Improve compatibility of os.date() function

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

@@ -24,7 +24,6 @@ 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;
@@ -139,8 +138,23 @@ public class OsLib extends TwoArgFunction {
 				case CLOCK:
 					return valueOf(clock());
 				case DATE: {
-					String s = args.optjstring(1, null);
+					String s = args.optjstring(1, "%c");
-					double t = args.optdouble(2,-1);
+					double t = args.isnumber(2)? args.todouble(2): time(null);
+					if (s.equals("*t")) {
+						Calendar d = Calendar.getInstance();
+						d.setTime(new Date((long)(t*1000)));
+						LuaTable tbl = LuaValue.tableOf();
+						tbl.set("year", LuaValue.valueOf(d.get(Calendar.YEAR)));
+						tbl.set("month", LuaValue.valueOf(d.get(Calendar.MONTH)+1));
+						tbl.set("day", LuaValue.valueOf(d.get(Calendar.DAY_OF_MONTH)));
+						tbl.set("hour", LuaValue.valueOf(d.get(Calendar.HOUR)));
+						tbl.set("min", LuaValue.valueOf(d.get(Calendar.MINUTE)));
+						tbl.set("sec", LuaValue.valueOf(d.get(Calendar.SECOND)));
+						tbl.set("wday", LuaValue.valueOf(d.get(Calendar.DAY_OF_WEEK)));
+						tbl.set("yday", LuaValue.valueOf(d.get(Calendar.DAY_OF_YEAR)));
+						tbl.set("isdst", LuaValue.valueOf(isDaylightSavingsTime(d)));
+						return tbl;
+					}
 					return valueOf( date(s, t==-1? time(null): t) );
 				}
 				case DIFFTIME:
@@ -164,8 +178,9 @@ public class OsLib extends TwoArgFunction {
 					String s = setlocale(args.optjstring(1,null), args.optjstring(2, "all"));
 					return s!=null? valueOf(s): NIL;
 				}
-				case TIME:
+				case TIME: {
 					return valueOf(time(args.arg1().isnil()? null: args.checktable(1)));
+				}
 				case TMPNAME:
 					return valueOf(tmpname());
 				}
@@ -215,13 +230,17 @@ public class OsLib extends TwoArgFunction {
 	 * formatted according to the given string format.
 	 */
 	public String date(String format, double time) {
+		Calendar d = Calendar.getInstance();
+		d.setTime(new Date((long)(time*1000)));
+		if (format.startsWith("!")) {
+			time -= timeZoneOffset(d);
+			d.setTime(new Date((long)(time*1000)));
+			format = format.substring(1);
+		}
 		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':
@@ -234,8 +253,7 @@ public class OsLib extends TwoArgFunction {
 				if (i >= n) break;
 				switch ( c = fmt[i++ ] ) {
 				default:
-					result.append( (byte)'%' );
+					LuaValue.argerror(1, "invalid conversion specifier '%"+c+"'");
-					result.append( (byte)c );
 					break;
 				case '%':
 					result.append( (byte)'%' );
@@ -247,7 +265,6 @@ public class OsLib extends TwoArgFunction {
 					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':
@@ -256,22 +273,9 @@ public class OsLib extends TwoArgFunction {
 				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;
@@ -290,30 +294,12 @@ public class OsLib extends TwoArgFunction {
 				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;
@@ -324,11 +310,9 @@ public class OsLib extends TwoArgFunction {
 					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':
@@ -338,12 +322,13 @@ public class OsLib extends TwoArgFunction {
 					result.append(String.valueOf(d.get(Calendar.YEAR)));
 					break;
 				case 'z': {
-					final int tzo = d.getTimeZone().getRawOffset() / (60 * 1000);
+					final int tzo = timeZoneOffset(d) / 60;
-					result.append((tzo>0? "+": "") + String.valueOf(tzo));
+					final int a = Math.abs(tzo);
+					final String h = String.valueOf(100 + a / 60).substring(1);
+					final String m = String.valueOf(100 + a % 60).substring(1);
+					result.append((tzo>=0? "+": "-") + h + m);
 					break;
 				}
-				case 'Z':
-					break;
 				}
 			}
 		}
@@ -368,17 +353,33 @@ public class OsLib extends TwoArgFunction {
 	
 	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));
 	}
 	
+	private int timeZoneOffset(Calendar d) {
+		int localStandarTimeMillis = ( 
+				d.get(Calendar.HOUR_OF_DAY) * 3600 +
+				d.get(Calendar.MINUTE) * 60 +
+				d.get(Calendar.SECOND)) * 1000;
+		return d.getTimeZone().getOffset(
+				1,
+				d.get(Calendar.YEAR),
+				d.get(Calendar.MONTH),
+				d.get(Calendar.DAY_OF_MONTH),
+				d.get(Calendar.DAY_OF_WEEK), 
+				localStandarTimeMillis) / 1000;
+	}
+	
+	private boolean isDaylightSavingsTime(Calendar d) {
+		return timeZoneOffset(d) != d.getTimeZone().getRawOffset() / 1000;		
+	}
+	
 	/** 
 	 * This function is equivalent to the C function system. 
 	 * It passes command to be executed by an operating system shell. 

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

@@ -25,37 +25,21 @@ public class OsLibTest extends TestCase {
 	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.;

test/lua/oslib.lua

@@ -37,3 +37,20 @@ print( 'os.remove(q)', pcall( os.remove, q ) )
 -- print( 'os.setlocale(nil,"all")', pcall( os.setlocale, nil, "all" ) )
 print( 'os.setlocale("C")', pcall( os.setlocale, "C" ) )
 print( 'os.exit', type(os.exit) )
+
+-- os.date() formatting
+local t = 1281364496  -- Aug 9, 2010, 2:34:56 PM (Monday)
+local function p(s)
+  if pcall(os.date, s, t) then
+	  print( "os.date('"..s.."', "..t..")", pcall(os.date, s, t))
+  end
+end
+for i= 65, 90 do
+  p('%'..string.char(i + 97 - 65))
+  p('%'..string.char(i))
+end
+local tbl = os.date('*t', t)
+for i,k in ipairs({'year', 'month', 'day', 'hour', 'min', 'sec', 'wday', 'yday', 'isdst'}) do
+	local v = tbl[k]
+	print('k', type(k), k, 'v', type(v), v)
+end