Implement most '%' formatting types for os.date()

README.html

@@ -458,7 +458,7 @@ A richer version for use by <em>JsePlatform</em> is :
 	src/jse/org/luaj/vm2/lib/jse/JseOsLib.java
 </pre>
 
-Time is a represented as number of milliseconds since the epoch, 
+Time is a represented as number of seconds since the epoch, 
 and most time and date formatting, locales, and other features 
 are not implemented.
 
@@ -887,6 +887,7 @@ Files are no longer hosted at LuaForge.
 <tr valign="top"><td>&nbsp;&nbsp;<b>3.0-beta2</b></td><td><ul>
 <li>LuaValue.checkfunction() now returns LuaFunction.</li>
 <li>Fix os.time() to return a number of seconds.</li>
+<li>Implement most '%' formatting types for os.date().</li>
 
 </ul></td></tr>
 </table></td></tr></table>
@@ -901,6 +902,6 @@ Files are no longer hosted at LuaForge.
 <li>negative zero is treated as identical to integer value zero throughout luaj
 <li>lua compiled into java bytecode using luajc cannot use string.dump() or xpcall()
 <li>number formatting with string.format() is not supported
-<li>date formatting with os.date() is not supported
+<li>os.time(), and os.date() not completely supported
 </ul>
 

src/core/org/luaj/vm2/lib/OsLib.java

@@ -22,7 +22,11 @@
 package org.luaj.vm2.lib;
 
 import java.io.IOException;
+import java.util.Calendar;
+import java.util.Date;
+import java.util.TimeZone;
 
+import org.luaj.vm2.Buffer;
 import org.luaj.vm2.Globals;
 import org.luaj.vm2.LuaTable;
 import org.luaj.vm2.LuaValue;
@@ -137,7 +141,7 @@ public class OsLib extends TwoArgFunction {
 				case DATE: {
 					String s = args.optjstring(1, null);
 					double t = args.optdouble(2,-1);
-					return valueOf( date(s, t==-1? System.currentTimeMillis()/1000.: t) );
+					return valueOf( date(s, t==-1? time(null): t) );
 				}
 				case DIFFTIME:
 					return valueOf(difftime(args.checkdouble(1),args.checkdouble(2)));
@@ -174,7 +178,8 @@ public class OsLib extends TwoArgFunction {
 
