From fc2c4076a7c14b9eee27fa6bfa18d1b410785a69 Mon Sep 17 00:00:00 2001
From: Peter Palaga <ppalaga@redhat.com>
Date: Mon, 21 Dec 2020 16:07:00 +0100
Subject: [PATCH] Support short variants of boolean properties #279

---
 .../org/mvndaemon/mvnd/client/DaemonParameters.java    |  3 ++-
 .../org/mvndaemon/mvnd/client/EnvironmentTest.java     | 10 ++++++++++
 .../java/org/mvndaemon/mvnd/common/OptionType.java     |  5 ++++-
 3 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/client/src/main/java/org/mvndaemon/mvnd/client/DaemonParameters.java b/client/src/main/java/org/mvndaemon/mvnd/client/DaemonParameters.java
index 5945825e..c09c0423 100644
--- a/client/src/main/java/org/mvndaemon/mvnd/client/DaemonParameters.java
+++ b/client/src/main/java/org/mvndaemon/mvnd/client/DaemonParameters.java
@@ -596,7 +596,8 @@ public class DaemonParameters {
         }
 
         public boolean asBoolean() {
-            return Boolean.parseBoolean(get());
+            final String val = get();
+            return "".equals(val) || Boolean.parseBoolean(val);
         }
 
         public int asInt() {
diff --git a/client/src/test/java/org/mvndaemon/mvnd/client/EnvironmentTest.java b/client/src/test/java/org/mvndaemon/mvnd/client/EnvironmentTest.java
index f7a6427c..5dca9740 100644
--- a/client/src/test/java/org/mvndaemon/mvnd/client/EnvironmentTest.java
+++ b/client/src/test/java/org/mvndaemon/mvnd/client/EnvironmentTest.java
@@ -24,6 +24,8 @@ import java.util.Map;
 import java.util.Properties;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
+import org.mvndaemon.mvnd.client.DaemonParameters.EnvValue;
+import org.mvndaemon.mvnd.client.DaemonParameters.ValueSource;
 import org.mvndaemon.mvnd.common.Environment;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
@@ -119,6 +121,14 @@ public class EnvironmentTest {
         assertEquals("C:\\jdk-11.0.2\\", Environment.cygpath("/cygdrive/c/jdk-11.0.2/"));
     }
 
+    @Test
+    void emptyBooleanEnvValueIsTrue() {
+        final String EMPTY_STRING = "";
+        final EnvValue envVal = new EnvValue(Environment.MVND_NO_BUFERING,
+                new ValueSource(sb -> sb.append("envValueAsBoolean"), () -> EMPTY_STRING));
+        assertEquals(true, envVal.asBoolean());
+    }
+
     static class EnvironmentResource implements AutoCloseable {
 
         private final Properties props = new Properties();
diff --git a/common/src/main/java/org/mvndaemon/mvnd/common/OptionType.java b/common/src/main/java/org/mvndaemon/mvnd/common/OptionType.java
index 082eda17..cbf49ec3 100644
--- a/common/src/main/java/org/mvndaemon/mvnd/common/OptionType.java
+++ b/common/src/main/java/org/mvndaemon/mvnd/common/OptionType.java
@@ -23,7 +23,10 @@ import java.util.stream.Stream;
 import org.mvndaemon.mvnd.common.Environment.DocumentedEnumEntry;
 
 public enum OptionType {
-    /** <code>true</code> or <code>false</code> */
+    /**
+     * <code>true</code> or <code>false</code>; empty string is also interpreted as <code>true</code> - so
+     * <code>-Dmvnd.noBuffering</code> is equivalent to <code>-Dmvnd.noBuffering=true</code>
+     */
     BOOLEAN,
     /**
      * An unlabeled whole number of milliseconds or a whole number followed by an optional space and a unit