Merge pull request #1242 from voliva/contains-oneOf

(feat): expect value to contain oneOf

lib/chai/core/assertions.js

@@ -3118,6 +3118,14 @@ module.exports = function (chai, _) {
    *     expect(1).to.equal(1); // Recommended
    *     expect(1).to.not.be.oneOf([2, 3, 4]); // Not recommended
    *
+   * It can also be chained with `.contain` or `.include`, which will work with
+   * both arrays and strings:
+   * 
+   *     expect('Today is sunny').to.contain.oneOf(['sunny', 'cloudy'])
+   *     expect('Today is rainy').to.not.contain.oneOf(['sunny', 'cloudy'])
+   *     expect([1,2,3]).to.contain.oneOf([3,4,5])
+   *     expect([1,2,3]).to.not.contain.oneOf([4,5,6])
+   * 
    * `.oneOf` accepts an optional `msg` argument which is a custom error message
    * to show when the assertion fails. The message can also be given as the
    * second argument to `expect`.
@@ -3136,16 +3144,27 @@ module.exports = function (chai, _) {
     if (msg) flag(this, 'message', msg);
     var expected = flag(this, 'object')
       , flagMsg = flag(this, 'message')
-      , ssfi = flag(this, 'ssfi');
+      , ssfi = flag(this, 'ssfi')
+      , contains = flag(this, 'contains');
     new Assertion(list, flagMsg, ssfi, true).to.be.an('array');
 
-    this.assert(
+    if (contains) {
+      this.assert(
+        list.some(possibility => expected.indexOf(possibility) > -1)
+        , 'expected #{this} to contain one of #{exp}'
+        , 'expected #{this} to not contain one of #{exp}'
+        , list
+        , expected
+      );
+    } else {
+      this.assert(
         list.indexOf(expected) > -1
-      , 'expected #{this} to be one of #{exp}'
-      , 'expected #{this} to not be one of #{exp}'
-      , list
-      , expected
-    );
+        , 'expected #{this} to be one of #{exp}'
+        , 'expected #{this} to not be one of #{exp}'
+        , list
+        , expected
+      );
+    }
   }
 
   Assertion.addMethod('oneOf', oneOf);

test/expect.js

@@ -3282,6 +3282,12 @@ describe('expect', function () {
     var threeFour = [3, [4]];
     expect(threeFour).to.be.oneOf([1, 2, threeFour]);
 
+    expect([1, 2]).to.contain.oneOf([4,2,5]);
+    expect([3, 4]).to.not.contain.oneOf([2,1,5]);
+
+    expect('The quick brown fox jumps over the lazy dog').to.contain.oneOf(['cat', 'dog', 'bird']);
+    expect('The quick brown fox jumps over the lazy dog').to.not.contain.oneOf(['elephant', 'pigeon', 'lynx']);
+
     err(function () {
       expect(1).to.be.oneOf([2, 3], 'blah');
     }, "blah: expected 1 to be one of [ 2, 3 ]");