refactor(config): show warning message for sourceMap: false (#2557)

src/config/config-set.spec.ts

@@ -103,7 +103,7 @@ describe('parsedTsConfig', () => {
       allowSyntheticDefaultImports: true,
       esModuleInterop: false,
     })
-    expect(target.lines.warn.join()).toMatchInlineSnapshot(`
+    expect(target.lines.warn.last).toMatchInlineSnapshot(`
       "[level:40] message TS151001: If you have issues related to imports, you should consider setting \`esModuleInterop\` to \`true\` in your TypeScript configuration file (usually \`tsconfig.json\`). See https://blogs.msdn.microsoft.com/typescript/2018/01/31/announcing-typescript-2-7/#easier-ecmascript-module-interoperability for more information.
       "
     `)

src/config/config-set.ts

@@ -452,6 +452,13 @@ export class ConfigSet {
 
     // parse json, merge config extending others, ...
     const result = ts.parseJsonConfigFileContent(config, ts.sys, basePath, undefined, configFileName)
+    if (result.options.sourceMap === false) {
+      this.logger.warn(
+        interpolate(Deprecations.SourceMapFalseNote, {
+          path: result.options.configFilePath,
+        }),
+      )
+    }
     const { _overriddenCompilerOptions: forcedOptions } = this
     const finalOptions = result.options
     // Target ES5 output by default (instead of ES3).

src/utils/messages.ts

@@ -42,6 +42,7 @@ export const enum Deprecations {
   TsConfig = 'The option `tsConfig` is deprecated and will be removed in ts-jest 27, use `tsconfig` instead',
   PackageJson = 'The option `packageJson` is deprecated and will be removed in ts-jest 27. This option is not used by internal `ts-jest`',
   PathRegex = 'The option `pathRegex` is deprecated and will be removed in ts-jest 27, use `exclude` instead',
+  SourceMapFalseNote = 'Got `sourceMap: false` from tsconfig file "{{path}}". This will disable source map support in ts-jest 27. Please set `sourceMap: true` in your tsconfig file "{{path}}" if you want to keep source map support on',
 }
 
 /**