From 44c8bfabce4ba61488cfdea98f23b4e610f52ebe Mon Sep 17 00:00:00 2001
From: Carlo Palinckx <carlo@mijnwebwinkel.nl>
Date: Sun, 19 Aug 2018 21:12:54 +0200
Subject: [PATCH 1/6] added test to readQuery

---
 .../src/__tests__/cache.ts                    | 35 +++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/packages/apollo-cache-inmemory/src/__tests__/cache.ts b/packages/apollo-cache-inmemory/src/__tests__/cache.ts
index 8d4f7fe802a..3f54b2246f8 100644
--- a/packages/apollo-cache-inmemory/src/__tests__/cache.ts
+++ b/packages/apollo-cache-inmemory/src/__tests__/cache.ts
@@ -200,6 +200,7 @@ describe('Cache', () => {
         ),
       ).toEqual({ a: 1, b: 2 });
     });
+
     it('will read some data from the store with null variables', () => {
       const proxy = createCache({
         initialState: {
@@ -229,6 +230,40 @@ describe('Cache', () => {
         ),
       ).toEqual({ a: 1 });
     });
+
+    it('should not mutate arguments passed in', () => {
+      const proxy = createCache({
+        initialState: {
+          apollo: {
+            data: {
+              ROOT_QUERY: {
+                'field({"literal":true,"value":42})': 1,
+                'field({"literal":false,"value":42})': 2,
+              },
+            },
+          },
+        },
+      });
+
+      const args = {
+        query: gql`
+          query($literal: Boolean, $value: Int) {
+            a: field(literal: true, value: 42)
+            b: field(literal: $literal, value: $value)
+          }
+        `,
+        variables: {
+          literal: false,
+          value: 42,
+        },
+      };
+
+      const preQueryCopy = { ...args };
+
+      expect(stripSymbols(proxy.readQuery(args))).toEqual({ a: 1, b: 2 });
+
+      expect(preQueryCopy).toEqual(args);
+    });
   });
 
   describe('readFragment', () => {

From e2922c2a0e5993b8e54604ba2bf5502ec1ac2271 Mon Sep 17 00:00:00 2001
From: Carlo Palinckx <carlo@mijnwebwinkel.nl>
Date: Mon, 8 Oct 2018 17:15:18 +0200
Subject: [PATCH 2/6] deepcloned pre query copy

---
 packages/apollo-cache-inmemory/src/__tests__/cache.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/packages/apollo-cache-inmemory/src/__tests__/cache.ts b/packages/apollo-cache-inmemory/src/__tests__/cache.ts
index 3f54b2246f8..41b20a6a662 100644
--- a/packages/apollo-cache-inmemory/src/__tests__/cache.ts
+++ b/packages/apollo-cache-inmemory/src/__tests__/cache.ts
@@ -1,6 +1,7 @@
 import { ApolloCache } from 'apollo-cache';
 import gql, { disableFragmentWarnings } from 'graphql-tag';
 import { stripSymbols } from 'apollo-utilities';
+import _ from 'lodash';
 
 import { InMemoryCache, ApolloReducerConfig, NormalizedCache } from '..';
 
@@ -258,7 +259,7 @@ describe('Cache', () => {
         },
       };
 
-      const preQueryCopy = { ...args };
+      const preQueryCopy = _.cloneDeep(args);
 
       expect(stripSymbols(proxy.readQuery(args))).toEqual({ a: 1, b: 2 });
 

From f562d10622225005a5e8a46521dc93f9e6db4697 Mon Sep 17 00:00:00 2001
From: Hugh Willson <hugh@octonary.com>
Date: Sat, 27 Oct 2018 07:06:47 -0400
Subject: [PATCH 3/6] Slight code adjustments

---
 .../apollo-cache-inmemory/src/__tests__/cache.ts     | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/packages/apollo-cache-inmemory/src/__tests__/cache.ts b/packages/apollo-cache-inmemory/src/__tests__/cache.ts
index 41b20a6a662..12f3dc3f925 100644
--- a/packages/apollo-cache-inmemory/src/__tests__/cache.ts
+++ b/packages/apollo-cache-inmemory/src/__tests__/cache.ts
@@ -1,7 +1,7 @@
 import { ApolloCache } from 'apollo-cache';
 import gql, { disableFragmentWarnings } from 'graphql-tag';
 import { stripSymbols } from 'apollo-utilities';
-import _ from 'lodash';
+import { cloneDeep } from 'lodash';
 
 import { InMemoryCache, ApolloReducerConfig, NormalizedCache } from '..';
 
@@ -246,7 +246,7 @@ describe('Cache', () => {
         },
       });
 
-      const args = {
+      const options = {
         query: gql`
           query($literal: Boolean, $value: Int) {
             a: field(literal: true, value: 42)
@@ -259,11 +259,9 @@ describe('Cache', () => {
         },
       };
 
-      const preQueryCopy = _.cloneDeep(args);
-
-      expect(stripSymbols(proxy.readQuery(args))).toEqual({ a: 1, b: 2 });
-
-      expect(preQueryCopy).toEqual(args);
+      const preQueryCopy = cloneDeep(options);
+      expect(stripSymbols(proxy.readQuery(options))).toEqual({ a: 1, b: 2 });
+      expect(preQueryCopy).toEqual(options);
     });
   });
 

From 1bac2420fd10b053de9545ba2dc5a3680e1ade71 Mon Sep 17 00:00:00 2001
From: Hugh Willson <hugh@octonary.com>
Date: Sat, 27 Oct 2018 07:07:16 -0400
Subject: [PATCH 4/6] Convert CRLF's to LF's

---
 packages/apollo-cache/src/__tests__/cache.ts | 298 +++++++++----------
 1 file changed, 149 insertions(+), 149 deletions(-)

