fix(prefer-to-contain): check that expect argument is defined before use (#542)

* fix(prefer-to-contain): check that expect argument is defined before use

* chore: regenerate `yarn.lock`

Author: G-Rath

src/rules/__tests__/prefer-to-contain.test.ts

@@ -5,6 +5,7 @@ const ruleTester = new TSESLint.RuleTester();
 
 ruleTester.run('prefer-to-contain', rule, {
   valid: [
+    'expect().toBe(false);',
     'expect(a).toContain(b);',
     "expect(a.name).toBe('b');",
     'expect(a).toBe(true);',

src/rules/prefer-to-contain.ts

@@ -187,6 +187,7 @@ export default createRule({
 
         if (
           !matcher ||
+          !includesCall ||
           (modifier && modifier.name !== ModifierName.not) ||
           !isBooleanEqualityMatcher(matcher) ||
           !isFixableIncludesCallExpression(includesCall)