Fix unexpected messy missing diff

lib/assertions.js

@@ -1357,7 +1357,7 @@ module.exports = expect => {
   );
 
   expect.addAssertion(
-    '<any|Error|object> to [exhaustively] satisfy <expect.it>',
+    '<any|Error> to [exhaustively] satisfy <expect.it>',
     (expect, subject, value) => expect.promise(() => value(subject))
   );
 
@@ -1410,7 +1410,7 @@ module.exports = expect => {
   );
 
   expect.addAssertion(
-    '<any> to [exhaustively] satisfy [assertion] <expect.it>',
+    '<any|object> to [exhaustively] satisfy [assertion] <expect.it>',
     (expect, subject, value) =>
       expect.withError(
         () => value(subject, expect.context),

test/assertions/to-satisfy.spec.js

@@ -961,6 +961,67 @@ describe('to satisfy assertion', () => {
     });
   });
 
+  describe('with an expect.it and customised types', () => {
+    function Foo(thing) {
+      this.thing = thing;
+    }
+    const clonedExpect = expect.clone();
+
+    clonedExpect.addType({
+      name: 'Foo',
+      identify(obj) {
+        return obj instanceof Foo;
+      },
+      inspect(obj, depth, output) {
+        output.text('Foo', 'green');
+      }
+    });
+
+    clonedExpect.addAssertion(
+      '<Foo> to satisfy <object>',
+      (expect, subject, value) => {
+        return expect.withError(
+          () => expect(subject.thing, 'to satisfy', value.thing),
+          err => {
+            expect.fail({
+              diff: (output, diff, inspect, equal) => {
+                output.text('-- custom diff --', 'yellow').nl(2);
+
+                const thingDiff = err.getDiff(output);
+                if (thingDiff) {
+                  output.append(thingDiff);
+                }
+
+                return output;
+              }
+            });
+          }
+        );
+      }
+    );
+
+    it('should handle async diffs with nested parts', () =>
+      expect(
+        () =>
+          clonedExpect(new Foo({ foo: 123 }), 'to satisfy', {
+            thing: expect.it('when delayed a little bit', 'to equal', {
+              foo: 787
+            })
+          }),
+        'to error',
+        'expected Foo\n' +
+          "to satisfy { thing: expect.it('when delayed a little bit', 'to equal', { foo: 787 }) }\n" +
+          '\n' +
+          '-- custom diff --\n' +
+          '\n' +
+          'expected { foo: 123 } when delayed a little bit to equal { foo: 787 }\n' +
+          '\n' +
+          '{\n' +
+          '  foo: 123 // should equal 787\n' +
+          '}'
+      ));
+  });
+
   it('should support diffs in the error report', () => {
     expect(
       function() {