Fix subfont --help

Tidy up command line parsing
Add basic tests for cli.js

lib/cli.js

@@ -1,6 +1,14 @@
 #!/usr/bin/env node
 
-require('@gustavnikolaj/async-main-wrap')(require('./subfont'))(
-  require('./parseCommandLineOptions')(),
-  console
-);
+const { yargs, help, ...options } = require('./parseCommandLineOptions')();
+
+require('@gustavnikolaj/async-main-wrap')(require('./subfont'), {
+  processError(err) {
+    yargs.showHelp();
+    if (err.constructor === SyntaxError) {
+      // Avoid rendering a stack trace for the wrong usage errors
+      err.customOutput = err.message;
+    }
+    return err;
+  }
+})(options, console);

lib/parseCommandLineOptions.js

@@ -1,22 +1,9 @@
-const yargs = require('yargs');
-
 module.exports = function parseCommandLineOptions(argv) {
-  const {
-    root,
-    canonicalRoot,
-    output,
-    debug,
-    dryRun,
-    silent,
-    inlineFonts,
-    inlineCss,
-    fontDisplay,
-    inPlace,
-    recursive,
-    fallbacks,
-    dynamic,
-    _: inputFiles
-  } = yargs(argv)
+  let yargs = require('yargs');
+  if (argv) {
+    yargs = yargs(argv);
+  }
+  yargs
     .usage(
       'Create optimal font subsets from your actual font usage.\n$0 [options] <htmlFile(s) | url(s)>'
     )
@@ -104,22 +91,13 @@ module.exports = function parseCommandLineOptions(argv) {
       type: 'boolean',
       default: false
     })
-    .wrap(72).argv;
+    .wrap(require('yargs').terminalWidth());
+
+  const { _: inputFiles, ...rest } = yargs.argv;
 
   return {
-    root,
-    canonicalRoot,
-    output,
-    debug,
-    dryRun,
-    silent,
-    inlineFonts,
-    inlineCss,
-    fontDisplay,
-    inPlace,
+    yargs,
     inputFiles,
-    recursive,
-    fallbacks,
-    dynamic
+    ...rest
   };
 };

lib/subfont.js

@@ -36,7 +36,7 @@ module.exports = async function subfont(
 
       if (rootUrl) {
         if (rootUrl.startsWith('file:')) {
-          console.error(`Guessing --root from input files: ${rootUrl}`);
+          console.warn(`Guessing --root from input files: ${rootUrl}`);
         } else {
           rootUrl = urlTools.ensureTrailingSlash(rootUrl);
         }
@@ -46,20 +46,20 @@ module.exports = async function subfont(
     inputUrls = [`${rootUrl}**/*.html`];
     console.warn(`No input files specified, defaulting to ${inputUrls[0]}`);
   } else {
-    throw new Error(
+    throw new SyntaxError(
       "No input files and no --root specified (or it isn't file:), cannot proceed.\n"
     );
   }
 
   if (!inputUrls[0].startsWith('file:') && !outRoot && !dryRun) {
-    throw new Error(
+    throw new SyntaxError(
       '--output has to be specified when using non-file input urls'
     );
   }
 
   if (!inPlace && !outRoot && !dryRun) {
-    throw new Error(
-      'Either --output, --in-place, or --dryrun has to be specified'
+    throw new SyntaxError(
+      'Either --output, --in-place, or --dry-run has to be specified'
     );
   }
 

test/cli.js

@@ -0,0 +1,122 @@
+const pathModule = require('path');
+const expect = require('unexpected').clone();
+
+const childProcess = require('child_process');
+
+function consumeStream(stream) {
+  return new Promise((resolve, reject) => {
+    const buffers = [];
+    stream
+      .on('data', buffer => buffers.push(buffer))
+      .on('end', () => resolve(Buffer.concat(buffers)))
+      .on('error', reject);
+  });
+}
+
+async function run(commandAndArgs, stdin) {
+  if (typeof commandAndArgs !== 'undefined' && !Array.isArray(commandAndArgs)) {
+    commandAndArgs = [commandAndArgs];
+  }
+
+  const proc = childProcess.spawn(commandAndArgs[0], commandAndArgs.slice(1));
+
+  const promises = {
+    exit: new Promise((resolve, reject) => {
+      proc.on('error', reject).on('exit', exitCode => {
+        if (exitCode === 0) {
+          resolve();
+        } else {
+          const err = new Error(`Child process exited with ${exitCode}`);
+          err.exitCode = exitCode;
+          reject(err);
+        }
+      });
+    }),
+    stdin: new Promise((resolve, reject) => {
+      proc.stdin.on('error', reject).on('close', resolve);
+    }),
+    stdout: consumeStream(proc.stdout),
+    stderr: consumeStream(proc.stderr)
+  };
+
+  if (typeof stdin === 'undefined') {
+    proc.stdin.end();
+  } else {
+    proc.stdin.end(stdin);
+  }
+
+  try {
+    await Promise.all(Object.values(promises));
+    return [await promises.stdout, await promises.stderr];
+  } catch (err) {
+    err.stdout = await promises.stdout;
+    err.stderr = await promises.stderr;
+    throw err;
+  }
+}
+
+async function runSubfont(...args) {
+  const proc = childProcess.spawn(
+    pathModule.resolve(__dirname, '..', 'lib', 'cli.js'),
+    args
+  );
+
+  const promises = {
+    exit: new Promise((resolve, reject) => {
+      proc.on('error', reject).on('exit', exitCode => {
+        if (exitCode === 0) {
+          resolve();
+        } else {
+          const err = new Error(`Child process exited with ${exitCode}`);
+          err.exitCode = exitCode;
+          reject(err);
+        }
+      });
+    }),
+    stdin: new Promise((resolve, reject) => {
+      proc.stdin.on('error', reject).on('close', resolve);
+    }),
+    stdout: consumeStream(proc.stdout),
+    stderr: consumeStream(proc.stderr)
+  };
+
+  proc.stdin.end();
+
+  let err;
+  try {
+    await Promise.all(Object.values(promises));
+  } catch (_err) {
+    err = _err;
+  }
+  return {
+    err,
+    stdout: (await promises.stdout).toString('utf-8'),
+    stderr: (await promises.stderr).toString('utf-8')
+  };
+}
+
+describe('cli', function() {
+  it('should display usage info if --help is passed', async function() {
+    const { err, stdout } = await runSubfont('--help');
+    expect(err, 'to be falsy');
+    expect(stdout, 'to contain', 'Options:');
+    expect(stdout, 'not to contain', 'No input files');
+  });
+
+  it('should display usage info if an error is encountered', async function() {
+    const { err, stderr } = await runSubfont('i-do-not-exist.html');
+    expect(err, 'to have property', 'exitCode', 1);
+    expect(stderr, 'to contain', 'Options:');
+  });
+
+  it('should a wrong usage error without a stack trace', async function() {
+    const { err, stderr } = await runSubfont('https://example.com');
+    expect(err, 'to have property', 'exitCode', 1);
+    expect(
+      stderr,
+      'to contain',
+      '--output has to be specified when using non-file input urls'
+    );
+    expect(stderr, 'not to match', /^\s+at/m);
+  });
+});

test/parseCommandLineOptions.js

@@ -10,7 +10,7 @@ describe('parseCommandLineOptions', function() {
         '--no-fallbacks',
         '--recursive'
       ]),
-      'to equal',
+      'to satisfy',
       {
         root: undefined,
         canonicalRoot: undefined,