Update JSON validation logic

package.json

@@ -33,8 +33,7 @@
   "dependencies": {
     "@types/debug": "^4.1.7",
     "debug": "^4.3.4",
-    "fast-deep-equal": "^3.1.3",
-    "superstruct": "^0.16.5"
+    "superstruct": "^0.16.7"
   },
   "devDependencies": {
     "@lavamoat/allow-scripts": "^2.0.3",

src/__fixtures__/json.ts

@@ -1112,22 +1112,11 @@ export const COMPLEX_OBJECT = {
         t: [true, true, true],
         f: [false, false, false],
         nulls: [null, null, null],
-        undef: undefined,
-        mixed: [
-          null,
-          undefined,
-          null,
-          undefined,
-          null,
-          true,
-          null,
-          false,
-          null,
-          undefined,
-        ],
+        undef: null,
+        mixed: [null, null, null, null, null, true, null, false, null, null],
         inObject: {
           valueOne: null,
-          valueTwo: undefined,
+          valueTwo: null,
           t: true,
           f: false,
         },
@@ -1159,25 +1148,3 @@ export const ARRAY_OF_DIFFRENT_KINDS_OF_NUMBERS = [
   -5e-11, 5e-9, 0.000000000001, -0.00000000009, 100000.00000008, -100.88888,
   0.333, 1000000000000,
 ];
-
-export const ARRAY_OF_MIXED_SPECIAL_OBJECTS = [
-  null,
-  undefined,
-  null,
-  undefined,
-  undefined,
-  undefined,
-  null,
-  null,
-  null,
-  undefined,
-];
-
-export const OBJECT_MIXED_WITH_UNDEFINED_VALUES = {
-  a: undefined,
-  b: 'b',
-  c: undefined,
-  d: 'd',
-  e: undefined,
-  f: 'f',
-};

src/json.test.ts

@@ -1,7 +1,6 @@
 import * as superstructModule from 'superstruct';
 import {
   ARRAY_OF_DIFFRENT_KINDS_OF_NUMBERS,
-  ARRAY_OF_MIXED_SPECIAL_OBJECTS,
   COMPLEX_OBJECT,
   JSON_FIXTURES,
   JSON_RPC_ERROR_FIXTURES,
@@ -12,7 +11,6 @@ import {
   JSON_RPC_RESPONSE_FIXTURES,
   JSON_RPC_SUCCESS_FIXTURES,
   NON_SERIALIZABLE_NESTED_OBJECT,
-  OBJECT_MIXED_WITH_UNDEFINED_VALUES,
 } from './__fixtures__';
 import {
   assertIsJsonRpcFailure,
@@ -522,24 +520,15 @@ describe('json', () => {
       ]);
     });
 
-    it('should return true for serialization and 2 for a size when only one key with undefined value is provided', () => {
+    it('should return false for serialization and 0 for a size when only one key with undefined value is provided', () => {
       const valueToSerialize = {
         a: undefined,
       };
 
-      expect(validateJsonAndGetSize(valueToSerialize)).toStrictEqual([true, 2]);
-    });
-
-    it('should return true for serialization and 25 for a size when some of the values are undefined', () => {
-      expect(
-        validateJsonAndGetSize(OBJECT_MIXED_WITH_UNDEFINED_VALUES),
-      ).toStrictEqual([true, 25]);
-    });
-
-    it('should return true for serialization and 17 for a size with mixed null and undefined in an array', () => {
-      expect(
-        validateJsonAndGetSize(ARRAY_OF_MIXED_SPECIAL_OBJECTS),
-      ).toStrictEqual([true, 51]);
+      expect(validateJsonAndGetSize(valueToSerialize)).toStrictEqual([
+        false,
+        0,
+      ]);
     });
 
     it('should return true for serialization and 73 for a size, for an array of numbers', () => {
@@ -548,10 +537,10 @@ describe('json', () => {
       ).toStrictEqual([true, 73]);
     });
 
-    it('should return true for serialization and 1259 for a size of a complex nested object', () => {
+    it('should return true for serialization and 1288 for a size of a complex nested object', () => {
       expect(validateJsonAndGetSize(COMPLEX_OBJECT)).toStrictEqual([
         true,
-        1259,
+        1288,
       ]);
     });
 
@@ -611,6 +600,12 @@ describe('json', () => {
       ]);
     });
 