diff --git a/packages/apollo-cache/src/__tests__/cache.ts b/packages/apollo-cache/src/__tests__/cache.ts
index 34ecbaeb1c8..6f10d7c57d8 100644
--- a/packages/apollo-cache/src/__tests__/cache.ts
+++ b/packages/apollo-cache/src/__tests__/cache.ts
@@ -1,149 +1,149 @@
-import gql from 'graphql-tag';
-
-import { ApolloCache as Cache } from '../cache';
-
-class TestCache extends Cache {}
-
-describe('abstract cache', () => {
-  describe('transformDocument', () => {
-    it('returns the document', () => {
-      const test = new TestCache();
-      expect(test.transformDocument('a')).toBe('a');
-    });
-  });
-
-  describe('transformForLink', () => {
-    it('returns the document', () => {
-      const test = new TestCache();
-      expect(test.transformForLink('a')).toBe('a');
-    });
-  });
-
-  describe('readQuery', () => {
-    it('runs the read method', () => {
-      const test = new TestCache();
-      test.read = jest.fn();
-
-      test.readQuery({});
-      expect(test.read).toBeCalled();
-    });
-
-    it('defaults optimistic to false', () => {
-      const test = new TestCache();
-      test.read = ({ optimistic }) => optimistic;
-
-      expect(test.readQuery({})).toBe(false);
-      expect(test.readQuery({}, true)).toBe(true);
-    });
-  });
-
-  describe('readFragment', () => {
-    it('runs the read method', () => {
-      const test = new TestCache();
-      test.read = jest.fn();
-      const fragment = {
-        id: 'frag',
-        fragment: gql`
-          fragment a on b {
-            name
-          }
-        `,
-      };
-
-      test.readFragment(fragment);
-      expect(test.read).toBeCalled();
-    });
-
-    it('defaults optimistic to false', () => {
-      const test = new TestCache();
-      test.read = ({ optimistic }) => optimistic;
-      const fragment = {
-        id: 'frag',
-        fragment: gql`
-          fragment a on b {
-            name
-          }
-        `,
-      };
-
-      expect(test.readFragment(fragment)).toBe(false);
-      expect(test.readFragment(fragment, true)).toBe(true);
-    });
-  });
-
-  describe('writeQuery', () => {
-    it('runs the write method', () => {
-      const test = new TestCache();
-      test.write = jest.fn();
-
-      test.writeQuery({});
-      expect(test.write).toBeCalled();
-    });
-  });
-
-  describe('writeFragment', () => {
-    it('runs the write method', () => {
-      const test = new TestCache();
-      test.write = jest.fn();
-      const fragment = {
-        id: 'frag',
-        fragment: gql`
-          fragment a on b {
-            name
-          }
-        `,
-      };
-
-      test.writeFragment(fragment);
-      expect(test.write).toBeCalled();
-    });
-  });
-
-  describe('writeData', () => {
-    it('either writes a fragment or a query', () => {
-      const test = new TestCache();
-      test.read = jest.fn();
-      test.writeFragment = jest.fn();
-      test.writeQuery = jest.fn();
-
-      test.writeData({});
-      expect(test.writeQuery).toBeCalled();
-
-      test.writeData({ id: 1 });
-      expect(test.read).toBeCalled();
-      expect(test.writeFragment).toBeCalled();
-
-      // Edge case for falsey id
-      test.writeData({ id: 0 });
-      expect(test.read).toHaveBeenCalledTimes(2);
-      expect(test.writeFragment).toHaveBeenCalledTimes(2);
-    });
-
-    it('suppresses read errors', () => {
-      const test = new TestCache();
-      test.read = () => {
-        throw new Error();
-      };
-      test.writeFragment = jest.fn();
-
-      expect(() => test.writeData({ id: 1 })).not.toThrow();
-      expect(test.writeFragment).toBeCalled();
-    });
-
-    it('reads __typename from typenameResult or defaults to __ClientData', () => {
-      const test = new TestCache();
-      test.read = () => ({ __typename: 'a' });
-      let res;
-      test.writeFragment = obj =>
-        (res = obj.fragment.definitions[0].typeCondition.name.value);
-
-      test.writeData({ id: 1 });
-      expect(res).toBe('a');
-
-      test.read = () => ({});
-
-      test.writeData({ id: 1 });
-      expect(res).toBe('__ClientData');
-    });
-  });
-});
+import gql from 'graphql-tag';
+
+import { ApolloCache as Cache } from '../cache';
+
+class TestCache extends Cache {}
+
+describe('abstract cache', () => {
+  describe('transformDocument', () => {
+    it('returns the document', () => {
+      const test = new TestCache();
+      expect(test.transformDocument('a')).toBe('a');
+    });
+  });
+
+  describe('transformForLink', () => {
+    it('returns the document', () => {
+      const test = new TestCache();
+      expect(test.transformForLink('a')).toBe('a');
+    });
+  });
+
+  describe('readQuery', () => {
+    it('runs the read method', () => {
+      const test = new TestCache();
+      test.read = jest.fn();
+
+      test.readQuery({});
+      expect(test.read).toBeCalled();
+    });
+
+    it('defaults optimistic to false', () => {
+      const test = new TestCache();
+      test.read = ({ optimistic }) => optimistic;
+
+      expect(test.readQuery({})).toBe(false);
+      expect(test.readQuery({}, true)).toBe(true);
+    });
+  });
+
+  describe('readFragment', () => {
+    it('runs the read method', () => {
+      const test = new TestCache();
+      test.read = jest.fn();
+      const fragment = {
+        id: 'frag',
+        fragment: gql`
+          fragment a on b {
+            name
+          }
+        `,
+      };
+
+      test.readFragment(fragment);
+      expect(test.read).toBeCalled();
+    });
+
+    it('defaults optimistic to false', () => {
+      const test = new TestCache();
+      test.read = ({ optimistic }) => optimistic;
+      const fragment = {
+        id: 'frag',
+        fragment: gql`
+          fragment a on b {
+            name
+          }
+        `,
+      };
+
+      expect(test.readFragment(fragment)).toBe(false);
+      expect(test.readFragment(fragment, true)).toBe(true);
+    });
+  });
+
+  describe('writeQuery', () => {
+    it('runs the write method', () => {
+      const test = new TestCache();
+      test.write = jest.fn();
+
+      test.writeQuery({});
+      expect(test.write).toBeCalled();
+    });
+  });
+
+  describe('writeFragment', () => {
+    it('runs the write method', () => {
+      const test = new TestCache();
+      test.write = jest.fn();
+      const fragment = {
+        id: 'frag',
+        fragment: gql`
+          fragment a on b {
+            name
+          }
+        `,
+      };
+
+      test.writeFragment(fragment);
+      expect(test.write).toBeCalled();
+    });
+  });
+
+  describe('writeData', () => {
+    it('either writes a fragment or a query', () => {
+      const test = new TestCache();
+      test.read = jest.fn();
+      test.writeFragment = jest.fn();
+      test.writeQuery = jest.fn();
+
+      test.writeData({});
+      expect(test.writeQuery).toBeCalled();
+
+      test.writeData({ id: 1 });
+      expect(test.read).toBeCalled();
+      expect(test.writeFragment).toBeCalled();
+
+      // Edge case for falsey id
+      test.writeData({ id: 0 });
+      expect(test.read).toHaveBeenCalledTimes(2);
+      expect(test.writeFragment).toHaveBeenCalledTimes(2);
+    });
+
+    it('suppresses read errors', () => {
+      const test = new TestCache();
+      test.read = () => {
+        throw new Error();
+      };
+      test.writeFragment = jest.fn();
+
+      expect(() => test.writeData({ id: 1 })).not.toThrow();
+      expect(test.writeFragment).toBeCalled();
+    });
+
+    it('reads __typename from typenameResult or defaults to __ClientData', () => {
+      const test = new TestCache();
+      test.read = () => ({ __typename: 'a' });
+      let res;
+      test.writeFragment = obj =>
+        (res = obj.fragment.definitions[0].typeCondition.name.value);
+
+      test.writeData({ id: 1 });
+      expect(res).toBe('a');
+
+      test.read = () => ({});
+
+      test.writeData({ id: 1 });
+      expect(res).toBe('__ClientData');
+    });
+  });
+});

From cdf9f350d4bb281da4315bb7d7b044281244d83d Mon Sep 17 00:00:00 2001
From: Hugh Willson <hugh@octonary.com>
Date: Sat, 27 Oct 2018 07:09:10 -0400
Subject: [PATCH 5/6] Changelog update

---
 CHANGELOG.md | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 88413a3853d..a88e8642e23 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,11 @@
 - Optimistic tests cleanup. <br/>
   [@joshribakoff](https://github.com/joshribakoff) in [#3834](https://github.com/apollographql/apollo-client/pull/3834)
 
+### Apollo Cache (vNext)
+
+- Add `readQuery` test to make sure options aren't mutated.  <br/>
+  [@CarloPalinckx](https://github.com/CarloPalinckx) in [#3838](https://github.com/apollographql/apollo-client/pull/3838)
+
 ## Apollo Client (2.4.4)
 
 ### Apollo Utilities (1.0.24)

From 7bf18209298a92fb965acfc7bf6d4fc6e5cafdce Mon Sep 17 00:00:00 2001
From: Hugh Willson <hugh@octonary.com>
Date: Sat, 27 Oct 2018 07:17:53 -0400
Subject: [PATCH 6/6] Convert CRLF's to LF's

---
 .../src/__tests__/cache.ts                    | 2358 ++++++++---------
 1 file changed, 1179 insertions(+), 1179 deletions(-)