 	/**
 	 * @return an approximation of the amount in seconds of CPU time used by 
-	 * the program.
+	 * the program.  For luaj this simple returns the elapsed time since the 
+	 * OsLib class was loaded.
 	 */
 	protected double clock() {
 		return (System.currentTimeMillis()-t0) / 1000.;
@@ -196,15 +201,9 @@ public class OsLib extends TwoArgFunction {
 	 * (see the os.time function for a description of this value). 
 	 * Otherwise, date formats the current time.
 	 * 
-	 * If format starts with '!', then the date is formatted in Coordinated 
+	 * Date returns the date as a string, 
-	 * Universal Time. After this optional character, if format is the string 
+	 * formatted according to the same rules as ANSII strftime, but without
-	 * "*t", then date returns a table with the following fields: year 
+	 * support for %g, %G, or %V.
-	 * (four digits), month (1--12), day (1--31), hour (0--23), min (0--59), 
-	 * sec (0--61), wday (weekday, Sunday is 1), yday (day of the year), 
-	 * and isdst (daylight saving flag, a boolean).
-	 * 
-	 * If format is not "*t", then date returns the date as a string, 
-	 * formatted according to the same rules as the C function strftime.
 	 * 
 	 * When called without arguments, date returns a reasonable date and 
 	 * time representation that depends on the host system and on the 
@@ -215,10 +214,171 @@ public class OsLib extends TwoArgFunction {
 	 * @return a LString or a LTable containing date and time, 
 	 * formatted according to the given string format.
 	 */
-	protected String date(String format, double time) {
+	public String date(String format, double time) {
-		return new java.util.Date((long)(time*1000)).toString();
+		byte[] fmt = format.getBytes();
+		final int n = fmt.length;
+		Buffer result = new Buffer(n);
+		byte c;
+		Date date = new Date((long)(time*1000));
+		Calendar d = Calendar.getInstance();
+		d.setTime(date);
+		for ( int i = 0; i < n; ) {
+			switch ( c = fmt[i++ ] ) {
+			case '\n':
+				result.append( "\n" );
+				break;
+			default:
+				result.append( c );
+				break;
+			case '%':
+				if (i >= n) break;
+				switch ( c = fmt[i++ ] ) {
+				default:
+					result.append( (byte)'%' );
+					result.append( (byte)c );
+					break;
+				case '%':
+					result.append( (byte)'%' );
+					break;
+				case 'a':
+					result.append(WeekdayNameAbbrev[d.get(Calendar.DAY_OF_WEEK)-1]);
+					break;
+				case 'A':
+					result.append(WeekdayName[d.get(Calendar.DAY_OF_WEEK)-1]);
+					break;
+				case 'b':
+				case 'h':
+					result.append(MonthNameAbbrev[d.get(Calendar.MONTH)]);
+					break;
+				case 'B':
+					result.append(MonthName[d.get(Calendar.MONTH)]);
+					break;					 
+				case 'c': 
+					result.append(date("%a %b %d %H:%M:%S %Y", time));
+					break;
+				case 'C':
+					result.append(String.valueOf((100000+d.get(Calendar.YEAR))/100).substring(2));
+					break;
+				case 'd':
+					result.append(String.valueOf(100+d.get(Calendar.DAY_OF_MONTH)).substring(1));
+					break;
+				case 'e': {
+					final String s = String.valueOf(d.get(Calendar.DAY_OF_MONTH));
+					if (s.length() < 2)
+						result.append((byte)' ');
+					result.append(s);
+					break;
+				}
+				case 'F':
+					result.append(date("%Y-%m-%d", time));
+					break;
+				case 'H':
+					result.append(String.valueOf(100+d.get(Calendar.HOUR_OF_DAY)).substring(1));
+					break;
+				case 'I':
+					result.append(String.valueOf(100+(d.get(Calendar.HOUR_OF_DAY)%12)).substring(1));
+					break;
+				case 'j': { // day of year.
+					Calendar y0 = beginningOfYear(d);
+					int dayOfYear = (int) ((d.getTime().getTime() - y0.getTime().getTime()) / (24 * 3600L * 1000L));
+					result.append(String.valueOf(1001+dayOfYear).substring(1));
+					break;
+				}
+				case 'm':
+					result.append(String.valueOf(101+d.get(Calendar.MONTH)).substring(1));
+					break;
+				case 'M':
+					result.append(String.valueOf(100+d.get(Calendar.MINUTE)).substring(1));
+					break;
+				case 'n':
+					result.append((byte)'\n');
+					break;
+				case 'p':
+					result.append(d.get(Calendar.HOUR_OF_DAY) < 12? "AM": "PM");
+					break;
+				case 'R':
+					result.append(date("%H:%M", time));
+					break;
+				case 'r': {
+					final String s = date("%I:%M:%S", time);
+					result.append(s);
+					result.append(d.get(Calendar.HOUR_OF_DAY) < 12? " am": " pm");
+					break;
+				}
+				case 'S':
+					result.append(String.valueOf(100+d.get(Calendar.SECOND)).substring(1));
+					break;
+				case 't':
+					result.append((byte)'\t');
+					break;
+				case 'u':
+					result.append(String.valueOf((d.get(Calendar.DAY_OF_WEEK)+5)%7+1));
+					break;
+				case 'U':
+					result.append(String.valueOf(weekNumber(d, 0)));
+					break;
+				case 'w':
+					result.append(String.valueOf((d.get(Calendar.DAY_OF_WEEK)+6)%7));
+					break;
+				case 'W': 
+					result.append(String.valueOf(weekNumber(d, 1)));
+					break;
+				case 'x':
+				case 'D':
+					result.append(date("%m/%d/%y", time));
+					break;
+				case 'X':
+				case 'T':
+					result.append(date("%H:%M:%S", time));
+					break;
+				case 'y':
+					result.append(String.valueOf(d.get(Calendar.YEAR)).substring(2));
+					break;
+				case 'Y':
+					result.append(String.valueOf(d.get(Calendar.YEAR)));
+					break;
+				case 'z': {
+					final int tzo = d.getTimeZone().getRawOffset() / (60 * 1000);
+					result.append((tzo>0? "+": "") + String.valueOf(tzo));
+					break;
+				}
+				case 'Z':
+					break;
+				}
+			}
+		}
+		return result.tojstring();
 	}
+	
+	private static final String[] WeekdayNameAbbrev = { "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" };
+	private static final String[] WeekdayName = { "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday" };
+	private static final String[] MonthNameAbbrev = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };
+	private static final String[] MonthName = { "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December" };
 
