Mock npm view in tests that spawn ncu in a child process.

Author: raineorshine

src/package-managers/npm.ts

@@ -20,6 +20,7 @@ import { print } from '../lib/logging'
 import * as versionUtil from '../lib/version-util'
 import { GetVersion } from '../types/GetVersion'
 import { Index } from '../types/IndexType'
+import { MockedVersions } from '../types/MockedVersions'
 import { NpmConfig } from '../types/NpmConfig'
 import { NpmOptions } from '../types/NpmOptions'
 import { Options } from '../types/Options'
@@ -270,6 +271,32 @@ export async function packageAuthorChanged(
   return false
 }
 
+/** Creates a function with the same signature as viewMany that always returns the given versions. */
+export const mockViewMany =
+  (mockReturnedVersions: MockedVersions) =>
+  (name: string, fields: string[], currentVersion: Version, options: Options): Promise<Packument> => {
+    const version =
+      typeof mockReturnedVersions === 'function'
+        ? mockReturnedVersions(options)?.[name]
+        : typeof mockReturnedVersions === 'string'
+        ? mockReturnedVersions
+        : mockReturnedVersions[name]
+
+    const packument = {
+      name,
+      engines: { node: '' },
+      time: { [version || '']: new Date().toISOString() },
+      version: version || '',
+      // versions are not needed in nested packument
+      versions: [],
+    }
+
+    return Promise.resolve({
+      ...packument,
+      versions: [packument],
+    })
+  }
+
 /**
  * Returns an object of specified values retrieved by npm view.
  *
@@ -286,6 +313,12 @@ export async function viewMany(
   retried = 0,
   npmConfigLocal?: NpmConfig,
 ): Promise<Packument> {
+  // See: /test/helpers/stubNpmView
+  if (process.env.STUB_NPM_VIEW) {
+    const mockReturnedVersions = JSON.parse(process.env.STUB_NPM_VIEW)
+    return mockViewMany(mockReturnedVersions)(packageName, fields, currentVersion, options)
+  }
+
   if (currentVersion && (!semver.validRange(currentVersion) || versionUtil.isWildCard(currentVersion))) {
     return Promise.resolve({} as Packument)
   }

src/types/MockedVersions.ts

@@ -0,0 +1,5 @@
+import { Index } from './IndexType'
+import { Options } from './Options'
+import { Version } from './Version'
+
+export type MockedVersions = Version | Index<Version> | ((options: Options) => Index<Version> | null)

test/bin.test.ts

@@ -5,6 +5,7 @@ import fs from 'fs/promises'
 import os from 'os'
 import path from 'path'
 import spawn from 'spawn-please'
+import stubNpmView from './helpers/stubNpmView'
 
 chai.should()
 chai.use(chaiAsPromised)
@@ -15,55 +16,79 @@ process.env.NCU_TESTS = 'true'
 const bin = path.join(__dirname, '../build/src/bin/cli.js')
 
 describe('bin', async function () {
-  it('runs from the command line', async () => {
-    await spawn('node', [bin], '{}')
+  it('fetch latest version from registry (not stubbed)', async () => {
+    const output = await spawn(
+      'node',
+      [bin, '--jsonUpgraded', '--stdin'],
+      '{ "dependencies": { "ncu-test-v2": "1.0.0" } }',
+    )
+    const pkgData = JSON.parse(output)
+    pkgData.should.have.property('ncu-test-v2')
   })
 
   it('output only upgraded with --jsonUpgraded', async () => {
-    const output = await spawn('node', [bin, '--jsonUpgraded', '--stdin'], '{ "dependencies": { "express": "1" } }')
-    const pkgData = JSON.parse(output) as Record<string, unknown>
-    pkgData.should.have.property('express')
+    const stub = stubNpmView('99.9.9', { spawn: true })
+    const output = await spawn(
+      'node',
+      [bin, '--jsonUpgraded', '--stdin'],
+      '{ "dependencies": { "ncu-test-v2": "1.0.0" } }',
+    )
+    const pkgData = JSON.parse(output)
+    pkgData.should.have.property('ncu-test-v2')
+    stub.restore()
   })
 
   it('--loglevel verbose', async () => {
+    const stub = stubNpmView('99.9.9', { spawn: true })
     const output = await spawn('node', [bin, '--loglevel', 'verbose'], '{ "dependencies": { "ncu-test-v2": "1.0.0" } }')
     output.should.containIgnoreCase('Initializing')
     output.should.containIgnoreCase('Running in local mode')
     output.should.containIgnoreCase('Finding package file data')
+    stub.restore()
   })
 
   it('--verbose', async () => {
+    const stub = stubNpmView('99.9.9', { spawn: true })
     const output = await spawn('node', [bin, '--verbose'], '{ "dependencies": { "ncu-test-v2": "1.0.0" } }')
     output.should.containIgnoreCase('Initializing')
     output.should.containIgnoreCase('Running in local mode')
     output.should.containIgnoreCase('Finding package file data')
+    stub.restore()
   })
 
