Filter $$ref from examples (#4392)

* fix(dev-server): don't open localhost in a browser
* tests: refactor model-example enzyme tests to be more isolated
* tests: add failing sampleFromSchema tests for $$ref keys
* tests: add additional test for user-created $$ref values
* fix: create deeplyStripKey; use it to filter $$refs out of examples
* tests: add cases for deeplyStripKey

test/core/utils.js

@@ -21,7 +21,8 @@ import {
   createDeepLinkPath,
   escapeDeepLinkPath,
   sanitizeUrl,
-  extractFileNameFromContentDispositionHeader
+  extractFileNameFromContentDispositionHeader,
+  deeplyStripKey
 } from "core/utils"
 import win from "core/window"
 
@@ -942,6 +943,58 @@ describe("utils", function() {
     })
   })
 
+  describe("deeplyStripKey", function() {
+    it("should filter out a specified key", function() {
+      const input = {
+        $$ref: "#/this/is/my/ref",
+        a: {
+          $$ref: "#/this/is/my/other/ref",
+          value: 12345
+        }
+      }
+      const result = deeplyStripKey(input, "$$ref")
+      expect(result).toEqual({
+        a: {
+          value: 12345
+        }
+      })
+    })
+
+    it("should filter out a specified key by predicate", function() {
+      const input = {
+        $$ref: "#/this/is/my/ref",
+        a: {
+          $$ref: "#/keep/this/one",
+          value: 12345
+        }
+      }
+      const result = deeplyStripKey(input, "$$ref", (v) => v !== "#/keep/this/one")
+      expect(result).toEqual({
+        a: {
+          value: 12345,
+          $$ref: "#/keep/this/one"
+        }
+      })
+    })
+
+    it("should only call the predicate when the key matches", function() {
+      const input = {
+        $$ref: "#/this/is/my/ref",
+        a: {
+          $$ref: "#/this/is/my/other/ref",
+          value: 12345
+        }
+      }
+      let count = 0
+
+      const result = deeplyStripKey(input, "$$ref", () => {
+        count++
+        return true
+      })
+      expect(count).toEqual(2)
+    })
+  })
+
   describe("parse and serialize search", function() {
     afterEach(function() {
       win.location.search = ""