Implement a parser for dates

In order to parse user specified strings containing date and time info
a thread-safe parser is implemented. This is needed for example to
interpret configuration parameters (e.g. gc.pruneexpire where need to
parse strings like "2 weeks ago"). The parser is thread-safe by caching
SimpleDateFormat instances in a ThreadLocal cache.

Native git has a parser called approxidate which is able to interpret a
huge number of formats ("1 year ago", "tea time", ...). Ideally JGit
should be able to parse the same strings as native git but for now this
parser understands the following subset:

"now"
"yesterday"
"(x) years|months|weeks|days|hours|minutes|seconds ago"
"yyyy-MM-dd HH:mm:ss Z" (ISO)
"EEE, dd MMM yyyy HH:mm:ss Z" (RFC)
"yyyy-MM-dd"
"yyyy.MM.dd"
"MM/dd/yyyy"
"dd.MM.yyyy"
"EEE MMM dd HH:mm:ss yyyy Z" (DEFAULT)
"EEE MMM dd HH:mm:ss yyyy" (LOCAL)

Change-Id: Iccb66dadb60da13104e73140e53d5e2de068369c

1 files changed, 228 insertions, 0 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/GitDateParserTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/GitDateParserTest.java
new file mode 100644
index 0000000000..11e2e513c6
--- /dev/null
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/GitDateParserTest.java
@@ -0,0 +1,228 @@
+/*
+ * Copyright (C) 2012, Christian Halstrick
+ * and other copyright owners as documented in the project's IP log.
+ *
+ * This program and the accompanying materials are made available
+ * under the terms of the Eclipse Distribution License v1.0 which
+ * accompanies this distribution, is reproduced below, and is
+ * available at http://www.eclipse.org/org/documents/edl-v10.php
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials provided
+ *   with the distribution.
+ *
+ * - Neither the name of the Eclipse Foundation, Inc. nor the
+ *   names of its contributors may be used to endorse or promote
+ *   products derived from this software without specific prior
+ *   written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package org.eclipse.jgit.util;
+
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+import java.util.Calendar;
+import java.util.Date;
+import java.util.GregorianCalendar;
+
+import org.eclipse.jgit.junit.MockSystemReader;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+public class GitDateParserTest {
+	@Before
+	public void setUp() {
+		MockSystemReader mockSystemReader = new MockSystemReader();
+		SystemReader.setInstance(mockSystemReader);
+	}
+
+	@Test
+	public void badlyFormatted() {
+		Calendar ref = new GregorianCalendar(SystemReader.getInstance()
+				.getTimeZone(), SystemReader.getInstance().getLocale());
+		Assert.assertNull(GitDateParser.parse("foo", ref));
+		Assert.assertNull(GitDateParser.parse("", ref));
+		Assert.assertNull(GitDateParser.parse("", null));
+		Assert.assertNull(GitDateParser.parse("1970", ref));
+		Assert.assertNull(GitDateParser.parse("3000.3000.3000", ref));
+		Assert.assertNull(GitDateParser.parse("3 yesterday ago", ref));
+		Assert.assertNull(GitDateParser.parse("now yesterday ago", ref));
+		Assert.assertNull(GitDateParser.parse("yesterdays", ref));
+		Assert.assertNull(GitDateParser.parse("3.day. 2.week.ago", ref));
+		Assert.assertNull(GitDateParser.parse("day ago", ref));
+		Assert.assertNull(GitDateParser.parse("Gra Feb 21 15:35:00 2007 +0100",
+				null));
+		Assert.assertNull(GitDateParser.parse("Sun Feb 21 15:35:00 2007 +0100",
+				null));
+		Assert.assertNull(GitDateParser.parse(
+				"Wed Feb 21 15:35:00 Grand +0100",
+				null));
+	}
+
+	@Test
+	public void yesterday() {
+		GregorianCalendar cal = new GregorianCalendar(SystemReader
+				.getInstance().getTimeZone(), SystemReader.getInstance()
+				.getLocale());
+		Date parse = GitDateParser.parse("yesterday", cal);
+		cal.add(Calendar.DATE, -1);
+		cal.set(Calendar.HOUR_OF_DAY, 0);
+		cal.set(Calendar.MINUTE, 0);
+		cal.set(Calendar.SECOND, 0);
+		cal.set(Calendar.MILLISECOND, 0);
+		cal.set(Calendar.MILLISECOND, 0);
+		Assert.assertEquals(cal.getTime(), parse);
+	}
+
+	@Test
+	public void now() throws ParseException {
+		String dateStr = "2007-02-21 15:35:00 +0100";
+		Date refDate = SystemReader.getInstance()
+				.getSimpleDateFormat("yyyy-MM-dd HH:mm:ss Z").parse(dateStr);
+