diff --git a/packages/apollo-cache-inmemory/src/__tests__/cache.ts b/packages/apollo-cache-inmemory/src/__tests__/cache.ts
index 12f3dc3f925..0cd4f2cc631 100644
--- a/packages/apollo-cache-inmemory/src/__tests__/cache.ts
+++ b/packages/apollo-cache-inmemory/src/__tests__/cache.ts
@@ -1,1179 +1,1179 @@
-import { ApolloCache } from 'apollo-cache';
-import gql, { disableFragmentWarnings } from 'graphql-tag';
-import { stripSymbols } from 'apollo-utilities';
-import { cloneDeep } from 'lodash';
-
-import { InMemoryCache, ApolloReducerConfig, NormalizedCache } from '..';
-
-disableFragmentWarnings();
-
-describe('Cache', () => {
-  function createCache({
-    initialState,
-    config,
-  }: {
-    initialState?: any;
-    config?: ApolloReducerConfig;
-  } = {}): ApolloCache<NormalizedCache> {
-    return new InMemoryCache(
-      config || { addTypename: false },
-      // XXX this is the old format. The tests need to be updated but since it is mapped down
-    ).restore(initialState ? initialState.apollo.data : {});
-  }
-
-  describe('readQuery', () => {
-    it('will read some data from the store', () => {
-      const proxy = createCache({
-        initialState: {
-          apollo: {
-            data: {
-              ROOT_QUERY: {
-                a: 1,
-                b: 2,
-                c: 3,
-              },
-            },
-          },
-        },
-      });
-      expect(
-        stripSymbols(
-          proxy.readQuery({
-            query: gql`
-              {
-                a
-              }
-            `,
-          }),
-        ),
-      ).toEqual({ a: 1 });
-      expect(
-        stripSymbols(
-          proxy.readQuery({
-            query: gql`
-              {
-                b
-                c
-              }
-            `,
-          }),
-        ),
-      ).toEqual({ b: 2, c: 3 });
-      expect(
-        stripSymbols(
-          proxy.readQuery({
-            query: gql`
-              {
-                a
-                b
-                c
-              }
-            `,
-          }),
-        ),
-      ).toEqual({ a: 1, b: 2, c: 3 });
-    });
-
-    it('will read some deeply nested data from the store', () => {
-      const proxy = createCache({
-        initialState: {
-          apollo: {
-            data: {
-              ROOT_QUERY: {
-                a: 1,
-                b: 2,
-                c: 3,
-                d: {
-                  type: 'id',
-                  id: 'foo',
-                  generated: false,
-                },
-              },
-              foo: {
-                e: 4,
-                f: 5,
-                g: 6,
-                h: {
-                  type: 'id',
-                  id: 'bar',
-                  generated: false,
-                },
-              },
-              bar: {
-                i: 7,
-                j: 8,
-                k: 9,
-              },
-            },
-          },
-        },
-      });
-
-      expect(
-        stripSymbols(
-          proxy.readQuery({
-            query: gql`
-              {
-                a
-                d {
-                  e
-                }
-              }
-            `,
-          }),
-        ),
-      ).toEqual({ a: 1, d: { e: 4 } });
-      expect(
-        stripSymbols(
-          proxy.readQuery({
-            query: gql`
-              {
-                a
-                d {
-                  e
-                  h {
-                    i
-                  }
-                }
-              }
-            `,
-          }),
-        ),
-      ).toEqual({ a: 1, d: { e: 4, h: { i: 7 } } });
-      expect(
-        stripSymbols(
-          proxy.readQuery({
-            query: gql`
-              {
-                a
-                b
-                c
-                d {
-                  e
-                  f
-                  g
-                  h {
-                    i
-                    j
-                    k
-                  }
-                }
-              }
-            `,
-          }),
-        ),
-      ).toEqual({
-        a: 1,
-        b: 2,
-        c: 3,
-        d: { e: 4, f: 5, g: 6, h: { i: 7, j: 8, k: 9 } },
-      });
-    });
-
-    it('will read some data from the store with variables', () => {
-      const proxy = createCache({
-        initialState: {
-          apollo: {
-            data: {
-              ROOT_QUERY: {
-                'field({"literal":true,"value":42})': 1,
-                'field({"literal":false,"value":42})': 2,
-              },
-            },
-          },
-        },
-      });
-
-      expect(
-        stripSymbols(
-          proxy.readQuery({
-            query: gql`
-              query($literal: Boolean, $value: Int) {
-                a: field(literal: true, value: 42)
-                b: field(literal: $literal, value: $value)
-              }
-            `,
-            variables: {
-              literal: false,
-              value: 42,
-            },
-          }),
-        ),
-      ).toEqual({ a: 1, b: 2 });
-    });
-
-    it('will read some data from the store with null variables', () => {
-      const proxy = createCache({
-        initialState: {
-          apollo: {
-            data: {
-              ROOT_QUERY: {
-                'field({"literal":false,"value":null})': 1,
-              },
-            },
-          },
-        },
-      });
-
-      expect(
-        stripSymbols(
-          proxy.readQuery({
-            query: gql`
-              query($literal: Boolean, $value: Int) {
-                a: field(literal: $literal, value: $value)
-              }
-            `,
-            variables: {
-              literal: false,
-              value: null,
-            },
-          }),
-        ),
-      ).toEqual({ a: 1 });
-    });
-
-    it('should not mutate arguments passed in', () => {
-      const proxy = createCache({
-        initialState: {
-          apollo: {
-            data: {
-              ROOT_QUERY: {
-                'field({"literal":true,"value":42})': 1,
-                'field({"literal":false,"value":42})': 2,
-              },
-            },
-          },
-        },
-      });
-
-      const options = {
-        query: gql`
-          query($literal: Boolean, $value: Int) {
-            a: field(literal: true, value: 42)
-            b: field(literal: $literal, value: $value)
-          }
-        `,
-        variables: {
-          literal: false,
-          value: 42,
-        },
-      };
-
-      const preQueryCopy = cloneDeep(options);
-      expect(stripSymbols(proxy.readQuery(options))).toEqual({ a: 1, b: 2 });
-      expect(preQueryCopy).toEqual(options);
-    });
-  });
-
-  describe('readFragment', () => {
-    it('will throw an error when there is no fragment', () => {
-      const proxy = createCache();
-
-      expect(() => {
-        proxy.readFragment({
-          id: 'x',
-          fragment: gql`
-            query {
-              a
-              b
-              c
-            }
-          `,
-        });
-      }).toThrowError(
-        'Found a query operation. No operations are allowed when using a fragment as a query. Only fragments are allowed.',
-      );
-      expect(() => {
-        proxy.readFragment({
-          id: 'x',
-          fragment: gql`
-            schema {
-              query: Query
-            }
-          `,
-        });
-      }).toThrowError(
-        'Found 0 fragments. `fragmentName` must be provided when there is not exactly 1 fragment.',
-      );
-    });
-
-    it('will throw an error when there is more than one fragment but no fragment name', () => {
-      const proxy = createCache();
-
-      expect(() => {
-        proxy.readFragment({
-          id: 'x',
-          fragment: gql`
-            fragment a on A {
-              a
-            }
-
-            fragment b on B {
-              b
-            }
-          `,
-        });
-      }).toThrowError(
-        'Found 2 fragments. `fragmentName` must be provided when there is not exactly 1 fragment.',
-      );
-      expect(() => {
-        proxy.readFragment({
-          id: 'x',
-          fragment: gql`
-            fragment a on A {
-              a
-            }
-
-            fragment b on B {
-              b
-            }
-
-            fragment c on C {
-              c
-            }
-          `,
-        });
-      }).toThrowError(
-        'Found 3 fragments. `fragmentName` must be provided when there is not exactly 1 fragment.',
-      );
-    });
-
-    it('will read some deeply nested data from the store at any id', () => {
-      const proxy = createCache({
-        initialState: {
-          apollo: {
-            data: {
-              ROOT_QUERY: {
-                __typename: 'Type1',
-                a: 1,
-                b: 2,
-                c: 3,
-                d: {
-                  type: 'id',
-                  id: 'foo',
-                  generated: false,
-                },
-              },
-              foo: {
-                __typename: 'Foo',
-                e: 4,
-                f: 5,