   it('accept stdin', async () => {
+    const stub = stubNpmView('99.9.9', { spawn: true })
     const output = await spawn('node', [bin, '--stdin'], '{ "dependencies": { "express": "1" } }')
     output.trim().should.startWith('express')
+    stub.restore()
   })
 
   it('reject out-of-date stdin with errorLevel 2', async () => {
-    return spawn(
+    const stub = stubNpmView('99.9.9', { spawn: true })
+    await spawn(
       'node',
       [bin, '--stdin', '--errorLevel', '2'],
       '{ "dependencies": { "express": "1" } }',
     ).should.eventually.be.rejectedWith('Dependencies not up-to-date')
+    stub.restore()
   })
 
   it('fall back to package.json search when receiving empty content on stdin', async () => {
+    const stub = stubNpmView('99.9.9', { spawn: true })
     const stdout = await spawn('node', [bin, '--stdin'])
     stdout
       .toString()
       .trim()
       .should.match(/^Checking .+package.json/)
+    stub.restore()
   })
 
   it('use package.json in cwd by default', async () => {
+    const stub = stubNpmView('99.9.9', { spawn: true })
     const output = await spawn('node', [bin, '--jsonUpgraded'], { cwd: path.join(__dirname, 'test-data/ncu') })
     const pkgData = JSON.parse(output)
     pkgData.should.have.property('express')
+    stub.restore()
   })
 
   it('throw error if there is no package', async () => {
@@ -82,6 +107,7 @@ describe('bin', async function () {
   })
 
   it('read --packageFile', async () => {
+    const stub = stubNpmView('99.9.9', { spawn: true })
     const tempDir = await fs.mkdtemp(path.join(os.tmpdir(), 'npm-check-updates-'))
     const pkgFile = path.join(tempDir, 'package.json')
     await fs.writeFile(pkgFile, '{ "dependencies": { "express": "1" } }', 'utf-8')
@@ -91,10 +117,12 @@ describe('bin', async function () {
       pkgData.should.have.property('express')
     } finally {
       await fs.rm(tempDir, { recursive: true, force: true })
+      stub.restore()
     }
   })
 
   it('write to --packageFile', async () => {
+    const stub = stubNpmView('99.9.9', { spawn: true })
     const tempDir = await fs.mkdtemp(path.join(os.tmpdir(), 'npm-check-updates-'))
     const pkgFile = path.join(tempDir, 'package.json')
     await fs.writeFile(pkgFile, '{ "dependencies": { "express": "1" } }', 'utf-8')
@@ -106,10 +134,12 @@ describe('bin', async function () {
       upgradedPkg.dependencies.express.should.not.equal('1')
     } finally {
       await fs.rm(tempDir, { recursive: true, force: true })
+      stub.restore()
     }
   })
 
   it('write to --packageFile if errorLevel=2 and upgrades', async () => {
+    const stub = stubNpmView('99.9.9', { spawn: true })
     const tempDir = await fs.mkdtemp(path.join(os.tmpdir(), 'npm-check-updates-'))
     const pkgFile = path.join(tempDir, 'package.json')
     await fs.writeFile(pkgFile, '{ "dependencies": { "express": "1" } }', 'utf-8')
@@ -124,10 +154,12 @@ describe('bin', async function () {
       upgradedPkg.dependencies.express.should.not.equal('1')
     } finally {
       await fs.rm(tempDir, { recursive: true, force: true })
+      stub.restore()
     }
   })
 
   it('write to --packageFile with jsonUpgraded flag', async () => {
+    const stub = stubNpmView('99.9.9', { spawn: true })
     const tempDir = await fs.mkdtemp(path.join(os.tmpdir(), 'npm-check-updates-'))
     const pkgFile = path.join(tempDir, 'package.json')
     await fs.writeFile(pkgFile, '{ "dependencies": { "express": "1" } }', 'utf-8')
@@ -139,10 +171,12 @@ describe('bin', async function () {
       ugradedPkg.dependencies.express.should.not.equal('1')
     } finally {
       await fs.rm(tempDir, { recursive: true, force: true })
+      stub.restore()
     }
   })
 
   it('ignore stdin if --packageFile is specified', async () => {
+    const stub = stubNpmView('99.9.9', { spawn: true })
     const tempDir = await fs.mkdtemp(path.join(os.tmpdir(), 'npm-check-updates-'))
     const pkgFile = path.join(tempDir, 'package.json')
     await fs.writeFile(pkgFile, '{ "dependencies": { "express": "1" } }', 'utf-8')
@@ -154,15 +188,19 @@ describe('bin', async function () {
       upgradedPkg.dependencies.express.should.not.equal('1')
     } finally {
       await fs.rm(tempDir, { recursive: true, force: true })
+      stub.restore()
     }
   })
 
   it('suppress stdout when --silent is provided', async () => {
+    const stub = stubNpmView('99.9.9', { spawn: true })
     const output = await spawn('node', [bin, '--silent'], '{ "dependencies": { "express": "1" } }')
     output.trim().should.equal('')
+    stub.restore()
   })
 
