test: initial stab at trying Ava test framework

package.json

@@ -42,6 +42,7 @@
     "packages/notifier"
   ],
   "devDependencies": {
+    "ava": "^3.11.1",
     "eslint": "^6.8.0",
     "eslint-config-airbnb": "^18.0.1",
     "eslint-config-airbnb-base": "^14.0.0",
@@ -70,5 +71,24 @@
   },
   "dependencies": {
     "@agoric/store": "^0.2.0"
+  },
+  "ava": {
+    "files": [
+      "packages/**/test/**/test-*"
+    ],
+    "concurrency": 12,
+    "failFast": false,
+    "failWithoutAssertions": true,
+    "environmentVariables": {
+      "MY_ENVIRONMENT_VARIABLE": "some value"
+    },
+    "verbose": false,
+    "require": [
+      "esm"
+    ],
+    "nodeArguments": [
+      "--trace-deprecation",
+      "--napi-modules"
+    ]
   }
 }

packages/ERTP/src/amountMath.js

@@ -77,7 +77,7 @@ function makeAmountMath(brand, mathHelpersName) {
 
     /**
      * Make an amount from a value by adding the brand.
-     * @param {any} allegedValue
+     * @param {Value} allegedValue
      * @returns {Amount}
      */
     make: allegedValue => {
@@ -89,7 +89,7 @@ function makeAmountMath(brand, mathHelpersName) {
 
     /**
      * Make sure this amount is valid and return it if so, throwing if invalid.
-     * @param {any} allegedAmount
+     * @param {Amount} allegedAmount
      * @returns {Amount} or throws if invalid
      */
     coerce: allegedAmount => {