-                g: 6,
-                h: {
-                  type: 'id',
-                  id: 'bar',
-                  generated: false,
-                },
-              },
-              bar: {
-                __typename: 'Bar',
-                i: 7,
-                j: 8,
-                k: 9,
-              },
-            },
-          },
-        },
-      });
-
-      expect(
-        stripSymbols(
-          proxy.readFragment({
-            id: 'foo',
-            fragment: gql`
-              fragment fragmentFoo on Foo {
-                e
-                h {
-                  i
-                }
-              }
-            `,
-          }),
-        ),
-      ).toEqual({ e: 4, h: { i: 7 } });
-      expect(
-        stripSymbols(
-          proxy.readFragment({
-            id: 'foo',
-            fragment: gql`
-              fragment fragmentFoo on Foo {
-                e
-                f
-                g
-                h {
-                  i
-                  j
-                  k
-                }
-              }
-            `,
-          }),
-        ),
-      ).toEqual({ e: 4, f: 5, g: 6, h: { i: 7, j: 8, k: 9 } });
-      expect(
-        stripSymbols(
-          proxy.readFragment({
-            id: 'bar',
-            fragment: gql`
-              fragment fragmentBar on Bar {
-                i
-              }
-            `,
-          }),
-        ),
-      ).toEqual({ i: 7 });
-      expect(
-        stripSymbols(
-          proxy.readFragment({
-            id: 'bar',
-            fragment: gql`
-              fragment fragmentBar on Bar {
-                i
-                j
-                k
-              }
-            `,
-          }),
-        ),
-      ).toEqual({ i: 7, j: 8, k: 9 });
-      expect(
-        stripSymbols(
-          proxy.readFragment({
-            id: 'foo',
-            fragment: gql`
-              fragment fragmentFoo on Foo {
-                e
-                f
-                g
-                h {
-                  i
-                  j
-                  k
-                }
-              }
-
-              fragment fragmentBar on Bar {
-                i
-                j
-                k
-              }
-            `,
-            fragmentName: 'fragmentFoo',
-          }),
-        ),
-      ).toEqual({ e: 4, f: 5, g: 6, h: { i: 7, j: 8, k: 9 } });
-      expect(
-        stripSymbols(
-          proxy.readFragment({
-            id: 'bar',
-            fragment: gql`
-              fragment fragmentFoo on Foo {
-                e
-                f
-                g
-                h {
-                  i
-                  j
-                  k
-                }
-              }
-
-              fragment fragmentBar on Bar {
-                i
-                j
-                k
-              }
-            `,
-            fragmentName: 'fragmentBar',
-          }),
-        ),
-      ).toEqual({ i: 7, j: 8, k: 9 });
-    });
-
-    it('will read some data from the store with variables', () => {
-      const proxy = createCache({
-        initialState: {
-          apollo: {
-            data: {
-              foo: {
-                __typename: 'Foo',
-                'field({"literal":true,"value":42})': 1,
-                'field({"literal":false,"value":42})': 2,
-              },
-            },
-          },
-        },
-      });
-
-      expect(
-        stripSymbols(
-          proxy.readFragment({
-            id: 'foo',
-            fragment: gql`
-              fragment foo on Foo {
-                a: field(literal: true, value: 42)
-                b: field(literal: $literal, value: $value)
-              }
-            `,
-            variables: {
-              literal: false,
-              value: 42,
-            },
-          }),
-        ),
-      ).toEqual({ a: 1, b: 2 });
-    });
-
-    it('will return null when an id that can’t be found is provided', () => {
-      const client1 = createCache();
-      const client2 = createCache({
-        initialState: {
-          apollo: {
-            data: {
-              bar: { __typename: 'Bar', a: 1, b: 2, c: 3 },
-            },
-          },
-        },
-      });
-      const client3 = createCache({
-        initialState: {
-          apollo: {
-            data: {
-              foo: { __typename: 'Foo', a: 1, b: 2, c: 3 },
-            },
-          },
-        },
-      });
-
-      expect(
-        stripSymbols(
-          client1.readFragment({
-            id: 'foo',
-            fragment: gql`
-              fragment fooFragment on Foo {
-                a
-                b
-                c
-              }
-            `,
-          }),
-        ),
-      ).toEqual(null);
-      expect(
-        stripSymbols(
-          client2.readFragment({
-            id: 'foo',
-            fragment: gql`
-              fragment fooFragment on Foo {
-                a
-                b
-                c
-              }
-            `,
-          }),
-        ),
-      ).toEqual(null);
-      expect(
-        stripSymbols(
-          client3.readFragment({
-            id: 'foo',
-            fragment: gql`
-              fragment fooFragment on Foo {
-                a
-                b
-                c
-              }
-            `,
-          }),
-        ),
-      ).toEqual({ a: 1, b: 2, c: 3 });
-    });
-  });
-
-  describe('writeQuery', () => {
-    it('will write some data to the store', () => {
-      const proxy = createCache();
-
-      proxy.writeQuery({
-        data: { a: 1 },
-        query: gql`
-          {
-            a
-          }
-        `,
-      });
-
-      expect((proxy as InMemoryCache).extract()).toEqual({
-        ROOT_QUERY: {
-          a: 1,
-        },
-      });
-
-      proxy.writeQuery({
-        data: { b: 2, c: 3 },
-        query: gql`
-          {
-            b
-            c
-          }
-        `,
-      });
-
-      expect((proxy as InMemoryCache).extract()).toEqual({
-        ROOT_QUERY: {
-          a: 1,
-          b: 2,
-          c: 3,
-        },
-      });
-
-      proxy.writeQuery({
-        data: { a: 4, b: 5, c: 6 },
-        query: gql`
-          {
-            a
-            b
-            c
-          }
-        `,
-      });
-
-      expect((proxy as InMemoryCache).extract()).toEqual({
-        ROOT_QUERY: {
-          a: 4,
-          b: 5,
-          c: 6,
-        },
-      });
-    });
-
-    it('will write some deeply nested data to the store', () => {
-      const proxy = createCache();
-
-      proxy.writeQuery({
-        data: { a: 1, d: { e: 4 } },
-        query: gql`
-          {
-            a
-            d {
-              e
-            }
-          }
-        `,
-      });
-
-      expect((proxy as InMemoryCache).extract()).toEqual({
-        ROOT_QUERY: {
-          a: 1,
-          d: {
-            type: 'id',
-            id: '$ROOT_QUERY.d',
-            generated: true,
-          },
-        },
-        '$ROOT_QUERY.d': {
-          e: 4,
-        },
-      });
-
-      proxy.writeQuery({
-        data: { a: 1, d: { h: { i: 7 } } },
-        query: gql`
-          {
-            a
-            d {
-              h {
-                i
-              }
-            }
-          }
-        `,
-      });
-
-      expect((proxy as InMemoryCache).extract()).toEqual({
-        ROOT_QUERY: {
-          a: 1,
-          d: {
-            type: 'id',
-            id: '$ROOT_QUERY.d',
-            generated: true,
-          },
-        },
-        '$ROOT_QUERY.d': {
-          e: 4,
-          h: {
-            type: 'id',
-            id: '$ROOT_QUERY.d.h',
-            generated: true,
-          },
-        },
-        '$ROOT_QUERY.d.h': {
-          i: 7,
-        },
-      });
-
-      proxy.writeQuery({
-        data: {
-          a: 1,
-          b: 2,
-          c: 3,
-          d: { e: 4, f: 5, g: 6, h: { i: 7, j: 8, k: 9 } },
-        },
-        query: gql`
-          {
-            a
-            b
-            c
-            d {
-              e
-              f
-              g
-              h {
-                i
-                j
-                k
-              }
-            }
-          }
-        `,
-      });
-
-      expect((proxy as InMemoryCache).extract()).toEqual({
-        ROOT_QUERY: {
-          a: 1,
-          b: 2,
-          c: 3,
-          d: {
-            type: 'id',
-            id: '$ROOT_QUERY.d',
-            generated: true,
-          },
-        },
-        '$ROOT_QUERY.d': {
-          e: 4,
-          f: 5,
-          g: 6,
-          h: {
-            type: 'id',
-            id: '$ROOT_QUERY.d.h',
-            generated: true,
-          },
-        },
-        '$ROOT_QUERY.d.h': {
-          i: 7,
-          j: 8,
-          k: 9,
-        },
-      });
-    });
-
-    it('will write some data to the store with variables', () => {
-      const proxy = createCache();
-
-      proxy.writeQuery({
-        data: {
-          a: 1,
-          b: 2,
-        },
-        query: gql`
-          query($literal: Boolean, $value: Int) {