+    it('returns true for serialization and 37 for a size when checking an array', () => {
+      expect(
+        validateJsonAndGetSize(['foo', 'bar', null, ['foo', 'bar', null]]),
+      ).toStrictEqual([true, 37]);
+    });
+
     it('should return true or false for validity depending on the test scenario from ECMA TC39 (test262)', () => {
       // This test will perform a series of validation assertions.
       // These tests are taken from ECMA TC39 (test262) test scenarios used
@@ -761,7 +756,7 @@ describe('json', () => {
       expect(validateJsonAndGetSize(false, true)).toStrictEqual([true, 0]);
       expect(validateJsonAndGetSize('str', true)).toStrictEqual([true, 0]);
       expect(validateJsonAndGetSize(123, true)).toStrictEqual([true, 0]);
-      expect(validateJsonAndGetSize(undefined, true)).toStrictEqual([true, 0]);
+      expect(validateJsonAndGetSize(undefined, true)).toStrictEqual([false, 0]);
 
       // Value: string escape ASCII
       const charToJson = {

src/json.ts

@@ -1,19 +1,16 @@
-import deepEqual from 'fast-deep-equal';
 import {
   array,
   assert,
-  boolean,
+  define,
   Infer,
   integer,
   is,
-  lazy,
   literal,
   nullable,
   number,
   object,
   omit,
   optional,
-  record,
   string,
   Struct,
   union,
@@ -37,15 +34,10 @@ function isErrorWithMessage(error: unknown): error is { message: string } {
   return typeof error === 'object' && error !== null && 'message' in error;
 }
 
-// Note: This struct references itself, so TypeScript cannot infer the type.
-export const JsonStruct: Struct<Json> = union([
-  literal(null),
-  boolean(),
-  number(),
-  string(),
-  lazy(() => array(JsonStruct)),
-  lazy(() => record(string(), JsonStruct)),
-]);
+export const JsonStruct = define<Json>('Json', (value) => {
+  const [isValid] = validateJsonAndGetSize(value, true);
+  return isValid;
+});
 
 /**
  * Any JSON-compatible value.
@@ -65,11 +57,7 @@ export type Json =
  * @returns Whether the value is valid JSON.
  */
 export function isValidJson(value: unknown): value is Json {
-  try {
-    return deepEqual(value, JSON.parse(JSON.stringify(value)));
-  } catch (_) {
-    return false;
-  }
+  return is(value, JsonStruct);
 }
 
 /**
@@ -512,8 +500,7 @@ export function validateJsonAndGetSize(
     skipSizing: boolean,
   ): [isValid: boolean, plainTextSizeInBytes: number] {
     if (value === undefined) {
-      // Return zero for undefined, since these are omitted from JSON serialization
-      return [true, 0];
+      return [false, 0];
     } else if (value === null) {
       // Return already specified constant size for null (special object)
       return [true, skipSizing ? 0 : JsonSize.Null];
@@ -600,18 +587,6 @@ export function validateJsonAndGetSize(
               return 0;
             }
 
-            // If the size is 0, the value is undefined and undefined in an array
-            // when serialized will be replaced with null
-            if (size === 0 && Array.isArray(value)) {
-              size = JsonSize.Null;
-            }
-
-            // If the size is 0, that means the object is undefined and
-            // the rest of the object structure will be omitted
-            if (size === 0) {
-              return sum;
-            }
-
             // Objects will have be serialized with "key": value,
             // therefore we include the key in the calculation here
             const keySize = Array.isArray(value)

yarn.lock

@@ -871,14 +871,13 @@ __metadata:
     eslint-plugin-jsdoc: ^36.1.0
     eslint-plugin-node: ^11.1.0
     eslint-plugin-prettier: ^3.3.1
-    fast-deep-equal: ^3.1.3
     jest: ^28.1.0
     json-bigint: ^1.0.0
     prettier: ^2.2.1
     prettier-plugin-packagejson: ^2.2.11
     rimraf: ^3.0.2
     stdio-mock: ^1.2.0
-    superstruct: ^0.16.5
+    superstruct: ^0.16.7
     ts-jest: ^28.0.8
     tsd: ^0.24.1
     typedoc: ^0.23.10
@@ -5782,10 +5781,10 @@ __metadata:
   languageName: node
   linkType: hard
 
-"superstruct@npm:^0.16.5":
-  version: 0.16.5
-  resolution: "superstruct@npm:0.16.5"
-  checksum: 9f843c38695b584a605ae9b028629de18a85bd0dca0e9449b4ab98bb7b9ac3d82599870acbab9fbd2ee454c6b187af7e61562e252dfadabd974191ab4ab2e3ce
+"superstruct@npm:^0.16.7":
+  version: 0.16.7
+  resolution: "superstruct@npm:0.16.7"
+  checksum: c8c855ff6945da8a41048c6d236de7b1af5d4d9c31742b3ee54d65647c31597488620281f65e095d5efc9e2fbdaad529b8c8f2506c12569d428467c835a21477
   languageName: node
   linkType: hard