add warning from issue yarnpkg#2495

src/cli/commands/global.js

@@ -178,7 +178,11 @@ const {run, setFlags: _setFlags} = buildSubCommands('global', {
     await updateCwd(config);
 
     const updateBins = await initUpdateBins(config, reporter, flags);
-
+
+    if (args.includes('yarn')) {
+      reporter.warn(reporter.lang('packageContainsYarnAsGlobal'));
+
+    }
     // install module
     const lockfile = await Lockfile.fromDirectory(config.cwd);
     const install = new GlobalAdd(args, flags, config, reporter, lockfile);

src/reporters/lang/en.js

@@ -1,5 +1,5 @@
 /* @flow */
- /* eslint max-len: 0 */
+/* eslint max-len: 0 */
 
 const messages = {
   upToDate: 'Already up-to-date.',
@@ -20,7 +20,7 @@ const messages = {
   offlineRetrying: 'There appears to be trouble with your network connection. Retrying...',
   clearedCache: 'Cleared cache.',
   packWroteTarball: 'Wrote tarball to $0.',
-
+  
   manifestPotentialTypo: 'Potential typo $0, did you mean $1?',
   manifestBuiltinModule: '$0 is also the name of a node core module',
   manifestNameDot: "Name can't start with a dot",
@@ -31,23 +31,23 @@ const messages = {
   manifestStringExpected: '$0 is not a string',
   manifestDependencyCollision: '$0 has dependency $1 with range $2 that collides with a dependency in $3 of the same name with version $4',
   manifestDirectoryNotFound: 'Unable to read $0 directory of module $1',
-
+  
   verboseFileCopy: 'Copying $0 to $1.',
   verboseFileSymlink: 'Creating symlink at $0 to $1.',
   verboseFileSkip: 'Skipping copying of file $0 as the file at $1 is the same size ($2) and mtime ($3).',
   verboseFileSkipSymlink: 'Skipping copying of $0 as the file at $1 is the same symlink ($2).',
   verboseFileRemoveExtraneous: 'Removing extraneous file $0.',
   verboseFilePhantomExtraneous: "File $0 would be marked as extraneous but has been removed as it's listed as a phantom file.",
   verboseFileFolder: 'Creating directory $0.',
-
+  
   verboseRequestStart: 'Performing $0 request to $1.',
   verboseRequestFinish: 'Request $0 finished with status code $1.',
-
+  
   configSet: 'Set $0 to $1.',
   configDelete: 'Deleted $0.',
   configNpm: 'npm config',
   configYarn: 'yarn config',
-
+  
   couldntFindPackagejson: "Couldn't find a package.json file in $0",
   couldntFindMatch: "Couldn't find match for $0 in $1 for $2.",
   couldntFindPackageInCache: "Couldn't find any versions for $0 that matches $1 in our cache. Possible versions: $2",
@@ -91,15 +91,15 @@ const messages = {
   allDependenciesUpToDate: 'All of your dependencies are up to date.',
   frozenLockfileError: 'Your lockfile needs to be updated, but yarn was run with `--frozen-lockfile`.',
   fileWriteError: 'Could not write file $0: $1',
-
+  
   yarnOutdated: "Your current version of Yarn is out of date. The latest version is $0 while you're on $1.",
   yarnOutdatedInstaller: 'To upgrade, download the latest installer at $0.',
   yarnOutdatedCommand: 'To upgrade, run the following command:',
-
+  
   tooManyArguments: 'Too many arguments, maximum of $0.',
   tooFewArguments: 'Not enough arguments, expected at least $0.',
   noArguments: "This command doesn't require any arguments.",
-
+  
   ownerRemoving: 'Removing owner $0 from package $1.',
   ownerRemoved: 'Owner removed.',
   ownerRemoveError: "Couldn't remove owner.",
@@ -110,73 +110,73 @@ const messages = {
   ownerAdding: 'Adding owner $0 to package $1',
   ownerAddingFailed: "Couldn't add owner.",
   ownerNone: 'No owners.',
-
+  
   teamCreating: 'Creating team',
   teamRemoving: 'Removing team',
   teamAddingUser: 'Adding user to team',
   teamRemovingUser: 'Removing user from team',
   teamListing: 'Listing teams',
-
+  
   cleaning: 'Cleaning modules',
   cleanCreatingFile: 'Creating $0',
-
+  
   binLinkCollision: "There's already a linked binary called $0 in your global Yarn bin. Could not link this package's $0 bin entry.",
   linkCollision: "There's already a module called $0 registered.",
   linkMissing: 'No registered module found called $0.',
   linkInstallMessage: 'You can now run `yarn link $0` in the projects where you want to use this module and it will be used instead.',
   linkRegistered: 'Registered $0.',
   linkUnregistered: 'Unregistered $0.',
   linkUsing: 'Using linked module for $0.',
-
+  
   commandNotSpecified: 'No command specified.',
   binCommands: 'Commands available from binary scripts: ',
   possibleCommands: 'Project commands',
   commandQuestion: 'Which command would you like to run?',
   commandFailed: 'Command failed with exit code $0.',
-
+  
   foundIncompatible: 'Found incompatible module',
   incompatibleEngine: 'The engine $0 is incompatible with this module. Expected version $1.',
   incompatibleCPU: 'The CPU architecture $0 is incompatible with this module.',
   incompatibleOS: 'The platform $0 is incompatible with this module.',
   invalidEngine: 'The engine $0 appears to be invalid.',
-
+  
   selfUpdateReleased: 'Replaced current release with $0.',
   selfUpdateDownloading: 'Downloading yarn version $0.',
   selfUpdateNoNewer: 'Yarn is already using the latest version.',
-
+  
