to_char(): Do not count negative sign as a digit for time values

For time masks, like HH24, MI, SS, CC, MM, do not count the negative
sign as part of the zero-padding length specified by the mask, e.g. have
to_char('-4 years'::interval, 'YY') return '-04', not '-4'.

Report by Craig Ringer

3 files changed, 24 insertions, 16 deletions

diff --git a/src/backend/utils/adt/formatting.c b/src/backend/utils/adt/formatting.c
index 5391ea0bf0b..5b09de32efc 100644
--- a/src/backend/utils/adt/formatting.c
+++ b/src/backend/utils/adt/formatting.c
@@ -2426,7 +2426,7 @@ DCH_to_char(FormatNode *node, bool is_interval, TmToChar *in, char *out, Oid col
 				 * display time as shown on a 12-hour clock, even for
 				 * intervals
 				 */
-				sprintf(s, "%0*d", S_FM(n->suffix) ? 0 : 2,
+				sprintf(s, "%0*d", S_FM(n->suffix) ? 0 : (tm->tm_hour >= 0) ? 2 : 3,
 				 tm->tm_hour % (HOURS_PER_DAY / 2) == 0 ? HOURS_PER_DAY / 2 :
 						tm->tm_hour % (HOURS_PER_DAY / 2));
 				if (S_THth(n->suffix))
@@ -2434,19 +2434,22 @@ DCH_to_char(FormatNode *node, bool is_interval, TmToChar *in, char *out, Oid col
 				s += strlen(s);
 				break;
 			case DCH_HH24:
-				sprintf(s, "%0*d", S_FM(n->suffix) ? 0 : 2, tm->tm_hour);
+				sprintf(s, "%0*d", S_FM(n->suffix) ? 0 : (tm->tm_hour >= 0) ? 2 : 3,
+						tm->tm_hour);
 				if (S_THth(n->suffix))
 					str_numth(s, s, S_TH_TYPE(n->suffix));
 				s += strlen(s);
 				break;
 			case DCH_MI:
-				sprintf(s, "%0*d", S_FM(n->suffix) ? 0 : 2, tm->tm_min);
+				sprintf(s, "%0*d", S_FM(n->suffix) ? 0 : (tm->tm_min >= 0) ? 2 : 3,
+						tm->tm_min);
 				if (S_THth(n->suffix))
 					str_numth(s, s, S_TH_TYPE(n->suffix));
 				s += strlen(s);
 				break;
 			case DCH_SS:
-				sprintf(s, "%0*d", S_FM(n->suffix) ? 0 : 2, tm->tm_sec);
+				sprintf(s, "%0*d", S_FM(n->suffix) ? 0 : (tm->tm_sec >= 0) ? 2 : 3,
+						tm->tm_sec);
 				if (S_THth(n->suffix))
 					str_numth(s, s, S_TH_TYPE(n->suffix));
 				s += strlen(s);
@@ -2503,7 +2506,8 @@ DCH_to_char(FormatNode *node, bool is_interval, TmToChar *in, char *out, Oid col
 				break;
 			case DCH_OF:
 				INVALID_FOR_INTERVAL;
-				sprintf(s, "%+0*d", S_FM(n->suffix) ? 0 : 3, (int) tm->tm_gmtoff / SECS_PER_HOUR);
+				sprintf(s, "%+0*d", S_FM(n->suffix) ? 0 : (tm->tm_gmtoff >= 0) ? 3 : 4,
+						(int) tm->tm_gmtoff / SECS_PER_HOUR);
 				s += strlen(s);
 				if ((int) tm->tm_gmtoff % SECS_PER_HOUR != 0)
 				{
@@ -2653,7 +2657,8 @@ DCH_to_char(FormatNode *node, bool is_interval, TmToChar *in, char *out, Oid col
 				s += strlen(s);
 				break;
 			case DCH_MM:
-				sprintf(s, "%0*d", S_FM(n->suffix) ? 0 : 2, tm->tm_mon);
+				sprintf(s, "%0*d", S_FM(n->suffix) ? 0 : (tm->tm_mon >= 0) ? 2 : 3,
+						tm->tm_mon);
 				if (S_THth(n->suffix))
 					str_numth(s, s, S_TH_TYPE(n->suffix));
 				s += strlen(s);
@@ -2828,7 +2833,7 @@ DCH_to_char(FormatNode *node, bool is_interval, TmToChar *in, char *out, Oid col
 						i = tm->tm_year / 100 - 1;
 				}
 				if (i <= 99 && i >= -99)
-					sprintf(s, "%0*d", S_FM(n->suffix) ? 0 : 2, i);
+					sprintf(s, "%0*d", S_FM(n->suffix) ? 0 : (i >= 0) ? 2 : 3, i);
 				else
 					sprintf(s, "%d", i);
 				if (S_THth(n->suffix))
@@ -2846,7 +2851,8 @@ DCH_to_char(FormatNode *node, bool is_interval, TmToChar *in, char *out, Oid col
 			case DCH_YYYY:
 			case DCH_IYYY:
 				sprintf(s, "%0*d",
-						S_FM(n->suffix) ? 0 : 4,
+						S_FM(n->suffix) ? 0 :
+						(ADJUST_YEAR(tm->tm_year, is_interval) >= 0) ? 4 : 5,
 						(n->key->id == DCH_YYYY ?
 						 ADJUST_YEAR(tm->tm_year, is_interval) :
 						 ADJUST_YEAR(date2isoyear(tm->tm_year,
@@ -2860,7 +2866,8 @@ DCH_to_char(FormatNode *node, bool is_interval, TmToChar *in, char *out, Oid col
 			case DCH_YYY:
 			case DCH_IYY:
 				sprintf(s, "%0*d",
-						S_FM(n->suffix) ? 0 : 3,
+						S_FM(n->suffix) ? 0 :
+						(ADJUST_YEAR(tm->tm_year, is_interval) >= 0) ? 3 : 4,
 						(n->key->id == DCH_YYY ?
 						 ADJUST_YEAR(tm->tm_year, is_interval) :
 						 ADJUST_YEAR(date2isoyear(tm->tm_year,
@@ -2874,7 +2881,8 @@ DCH_to_char(FormatNode *node, bool is_interval, TmToChar *in, char *out, Oid col
 			case DCH_YY:
 			case DCH_IY:
 				sprintf(s, "%0*d",
-						S_FM(n->suffix) ? 0 : 2,
+						S_FM(n->suffix) ? 0 :
+						(ADJUST_YEAR(tm->tm_year, is_interval) >= 0) ? 2 : 3,
 						(n->key->id == DCH_YY ?
 						 ADJUST_YEAR(tm->tm_year, is_interval) :
 						 ADJUST_YEAR(date2isoyear(tm->tm_year,
diff --git a/src/test/regress/expected/timestamp.out b/src/test/regress/expected/timestamp.out
index a092fc25eb7..e9f5e7790f5 100644
--- a/src/test/regress/expected/timestamp.out
+++ b/src/test/regress/expected/timestamp.out
@@ -948,8 +948,8 @@ SELECT '' AS to_char_2, to_char(d1, 'FMDAY FMDay FMday FMMONTH FMMonth FMmonth F
 
