ErrorProne: Enable and fix UnusedException check

Enable UnusedException at ERROR level which causes the build to fail
in many places with:

  [UnusedException] This catch block catches an symbol and re-throws
  another, but swallows the caught symbol rather than setting it as a
  cause. This can make debugging harder.

Fix it by setting the caught exception as cause on the subsequently
thrown exception.

Note: The grammatically incorrect error message is copy-pasted as-is
from the version of ErrorProne currently used in Bazel; it has been
fixed by [1] in the latest version.

[1] https://github.com/google/error-prone/commit/d57a39c

Change-Id: I11ed38243091fc12f64f1b2db404ba3f1d2e98b5
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

1 files changed, 6 insertions, 2 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/io/TimeoutOutputStreamTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/io/TimeoutOutputStreamTest.java
index 024f0f3b00..567880f478 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/io/TimeoutOutputStreamTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/io/TimeoutOutputStreamTest.java
@@ -149,7 +149,9 @@ public class TimeoutOutputStreamTest {
 					try {
 						Thread.sleep(1000);
 					} catch (InterruptedException e) {
-						throw new InterruptedIOException();
+						InterruptedIOException e1 = new InterruptedIOException();
+						e1.initCause(e);
+						throw e1;
 					}
 				}
 			}
@@ -202,7 +204,9 @@ public class TimeoutOutputStreamTest {
 					try {
 						Thread.sleep(1000);
 					} catch (InterruptedException e) {
-						throw new InterruptedIOException();
+						InterruptedIOException e1 = new InterruptedIOException();
+						e1.initCause(e);
+						throw e1;
 					}
 				}
 			}