+	private Calendar beginningOfYear(Calendar d) {
+		Calendar y0 = Calendar.getInstance();
+		y0.setTime(d.getTime());
+		y0.set(Calendar.MONTH, 0);
+		y0.set(Calendar.DAY_OF_MONTH, 1);
+		y0.set(Calendar.HOUR_OF_DAY, 0);
+		y0.set(Calendar.MINUTE, 0);
+		y0.set(Calendar.SECOND, 0);
+		return y0;
+	}
+	
+	private int weekNumber(Calendar d, int startDay) {
+		Calendar y0 =  beginningOfYear(d);
+		System.out.println("Time  Date(time) " + d.getTime() + " y0 " + y0.getTime());
+		y0.set(Calendar.DAY_OF_MONTH, 1 + (startDay + 8 - y0.get(Calendar.DAY_OF_WEEK)) % 7);
+		if (y0.after(d)) {
+			y0.set(Calendar.YEAR, y0.get(Calendar.YEAR) - 1);
+			y0.set(Calendar.DAY_OF_MONTH, 1 + (startDay + 8 - y0.get(Calendar.DAY_OF_WEEK)) % 7);
+			System.out.println("  -> y0 " + y0.getTime());
+		}
+		long dt = d.getTime().getTime() - y0.getTime().getTime();
+		return 1 + (int) (dt / (7L * 24L * 3600L * 1000L));
+	}
+	
 	/** 
 	 * This function is equivalent to the C function system. 
 	 * It passes command to be executed by an operating system shell. 
@@ -305,7 +465,7 @@ public class OsLib extends TwoArgFunction {
 	 * @return long value for the time
 	 */
 	protected double time(LuaTable table) {
-		return System.currentTimeMillis() / 1000.0;
+		return (new java.util.Date()).getTime() / 1000.;
 	}
 
 	/**

test/junit/org/luaj/vm2/AllTests.java

@@ -35,6 +35,7 @@ import org.luaj.vm2.compiler.SimpleTests;
 import org.luaj.vm2.lib.jse.LuaJavaCoercionTest;
 import org.luaj.vm2.lib.jse.LuajavaAccessibleMembersTest;
 import org.luaj.vm2.lib.jse.LuajavaClassMembersTest;
+import org.luaj.vm2.lib.jse.OsLibTest;
 import org.luaj.vm2.script.ScriptEngineTests;
 
 public class AllTests {
@@ -81,6 +82,7 @@ public class AllTests {
 		lib.addTestSuite(LuajavaClassMembersTest.class);
 		lib.addTestSuite(LuaJavaCoercionTest.class);
 		lib.addTestSuite(RequireClassTest.class);
+		lib.addTestSuite(OsLibTest.class);
 		suite.addTest(lib);
 
 		// Script engine tests.

