Added simultaneous support of jest v26 & v27 for transformer (#548)

* Added simultaneous support of jest v26 & v27 for transformer

* Fixed compat with require of non-default-exported members

* Slight adjustments of codestyle and arguments rename

* Backmerged with master to work against yarn v3 + Jest types should be definitely bumped to v27

* Backmerged master and resolved lock file issues

Co-authored-by: Vadym Okun <[email protected]>

package.json

@@ -64,8 +64,8 @@
     "@graphql-codegen/typescript-resolvers": "1.19.1",
     "@graphql-tools/graphql-file-loader": "6.2.7",
     "@graphql-tools/import": "6.3.1",
-    "@jest/transform": "26.6.2",
-    "@jest/types": "26.6.2",
+    "@jest/transform": "^27.1.0",
+    "@jest/types": "^27.1.0",
     "@types/babel-plugin-macros": "2.8.5",
     "@types/babel__core": "7.1.15",
     "@types/babel__preset-env": "7.9.2",
@@ -76,7 +76,7 @@
     "@types/diff": "5.0.1",
     "@types/eslint": "7.2.8",
     "@types/eslint-plugin-prettier": "3.1.0",
-    "@types/jest": "26.0.24",
+    "@types/jest": "^27.0.1",
     "@types/loader-utils": "2.0.3",
     "@types/lodash.pick": "4.4.6",
     "@types/memory-fs": "0.3.3",
@@ -94,7 +94,7 @@
     "@typescript-eslint/eslint-plugin": "4.26.0",
     "@typescript-eslint/parser": "4.28.3",
     "@typescript/vfs": "1.3.4",
-    "babel-jest": "26.6.3",
+    "babel-jest": "^27.1.0",
     "babel-loader": "8.2.2",
     "babel-plugin-macros": "3.1.0",
     "babel-plugin-module-resolver": "4.1.0",
@@ -110,7 +110,7 @@
     "graphql": "14.7.0",
     "graphql-tag": "2.12.5",
     "husky": "6.0.0",
-    "jest": "26.6.3",
+    "jest": "^27.1.0",
     "lint-staged": "10.5.4",
     "lodash.pick": "4.4.0",
     "memory-fs": "0.5.0",
@@ -124,7 +124,7 @@
     "remark-toc": "7.2.0",
     "rimraf": "3.0.2",
     "terminate": "2.1.2",
-    "ts-jest": "26.5.6",
+    "ts-jest": "^27.0.5",
     "tslib": "2.3.1",
     "typescript": "4.2.3",
     "wait-on": "5.3.0",

src/jestTransformer.test.ts

@@ -5,12 +5,12 @@ import compiler from './lib/__tools/compile';
 import { prepareFixtures } from './lib/__tools/file';
 
 let cwd: string;
-let jestConfig: Config.ProjectConfig;
+let config: Partial<Config.ProjectConfig>;
 
 describe('graphql-let/jestTransformer', () => {
   beforeAll(async () => {
     [cwd] = await prepareFixtures(__dirname, '__fixtures/jestTransformer');
-    jestConfig = { rootDir: cwd } as Config.ProjectConfig;
+    config = { rootDir: cwd };
   });
 
   test('transforms .graphql', async () => {
@@ -22,10 +22,12 @@ describe('graphql-let/jestTransformer', () => {
       .filter(Boolean);
 
     const fullPath = join(cwd, fileName);
+    // @ts-expect-error
     const { code: transformedContent } = jestTransformer.process(
       fileData!,
       fullPath,
-      jestConfig,
+      // @ts-expect-error
+      { config },
     ) as { code: string };
     expect(removeSourcemapReference(transformedContent)).toMatchSnapshot();
   });

src/jestTransformer.ts

@@ -12,6 +12,13 @@ type JestTransformerOptions = {
   subsequentTransformer?: string;
 };
 
+function getDefaultExportIfExists(moduleName: string) {
+  // eslint-disable-next-line @typescript-eslint/no-var-requires
+  const mod = require(moduleName);
+
+  return (mod?.default || mod) as typeof mod;
+}
+
 function getOption(jestConfig: ProjectConfig): JestTransformerOptions {
   if (!Array.isArray(jestConfig.transform)) return {};
   for (const [, entryPoint, opts] of jestConfig.transform) {
@@ -20,40 +27,40 @@ function getOption(jestConfig: ProjectConfig): JestTransformerOptions {
   return {};
 }
 
-const jestTransformer: Transformer = {
-  getCacheKey(fileData, filename, configString) {
-    return createHash(fileData + filename + configString + 'graphql-let');
+const jestTransformer: Transformer<JestTransformerOptions> = {
+  getCacheKey(sourceText, sourcePath, options) {
+    const configString = options?.configString || options;
+
+    return createHash(sourceText + sourcePath + configString + 'graphql-let');
   },
-  process(input, filePath, jestConfig, transformOptions) {
+  process(sourceText, sourcePath, ...rest) {
+    // jest v26 vs v27 changes to support both formats: start
+    const [__compatJestConfig] = rest;
+    const jestConfig = __compatJestConfig?.config ?? __compatJestConfig;
+    // jest v26 vs v27 changes to support both formats: end
     const { rootDir: cwd } = jestConfig;
     const { configFile, subsequentTransformer } = getOption(jestConfig);
     const [config, configHash] = loadConfigSync(cwd, configFile);
     const { execContext } = createExecContextSync(cwd, config, configHash);
 
-    const { tsxFullPath } = createPaths(execContext, relative(cwd, filePath));
+    const { tsxFullPath } = createPaths(execContext, relative(cwd, sourcePath));
     const tsxContent = readFileSync(tsxFullPath, 'utf-8');
 
     // Let users customize a subsequent transformer
     if (subsequentTransformer) {
-      // eslint-disable-next-line @typescript-eslint/no-var-requires
-      return require(subsequentTransformer).process(
-        tsxContent,
-        tsxFullPath,
-        jestConfig,
-        transformOptions,
+      const _subsequentTransformer = getDefaultExportIfExists(
+        subsequentTransformer,
       );
+      return _subsequentTransformer.process(tsxContent, tsxFullPath, ...rest);
     }
 
+    // jest v26 vs v27 changes to support both formats: start
     // "babel-jest" by default
     // eslint-disable-next-line @typescript-eslint/no-var-requires
-    const { createTransformer } = require('babel-jest');
+    const { createTransformer } = getDefaultExportIfExists('babel-jest');
+    // jest v26 vs v27 changes to support both formats: end
     const babelTransformer = createTransformer({ cwd: cwd });
-    return babelTransformer.process(
-      tsxContent,
-      tsxFullPath,
-      jestConfig,
-      transformOptions,
-    );
+    return babelTransformer.process(tsxContent, tsxFullPath, ...rest);
   },
 };