feat(graphql): interfaces implementing interfaces

.travis.yml

@@ -11,7 +11,10 @@ install:
   - npm install graphql@$GRAPHQL_CHANNEL
 
 script:
-  - npm test
+  - if [ $GRAPHQL_CHANNEL == 'rc' ];
+    then npm test && npm run lint && npm run prettier-check;
+    else npm test;
+  fi
   - npm run coverage
   - coveralls < ./coverage/lcov.info || true # if coveralls doesn't have it covered
 

package.json

@@ -11,7 +11,6 @@
     "compile": "tsc",
     "pretest": "npm run clean && npm run compile",
     "test": "npm run testonly",
-    "posttest": "npm run lint && npm run prettier:check",
     "lint": "eslint --ext .js,.ts src",
     "lint:watch": "esw --watch --cache --ext .js,.ts src",
     "watch": "tsc -w",
@@ -20,9 +19,9 @@
     "coverage": "istanbul cover _mocha -- --reporter dot --full-trace ./dist/test/**.js",
     "postcoverage": "remap-istanbul --input coverage/coverage.json --type lcovonly --output coverage/lcov.info",
     "prepublishOnly": "npm run compile",
-    "prerelease": "npm test",
     "prettier": "prettier --trailing-comma all --single-quote --write src/**/*.ts",
     "prettier:check": "prettier --trailing-comma all --single-quote --check src/**/*.ts",
+    "prerelease": "npm test && npm run lint && npm run prettier:check",
     "release": "npm run releaseonly",
     "releaseonly": "standard-version"
   },
@@ -84,7 +83,7 @@
     "eslint-watch": "^6.0.1",
     "express": "^4.17.1",
     "express-graphql": "^0.9.0",
-    "graphql": "^14.6.0",
+    "graphql": "^15.0.0-rc.2",
     "graphql-subscriptions": "^1.1.0",
     "graphql-type-json": "^0.3.1",
     "graphql-upload": "^9.0.0",

src/generate/extendResolversFromInterfaces.ts

@@ -1,4 +1,9 @@
-import { GraphQLObjectType, GraphQLSchema } from 'graphql';
+import {
+  GraphQLObjectType,
+  GraphQLSchema,
+  versionInfo,
+  GraphQLInterfaceType,
+} from 'graphql';
 
 import { IResolvers } from '../Interfaces';
 
@@ -15,7 +20,10 @@ function extendResolversFromInterfaces(
   typeNames.forEach(typeName => {
     const typeResolvers = resolvers[typeName];
     const type = schema.getType(typeName);
-    if (type instanceof GraphQLObjectType) {
+    if (
+      type instanceof GraphQLObjectType ||
+      (versionInfo.major >= 15 && type instanceof GraphQLInterfaceType)
+    ) {
       const interfaceResolvers = type
         .getInterfaces()
         .map(iFace => resolvers[iFace.name]);

src/stitching/mergeSchemas.ts

@@ -14,6 +14,7 @@ import {
   GraphQLUnionType,
   GraphQLEnumType,
   ASTNode,
+  versionInfo,
 } from 'graphql';
 
 import {
@@ -361,6 +362,14 @@ function merge(
         }),
         {},
       ),
+      interfaces:
+        versionInfo.major >= 15
+          ? candidates.reduce((acc, candidate) => {
+              const interfaces = (candidate.type as GraphQLInterfaceType).toConfig()
+                .interfaces;
+              return interfaces != null ? acc.concat(interfaces) : acc;
+            }, [])
+          : undefined,
     });
   } else if (initialCandidateType instanceof GraphQLUnionType) {
     return new GraphQLUnionType({

src/stitching/typeFromAST.ts

@@ -28,6 +28,7 @@ import {
   DirectiveLocation,
   GraphQLFieldConfig,
   StringValueNode,
+  versionInfo,
 } from 'graphql';
 
 import { createNamedStub } from '../utils/stub';
@@ -87,6 +88,17 @@ function makeInterfaceType(
   return new GraphQLInterfaceType({
     name: node.name.value,
     fields: () => makeFields(node.fields),
+    interfaces:
+      versionInfo.major >= 15
+        ? () =>
+            node.interfaces.map(
+              iface =>
+                createNamedStub(
+                  iface.name.value,
+                  'interface',
+                ) as GraphQLInterfaceType,
+            )
+        : undefined,
     description: getDescription(node, backcompatOptions),
     resolveType: parent => resolveFromParentTypename(parent),
   });

src/test/testingSchemas.ts

@@ -15,6 +15,7 @@ import {
   ExecutionResult,
   Source,
   GraphQLResolveInfo,
+  versionInfo,
 } from 'graphql';
 import { forAwaitEach } from 'iterall';
 
@@ -272,7 +273,15 @@ const propertyRootTypeDefs = `
     foo: String
   }
 
-  type TestImpl2 implements TestInterface {
+  ${
+    versionInfo.major >= 15
+      ? `interface TestNestedInterface implements TestInterface {
+    kind: TestInterfaceKind
+    testString: String
+  }
+  type TestImpl2 implements TestNestedInterface & TestInterface {`
+      : 'type TestImpl2 implements TestInterface'
+  }
     kind: TestInterfaceKind
     testString: String
     bar: String

src/utils/clone.ts

@@ -8,6 +8,7 @@ import {
   GraphQLScalarType,
   GraphQLSchema,
   GraphQLUnionType,
+  versionInfo,
 } from 'graphql';
 
 import { healTypes } from './heal';
@@ -25,7 +26,12 @@ export function cloneType(type: GraphQLNamedType): GraphQLNamedType {
       interfaces: config.interfaces.slice(),
     });
   } else if (type instanceof GraphQLInterfaceType) {
-    return new GraphQLInterfaceType(type.toConfig());
+    const config = type.toConfig();
+    return new GraphQLInterfaceType({
+      ...config,
+      interfaces:
+        versionInfo.major >= 15 ? config.interfaces.slice() : undefined,
+    });
   } else if (type instanceof GraphQLUnionType) {
     const config = type.toConfig();
     return new GraphQLUnionType({

src/utils/heal.ts

@@ -14,6 +14,7 @@ import {
   GraphQLSchema,
   GraphQLInputType,
   GraphQLOutputType,
+  versionInfo,
 } from 'graphql';
 
 import each from './each';
@@ -123,6 +124,9 @@ export function healTypes(
       return;
     } else if (type instanceof GraphQLInterfaceType) {
       healFields(type);
+      if (versionInfo.major >= 15) {
+        healInterfaces(type);
+      }
       return;
     } else if (type instanceof GraphQLUnionType) {
       healUnderlyingTypes(type);
@@ -151,7 +155,7 @@ export function healTypes(
     });
   }
 
-  function healInterfaces(type: GraphQLObjectType) {
+  function healInterfaces(type: GraphQLObjectType | GraphQLInterfaceType) {
     updateEachKey(type.getInterfaces(), iface => {
       const healedType = healType(iface) as GraphQLInterfaceType;
       return healedType;
@@ -209,7 +213,10 @@ function pruneTypes(
 ) {
   const implementedInterfaces = {};
   each(typeMap, namedType => {
-    if (namedType instanceof GraphQLObjectType) {
+    if (
+      namedType instanceof GraphQLObjectType ||
+      (versionInfo.major >= 15 && namedType instanceof GraphQLInterfaceType)
+    ) {
       each(namedType.getInterfaces(), iface => {
         implementedInterfaces[iface.name] = true;
       });