-            a: field(literal: true, value: 42)
-            b: field(literal: $literal, value: $value)
-          }
-        `,
-        variables: {
-          literal: false,
-          value: 42,
-        },
-      });
-
-      expect((proxy as InMemoryCache).extract()).toEqual({
-        ROOT_QUERY: {
-          'field({"literal":true,"value":42})': 1,
-          'field({"literal":false,"value":42})': 2,
-        },
-      });
-    });
-    it('will write some data to the store with variables where some are null', () => {
-      const proxy = createCache();
-
-      proxy.writeQuery({
-        data: {
-          a: 1,
-          b: 2,
-        },
-        query: gql`
-          query($literal: Boolean, $value: Int) {
-            a: field(literal: true, value: 42)
-            b: field(literal: $literal, value: $value)
-          }
-        `,
-        variables: {
-          literal: false,
-          value: null,
-        },
-      });
-
-      expect((proxy as InMemoryCache).extract()).toEqual({
-        ROOT_QUERY: {
-          'field({"literal":true,"value":42})': 1,
-          'field({"literal":false,"value":null})': 2,
-        },
-      });
-    });
-  });
-
-  describe('writeFragment', () => {
-    it('will throw an error when there is no fragment', () => {
-      const proxy = createCache();
-
-      expect(() => {
-        proxy.writeFragment({
-          data: {},
-          id: 'x',
-          fragment: gql`
-            query {
-              a
-              b
-              c
-            }
-          `,
-        });
-      }).toThrowError(
-        'Found a query operation. No operations are allowed when using a fragment as a query. Only fragments are allowed.',
-      );
-      expect(() => {
-        proxy.writeFragment({
-          data: {},
-          id: 'x',
-          fragment: gql`
-            schema {
-              query: Query
-            }
-          `,
-        });
-      }).toThrowError(
-        'Found 0 fragments. `fragmentName` must be provided when there is not exactly 1 fragment.',
-      );
-    });
-
-    it('will throw an error when there is more than one fragment but no fragment name', () => {
-      const proxy = createCache();
-
-      expect(() => {
-        proxy.writeFragment({
-          data: {},
-          id: 'x',
-          fragment: gql`
-            fragment a on A {
-              a
-            }
-
-            fragment b on B {
-              b
-            }
-          `,
-        });
-      }).toThrowError(
-        'Found 2 fragments. `fragmentName` must be provided when there is not exactly 1 fragment.',
-      );
-      expect(() => {
-        proxy.writeFragment({
-          data: {},
-          id: 'x',
-          fragment: gql`
-            fragment a on A {
-              a
-            }
-
-            fragment b on B {
-              b
-            }
-
-            fragment c on C {
-              c
-            }
-          `,
-        });
-      }).toThrowError(
-        'Found 3 fragments. `fragmentName` must be provided when there is not exactly 1 fragment.',
-      );
-    });
-
-    it('will write some deeply nested data into the store at any id', () => {
-      const proxy = createCache({
-        config: { dataIdFromObject: (o: any) => o.id, addTypename: false },
-      });
-
-      proxy.writeFragment({
-        data: { __typename: 'Foo', e: 4, h: { id: 'bar', i: 7 } },
-        id: 'foo',
-        fragment: gql`
-          fragment fragmentFoo on Foo {
-            e
-            h {
-              i
-            }
-          }
-        `,
-      });
-
-      expect((proxy as InMemoryCache).extract()).toMatchSnapshot();
-      proxy.writeFragment({
-        data: { __typename: 'Foo', f: 5, g: 6, h: { id: 'bar', j: 8, k: 9 } },
-        id: 'foo',
-        fragment: gql`
-          fragment fragmentFoo on Foo {
-            f
-            g
-            h {
-              j
-              k
-            }
-          }
-        `,
-      });
-
-      expect((proxy as InMemoryCache).extract()).toMatchSnapshot();
-
-      proxy.writeFragment({
-        data: { i: 10, __typename: 'Bar' },
-        id: 'bar',
-        fragment: gql`
-          fragment fragmentBar on Bar {
-            i
-          }
-        `,
-      });
-
-      expect((proxy as InMemoryCache).extract()).toMatchSnapshot();
-
-      proxy.writeFragment({
-        data: { j: 11, k: 12, __typename: 'Bar' },
-        id: 'bar',
-        fragment: gql`
-          fragment fragmentBar on Bar {
-            j
-            k
-          }
-        `,
-      });
-
-      expect((proxy as InMemoryCache).extract()).toMatchSnapshot();
-
-      proxy.writeFragment({
-        data: {
-          __typename: 'Foo',
-          e: 4,
-          f: 5,
-          g: 6,
-          h: { __typename: 'Bar', id: 'bar', i: 7, j: 8, k: 9 },
-        },
-        id: 'foo',
-        fragment: gql`
-          fragment fooFragment on Foo {
-            e
-            f
-            g
-            h {
-              i
-              j
-              k
-            }
-          }
-
-          fragment barFragment on Bar {
-            i
-            j
-            k
-          }
-        `,
-        fragmentName: 'fooFragment',
-      });
-
-      expect((proxy as InMemoryCache).extract()).toMatchSnapshot();
-
-      proxy.writeFragment({
-        data: { __typename: 'Bar', i: 10, j: 11, k: 12 },
-        id: 'bar',
-        fragment: gql`
-          fragment fooFragment on Foo {
-            e
-            f
-            g
-            h {
-              i
-              j
-              k
-            }
-          }
-
-          fragment barFragment on Bar {
-            i
-            j
-            k
-          }
-        `,
-        fragmentName: 'barFragment',
-      });
-
-      expect((proxy as InMemoryCache).extract()).toMatchSnapshot();
-    });
-    it('writes data that can be read back', () => {
-      const proxy = createCache({
-        config: { addTypename: true },
-      });
-      const readWriteFragment = gql`
-        fragment aFragment on query {
-          getSomething {
-            id
-          }
-        }
-      `;
-      const data = {
-        __typename: 'query',
-        getSomething: { id: '123', __typename: 'Something' },
-      };
-      proxy.writeFragment({
-        data,
-        id: 'query',
-        fragment: readWriteFragment,
-      });
-
-      const result = proxy.readFragment({
-        fragment: readWriteFragment,
-        id: 'query',
-      });
-      expect(stripSymbols(result)).toEqual(data);
-    });
-
-    it('will write some data to the store with variables', () => {
-      const proxy = createCache({
-        config: { addTypename: true },
-      });
-
-      proxy.writeFragment({
-        data: {
-          a: 1,
-          b: 2,
-          __typename: 'Foo',
-        },
-        id: 'foo',
-        fragment: gql`
-          fragment foo on Foo {
-            a: field(literal: true, value: 42)
-            b: field(literal: $literal, value: $value)
-          }
-        `,
-        variables: {
-          literal: false,
-          value: 42,
-        },
-      });
-
-      expect((proxy as InMemoryCache).extract()).toEqual({
-        foo: {
-          __typename: 'Foo',
-          'field({"literal":true,"value":42})': 1,
-          'field({"literal":false,"value":42})': 2,
-        },
-      });
-    });
-  });
-
-  describe('performTransaction', () => {
-    it('will not broadcast mid-transaction', () => {
-      const cache = createCache();
-
-      let numBroadcasts = 0;
-
-      const query = gql`
-        {
-          a
-        }
-      `;
-
-      cache.watch({
-        query,
-        optimistic: false,
-        callback: () => {
-          numBroadcasts++;
-        },
-      });
-
-      expect(numBroadcasts).toEqual(0);
-
-      cache.performTransaction(proxy => {
-        proxy.writeQuery({
-          data: { a: 1 },
-          query,
-        });
-
-        expect(numBroadcasts).toEqual(0);
-
-        proxy.writeQuery({
-          data: { a: 4, b: 5, c: 6 },
-          query: gql`
-            {
-              a
-              b
-              c
-            }
-          `,
-        });
-
-        expect(numBroadcasts).toEqual(0);
-      });
-
-      expect(numBroadcasts).toEqual(1);
-    });
-  });
-
-  describe('performOptimisticTransaction', () => {
-    it('will only broadcast once', () => {
-      const cache = createCache();
-
-      let numBroadcasts = 0;
-
-      const query = gql`
-        {
-          a
-        }
-      `;
-
-      cache.watch({
-        query,
-        optimistic: true,
-        callback: () => {
-          numBroadcasts++;
-        },
-      });
-
-      expect(numBroadcasts).toEqual(0);
-
-      cache.recordOptimisticTransaction(proxy => {
-        proxy.writeQuery({
-          data: { a: 1 },
-          query,
-        });
-
-        expect(numBroadcasts).toEqual(0);
-
-        proxy.writeQuery({
-          data: { a: 4, b: 5, c: 6 },
-          query: gql`
-            {
-              a
-              b
-              c
-            }
