Add type checks for asymmetric matchers (#5069)

* Add type checks for asymmetric matchers * Expect other to only be a string
jestjs · Jan 7, 2018 · b86d932 · b86d932
1 parent a9a3df0
commit b86d932
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Showing 2 changed files with 11 additions and 0 deletions.
diff --git a/packages/expect/src/__tests__/asymmetric_matchers.test.js b/packages/expect/src/__tests__/asymmetric_matchers.test.js
@@ -142,6 +142,7 @@ test('ObjectContaining throws for non-objects', () => {
 test('StringContaining matches string against string', () => {
   jestExpect(stringContaining('en*').asymmetricMatch('queen*')).toBe(true);
   jestExpect(stringContaining('en').asymmetricMatch('queue')).toBe(false);
+  jestExpect(stringContaining('en').asymmetricMatch({})).toBe(false);
 });
 
 test('StringContaining throws for non-strings', () => {
@@ -153,11 +154,13 @@ test('StringContaining throws for non-strings', () => {
 test('StringMatching matches string against regexp', () => {
   jestExpect(stringMatching(/en/).asymmetricMatch('queen')).toBe(true);
   jestExpect(stringMatching(/en/).asymmetricMatch('queue')).toBe(false);
+  jestExpect(stringMatching(/en/).asymmetricMatch({})).toBe(false);
 });
 
 test('StringMatching matches string against string', () => {
   jestExpect(stringMatching('en').asymmetricMatch('queen')).toBe(true);
   jestExpect(stringMatching('en').asymmetricMatch('queue')).toBe(false);
+  jestExpect(stringMatching('en').asymmetricMatch({})).toBe(false);
 });
 
 test('StringMatching throws for non-strings and non-regexps', () => {

diff --git a/packages/expect/src/asymmetric_matchers.js b/packages/expect/src/asymmetric_matchers.js
@@ -193,6 +193,10 @@ class StringContaining extends AsymmetricMatcher {
   }
 
   asymmetricMatch(other: string) {
+    if (!isA('String', other)) {
+      return false;
+    }
+
     return other.includes(this.sample);
   }
 
@@ -218,6 +222,10 @@ class StringMatching extends AsymmetricMatcher {
   }
 
   asymmetricMatch(other: string) {
+    if (!isA('String', other)) {
+      return false;
+    }
+
     return this.sample.test(other);
   }