+		GregorianCalendar cal = new GregorianCalendar(SystemReader
+				.getInstance().getTimeZone(), SystemReader.getInstance()
+				.getLocale());
+		cal.setTime(refDate);
+
+		Date parse = GitDateParser.parse("now", cal);
+		Assert.assertEquals(refDate, parse);
+		long t1 = SystemReader.getInstance().getCurrentTime();
+		parse = GitDateParser.parse("now", null);
+		long t2 = SystemReader.getInstance().getCurrentTime();
+		Assert.assertTrue(t2 >= parse.getTime() && parse.getTime() >= t1);
+	}
+
+	@Test
+	public void weeksAgo() throws ParseException {
+		String dateStr = "2007-02-21 15:35:00 +0100";
+		SimpleDateFormat df = SystemReader.getInstance()
+				.getSimpleDateFormat("yyyy-MM-dd HH:mm:ss Z");
+		Date refDate = df.parse(dateStr);
+		GregorianCalendar cal = new GregorianCalendar(SystemReader
+				.getInstance().getTimeZone(), SystemReader.getInstance()
+				.getLocale());
+		cal.setTime(refDate);
+
+		Date parse = GitDateParser.parse("2 weeks ago", cal);
+		Assert.assertEquals(df.parse("2007-02-07 15:35:00 +0100"), parse);
+	}
+
+	@Test
+	public void daysAndWeeksAgo() throws ParseException {
+		String dateStr = "2007-02-21 15:35:00 +0100";
+		SimpleDateFormat df = SystemReader.getInstance().getSimpleDateFormat(
+				"yyyy-MM-dd HH:mm:ss Z");
+		Date refDate = df.parse(dateStr);
+		GregorianCalendar cal = new GregorianCalendar(SystemReader
+				.getInstance().getTimeZone(), SystemReader.getInstance()
+				.getLocale());
+		cal.setTime(refDate);
+
+		Date parse = GitDateParser.parse("2 weeks ago", cal);
+		Assert.assertEquals(df.parse("2007-02-07 15:35:00 +0100"), parse);
+		parse = GitDateParser.parse("3 days 2 weeks ago", cal);
+		Assert.assertEquals(df.parse("2007-02-04 15:35:00 +0100"), parse);
+		parse = GitDateParser.parse("3.day.2.week.ago", cal);
+		Assert.assertEquals(df.parse("2007-02-04 15:35:00 +0100"), parse);
+	}
+
+	@Test
+	public void iso() throws ParseException {
+		String dateStr = "2007-02-21 15:35:00 +0100";
+		Date exp = SystemReader.getInstance()
+				.getSimpleDateFormat("yyyy-MM-dd HH:mm:ss Z").parse(dateStr);
+		Date parse = GitDateParser.parse(dateStr, null);
+		Assert.assertEquals(exp, parse);
+	}
+
+	@Test
+	public void rfc() throws ParseException {
+		String dateStr = "Wed, 21 Feb 2007 15:35:00 +0100";
+		Date exp = SystemReader.getInstance()
+				.getSimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss Z")
+				.parse(dateStr);
+		Date parse = GitDateParser.parse(dateStr, null);
+		Assert.assertEquals(exp, parse);
+	}
+
+	@Test
+	public void shortFmt() throws ParseException {
+		String dateStr = "2007-02-21";
+		Date exp = SystemReader.getInstance().getSimpleDateFormat("yyyy-MM-dd")
+				.parse(dateStr);
+		Date parse = GitDateParser.parse(dateStr, null);
+		Assert.assertEquals(exp, parse);
+	}
+
+	@Test
+	public void shortWithDots() throws ParseException {
+		String dateStr = "2007.02.21";
+		Date exp = SystemReader.getInstance().getSimpleDateFormat("yyyy.MM.dd")
+				.parse(dateStr);
+		Date parse = GitDateParser.parse(dateStr, null);
+		Assert.assertEquals(exp, parse);
+	}
+
+	@Test
+	public void shortWithSlash() throws ParseException {
+		String dateStr = "02/21/2007";
+		Date exp = SystemReader.getInstance().getSimpleDateFormat("MM/dd/yyyy")
+				.parse(dateStr);
+		Date parse = GitDateParser.parse(dateStr, null);
+		Assert.assertEquals(exp, parse);
+	}
+
+	@Test
+	public void shortWithDotsReverse() throws ParseException {
+		String dateStr = "21.02.2007";
+		Date exp = SystemReader.getInstance().getSimpleDateFormat("dd.MM.yyyy")
+				.parse(dateStr);
+		Date parse = GitDateParser.parse(dateStr, null);
+		Assert.assertEquals(exp, parse);
+	}
+
+	@Test
+	public void defaultFmt() throws ParseException {
+		String dateStr = "Wed Feb 21 15:35:00 2007 +0100";
+		Date exp = SystemReader.getInstance()
+				.getSimpleDateFormat("EEE MMM dd HH:mm:ss yyyy Z")
+				.parse(dateStr);
+		Date parse = GitDateParser.parse(dateStr, null);
+		Assert.assertEquals(exp, parse);
+	}
+
+	@Test
+	public void local() throws ParseException {
+		String dateStr = "Wed Feb 21 15:35:00 2007";
+		Date exp = SystemReader.getInstance()
+				.getSimpleDateFormat("EEE MMM dd HH:mm:ss yyyy").parse(dateStr);
+		Date parse = GitDateParser.parse(dateStr, null);
+		Assert.assertEquals(exp, parse);
+	}
+}