-          `,
-        });
-
-        expect(numBroadcasts).toEqual(0);
-      }, 1);
-
-      expect(numBroadcasts).toEqual(1);
-    });
-  });
-});
+import { ApolloCache } from 'apollo-cache';
+import gql, { disableFragmentWarnings } from 'graphql-tag';
+import { stripSymbols } from 'apollo-utilities';
+import { cloneDeep } from 'lodash';
+
+import { InMemoryCache, ApolloReducerConfig, NormalizedCache } from '..';
+
+disableFragmentWarnings();
+
+describe('Cache', () => {
+  function createCache({
+    initialState,
+    config,
+  }: {
+    initialState?: any;
+    config?: ApolloReducerConfig;
+  } = {}): ApolloCache<NormalizedCache> {
+    return new InMemoryCache(
+      config || { addTypename: false },
+      // XXX this is the old format. The tests need to be updated but since it is mapped down
+    ).restore(initialState ? initialState.apollo.data : {});
+  }
+
+  describe('readQuery', () => {
+    it('will read some data from the store', () => {
+      const proxy = createCache({
+        initialState: {
+          apollo: {
+            data: {
+              ROOT_QUERY: {
+                a: 1,
+                b: 2,
+                c: 3,
+              },
+            },
+          },
+        },
+      });
+      expect(
+        stripSymbols(
+          proxy.readQuery({
+            query: gql`
+              {
+                a
+              }
+            `,
+          }),
+        ),
+      ).toEqual({ a: 1 });
+      expect(
+        stripSymbols(
+          proxy.readQuery({
+            query: gql`
+              {
+                b
+                c
+              }
+            `,
+          }),
+        ),
+      ).toEqual({ b: 2, c: 3 });
+      expect(
+        stripSymbols(
+          proxy.readQuery({
+            query: gql`
+              {
+                a
+                b
+                c
+              }
+            `,
+          }),
+        ),
+      ).toEqual({ a: 1, b: 2, c: 3 });
+    });
+
+    it('will read some deeply nested data from the store', () => {
+      const proxy = createCache({
+        initialState: {
+          apollo: {
+            data: {
+              ROOT_QUERY: {
+                a: 1,
+                b: 2,
+                c: 3,
+                d: {
+                  type: 'id',
+                  id: 'foo',
+                  generated: false,
+                },
+              },
+              foo: {
+                e: 4,
+                f: 5,
+                g: 6,
+                h: {
+                  type: 'id',
+                  id: 'bar',
+                  generated: false,
+                },
+              },
+              bar: {
+                i: 7,
+                j: 8,
+                k: 9,
+              },
+            },
+          },
+        },
+      });
+
+      expect(
+        stripSymbols(
+          proxy.readQuery({
+            query: gql`
+              {
+                a
+                d {
+                  e
+                }
+              }
+            `,
+          }),
+        ),
+      ).toEqual({ a: 1, d: { e: 4 } });
+      expect(
+        stripSymbols(
+          proxy.readQuery({
+            query: gql`
+              {
+                a
+                d {
+                  e
+                  h {
+                    i
+                  }
+                }
+              }
+            `,
+          }),
+        ),
+      ).toEqual({ a: 1, d: { e: 4, h: { i: 7 } } });
+      expect(
+        stripSymbols(
+          proxy.readQuery({
+            query: gql`
+              {
+                a
+                b
+                c
+                d {
+                  e
+                  f
+                  g
+                  h {
+                    i
+                    j
+                    k
+                  }
+                }
+              }
+            `,
+          }),
+        ),
+      ).toEqual({
+        a: 1,
+        b: 2,
+        c: 3,
+        d: { e: 4, f: 5, g: 6, h: { i: 7, j: 8, k: 9 } },
+      });
+    });
+
+    it('will read some data from the store with variables', () => {
+      const proxy = createCache({
+        initialState: {
+          apollo: {
+            data: {
+              ROOT_QUERY: {
+                'field({"literal":true,"value":42})': 1,
+                'field({"literal":false,"value":42})': 2,
+              },
+            },
+          },
+        },
+      });
+
+      expect(
+        stripSymbols(
+          proxy.readQuery({
+            query: gql`
+              query($literal: Boolean, $value: Int) {
+                a: field(literal: true, value: 42)
+                b: field(literal: $literal, value: $value)
+              }
+            `,
+            variables: {
+              literal: false,
+              value: 42,
+            },
+          }),
+        ),
+      ).toEqual({ a: 1, b: 2 });
+    });
+
+    it('will read some data from the store with null variables', () => {
+      const proxy = createCache({
+        initialState: {
+          apollo: {
+            data: {
+              ROOT_QUERY: {
+                'field({"literal":false,"value":null})': 1,
+              },
+            },
+          },
+        },
+      });
+
+      expect(
+        stripSymbols(
+          proxy.readQuery({
+            query: gql`
+              query($literal: Boolean, $value: Int) {
+                a: field(literal: $literal, value: $value)
+              }
+            `,
+            variables: {
+              literal: false,
+              value: null,
+            },
+          }),
+        ),
+      ).toEqual({ a: 1 });
+    });
+
+    it('should not mutate arguments passed in', () => {
+      const proxy = createCache({
+        initialState: {
+          apollo: {
+            data: {
+              ROOT_QUERY: {
+                'field({"literal":true,"value":42})': 1,
+                'field({"literal":false,"value":42})': 2,
+              },
+            },
+          },
+        },
+      });
+
+      const options = {
+        query: gql`
+          query($literal: Boolean, $value: Int) {
+            a: field(literal: true, value: 42)
+            b: field(literal: $literal, value: $value)
+          }
+        `,
+        variables: {
+          literal: false,
+          value: 42,
+        },
+      };
+
+      const preQueryCopy = cloneDeep(options);
+      expect(stripSymbols(proxy.readQuery(options))).toEqual({ a: 1, b: 2 });
+      expect(preQueryCopy).toEqual(options);
+    });
+  });
+
+  describe('readFragment', () => {
+    it('will throw an error when there is no fragment', () => {
+      const proxy = createCache();
+
+      expect(() => {
+        proxy.readFragment({
+          id: 'x',
+          fragment: gql`
+            query {
+              a
+              b
+              c
+            }
+          `,
+        });
+      }).toThrowError(
+        'Found a query operation. No operations are allowed when using a fragment as a query. Only fragments are allowed.',
+      );
+      expect(() => {
+        proxy.readFragment({
+          id: 'x',
+          fragment: gql`
+            schema {
+              query: Query
+            }
+          `,
+        });
+      }).toThrowError(
+        'Found 0 fragments. `fragmentName` must be provided when there is not exactly 1 fragment.',
+      );
+    });
+
+    it('will throw an error when there is more than one fragment but no fragment name', () => {
+      const proxy = createCache();
+
+      expect(() => {
+        proxy.readFragment({
+          id: 'x',
+          fragment: gql`
+            fragment a on A {
+              a
+            }
+
+            fragment b on B {
+              b
+            }
+          `,
+        });
+      }).toThrowError(
+        'Found 2 fragments. `fragmentName` must be provided when there is not exactly 1 fragment.',
+      );
+      expect(() => {
+        proxy.readFragment({
+          id: 'x',
+          fragment: gql`
+            fragment a on A {
+              a
+            }
+
+            fragment b on B {
+              b
+            }
+
+            fragment c on C {
+              c
+            }
+          `,
+        });
+      }).toThrowError(
+        'Found 3 fragments. `fragmentName` must be provided when there is not exactly 1 fragment.',
+      );
+    });
+
+    it('will read some deeply nested data from the store at any id', () => {
+      const proxy = createCache({
+        initialState: {
+          apollo: {
+            data: {
+              ROOT_QUERY: {
+                __typename: 'Type1',
+                a: 1,
+                b: 2,
+                c: 3,
+                d: {
+                  type: 'id',
+                  id: 'foo',
+                  generated: false,
+                },
+              },
+              foo: {
+                __typename: 'Foo',
+                e: 4,
+                f: 5,
+                g: 6,
+                h: {
+                  type: 'id',
+                  id: 'bar',
+                  generated: false,