 SELECT '' AS to_char_3, to_char(d1, 'Y,YYY YYYY YYY YY Y CC Q MM WW DDD DD D J')
    FROM TIMESTAMP_TBL;
- to_char_3 |                     to_char                     
------------+-------------------------------------------------
+ to_char_3 |                     to_char                      
+-----------+--------------------------------------------------
            | 
            | 
            | 1,970 1970 970 70 0 20 1 01 01 001 01 5 2440588
@@ -992,7 +992,7 @@ SELECT '' AS to_char_3, to_char(d1, 'Y,YYY YYYY YYY YY Y CC Q MM WW DDD DD D J')
            | 1,997 1997 997 97 7 20 1 02 07 045 14 6 2450494
            | 1,997 1997 997 97 7 20 1 02 07 046 15 7 2450495
            | 1,997 1997 997 97 7 20 1 02 07 047 16 1 2450496
-           | 0,097 0097 097 97 7 -1 1 02 07 047 16 3 1686042
+           | 0,097 0097 097 97 7 -01 1 02 07 047 16 3 1686042
            | 0,097 0097 097 97 7 01 1 02 07 047 16 7 1756536
            | 0,597 0597 597 97 7 06 1 02 07 047 16 5 1939157
            | 1,097 1097 097 97 7 11 1 02 07 047 16 3 2121778
diff --git a/src/test/regress/expected/timestamptz.out b/src/test/regress/expected/timestamptz.out
index e5a21305c00..40a22540e55 100644
--- a/src/test/regress/expected/timestamptz.out
+++ b/src/test/regress/expected/timestamptz.out
@@ -1029,8 +1029,8 @@ SELECT '' AS to_char_2, to_char(d1, 'FMDAY FMDay FMday FMMONTH FMMonth FMmonth F
 
 SELECT '' AS to_char_3, to_char(d1, 'Y,YYY YYYY YYY YY Y CC Q MM WW DDD DD D J')
    FROM TIMESTAMPTZ_TBL;
- to_char_3 |                     to_char                     
------------+-------------------------------------------------
+ to_char_3 |                     to_char                      
+-----------+--------------------------------------------------
            | 
            | 
            | 1,969 1969 969 69 9 20 4 12 53 365 31 4 2440587
@@ -1074,7 +1074,7 @@ SELECT '' AS to_char_3, to_char(d1, 'Y,YYY YYYY YYY YY Y CC Q MM WW DDD DD D J')
            | 1,997 1997 997 97 7 20 1 02 07 045 14 6 2450494
            | 1,997 1997 997 97 7 20 1 02 07 046 15 7 2450495
            | 1,997 1997 997 97 7 20 1 02 07 047 16 1 2450496
-           | 0,097 0097 097 97 7 -1 1 02 07 047 16 3 1686042
+           | 0,097 0097 097 97 7 -01 1 02 07 047 16 3 1686042
            | 0,097 0097 097 97 7 01 1 02 07 047 16 7 1756536
            | 0,597 0597 597 97 7 06 1 02 07 047 16 5 1939157
            | 1,097 1097 097 97 7 11 1 02 07 047 16 3 2121778