
@@ -0,0 +1,19 @@
+import * as chai from 'chai';
+import 'mocha';
+
+import { abiUtils } from '../src';
+
+const expect = chai.expect;
+
+describe('abiUtils', () => {
+    describe('splitTupleTypes', () => {
+        it('handles basic types', () => {
+            const got = abiUtils.splitTupleTypes('tuple(bytes,uint256,address)');
+            expect(got).to.deep.equal(['bytes', 'uint256', 'address']);
+        });
+        it('handles nested tuple types', () => {
+            const got = abiUtils.splitTupleTypes('tuple(tuple(bytes,uint256),address)');
+            expect(got).to.deep.equal(['tuple(bytes,uint256)', 'address']);
+        });
+    });
+});
diff --git a/packages/utils/tsconfig.json b/packages/utils/tsconfig.json
index c56d255d5..852708eba 100644
--- a/packages/utils/tsconfig.json
+++ b/packages/utils/tsconfig.json
@@ -3,5 +3,8 @@
     "compilerOptions": {
         "outDir": "lib"
     },
-    "include": ["./src/**/*"]
+    "include": [
+        "src/**/*",
+        "test/**/*"
+    ]
 }