Add log level option (parcel-bundler#1055)

src/Bundler.js

@@ -85,7 +85,7 @@ class Bundler extends EventEmitter {
           ? false
           : typeof options.hmr === 'boolean' ? options.hmr : watch,
       https: options.https || false,
-      logLevel: typeof options.logLevel === 'number' ? options.logLevel : 3,
+      logLevel: isNaN(options.logLevel) ? 3 : options.logLevel,
       mainFile: this.mainFile,
       hmrPort: options.hmrPort || 0,
       rootDir: Path.dirname(this.mainFile),

src/Logger.js

@@ -14,7 +14,9 @@ class Logger {
 
   setOptions(options) {
     this.logLevel =
-      options && typeof options.logLevel === 'number' ? options.logLevel : 3;
+      options && isNaN(options.logLevel) === false
+        ? Number(options.logLevel)
+        : 3;
     this.color =
       options && typeof options.color === 'boolean'
         ? options.color

src/cli.js

@@ -51,6 +51,11 @@ program
     /^(node|browser|electron)$/
   )
   .option('-V, --version', 'output the version number')
+  .option(
+    '--log-level <level>',
+    'set the log level, either "0" (no output), "1" (errors), "2" (warnings + errors) or "3" (all).',
+    /^([0-3])$/
+  )
   .action(bundle);
 
 program
@@ -86,6 +91,11 @@ program
     'set the runtime environment, either "node", "browser" or "electron". defaults to "browser"',
     /^(node|browser|electron)$/
   )
+  .option(
+    '--log-level <level>',
+    'set the log level, either "0" (no output), "1" (errors), "2" (warnings + errors) or "3" (all).',
+    /^([0-3])$/
+  )
   .action(bundle);
 
 program
@@ -115,6 +125,11 @@ program
     '--detailed-report',
     'print a detailed build report after a completed build'
   )
+  .option(
+    '--log-level <level>',
+    'set the log level, either "0" (no output), "1" (errors), "2" (warnings + errors) or "3" (all).',
+    /^([0-3])$/
+  )
   .action(bundle);
 
 program