+                },
+              },
+              bar: {
+                __typename: 'Bar',
+                i: 7,
+                j: 8,
+                k: 9,
+              },
+            },
+          },
+        },
+      });
+
+      expect(
+        stripSymbols(
+          proxy.readFragment({
+            id: 'foo',
+            fragment: gql`
+              fragment fragmentFoo on Foo {
+                e
+                h {
+                  i
+                }
+              }
+            `,
+          }),
+        ),
+      ).toEqual({ e: 4, h: { i: 7 } });
+      expect(
+        stripSymbols(
+          proxy.readFragment({
+            id: 'foo',
+            fragment: gql`
+              fragment fragmentFoo on Foo {
+                e
+                f
+                g
+                h {
+                  i
+                  j
+                  k
+                }
+              }
+            `,
+          }),
+        ),
+      ).toEqual({ e: 4, f: 5, g: 6, h: { i: 7, j: 8, k: 9 } });
+      expect(
+        stripSymbols(
+          proxy.readFragment({
+            id: 'bar',
+            fragment: gql`
+              fragment fragmentBar on Bar {
+                i
+              }
+            `,
+          }),
+        ),
+      ).toEqual({ i: 7 });
+      expect(
+        stripSymbols(
+          proxy.readFragment({
+            id: 'bar',
+            fragment: gql`
+              fragment fragmentBar on Bar {
+                i
+                j
+                k
+              }
+            `,
+          }),
+        ),
+      ).toEqual({ i: 7, j: 8, k: 9 });
+      expect(
+        stripSymbols(
+          proxy.readFragment({
+            id: 'foo',
+            fragment: gql`
+              fragment fragmentFoo on Foo {
+                e
+                f
+                g
+                h {
+                  i
+                  j
+                  k
+                }
+              }
+
+              fragment fragmentBar on Bar {
+                i
+                j
+                k
+              }
+            `,
+            fragmentName: 'fragmentFoo',
+          }),
+        ),
+      ).toEqual({ e: 4, f: 5, g: 6, h: { i: 7, j: 8, k: 9 } });
+      expect(
+        stripSymbols(
+          proxy.readFragment({
+            id: 'bar',
+            fragment: gql`
+              fragment fragmentFoo on Foo {
+                e
+                f
+                g
+                h {
+                  i
+                  j
+                  k
+                }
+              }
+
+              fragment fragmentBar on Bar {
+                i
+                j
+                k
+              }
+            `,
+            fragmentName: 'fragmentBar',
+          }),
+        ),
+      ).toEqual({ i: 7, j: 8, k: 9 });
+    });
+
+    it('will read some data from the store with variables', () => {
+      const proxy = createCache({
+        initialState: {
+          apollo: {
+            data: {
+              foo: {
+                __typename: 'Foo',
+                'field({"literal":true,"value":42})': 1,
+                'field({"literal":false,"value":42})': 2,
+              },
+            },
+          },
+        },
+      });
+
+      expect(
+        stripSymbols(
+          proxy.readFragment({
+            id: 'foo',
+            fragment: gql`
+              fragment foo on Foo {
+                a: field(literal: true, value: 42)
+                b: field(literal: $literal, value: $value)
+              }
+            `,
+            variables: {
+              literal: false,
+              value: 42,
+            },
+          }),
+        ),
+      ).toEqual({ a: 1, b: 2 });
+    });
+
+    it('will return null when an id that can’t be found is provided', () => {
+      const client1 = createCache();
+      const client2 = createCache({
+        initialState: {
+          apollo: {
+            data: {
+              bar: { __typename: 'Bar', a: 1, b: 2, c: 3 },
+            },
+          },
+        },
+      });
+      const client3 = createCache({
+        initialState: {
+          apollo: {
+            data: {
+              foo: { __typename: 'Foo', a: 1, b: 2, c: 3 },
+            },
+          },
+        },
+      });
+
+      expect(
+        stripSymbols(
+          client1.readFragment({
+            id: 'foo',
+            fragment: gql`
+              fragment fooFragment on Foo {
+                a
+                b
+                c
+              }
+            `,
+          }),
+        ),
+      ).toEqual(null);
+      expect(
+        stripSymbols(
+          client2.readFragment({
+            id: 'foo',
+            fragment: gql`
+              fragment fooFragment on Foo {
+                a
+                b
+                c
+              }
+            `,
+          }),
+        ),
+      ).toEqual(null);
+      expect(
+        stripSymbols(
+          client3.readFragment({
+            id: 'foo',
+            fragment: gql`
+              fragment fooFragment on Foo {
+                a
+                b
+                c
+              }
+            `,
+          }),
+        ),
+      ).toEqual({ a: 1, b: 2, c: 3 });
+    });
+  });
+
+  describe('writeQuery', () => {
+    it('will write some data to the store', () => {
+      const proxy = createCache();
+
+      proxy.writeQuery({
+        data: { a: 1 },
+        query: gql`
+          {
+            a
+          }
+        `,
+      });
+
+      expect((proxy as InMemoryCache).extract()).toEqual({
+        ROOT_QUERY: {
+          a: 1,
+        },
+      });
+
+      proxy.writeQuery({
+        data: { b: 2, c: 3 },
+        query: gql`
+          {
+            b
+            c
+          }
+        `,
+      });
+
+      expect((proxy as InMemoryCache).extract()).toEqual({
+        ROOT_QUERY: {
+          a: 1,
+          b: 2,
+          c: 3,
+        },
+      });
+
+      proxy.writeQuery({
+        data: { a: 4, b: 5, c: 6 },
+        query: gql`
+          {
+            a
+            b
+            c
+          }
+        `,
+      });
+
+      expect((proxy as InMemoryCache).extract()).toEqual({
+        ROOT_QUERY: {
+          a: 4,
+          b: 5,
+          c: 6,
+        },
+      });
+    });
+
+    it('will write some deeply nested data to the store', () => {
+      const proxy = createCache();
+
+      proxy.writeQuery({
+        data: { a: 1, d: { e: 4 } },
+        query: gql`
+          {
+            a
+            d {
+              e
+            }
+          }
+        `,
+      });
+
+      expect((proxy as InMemoryCache).extract()).toEqual({
+        ROOT_QUERY: {
+          a: 1,
+          d: {
+            type: 'id',
+            id: '$ROOT_QUERY.d',
+            generated: true,
+          },
+        },
+        '$ROOT_QUERY.d': {
+          e: 4,
+        },
+      });
+
+      proxy.writeQuery({
+        data: { a: 1, d: { h: { i: 7 } } },
+        query: gql`
+          {
+            a
+            d {
+              h {
+                i
+              }
+            }
+          }
+        `,
+      });
+
+      expect((proxy as InMemoryCache).extract()).toEqual({
+        ROOT_QUERY: {
+          a: 1,
+          d: {
+            type: 'id',
+            id: '$ROOT_QUERY.d',
+            generated: true,
+          },
+        },
+        '$ROOT_QUERY.d': {
+          e: 4,
+          h: {
+            type: 'id',
+            id: '$ROOT_QUERY.d.h',
+            generated: true,
+          },
+        },
+        '$ROOT_QUERY.d.h': {
+          i: 7,
+        },
+      });
+
+      proxy.writeQuery({
+        data: {
+          a: 1,
+          b: 2,
+          c: 3,
+          d: { e: 4, f: 5, g: 6, h: { i: 7, j: 8, k: 9 } },
+        },
+        query: gql`
+          {
+            a
+            b
+            c
+            d {
+              e
+              f
+              g
+              h {
+                i
+                j
+                k
+              }
+            }
+          }
+        `,
+      });
+
+      expect((proxy as InMemoryCache).extract()).toEqual({
+        ROOT_QUERY: {
+          a: 1,
+          b: 2,
+          c: 3,
+          d: {
+            type: 'id',
+            id: '$ROOT_QUERY.d',
+            generated: true,
+          },
+        },
+        '$ROOT_QUERY.d': {
+          e: 4,
+          f: 5,
+          g: 6,
+          h: {
+            type: 'id',
+            id: '$ROOT_QUERY.d.h',
+            generated: true,
+          },
+        },
+        '$ROOT_QUERY.d.h': {
+          i: 7,
+          j: 8,
+          k: 9,
+        },
+      });
+    });
+
+    it('will write some data to the store with variables', () => {
+      const proxy = createCache();
+
+      proxy.writeQuery({
+        data: {
+          a: 1,
+          b: 2,
+        },
+        query: gql`
+          query($literal: Boolean, $value: Int) {
+            a: field(literal: true, value: 42)
+            b: field(literal: $literal, value: $value)
+          }
+        `,
+        variables: {
