Used package install command for list of required ESLint-related packages

.eslintrc.js

@@ -18,6 +18,7 @@ module.exports = {
     },
     plugins: ["@typescript-eslint"],
     rules: {
+        "@typescript-eslint/require-array-sort-compare": "off",
         "@typescript-eslint/consistent-type-definitions": ["error", "type"],
         "@typescript-eslint/explicit-function-return-type": "off",
         "@typescript-eslint/explicit-module-boundary-types": "off",
@@ -36,6 +37,7 @@ module.exports = {
         "@typescript-eslint/no-unsafe-member-access": "off",
         "@typescript-eslint/no-unsafe-return": "off",
         "@typescript-eslint/no-untyped-public-signature": "off",
+        "@typescript-eslint/no-unused-vars": "off",
         "@typescript-eslint/no-use-before-define": "off",
         "@typescript-eslint/prefer-readonly-parameter-types": "off",
         "@typescript-eslint/prefer-reduce-type-parameter": "off",

src/cli/main.ts

@@ -43,8 +43,11 @@ import { findTSLintConfiguration } from "../input/findTSLintConfiguration";
 import { findTypeScriptConfiguration } from "../input/findTypeScriptConfiguration";
 import { importer, ImporterDependencies } from "../input/importer";
 import { mergeLintConfigurations } from "../input/mergeLintConfigurations";
-import { ReportConversionResultsDependencies } from "../reporting/dependencies";
-import { reportConversionResults } from "../reporting/reportConversionResults";
+import { choosePackageManager } from "../reporting/packages/choosePackageManager";
+import {
+    reportConversionResults,
+    ReportConversionResultsDependencies,
+} from "../reporting/reportConversionResults";
 import { reportEditorSettingConversionResults } from "../reporting/reportEditorSettingConversionResults";
 import { convertRules, ConvertRulesDependencies } from "../rules/convertRules";
 import { mergers } from "../rules/mergers";
@@ -86,7 +89,12 @@ const findOriginalConfigurationsDependencies: FindOriginalConfigurationsDependen
     mergeLintConfigurations,
 };
 
+const choosePackageManagerDependencies = {
+    fileSystem: fsFileSystem,
+};
+
 const reportConversionResultsDependencies: ReportConversionResultsDependencies = {
+    choosePackageManager: bind(choosePackageManager, choosePackageManagerDependencies),
     logger: processLogger,
 };
 

src/conversion/convertConfig.ts

@@ -57,7 +57,7 @@ export const convertConfig = async (
     }
 
     // 5. A summary of the results is printed to the user's console
-    dependencies.reportConversionResults(simplifiedConfiguration);
+    await dependencies.reportConversionResults(simplifiedConfiguration);
 
     return {
         status: ResultStatus.Succeeded,

src/reporting/packages/choosePackageManager.test.ts

@@ -0,0 +1,30 @@
+import { choosePackageManager } from "./choosePackageManager";
+import { PackageManager } from "./packageManagers";
+
+describe("choosePackageManager", () => {
+    it("uses a non-npm package manager when that package manager's lock file exists", async () => {
+        // Arrange
+        const fileSystem = {
+            fileExists: async (fileName: string) => fileName === "./yarn.lock",
+        };
+
+        // Act
+        const result = await choosePackageManager({ fileSystem });
+
+        // Assert
+        expect(result).toEqual(PackageManager.Yarn);
+    });
+
+    it("uses npm when no lock file exists", async () => {
+        // Arrange
+        const fileSystem = {
+            fileExists: async () => false,
+        };
+
+        // Act
+        const result = await choosePackageManager({ fileSystem });
+
+        // Assert
+        expect(result).toEqual(PackageManager.npm);
+    });
+});

src/reporting/packages/choosePackageManager.ts

@@ -0,0 +1,16 @@
+import { FileSystem } from "../../adapters/fileSystem";
+import { preferredLockfiles, PackageManager } from "./packageManagers";
+
+export type ChoosePackageManagerDependencies = {
+    fileSystem: Pick<FileSystem, "fileExists">;
+};
+
+export const choosePackageManager = async (dependencies: ChoosePackageManagerDependencies) => {
+    for (const [packageManager, lockFile] of preferredLockfiles) {
+        if (await dependencies.fileSystem.fileExists(lockFile)) {
+            return packageManager;
+        }
+    }
+
+    return PackageManager.npm;
+};

src/reporting/packages/packageManagers.ts

@@ -0,0 +1,17 @@
+export enum PackageManager {
+    npm,
+    pnpm,
+    Yarn,
+}
+
+export const preferredLockfiles = new Map([
+    [PackageManager.npm, "./package-lock.json"],
+    [PackageManager.pnpm, "./pnpm-lock.yaml"],
+    [PackageManager.Yarn, "./yarn.lock"],
+]);
+
+export const installationMessages = {
+    [PackageManager.npm]: (packages: string) => `npm install ${packages} --save-dev`,
+    [PackageManager.pnpm]: (packages: string) => `pnpm add ${packages} --save-dev`,
+    [PackageManager.Yarn]: (packages: string) => `yarn add ${packages} --dev`,
+};

