improve: remove @nexus/schema & graphql from peer deps (#735)

Co-authored-by: Jason Kuhrt <jasonkuhrt@me.com>

package.json

@@ -22,26 +22,22 @@
     "release:stable": "dripip stable",
     "release:pr": "dripip pr",
     "clean": "rm -rf dist",
-    "build": "ts-node scripts/ensure-prisma2-version && yarn -s clean && yarn -s build:module-facades && tsc && ts-node scripts/post-build",
+    "build": "yarn clean && yarn build:module-facades && tsc && ts-node scripts/post-build",
     "build:module-facades": "node scripts/build-module-facades",
     "build:ci": "tsc",
     "dev": "yarn -s build:module-facades && tsc --watch",
     "prepublishOnly": "yarn -s build",
     "format": "prettier --write 'src/**/*.ts' 'tests/**/*.ts' 'examples/**/*.ts'",
     "postinstall": "node ./scripts/postinstall.js",
-    "test": "ts-node scripts/ensure-prisma2-version && ts-node tests/__ensure-engine && jest --forceExit",
-    "test:dev": "ts-node scripts/ensure-prisma2-version && ts-node tests/__ensure-engine && jest src tests/schema --watch",
+    "test": "ts-node tests/__ensure-engine && jest --forceExit",
+    "test:dev": "ts-node tests/__ensure-engine && jest src tests/schema --watch",
     "test:unit": "jest src --testTimeout=15000 --forceExit",
     "test:schema": "yarn test --testTimeout=15000 tests/schema",
     "test:fw:e2e:mysql": "yarn test --testTimeout=400000 tests/framework/e2e/mysql.test.ts",
     "test:fw:e2e:postgres": "yarn test --testTimeout=400000 tests/framework/e2e/postgres.test.ts",
     "test:fw:e2e:sqlite": "yarn test --testTimeout=400000 tests/framework/e2e/sqlite.test.ts",
     "test:db:setup": "docker-compose down && rm -rf .mysql-data && rm -rf .postgres-data && docker-compose up -d"
   },
-  "peerDependencies": {
-    "@nexus/schema": "^0.14.0",
-    "graphql": "^14.6.0"
-  },
   "dependencies": {
     "@prisma/cli": "2.1.3",
     "@prisma/client": "2.1.3",

src/schema-entrypoint.ts

@@ -1 +1,6 @@
+import { ensureDepIsInstalled } from './schema/utils'
+
+ensureDepIsInstalled('@nexus/schema')
+ensureDepIsInstalled('graphql')
+
 export * from './schema'

src/schema/utils.ts

@@ -3,6 +3,7 @@ import * as fs from 'fs-extra'
 import { GraphQLResolveInfo } from 'graphql'
 import * as path from 'path'
 import { isDeepStrictEqual } from 'util'
+import chalk from 'chalk'
 
 /**
  * Write file contents but first delete the file off disk if present. This is a
@@ -185,3 +186,22 @@ export const isEmptyObject = (o: any) => isDeepStrictEqual(o, {})
 export function keys<A extends object>(a: A): (keyof A)[] {
   return Object.keys(a) as any
 }
+
+export function ensureDepIsInstalled(depName: string) {
+  try {
+    require(depName)
+  } catch (err) {
+    if (err.code === 'MODULE_NOT_FOUND') {
+      console.error(
+        `${chalk.redBright('ERROR:')} When nexus-plugin-prisma is used as a Nexus Schema plugin, ${chalk.greenBright(
+          depName
+        )} must be installed as a dependency. Please run \`${chalk.greenBright(
+          `npm install ${depName}`
+        )}\`.`
+      )
+      process.exit(1)
+    } else {
+      throw err
+    }
+  }
+}