feat: show help for unrecognized commands (#308)

packages/cli/package.json

@@ -47,6 +47,7 @@
     "chalk": "^2.3.0",
     "cli-table": "^0.3.1",
     "commander": "^2.17.1",
+    "fuzzaldrin": "^2.1.0",
     "date-fns": "^1.29.0",
     "glob": "^7.1.2",
     "inquirer": "^6.2.0",

packages/cli/src/api/__snapshots__/utils.test.js.snap

@@ -0,0 +1,11 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`helpMisspelledCommand - show help for misspelled commands should return command is invalid if no commands are configured 1`] = `lingui: command compile is not a lingui command. See 'lingui --help' for the list of available commands.`;
+
+exports[`helpMisspelledCommand - show help for misspelled commands should return suggestions for mispelled 1`] = `
+lingui: command compilesss is not a lingui command. See 'lingui --help' for the list of available commands.
+
+Did you mean: compile?
+`;
+
+exports[`helpMisspelledCommand - show help for misspelled commands shouldn't output anything if user passes no command 1`] = `undefined`;

packages/cli/src/api/utils.js

@@ -1,6 +1,7 @@
 import fs from "fs"
 import path from "path"
 import chalk from "chalk"
+import { score } from "fuzzaldrin"
 
 export function removeDirectory(dir, keep = false) {
   if (!fs.existsSync(dir)) return
@@ -33,6 +34,43 @@ export function prettyOrigin(origins) {
   }
 }
 
+/**
+ * .. js:function:: helpMisspelledCommand(command [, availableCommands = []])
+ *    :param: command - command passed to CLI
+ *    :param: availableCommands - all commands defined in commander.js
+ *
+ *    If unknown commands is passed to CLI, check it agains all available commands
+ *    for possible misspelled letter. Output help with suggestions to console.
+ */
+export function helpMisspelledCommand(command, availableCommands = []) {
+  const commandNames = availableCommands.map(command => command.name())
+
+  // if no command is supplied, then commander.js shows help automatically
+  if (!command || commandNames.includes(command)) {
+    return
+  }
+
+  const suggestions = commandNames
+    .map(name => ({
+      name,
+      score: score(name, command.slice(0, name.length))
+    }))
+    .filter(nameScore => nameScore.score > 0)
+    .slice(0, 3)
+    .map(commandScore => chalk.inverse(commandScore.name))
+    .join(", ")
+
+  console.log(
+    `lingui: command ${command} is not a lingui command. ` +
+      `See 'lingui --help' for the list of available commands.`
+  )
+
+  if (suggestions) {
+    console.log()
+    console.log(`Did you mean: ${suggestions}?`)
+  }
+}
+
 export const splitOrigin = origin => origin.split(":")
 
 export const joinOrigin = origin => origin.join(":")

packages/cli/src/api/utils.test.js

@@ -0,0 +1,44 @@
+import { helpMisspelledCommand } from "./utils"
+import { mockConsole } from "../mocks"
+
+function getConsoleMockCalls({ mock }) {
+  if (!mock.calls.length) return
+  return mock.calls.map(call => call[0]).join("\n")
+}
+
+describe("helpMisspelledCommand - show help for misspelled commands", function() {
+  function mockCommands(command, commandNames) {
+    return helpMisspelledCommand(
+      command,
+      commandNames.map(commandName => ({ name: () => commandName }))
+    )
+  }
+
+  it("shouldn't output anything if command is valid", function() {
+    mockConsole(console => {
+      mockCommands("compile", ["compile"])
+      expect(getConsoleMockCalls(console.log)).toBeUndefined()
+    })
+  })
+
+  it("shouldn't output anything if user passes no command", function() {
+    mockConsole(console => {
+      mockCommands("", ["compile"])
+      expect(getConsoleMockCalls(console.log)).toMatchSnapshot()
+    })
+  })
+
+  it("should return command is invalid if no commands are configured", function() {
+    mockConsole(console => {
+      mockCommands("compile", [])
+      expect(getConsoleMockCalls(console.log)).toMatchSnapshot()
+    })
+  })
+
+  it("should return suggestions for mispelled", function() {
+    mockConsole(console => {
+      mockCommands("compilesss", ["compile"])
+      expect(getConsoleMockCalls(console.log)).toMatchSnapshot()
+    })
+  })
+})

packages/cli/src/lingui.js

@@ -1,5 +1,7 @@
 #!/usr/bin/env node
 
+import { helpMisspelledCommand } from "./api/utils"
+
 const program = require("commander")
 
 let version
@@ -19,3 +21,5 @@ program
   .command("extract [files...]", "Extracts messages from source files")
   .command("compile", "Compile message catalogs")
   .parse(process.argv)
+
+helpMisspelledCommand(process.argv[2], program.commands)

yarn.lock

@@ -2717,6 +2717,10 @@ functional-red-black-tree@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/functional-red-black-tree/-/functional-red-black-tree-1.0.1.tgz#1b0ab3bd553b2a0d6399d29c0e3ea0b252078327"
 
+fuzzaldrin@^2.1.0:
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/fuzzaldrin/-/fuzzaldrin-2.1.0.tgz#90204c3e2fdaa6941bb28d16645d418063a90e9b"
+
 gauge@~2.7.3:
   version "2.7.4"
   resolved "https://registry.yarnpkg.com/gauge/-/gauge-2.7.4.tgz#2c03405c7538c39d7eb37b317022e325fb018bf7"