docs: update readme

Author: ardeois

.circleci/.config.yml

@@ -0,0 +1,41 @@
+# Javascript Node CircleCI 2.0 configuration file
+#
+# Check {{ '/2.0/language-javascript/' | docs_url }} for more details
+#
+version: 2
+
+defaults: &defaults
+  working_directory: ~/repo
+  docker:
+    - image: circleci/node:10
+
+jobs:
+  test:
+    <<: *defaults
+    steps:
+      - checkout
+
+      - restore_cache:
+          keys:
+            - v1-dependencies-{{ checksum "package.json" }}
+            - v1-dependencies-
+
+      - run: yarn install
+      - run:
+          name: Run tests
+          command: yarn test
+
+      - save_cache:
+          paths:
+            - node_modules
+          key: v1-dependencies-{{ checksum "package.json" }}
+
+      - persist_to_workspace:
+          root: ~/repo
+          paths: .
+
+workflows:
+  version: 2
+  only_test:
+    jobs:
+      - test

README.md

@@ -30,3 +30,55 @@ generates:
       - 'graphql-codegen-typescript-mock-data':
           typesFile: '../generated-types.ts'
 ```
+
+## Example or generated code
+
+Given the following schema:
+
+```graphql
+type Avatar {
+  id: ID!
+  url: String!
+}
+
+type User {
+  id: ID!
+  login: String!
+  avatar: Avatar
+}
+
+type Query {
+  user: User!
+}
+```
+
+The code generated will look like:
+
+```typescript
+export const anAvatar = (overrides?: Partial<Avatar>): Avatar => {
+  return {
+    id: '1550ff93-cd31-49b4-bc38-ef1cb68bdc38',
+    url: 'aliquid',
+    ...overrides,
+  };
+};
+
+export const aUser = (overrides?: Partial<User>): User => {
+  return {
+    id: 'b5756f00-51a6-422a-9a7d-c13ee6a63750',
+    login: 'libero',
+    avatar: anAvatar(),
+    ...overrides,
+  };
+};
+```
+
+### Usage in tests
+
+Those helper functions can be used in our unit tests:
+
+```typescript
+const user = aUser({ login: 'johndoe' });
+
+// will create a user object with `login` property overridden to `johndoe`
+```

tests/__snapshots__/typescript-mock-data.spec.ts.snap

@@ -4,19 +4,19 @@ exports[`should generate mock data functions 1`] = `
 "
 export const anAvatar = (overrides?: Partial<Avatar>): Avatar => {
     return {
-        id: '1550ff93-cd31-49b4-bc38-ef1cb68bdc38',
+        id: '0550ff93-dd31-49b4-8c38-ff1cb68bdc38',
         url: 'aliquid',
         ...overrides
-    });
+    };
 };
 
 export const aUser = (overrides?: Partial<User>): User => {
     return {
-        id: 'b5756f00-51a6-422a-9a7d-c13ee6a63750',
+        id: 'a5756f00-41a6-422a-8a7d-d13ee6a63750',
         login: 'libero',
         avatar: anAvatar(),
         ...overrides
-    });
+    };
 };
 "
 `;
@@ -27,19 +27,19 @@ import { Avatar, User } from './types/graphql';
 
 export const anAvatar = (overrides?: Partial<Avatar>): Avatar => {
     return {
-        id: '1550ff93-cd31-49b4-bc38-ef1cb68bdc38',
+        id: '0550ff93-dd31-49b4-8c38-ff1cb68bdc38',
         url: 'aliquid',
         ...overrides
-    });
+    };
 };
 
 export const aUser = (overrides?: Partial<User>): User => {
     return {
-        id: 'b5756f00-51a6-422a-9a7d-c13ee6a63750',
+        id: 'a5756f00-41a6-422a-8a7d-d13ee6a63750',
         login: 'libero',
         avatar: anAvatar(),
         ...overrides
-    });
+    };
 };
 "
 `;