+          literal: false,
+          value: 42,
+        },
+      });
+
+      expect((proxy as InMemoryCache).extract()).toEqual({
+        ROOT_QUERY: {
+          'field({"literal":true,"value":42})': 1,
+          'field({"literal":false,"value":42})': 2,
+        },
+      });
+    });
+    it('will write some data to the store with variables where some are null', () => {
+      const proxy = createCache();
+
+      proxy.writeQuery({
+        data: {
+          a: 1,
+          b: 2,
+        },
+        query: gql`
+          query($literal: Boolean, $value: Int) {
+            a: field(literal: true, value: 42)
+            b: field(literal: $literal, value: $value)
+          }
+        `,
+        variables: {
+          literal: false,
+          value: null,
+        },
+      });
+
+      expect((proxy as InMemoryCache).extract()).toEqual({
+        ROOT_QUERY: {
+          'field({"literal":true,"value":42})': 1,
+          'field({"literal":false,"value":null})': 2,
+        },
+      });
+    });
+  });
+
+  describe('writeFragment', () => {
+    it('will throw an error when there is no fragment', () => {
+      const proxy = createCache();
+
+      expect(() => {
+        proxy.writeFragment({
+          data: {},
+          id: 'x',
+          fragment: gql`
+            query {
+              a
+              b
+              c
+            }
+          `,
+        });
+      }).toThrowError(
+        'Found a query operation. No operations are allowed when using a fragment as a query. Only fragments are allowed.',
+      );
+      expect(() => {
+        proxy.writeFragment({
+          data: {},
+          id: 'x',
+          fragment: gql`
+            schema {
+              query: Query
+            }
+          `,
+        });
+      }).toThrowError(
+        'Found 0 fragments. `fragmentName` must be provided when there is not exactly 1 fragment.',
+      );
+    });
+
+    it('will throw an error when there is more than one fragment but no fragment name', () => {
+      const proxy = createCache();
+
+      expect(() => {
+        proxy.writeFragment({
+          data: {},
+          id: 'x',
+          fragment: gql`
+            fragment a on A {
+              a
+            }
+
+            fragment b on B {
+              b
+            }
+          `,
+        });
+      }).toThrowError(
+        'Found 2 fragments. `fragmentName` must be provided when there is not exactly 1 fragment.',
+      );
+      expect(() => {
+        proxy.writeFragment({
+          data: {},
+          id: 'x',
+          fragment: gql`
+            fragment a on A {
+              a
+            }
+
+            fragment b on B {
+              b
+            }
+
+            fragment c on C {
+              c
+            }
+          `,
+        });
+      }).toThrowError(
+        'Found 3 fragments. `fragmentName` must be provided when there is not exactly 1 fragment.',
+      );
+    });
+
+    it('will write some deeply nested data into the store at any id', () => {
+      const proxy = createCache({
+        config: { dataIdFromObject: (o: any) => o.id, addTypename: false },
+      });
+
+      proxy.writeFragment({
+        data: { __typename: 'Foo', e: 4, h: { id: 'bar', i: 7 } },
+        id: 'foo',
+        fragment: gql`
+          fragment fragmentFoo on Foo {
+            e
+            h {
+              i
+            }
+          }
+        `,
+      });
+
+      expect((proxy as InMemoryCache).extract()).toMatchSnapshot();
+      proxy.writeFragment({
+        data: { __typename: 'Foo', f: 5, g: 6, h: { id: 'bar', j: 8, k: 9 } },
+        id: 'foo',
+        fragment: gql`
+          fragment fragmentFoo on Foo {
+            f
+            g
+            h {
+              j
+              k
+            }
+          }
+        `,
+      });
+
+      expect((proxy as InMemoryCache).extract()).toMatchSnapshot();
+
+      proxy.writeFragment({
+        data: { i: 10, __typename: 'Bar' },
+        id: 'bar',
+        fragment: gql`
+          fragment fragmentBar on Bar {
+            i
+          }
+        `,
+      });
+
+      expect((proxy as InMemoryCache).extract()).toMatchSnapshot();
+
+      proxy.writeFragment({
+        data: { j: 11, k: 12, __typename: 'Bar' },
+        id: 'bar',
+        fragment: gql`
+          fragment fragmentBar on Bar {
+            j
+            k
+          }
+        `,
+      });
+
+      expect((proxy as InMemoryCache).extract()).toMatchSnapshot();
+
+      proxy.writeFragment({
+        data: {
+          __typename: 'Foo',
+          e: 4,
+          f: 5,
+          g: 6,
+          h: { __typename: 'Bar', id: 'bar', i: 7, j: 8, k: 9 },
+        },
+        id: 'foo',
+        fragment: gql`
+          fragment fooFragment on Foo {
+            e
+            f
+            g
+            h {
+              i
+              j
+              k
+            }
+          }
+
+          fragment barFragment on Bar {
+            i
+            j
+            k
+          }
+        `,
+        fragmentName: 'fooFragment',
+      });
+
+      expect((proxy as InMemoryCache).extract()).toMatchSnapshot();
+
+      proxy.writeFragment({
+        data: { __typename: 'Bar', i: 10, j: 11, k: 12 },
+        id: 'bar',
+        fragment: gql`
+          fragment fooFragment on Foo {
+            e
+            f
+            g
+            h {
+              i
+              j
+              k
+            }
+          }
+
+          fragment barFragment on Bar {
+            i
+            j
+            k
+          }
+        `,
+        fragmentName: 'barFragment',
+      });
+
+      expect((proxy as InMemoryCache).extract()).toMatchSnapshot();
+    });
+    it('writes data that can be read back', () => {
+      const proxy = createCache({
+        config: { addTypename: true },
+      });
+      const readWriteFragment = gql`
+        fragment aFragment on query {
+          getSomething {
+            id
+          }
+        }
+      `;
+      const data = {
+        __typename: 'query',
+        getSomething: { id: '123', __typename: 'Something' },
+      };
+      proxy.writeFragment({
+        data,
+        id: 'query',
+        fragment: readWriteFragment,
+      });
+
+      const result = proxy.readFragment({
+        fragment: readWriteFragment,
+        id: 'query',
+      });
+      expect(stripSymbols(result)).toEqual(data);
+    });
+
+    it('will write some data to the store with variables', () => {
+      const proxy = createCache({
+        config: { addTypename: true },
+      });
+
+      proxy.writeFragment({
+        data: {
+          a: 1,
+          b: 2,
+          __typename: 'Foo',
+        },
+        id: 'foo',
+        fragment: gql`
+          fragment foo on Foo {
+            a: field(literal: true, value: 42)
+            b: field(literal: $literal, value: $value)
+          }
+        `,
+        variables: {
+          literal: false,
+          value: 42,
+        },
+      });
+
+      expect((proxy as InMemoryCache).extract()).toEqual({
+        foo: {
+          __typename: 'Foo',
+          'field({"literal":true,"value":42})': 1,
+          'field({"literal":false,"value":42})': 2,
+        },
+      });
+    });
+  });
+
+  describe('performTransaction', () => {
+    it('will not broadcast mid-transaction', () => {
+      const cache = createCache();
+
+      let numBroadcasts = 0;
+
+      const query = gql`
+        {
+          a
+        }
+      `;
+
+      cache.watch({
+        query,
+        optimistic: false,
+        callback: () => {
+          numBroadcasts++;
+        },
+      });
+
+      expect(numBroadcasts).toEqual(0);
+
+      cache.performTransaction(proxy => {
+        proxy.writeQuery({
+          data: { a: 1 },
+          query,
+        });
+
+        expect(numBroadcasts).toEqual(0);
+
+        proxy.writeQuery({
+          data: { a: 4, b: 5, c: 6 },
+          query: gql`
+            {
+              a
+              b
+              c
+            }
+          `,
+        });
+
+        expect(numBroadcasts).toEqual(0);
+      });
+
+      expect(numBroadcasts).toEqual(1);
+    });
+  });
+
+  describe('performOptimisticTransaction', () => {
+    it('will only broadcast once', () => {
+      const cache = createCache();
+
+      let numBroadcasts = 0;
+
+      const query = gql`
+        {
+          a
+        }
+      `;
+
+      cache.watch({
+        query,
+        optimistic: true,
+        callback: () => {
+          numBroadcasts++;
+        },
+      });
+
+      expect(numBroadcasts).toEqual(0);
+
+      cache.recordOptimisticTransaction(proxy => {
+        proxy.writeQuery({
+          data: { a: 1 },
+          query,
+        });
+
+        expect(numBroadcasts).toEqual(0);
+
+        proxy.writeQuery({
+          data: { a: 4, b: 5, c: 6 },
+          query: gql`
+            {
+              a
+              b
+              c
+            }
+          `,
+        });
+
+        expect(numBroadcasts).toEqual(0);
+      }, 1);
+
+      expect(numBroadcasts).toEqual(1);
+    });
+  });
+});