From 7d84fc8caa8d0d88d9a5c8e015cc532172c43ad7 Mon Sep 17 00:00:00 2001
From: Fabian Schneider <fabbbbbi+git@googlemail.com>
Date: Sat, 19 Jan 2019 00:44:13 +0100
Subject: [PATCH 1/2] Fix cache policy calculation

---
 .../__tests__/cacheControlExtension.test.ts   | 63 +++++++++++++++++++
 packages/apollo-cache-control/src/index.ts    |  2 +-
 2 files changed, 64 insertions(+), 1 deletion(-)
 create mode 100644 packages/apollo-cache-control/src/__tests__/cacheControlExtension.test.ts

diff --git a/packages/apollo-cache-control/src/__tests__/cacheControlExtension.test.ts b/packages/apollo-cache-control/src/__tests__/cacheControlExtension.test.ts
new file mode 100644
index 00000000000..957c8c8bab9
--- /dev/null
+++ b/packages/apollo-cache-control/src/__tests__/cacheControlExtension.test.ts
@@ -0,0 +1,63 @@
+import { ResponsePath } from 'graphql';
+import { CacheControlExtension, CacheScope } from '../';
+
+describe('CacheControlExtension', () => {
+  let cacheControlExtension: CacheControlExtension;
+
+  beforeEach(() => {
+    cacheControlExtension = new CacheControlExtension();
+  });
+
+  describe('computeOverallCachePolicy', () => {
+    const responsePath: ResponsePath = {
+      key: 'test',
+      prev: undefined,
+    };
+    const responseSubPath: ResponsePath = {
+      key: 'subTest',
+      prev: responsePath,
+    };
+
+    it('returns undefined without cache hints', () => {
+      const cachePolicy = cacheControlExtension.computeOverallCachePolicy();
+      expect(cachePolicy).toBeUndefined();
+    });
+
+    it('returns lowest max age value', () => {
+      cacheControlExtension.addHint(responsePath, { maxAge: 10 });
+      cacheControlExtension.addHint(responseSubPath, { maxAge: 20 });
+
+      const cachePolicy = cacheControlExtension.computeOverallCachePolicy();
+      expect(cachePolicy).toHaveProperty('maxAge', 10);
+    });
+
+    it('returns undefined if any cache hint has a maxAge of 0', () => {
+      cacheControlExtension.addHint(responsePath, { maxAge: 120 });
+      cacheControlExtension.addHint(responseSubPath, { maxAge: 0 });
+
+      const cachePolicy = cacheControlExtension.computeOverallCachePolicy();
+      expect(cachePolicy).toBeUndefined();
+    });
+
+    it('returns PUBLIC scope by default', () => {
+      cacheControlExtension.addHint(responsePath, { maxAge: 10 });
+
+      const cachePolicy = cacheControlExtension.computeOverallCachePolicy();
+      expect(cachePolicy).toHaveProperty('scope', CacheScope.Public);
+    });
+
+    it('returns PRIVATE scope if any cache hint has PRIVATE scope', () => {
+      cacheControlExtension.addHint(responsePath, {
+        maxAge: 10,
+        scope: CacheScope.Public,
+      });
+      cacheControlExtension.addHint(responseSubPath, {
+        maxAge: 10,
+        scope: CacheScope.Private,
+      });
+
+      const cachePolicy = cacheControlExtension.computeOverallCachePolicy();
+      expect(cachePolicy).toHaveProperty('scope', CacheScope.Private);
+    });
+  });
+});
diff --git a/packages/apollo-cache-control/src/index.ts b/packages/apollo-cache-control/src/index.ts
index db145f7a15f..f6708e5ab51 100644
--- a/packages/apollo-cache-control/src/index.ts
+++ b/packages/apollo-cache-control/src/index.ts
@@ -156,7 +156,7 @@ export class CacheControlExtension<TContext = any>
     let scope: CacheScope = CacheScope.Public;
 
     for (const hint of this.hints.values()) {
-      if (hint.maxAge) {
+      if (hint.maxAge !== undefined) {
         lowestMaxAge = lowestMaxAge
           ? Math.min(lowestMaxAge, hint.maxAge)
           : hint.maxAge;

From 4312fe4c50792d2bcc004c0ada0099d76b8454dd Mon Sep 17 00:00:00 2001
From: Fabian Schneider <fabbbbbi+git@googlemail.com>
Date: Tue, 22 Jan 2019 08:30:17 +0100
Subject: [PATCH 2/2] Fix cache policy minimum calculation

---
 .../src/__tests__/cacheControlExtension.test.ts            | 5 +++++
 packages/apollo-cache-control/src/index.ts                 | 7 ++++---
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/packages/apollo-cache-control/src/__tests__/cacheControlExtension.test.ts b/packages/apollo-cache-control/src/__tests__/cacheControlExtension.test.ts
index 957c8c8bab9..127071f55e9 100644
--- a/packages/apollo-cache-control/src/__tests__/cacheControlExtension.test.ts
+++ b/packages/apollo-cache-control/src/__tests__/cacheControlExtension.test.ts
@@ -17,6 +17,10 @@ describe('CacheControlExtension', () => {
       key: 'subTest',
       prev: responsePath,
     };
+    const responseSubSubPath: ResponsePath = {
+      key: 'subSubTest',
+      prev: responseSubPath,
+    };
 
     it('returns undefined without cache hints', () => {
       const cachePolicy = cacheControlExtension.computeOverallCachePolicy();
@@ -34,6 +38,7 @@ describe('CacheControlExtension', () => {
     it('returns undefined if any cache hint has a maxAge of 0', () => {
       cacheControlExtension.addHint(responsePath, { maxAge: 120 });
       cacheControlExtension.addHint(responseSubPath, { maxAge: 0 });
+      cacheControlExtension.addHint(responseSubSubPath, { maxAge: 20 });
 
       const cachePolicy = cacheControlExtension.computeOverallCachePolicy();
       expect(cachePolicy).toBeUndefined();
diff --git a/packages/apollo-cache-control/src/index.ts b/packages/apollo-cache-control/src/index.ts
index f6708e5ab51..80d8cd23913 100644
--- a/packages/apollo-cache-control/src/index.ts
+++ b/packages/apollo-cache-control/src/index.ts
@@ -157,9 +157,10 @@ export class CacheControlExtension<TContext = any>
 
     for (const hint of this.hints.values()) {
       if (hint.maxAge !== undefined) {
-        lowestMaxAge = lowestMaxAge
-          ? Math.min(lowestMaxAge, hint.maxAge)
-          : hint.maxAge;
+        lowestMaxAge =
+          lowestMaxAge !== undefined
+            ? Math.min(lowestMaxAge, hint.maxAge)
+            : hint.maxAge;
       }
       if (hint.scope === CacheScope.Private) {
         scope = CacheScope.Private;