fix: check package resolution of @graphql-codegen/typescript-resolver…

…s before passing it to codegen api (#516)

README.md

@@ -472,22 +472,6 @@ TSConfigFile: tsconfig.compile.json
 # for `gql()` and `load()` calls.
 typeInjectEntrypoint: node_modules/@types/graphql-let/index.d.ts
 
-# "schemaEntrypoint", optional. You need this only if you want to use Resolver Types.
-# Since you could point to multiple schemas, this path is
-# used to generate `.d.ts` to generate `*.graphqls.d.ts`. If you do this,
-#
-#   schema: **/*.graphqls
-#   schemaEntrypoint: schema.graphqls
-#
-# you can import the generated resolver types like below.
-#
-#   import { Resolvers } from '../schema.graphqls'
-#
-# It doesn't matter if the file of the path exists. I recommend
-# you to specify a normal relative path without glob symbols (`**`) like this.
-schemaEntrypoint: schema.graphqls
-schemaEntrypoint: lib/schema.graphqls
-
 # "silent", optional. `false` by default.
 # Pass `true` if you want to suppress all standard output from graphql-let.
 silent: false
@@ -598,26 +582,22 @@ schema. Just use what you need; it's most likely to be `jest-transform-graphql`.
 
 If you meet the following conditions, graphql-let generates Resolver Types.
 
--   You have `schemaEntrypoint` in the config
 -   You have file paths including glob patterns in `schema`
 -   You have
     [`@graphql-codegen/typescript-resolvers`](https://graphql-code-generator.com/docs/plugins/typescript-resolvers)
     installed
--   your `schemaEntrypoint` in .graphql-let.yml points to a single local GraphQL
-    schema file (`.graphqls`)
 
 Run:
 
 ```bash
 yarn add -D @graphql-codegen/typescript-resolvers
-
 yarn graphql-let
 ```
 
-Then you will get `${schemaEntrypoint}.d.ts`. Import the types from it.
+Then you will get resolver types in `graphql-let/__generated__/__types__`.
 
 ```typescript
-import { Resolvers } from "../schema.graphqls";
+import { Resolvers } from "graphql-let/__generated__/__types__";
 
 const resolvers: Resolvers = {
   Query: {
@@ -631,9 +611,8 @@ const resolvers: Resolvers = {
 export default resolvers;
 ```
 
-`graphql-let/schema/loader` is also available. It generates/updates
-`graphql-let/__generated__/__types__.d.ts` but it doesn't transpile anything;
-just passes the file content to the next webpack loader.
+`graphql-let/schema/loader` is also available to update resolver types. It doesn't transpile anything;
+just detects file modification and passes the content to the next loader.
 
 ```diff
   // webpack.config.ts

src/lib/codegen.ts

@@ -14,10 +14,11 @@ import { CodegenContext, getSchemaImportContext, isAllSkip } from './types';
 import ConfiguredOutput = Types.ConfiguredOutput;
 
 const OPTIONAL_SCHEMA_PLUGINS = ['typescript-resolvers'];
-function findOptionalSchemaPlugins() {
+function getOptionalSchemaPlugins() {
   const plugins: string[] = [];
   for (const c of OPTIONAL_SCHEMA_PLUGINS) {
     try {
+      require(`@graphql-codegen/${c}`);
       plugins.push(c);
       // eslint-disable-next-line no-empty
     } catch (e) {}
@@ -31,7 +32,7 @@ function findOptionalSchemaPlugins() {
 // cases where you need to configure this more. Issue it then.
 function getFixedSchemaConfig() {
   return {
-    plugins: ['typescript', ...findOptionalSchemaPlugins()],
+    plugins: ['typescript', ...getOptionalSchemaPlugins()],
   };
 }
 

src/lib/dts.ts

@@ -179,7 +179,7 @@ export function genDts(
 
   if (tsxFullPaths.length !== dtsContents.length) {
     throw new Error(
-      `Never supposed to be here. Please make an issue on GitHub.`,
+      `Never. Requested .tsx length and result .d.ts length are not matched.`,
     );
   }
 

src/lib/hash.ts

@@ -4,7 +4,7 @@ import { EOL } from 'os';
 
 const shouldCareNewline = EOL !== '\n';
 const RegexCRLF = /\r\n/g;
-const leadingStringOfGeneratedContent = '/* ';
+const leadingLettersForFileHash = '/* ';
 const hexHashLength = 40;
 
 function normalizeNewline(input: string | Buffer): string {
@@ -24,7 +24,7 @@ export function createHashFromBuffers(ss: (string | Buffer)[]): string {
 }
 
 export function withHash(sourceHash: string, content: string): string {
-  return `${leadingStringOfGeneratedContent}${sourceHash}
+  return `${leadingLettersForFileHash}${sourceHash}
  * This file is automatically generated by graphql-let. */
 
 ${content}`;
@@ -36,8 +36,8 @@ export function readHash(filePath: string): string | null {
     // https://gist.github.com/piglovesyou/537a8157ba691e8e9e023263bfc7838d
     const content = readFileSync(filePath, 'utf-8');
     const hash = content.slice(
-      leadingStringOfGeneratedContent.length,
-      leadingStringOfGeneratedContent.length + hexHashLength,
+      leadingLettersForFileHash.length,
+      leadingLettersForFileHash.length + hexHashLength,
     );
     if (hash) return hash;
     return null;