test/junit/org/luaj/vm2/lib/jse/OsLibTest.java

@@ -0,0 +1,71 @@
+package org.luaj.vm2.lib.jse;
+
+import org.luaj.vm2.lib.OsLib;
+
+import junit.framework.TestCase;
+
+public class OsLibTest extends TestCase {
+
+	OsLib lib;
+	double time;
+	
+	public void setUp() {
+		lib = new OsLib();
+		time = new java.util.Date(2001-1900, 7, 23, 14, 55, 02).getTime() / 1000.0;
+	}
+
+	void t(String format, String expected) {
+		String actual = lib.date(format, time);
+		assertEquals(expected, actual);
+	}
+	
+	public void testStringDateChars() { t("foo", "foo"); } 
+	public void testStringDate_a() { t("%a", "Thu"); } 
+	public void testStringDate_A() { t("%A", "Thursday"); } 
+	public void testStringDate_b() { t("%b", "Aug"); } 
+	public void testStringDate_B() { t("%B", "August"); } 
+	public void testStringDate_c() { t("%c", "Thu Aug 23 14:55:02 2001"); } 
+	public void testStringDate_C() { t("%C", "20"); } 
+	public void testStringDate_d() { t("%d", "23"); } 
+	public void testStringDate_D() { t("%D", "08/23/01"); } 
+	public void testStringDate_e() { t("%e", "23"); } 
+	public void testStringDate_F() { t("%F", "2001-08-23"); } 
+	public void testStringDate_g() { t("%g", "%g"); } // not implemented.
+	public void testStringDate_G() { t("%G", "%G"); } // not implemented.
+	public void testStringDate_h() { t("%h", "Aug"); } 
+	public void testStringDate_H() { t("%H", "14"); } 
+	public void testStringDate_I() { t("%I", "02"); } 
+	public void testStringDate_j() { t("%j", "235"); } 
+	public void testStringDate_m() { t("%m", "08"); } 
+	public void testStringDate_M() { t("%M", "55"); } 
+	public void testStringDate_n() { t("%n", "\n"); } 
+	public void testStringDate_p() { t("%p", "PM"); } 
+	public void testStringDate_r() { t("%r", "02:55:02 pm"); } 
+	public void testStringDate_R() { t("%R", "14:55"); } 
+	public void testStringDate_S() { t("%S", "02"); } 
+	public void testStringDate_t() { t("%t", "\t"); } 
+	public void testStringDate_T() { t("%T", "14:55:02"); } 
+	public void testStringDate_u() { t("%u", "4"); } 
+	public void testStringDate_U() { t("%U", "33"); }
+	public void testStringDate_V() { t("%V", "%V"); } // not implemented.
+	public void testStringDate_w() { t("%w", "4"); } 
+	public void testStringDate_W() { t("%W", "34"); } 
+	public void testStringDate_x() { t("%x", "08/23/01"); } 
+	public void testStringDate_X() { t("%X", "14:55:02"); } 
+	public void testStringDate_y() { t("%y", "01"); } 
+	public void testStringDate_Y() { t("%Y", "2001"); } 
+	public void testStringDate_z() { t("%z", "-480"); } 
+	public void testStringDate_Z() { t("%Z", ""); } 
+	public void testStringDate_Pct() { t("%%", "%"); } 
+
+	static final double DAY = 24. * 3600.;
+	public void testStringDate_UW_neg4() { time-=4*DAY; t("%c %U %W", "Sun Aug 19 14:55:02 2001 33 33"); } 
+	public void testStringDate_UW_neg3() { time-=3*DAY; t("%c %U %W", "Mon Aug 20 14:55:02 2001 33 34"); } 
+	public void testStringDate_UW_neg2() { time-=2*DAY; t("%c %U %W", "Tue Aug 21 14:55:02 2001 33 34"); } 
+	public void testStringDate_UW_neg1() { time-=DAY; t("%c %U %W", "Wed Aug 22 14:55:02 2001 33 34"); } 
+	public void testStringDate_UW_pos0() { time+=0; t("%c %U %W", "Thu Aug 23 14:55:02 2001 33 34"); } 
+	public void testStringDate_UW_pos1() { time+=DAY; t("%c %U %W", "Fri Aug 24 14:55:02 2001 33 34"); } 
+	public void testStringDate_UW_pos2() { time+=2*DAY; t("%c %U %W", "Sat Aug 25 14:55:02 2001 33 34"); } 
+	public void testStringDate_UW_pos3() { time+=3*DAY; t("%c %U %W", "Sun Aug 26 14:55:02 2001 34 34"); } 
+	public void testStringDate_UW_pos4() { time+=4*DAY; t("%c %U %W", "Mon Aug 27 14:55:02 2001 34 35"); } 
+}