[#226] Bugfix: EmptyStackException when command line ends in a cluster of boolean options

Closes #226

Author: remkop

RELEASE-NOTES.md

@@ -4,10 +4,11 @@
 
 ## <a name="2.1.0-fixes"></a> Fixed issues
 
-- [#220] Improve tracing for positional parameters (provide detail on current position).
-- [#221] Document workaround for Grapes bug on Groovy versions before 2.4.7.
-- [#222] Register default converter for Object fields for better scripting support.
-- [#219] Command line system property -Dpicocli.trace (without value) throws exception when used with Groovy.
+- [#226] Bugfix: EmptyStackException when command line ends in a cluster of boolean options
+- [#222] Bugfix: Register default converter for Object fields for better scripting support.
+- [#219] Bugfix: Command line system property -Dpicocli.trace (without value) throws exception when used with Groovy.
+- [#220] Enhancement: Improve tracing for positional parameters (provide detail on current position).
+- [#221] Enhancement: Document workaround for Grapes bug on Groovy versions before 2.4.7.
 
 # <a name="2.0.1"></a> Picocli 2.0.1
 

src/main/java/picocli/CommandLine.java

@@ -2166,7 +2166,7 @@ private void processClusteredShortOptions(Collection<Field> required,
                     }
                     int consumed = applyOption(field, Option.class, arity, paramAttachedToOption, args, initialized, argDescription);
                     // only return if cluster (and maybe more) was consumed, otherwise continue do-while loop
-                    if (consumed > 0) {
+                    if (consumed > 0 || args.isEmpty()) {
                         return;
                     }
                     cluster = args.pop();

src/test/java/picocli/CommandLineTest.java

@@ -3122,4 +3122,21 @@ class Top {
         assertEquals("OPT", ((Top) parsed.get(0).getCommand()).option);
         assertEquals("ABC", ((Sub207A) parsed.get(1).getCommand()).x);
     }
+    @Test
+    public void testIssue226EmptyStackWithClusteredOptions() {
+        class Options {
+            @Option(names = "-b")
+            private boolean buffered = false;
+
+            @Option(names = "-o")
+            private boolean overwriteOutput = true;
+
+            @Option(names = "-v")
+            private boolean verbose = false;
+        }
+        Options options = CommandLine.populateCommand(new Options(), "-bov");
+        assertTrue(options.buffered);
+        assertFalse(options.overwriteOutput);
+        assertTrue(options.verbose);
+    }
 }