src/reporting/reportConversionResults.test.ts

@@ -3,10 +3,18 @@ import { EOL } from "os";
 import { createStubLogger, expectEqualWrites } from "../adapters/logger.stubs";
 import { createEmptyConversionResults } from "../conversion/conversionResults.stubs";
 import { ESLintRuleOptions } from "../rules/types";
+import { PackageManager } from "./packages/packageManagers";
 import { reportConversionResults } from "./reportConversionResults";
 
+const createStubDependencies = (packageManager = PackageManager.Yarn) => {
+    const choosePackageManager = jest.fn().mockResolvedValueOnce(packageManager);
+    const logger = createStubLogger();
+
+    return { choosePackageManager, logger };
+};
+
 describe("reportConversionResults", () => {
-    it("logs a successful conversion without notices when there is one converted rule without notices", () => {
+    it("logs a successful conversion without notices when there is one converted rule without notices", async () => {
         // Arrange
         const conversionResults = createEmptyConversionResults({
             converted: new Map<string, ESLintRuleOptions>([
@@ -21,19 +29,22 @@ describe("reportConversionResults", () => {
             ]),
         });
 
-        const logger = createStubLogger();
+        const { choosePackageManager, logger } = createStubDependencies();
 
         // Act
-        reportConversionResults({ logger }, conversionResults);
+        await reportConversionResults({ choosePackageManager, logger }, conversionResults);
 
         // Assert
         expectEqualWrites(
             logger.stdout.write,
-            `✨ 1 rule replaced with its ESLint equivalent. ✨${EOL}`,
+            `✨ 1 rule replaced with its ESLint equivalent. ✨`,
+            ``,
+            `⚡ 3 packages are required for running with ESLint. ⚡`,
+            `  yarn add @typescript-eslint/eslint-plugin @typescript-eslint/parser eslint --dev`,
         );
     });
 
-    it("logs a successful conversion with notices when there is one converted rule with notices", () => {
+    it("logs a successful conversion with notices when there is one converted rule with notices", async () => {
         // Arrange
         const conversionResults = createEmptyConversionResults({
             converted: new Map<string, ESLintRuleOptions>([
@@ -49,10 +60,10 @@ describe("reportConversionResults", () => {
             ]),
         });
 
-        const logger = createStubLogger();
+        const { choosePackageManager, logger } = createStubDependencies();
 
         // Act
-        reportConversionResults({ logger }, conversionResults);
+        await reportConversionResults({ choosePackageManager, logger }, conversionResults);
 
         // Assert
         expectEqualWrites(
@@ -62,10 +73,13 @@ describe("reportConversionResults", () => {
             `  * tslint-rule-one:`,
             `    - 1`,
             `    - 2`,
+            ``,
+            `⚡ 3 packages are required for running with ESLint. ⚡`,
+            `  yarn add @typescript-eslint/eslint-plugin @typescript-eslint/parser eslint --dev`,
         );
     });
 
-    it("logs successful conversions when there are multiple converted rules", () => {
+    it("logs successful conversions when there are multiple converted rules", async () => {
         // Arrange
         const conversionResults = createEmptyConversionResults({
             converted: new Map<string, ESLintRuleOptions>([
@@ -90,35 +104,39 @@ describe("reportConversionResults", () => {
             ]),
         });
 
-        const logger = createStubLogger();
+        const { choosePackageManager, logger } = createStubDependencies();
 
         // Act
-        reportConversionResults({ logger }, conversionResults);
+        await reportConversionResults({ choosePackageManager, logger }, conversionResults);
 
         // Assert
         expectEqualWrites(
             logger.stdout.write,
-            `✨ 2 rules replaced with their ESLint equivalents. ✨${EOL}`,
+            `✨ 2 rules replaced with their ESLint equivalents. ✨`,
+            ``,
             `❗ 2 ESLint rules behave differently from their TSLint counterparts ❗`,
             `  * tslint-rule-one:`,
             `    - 1`,
             `    - 2`,
             `  * tslint-rule-two:`,
             `    - 3`,
             `    - 4`,
+            ``,
+            `⚡ 3 packages are required for running with ESLint. ⚡`,
+            `  yarn add @typescript-eslint/eslint-plugin @typescript-eslint/parser eslint --dev`,
         );
     });
 
-    it("logs a failed conversion when there is one failed conversion", () => {
+    it("logs a failed conversion when there is one failed conversion", async () => {
         // Arrange
         const conversionResults = createEmptyConversionResults({
             failed: [{ getSummary: () => "It broke." }],
         });
 