   optionalCompatibilityExcluded: '$0 is an optional dependency and failed compatibility check. Excluding it from installation.',
   optionalModuleFail: 'This module is OPTIONAL, you can safely ignore this error',
   optionalModuleScriptFail: 'Error running install script for optional dependency: $0',
   optionalModuleCleanupFail: 'Could not cleanup build artifacts from failed install: $0',
-
+  
   unmetPeer: '$0 has unmet peer dependency $1.',
   incorrectPeer: '$0 has incorrect peer dependency $1.',
-
+  
   savedNewDependency: 'Saved 1 new dependency.',
   savedNewDependencies: 'Saved $0 new dependencies.',
-
+  
   foundWarnings: 'Found $0 warnings.',
   foundErrors: 'Found $0 errors.',
-
+  
   savedLockfile: 'Saved lockfile.',
   noRequiredLockfile: 'No lockfile in this directory. Run `yarn install` to generate one.',
   noLockfileFound: 'No lockfile found.',
-
+  
   invalidSemver: 'Invalid semver version',
   newVersion: 'New version',
   currentVersion: 'Current version',
-
+  
   manualVersionResolution: 'Unable to find a suitable version for $0, please choose one by typing one of the numbers below:',
   manualVersionResolutionOption: '$0 which resolved to $1',
-
+  
   createdTag: 'Created tag.',
   createdTagFail: "Couldn't add tag.",
   deletedTag: 'Deleted tag.',
   deletedTagFail: "Couldn't delete tag.",
   gettingTags: 'Getting tags',
   deletingTags: 'Deleting tag',
   creatingTag: 'Creating tag $0 = $1',
-
+  
   whyStart: 'Why do we have the module $0?',
   whyFinding: 'Finding dependency',
   whyCalculating: 'Calculating file sizes',
@@ -188,46 +188,46 @@ const messages = {
   whyDiskSizeTransitive: 'Disk size with transitive dependencies: $0',
   whySharedDependencies: 'Amount of shared dependencies: $0',
   whyHoistedTo: `Has been hoisted to $0`,
-
+  
   whyHoistedFromSimple: `This module exists because it's hoisted from $0.`,
   whyDependedOnSimple: `This module exists because $0 depends on it.`,
   whySpecifiedSimple: `This module exists because it's specified in $0.`,
   whyReasons: 'Reasons this module exists',
   whyHoistedFrom: 'Hoisted from $0',
   whyDependedOn: '$0 depends on it',
   whySpecified: `Specified in $0`,
-
+  
   uninstalledPackages: 'Uninstalled packages.',
   uninstallRegenerate: 'Regenerating lockfile and installing missing dependencies',
-
+  
   cleanRemovedFiles: 'Removed $0 files',
   cleanSavedSize: 'Saved $0 MB.',
-
+  
   npmUsername: 'npm username',
   npmPassword: 'npm password',
   npmEmail: 'npm email',
-
+  
   loggingIn: 'Logging in',
   loggedIn: 'Logged in.',
   notRevokingEnvToken: 'Not revoking login token, specified via environment variable.',
   notRevokingConfigToken: 'Not revoking login token, specified via config file.',
   noTokenToRevoke: 'No login token to revoke.',
   revokingToken: 'Revoking token',
   revokedToken: 'Revoked login token.',
-
+  
   loginAsPublic: 'Logging in as public',
   incorrectCredentials: 'Incorrect username or password.',
   clearedCredentials: 'Cleared login credentials.',
-
+  
   publishSame: 'New version is the same as the current version.',
   publishFail: "Couldn't publish package.",
   publishPrivate: 'Package marked as private, not publishing.',
   published: 'Published.',
   publishing: 'Publishing',
-
+  
   infoFail: 'Received invalid response from npm.',
   malformedRegistryResponse: 'Received malformed response from registry for $0. The registry may be down.',
-
+  
   cantRequestOffline: 'Can\'t make a request in offline mode',
   requestManagerNotSetupHAR: 'RequestManager was not setup to capture HAR files',
   requestError: 'Request $0 returned a $1',
@@ -238,17 +238,16 @@ const messages = {
   errorDecompressingTarball: '$0. Error decompressing $1, it appears to be corrupt.',
   updateInstalling: 'Installing $0...',
   hostedGitResolveError: 'Error connecting to repository. Please, check the url.',
-
+  
   unknownFetcherFor: 'Unknown fetcher for $0',
-
+  
   refusingDownloadGitWithoutCommit: 'Refusing to download the git repo $0 over plain git without a commit hash',
   refusingDownloadHTTPWithoutCommit: 'Refusing to download the git repo $0 over HTTP without a commit hash',
   refusingDownloadHTTPSWithoutCommit: 'Refusing to download the git repo $0 over HTTPS without a commit hash - possible certificate error?',
-
+  
   packageInstalledWithBinaries: 'Installed $0 with binaries:',
   packageHasBinaries: '$0 has binaries:',
   packageHasNoBinaries: '$0 has no binaries',
-
   couldBeDeduped: '$0 could be deduped from $1 to $2',
   lockfileNotContainPatter: 'Lockfile does not contain pattern: $0',
   integrityHashesDontMatch: 'Integrity hashes don\'t match, expected $0 but got $1',
@@ -257,6 +256,7 @@ const messages = {
   optionalDepNotInstalled: 'Optional dependency $0 not installed',
   packageWrongVersion: '$0 is wrong version: expected $1, got $2',
   packageDontSatisfy: '$0 doesn\'t satisfy found match of $1',
+  packageContainsYarnAsGlobal: 'installing Yarn via Yarn will result in you having two separate versions of Yarn installed at the same time.',
 };
 
 export type LanguageKeys = $Keys<typeof messages>;