feat: add "silent" option to cli (#351)

packages/cli/src/__snapshots__/index.test.js.snap

@@ -330,6 +330,8 @@ export default SvgFile
 "
 `;
 
+exports[`cli should suppress output when transforming a directory with a --silent option 1`] = `""`;
+
 exports[`cli should transform a whole directory and output relative destination paths 1`] = `
 "
 __fixtures__/cased/PascalCase.svg -> __fixtures_build__/whole/cased/PascalCase.js

packages/cli/src/dirCommand.js

@@ -2,7 +2,7 @@
 import path from 'path'
 import outputFileSync from 'output-file-sync'
 import readdir from 'recursive-readdir'
-import { convertFile, stat, transformFilename, CASE } from './util'
+import { convertFile, stat, transformFilename, CASE, politeWrite } from './util'
 
 function rename(relative, ext, filenameCase) {
   const relativePath = path.parse(relative)
@@ -32,7 +32,7 @@ async function dirCommand(
     const dest = path.resolve(program.outDir, relative)
     const code = await convertFile(src, options)
     outputFileSync(dest, code)
-    process.stdout.write(`${src} -> ${path.relative(process.cwd(), dest)}\n`)
+    politeWrite(program, `${src} -> ${path.relative(process.cwd(), dest)}\n`)
     return true
   }
 

packages/cli/src/index.js

@@ -80,6 +80,7 @@ program
     parseConfig('--svgo-config'),
   )
   .option('--no-svgo', 'disable SVGO')
+  .option('--silent', 'suppress output')
 
 program.on('--help', () => {
   console.log(`

packages/cli/src/index.test.js

@@ -57,6 +57,15 @@ describe('cli', () => {
     expect(sorted).toMatchSnapshot()
   }, 10000)
 
+  it('should suppress output when transforming a directory with a --silent option', async () => {
+    const result = await cli('--silent --out-dir __fixtures_build__/whole __fixtures__')
+    const sorted = result
+      .split(/\n/)
+      .sort()
+      .join('\n')
+    expect(sorted).toMatchSnapshot()
+  }, 10000)
+
   it('should support --prettier-config as json', async () => {
     const result = await cli(
       `--prettier-config '{"tabWidth": 5}' __fixtures__/simple/file.svg`,

packages/cli/src/util.js

@@ -50,3 +50,9 @@ export function exitError(error) {
   console.error(chalk.red(error))
   process.exit(1)
 }
+
+export function politeWrite(program, data) {
+  if (!program.silent) {
+    process.stdout.write(data);
+  }
+}