   it('quote arguments with spaces in upgrade hint', async () => {
+    const stub = stubNpmView('99.9.9', { spawn: true })
     const pkgData = {
       dependencies: {
         'ncu-test-v2': '^1.0.0',
@@ -177,7 +215,22 @@ describe('bin', async function () {
       output.should.include('"ncu-test-v2 ncu-test-tag"')
     } finally {
       await fs.rm(tempDir, { recursive: true, force: true })
+      stub.restore()
+    }
+  })
+
+  it('ignore file: and link: protocols', async () => {
+    const stub = stubNpmView('99.9.9', { spawn: true })
+    const { default: stripAnsi } = await import('strip-ansi')
+    const dependencies = {
+      editor: 'file:../editor',
+      event: 'link:../link',
+      workspace: 'workspace:../workspace',
     }
+    const output = await spawn('node', [bin, '--stdin'], JSON.stringify({ dependencies }))
+
+    stripAnsi(output)!.should.not.include('No package versions were returned.')
+    stub.restore()
   })
 })
 
@@ -195,13 +248,15 @@ describe('embedded versions', () => {
   })
 
   it('strip prefix from npm alias in "to" output', async () => {
+    const stub = stubNpmView('99.9.9', { spawn: true })
     // use dynamic import for ESM module
     const { default: stripAnsi } = await import('strip-ansi')
     const dependencies = {
       request: 'npm:ncu-test-v2@1.0.0',
     }
     const output = await spawn('node', [bin, '--stdin'], JSON.stringify({ dependencies }))
-    stripAnsi(output).trim().should.equal('request  npm:ncu-test-v2@1.0.0  →  2.0.0')
+    stripAnsi(output).trim().should.equal('request  npm:ncu-test-v2@1.0.0  →  99.9.9')
+    stub.restore()
   })
 })
 
@@ -252,17 +307,4 @@ describe('option-specific help', () => {
     const output = await spawn('node', [bin, '--help', '--help'])
     output.trim().should.not.include('Usage')
   })
-
-  it('ignore file: and link: protocols', async () => {
-    const { default: stripAnsi } = await import('strip-ansi')
-    const dependencies = {
-      editor: 'file:../editor',
-      event: 'link:../link',
-    }
-    const output = await spawn('node', [bin, '--stdin'], JSON.stringify({ dependencies }))
-
-    stripAnsi(output)!.should.not.include(
-      'No package versions were returned. This is likely a problem with your installed npm',
-    )
-  })
 })

test/helpers/stubNpmView.ts

@@ -1,37 +1,26 @@
 import sinon from 'sinon'
 import * as npmPackageManager from '../../src/package-managers/npm'
-import { Index } from '../../src/types/IndexType'
-import { Options } from '../../src/types/Options'
-import { Version } from '../../src/types/Version'
+import { MockedVersions } from '../../src/types/MockedVersions'
 
-type MockedVersions = Index<Version>
-type MockedVersionsMatcher = (options: Options) => Index<Version> | null
-
-/** Stubs the npmView function from package-managers/npm. Only works when importing ncu directly in tests, not when the binary is spawned. Returns the stub object. Call stub.restore() after assertions to restore the original function. */
-const stubNpmView = (mockReturnedVersions: Version | MockedVersions | MockedVersionsMatcher) =>
-  sinon
-    .stub(npmPackageManager, 'viewManyMemoized')
-    .callsFake((name: string, fields: string[], currentVersion: Version, options: Options) => {
-      const version =
-        typeof mockReturnedVersions === 'function'
-          ? mockReturnedVersions(options)?.[name]
-          : typeof mockReturnedVersions === 'string'
-          ? mockReturnedVersions
-          : mockReturnedVersions[name]
-
-      const packument = {
-        name,
-        engines: { node: '' },
-        time: { [version || '']: new Date().toISOString() },
-        version: version || '',
-        // versions are not needed in nested packument
-        versions: [],
-      }
-
-      return Promise.resolve({
-        ...packument,
-        versions: [packument],
-      })
-    })
+/** Stubs the npmView function from package-managers/npm. Returns the stub object. Call stub.restore() after assertions to restore the original function. Set spawn:true to stub ncu spawned as a child process. */
+const stubNpmView = (mockReturnedVersions: MockedVersions, { spawn }: { spawn?: boolean } = {}) => {
+  // stub child process
+  // the only way to stub functionality in spawned child processes is to pass data through process.env and stub internally
+  if (spawn) {
+    process.env.STUB_NPM_VIEW = JSON.stringify(mockReturnedVersions)
+    return {
+      restore: () => {
+        // eslint-disable-next-line fp/no-delete
+        delete process.env.STUB_NPM_VIEW
+      },
+    }
+  }
+  // stub module
+  else {
+    return sinon
+      .stub(npmPackageManager, 'viewManyMemoized')
+      .callsFake(npmPackageManager.mockViewMany(mockReturnedVersions))
+  }
+}
 
 export default stubNpmView