-        const logger = createStubLogger();
+        const { choosePackageManager, logger } = createStubDependencies();
 
         // Act
-        reportConversionResults({ logger }, conversionResults);
+        await reportConversionResults({ choosePackageManager, logger }, conversionResults);
 
         // Assert
         expectEqualWrites(
@@ -128,16 +146,16 @@ describe("reportConversionResults", () => {
         );
     });
 
-    it("logs failed conversions when there are multiple failed conversions", () => {
+    it("logs failed conversions when there are multiple failed conversions", async () => {
         // Arrange
         const conversionResults = createEmptyConversionResults({
             failed: [{ getSummary: () => "It broke." }, { getSummary: () => "It really broke." }],
         });
 
-        const logger = createStubLogger();
+        const { choosePackageManager, logger } = createStubDependencies();
 
         // Act
-        reportConversionResults({ logger }, conversionResults);
+        await reportConversionResults({ choosePackageManager, logger }, conversionResults);
 
         // Assert
         expectEqualWrites(
@@ -147,7 +165,7 @@ describe("reportConversionResults", () => {
         );
     });
 
-    it("logs a missing rule when there is a missing rule", () => {
+    it("logs a missing rule when there is a missing rule", async () => {
         // Arrange
         const conversionResults = createEmptyConversionResults({
             missing: [
@@ -159,24 +177,27 @@ describe("reportConversionResults", () => {
             ],
         });
 
-        const logger = createStubLogger();
+        const { choosePackageManager, logger } = createStubDependencies();
 
         // Act
-        reportConversionResults({ logger }, conversionResults);
+        await reportConversionResults({ choosePackageManager, logger }, conversionResults);
 
         // Assert
         expectEqualWrites(
             logger.stdout.write,
             "❓ 1 rule does not yet have an ESLint equivalent ❓",
             `  See generated log file; defaulting to eslint-plugin-tslint for it.`,
+            "",
+            "⚡ 3 packages are required for running with ESLint. ⚡",
+            "  yarn add @typescript-eslint/eslint-plugin @typescript-eslint/parser eslint --dev",
         );
         expectEqualWrites(
             logger.info.write,
             'tslint-to-eslint-config does not know the ESLint equivalent for TSLint\'s "tslint-rule-one"',
         );
     });
 
-    it("logs missing rules when there are missing rules", () => {
+    it("logs missing rules when there are missing rules", async () => {
         // Arrange
         const conversionResults = createEmptyConversionResults({
             missing: [
@@ -193,16 +214,19 @@ describe("reportConversionResults", () => {
             ],
         });
 
-        const logger = createStubLogger();
+        const { choosePackageManager, logger } = createStubDependencies();
 
         // Act
-        reportConversionResults({ logger }, conversionResults);
+        await reportConversionResults({ choosePackageManager, logger }, conversionResults);
 
         // Assert
         expectEqualWrites(
             logger.stdout.write,
             "❓ 2 rules do not yet have ESLint equivalents ❓",
             `  See generated log file; defaulting to eslint-plugin-tslint for these rules.`,
+            "",
+            "⚡ 3 packages are required for running with ESLint. ⚡",
+            "  yarn add @typescript-eslint/eslint-plugin @typescript-eslint/parser eslint --dev",
         );
         expectEqualWrites(
             logger.info.write,
@@ -211,42 +235,22 @@ describe("reportConversionResults", () => {
         );
     });
 
-    it("logs a missing plugin when there is a missing plugin", () => {
-        // Arrange
-        const conversionResults = createEmptyConversionResults({
-            plugins: new Set(["plugin-one"]),
-        });
-
-        const logger = createStubLogger();
-
-        // Act
-        reportConversionResults({ logger }, conversionResults);
-
-        // Assert
-        expectEqualWrites(
-            logger.stdout.write,
-            "⚡ 1 package is required for new ESLint rules. ⚡",
-            "  plugin-one",
-        );
-    });
-
-    it("logs missing plugins when there are missing plugins", () => {
+    it("logs missing plugins when there are missing plugins", async () => {
         // Arrange
         const conversionResults = createEmptyConversionResults({
             plugins: new Set(["plugin-one", "plugin-two"]),
         });
 
-        const logger = createStubLogger();
+        const { choosePackageManager, logger } = createStubDependencies();
 
         // Act
-        reportConversionResults({ logger }, conversionResults);
+        await reportConversionResults({ choosePackageManager, logger }, conversionResults);
 
         // Assert
         expectEqualWrites(
             logger.stdout.write,
-            "⚡ 2 packages are required for new ESLint rules. ⚡",
-            "  plugin-one",
-            "  plugin-two",
+            "⚡ 5 packages are required for running with ESLint. ⚡",
+            "  yarn add @typescript-eslint/eslint-plugin @typescript-eslint/parser eslint plugin-one plugin-two --dev",
         );
     });
 });