fix: migrate null schedule to [] (#1021)

lib/config/massage.js

@@ -18,7 +18,7 @@ function massageConfig(config) {
     const val = config[key];
     if (allowedStrings.includes(key) && typeof val === 'string') {
       massagedConfig[key] = [val];
-    } else if (key === 'npmToken' && val.length < 30) {
+    } else if (key === 'npmToken' && val && val.length < 30) {
       massagedConfig.npmrc = `//registry.npmjs.org/:_authToken=${val}\n`;
       delete massagedConfig.npmToken;
     } else if (isObject(val)) {

lib/config/migration.js

@@ -99,6 +99,9 @@ function migrateConfig(config, parentConfig) {
       isMigrated = true;
       migratedConfig.packagePatterns = [val];
       delete migratedConfig.packagePattern;
+    } else if (key === 'schedule' && !val) {
+      isMigrated = true;
+      migratedConfig.schedule = [];
     } else if (key === 'schedule') {
       // massage to array first
       const schedules = typeof val === 'string' ? [val] : val;

test/config/__snapshots__/migration.spec.js.snap

@@ -18,12 +18,13 @@ Object {
     "minor": Object {
       "automerge": true,
     },
+    "schedule": Array [],
   },
   "enabled": true,
   "ignorePaths": Array [
     "node_modules/",
   ],
-  "lockFileConfig": Object {
+  "lockFileMaintenance": Object {
     "automerge": true,
     "schedule": "before 5am",
   },

test/config/migration.spec.js

@@ -36,12 +36,13 @@ describe('config/migration', () => {
             enabled: false,
           },
         ],
-        lockFileConfig: {
+        lockFileMaintenance: {
           automerge: 'any',
           schedule: 'before 5am every day',
         },
         devDependencies: {
           automerge: 'minor',
+          schedule: null,
         },
         depTypes: [
           'dependencies',