Add --noop option

This option causes the IDE to process its commandline arguments and then
quit. This allows setting preferences uses --pref, without having to
also load the GUI or compile a sketch.

Author: matthijskooijman

app/src/processing/app/Base.java

@@ -268,7 +268,7 @@ static protected void initRequirements() {
   }
 
 
-  protected static enum ACTION { GUI, VERIFY, UPLOAD };
+  protected static enum ACTION { GUI, VERIFY, UPLOAD, NOOP };
   public Base(String[] args) throws Exception {
     platform.init(this);
 
@@ -331,6 +331,7 @@ public Base(String[] args) throws Exception {
     final Map<String, ACTION> actions = new HashMap<String, ACTION>();
     actions.put("--verify", ACTION.VERIFY);
     actions.put("--upload", ACTION.UPLOAD);
+    actions.put("--noop", ACTION.NOOP);
 
     // Check if any files were passed in on the command line
     for (int i = 0; i < args.length; i++) {
@@ -405,6 +406,9 @@ public Base(String[] args) throws Exception {
     if ((action == ACTION.UPLOAD || action == ACTION.VERIFY) && filenames.size() != 1)
       showError(null, _("Must specify exactly one sketch file"), 3);
 
+    if (action == ACTION.NOOP && filenames.size() != 0)
+      showError(null, _("Cannot specify any sketch files"), 3);
+
     if ((action != ACTION.UPLOAD && action != ACTION.VERIFY) && (doVerboseBuild || doVerboseUpload))
       showError(null, _("--verbose, --verbose-upload and --verbose-build can only be used together with --verify or --upload"), 3);
 
@@ -485,6 +489,10 @@ public Base(String[] args) throws Exception {
           new UpdateCheck(this);
         }
         break;
+      case NOOP:
+        // Do nothing (intended for only changing preferences)
+        System.exit(0);
+        break;
     }
   }
 

build/shared/manpage.adoc

@@ -145,6 +145,10 @@ OPTIONS
 *--verify*::
 	Build the sketch.
 
+*--noop*::
+	Immediately quit after processing the commandline. This can be
+	used to just set preferences with *--pref*.
+
 PREFERENCES
 -----------
 Arduino keeps a list of preferences, as simple name and value pairs.
@@ -232,6 +236,10 @@ re-use any previous build results in that directory.
 
      arduino --pref build.path=/path/to/sketch/build --verify /path/to/sketch/sketch.ino
 
+Change the selected board and build path and do nothing else.
+
+     arduino --pref build.path=/path/to/sketch/build --board arduino:avr:uno --noop
+
 HISTORY
 -------
 1.5.2::
@@ -259,7 +267,7 @@ HISTORY
 	Windows, the splash screen is still shown.
 
 1.5.7::
-	Introduced *--no-save-prefs*.
+	Introduced *--no-save-prefs* and *--noop*.
 
 {empty}::
 	*--board* and *--port* options are now saved to the preferences