restore backwards compatibility (see clock-44.3) - spaces between tokens are optional, repaired greedy search (minLen), which find start next token or space now;

it is also more consistent than old engine now (covered by clock-44.4)

Author: sebres

generic/tclClockFmt.c

@@ -28,6 +28,10 @@ TCL_DECLARE_MUTEX(ClockFmtMutex);	/* Serializes access to common format list. */
 static void		ClockFmtScnStorageDelete(ClockFmtScnStorage *fss);
 static void		ClockFrmScnFinalize(void *);
 
+#ifndef TCL_CLOCK_FULL_COMPAT
+#define TCL_CLOCK_FULL_COMPAT 1
+#endif
+
 /*
  * Derivation of tclStringHashKeyType with another allocEntryProc
  */
@@ -1018,7 +1022,8 @@ static const char *
 FindTokenBegin(
     const char *p,
     const char *end,
-    ClockScanToken *tok)
+    ClockScanToken *tok,
+    int flags)
 {
     if (p < end) {
 	char c;
@@ -1027,23 +1032,35 @@ FindTokenBegin(
 	switch (tok->map->type) {
 	case CTOKT_INT:
 	case CTOKT_WIDE:
-	    /* should match at least one digit */
-	    while (!isdigit(UCHAR(*p)) && (p = Tcl_UtfNext(p)) < end) {}
+	    if (!(flags & CLF_STRICT)) {
+		/* should match at least one digit or space */
+		while (!isdigit(UCHAR(*p)) && !isspace(UCHAR(*p)) &&
+			(p = Tcl_UtfNext(p)) < end) {}
+	    } else {
+		/* should match at least one digit */
+		while (!isdigit(UCHAR(*p)) && (p = Tcl_UtfNext(p)) < end) {}
+	    }
 	    return p;
 
 	case CTOKT_WORD:
 	    c = *(tok->tokWord.start);
-	    /* should match at least to the first char of this word */
-	    while (*p != c && (p = Tcl_UtfNext(p)) < end) {}
-	    return p;
+	    goto findChar;
 
 	case CTOKT_SPACE:
 	    while (!isspace(UCHAR(*p)) && (p = Tcl_UtfNext(p)) < end) {}
 	    return p;
 
 	case CTOKT_CHAR:
 	    c = *((char *)tok->map->data);
-	    while (*p != c && (p = Tcl_UtfNext(p)) < end) {}
+findChar:
+	    if (!(flags & CLF_STRICT)) {
+		/* should match the char or space */
+		while (*p != c && !isspace(UCHAR(*p)) &&
+			(p = Tcl_UtfNext(p)) < end) {}
+	    } else {
+		/* should match the char */
+		while (*p != c && (p = Tcl_UtfNext(p)) < end) {}
+	    }
 	    return p;
 	}
     }
@@ -1068,6 +1085,7 @@ FindTokenBegin(
 
 static void
 DetermineGreedySearchLen(
+    ClockFmtScnCmdArgs *opts,
     DateInfo *info,
     ClockScanToken *tok,
     int *minLenPtr,
@@ -1082,7 +1100,8 @@ DetermineGreedySearchLen(
     if ((tok + 1)->map) {
 	end -= tok->endDistance + yySpaceCount;
 	/* find position of next known token */
-	p = FindTokenBegin(p, end, tok + 1);
+	p = FindTokenBegin(p, end, tok + 1,
+		TCL_CLOCK_FULL_COMPAT ? opts->flags : CLF_STRICT);
 	if (p < end) {
 	    minLen = p - yyInput;
 	}
@@ -1133,7 +1152,8 @@ DetermineGreedySearchLen(
 
 	    /* try to find laTok between [lookAhMin, lookAhMax] */
 	    while (minLen < maxLen) {
-		const char *f = FindTokenBegin(p, end, laTok);
+		const char *f = FindTokenBegin(p, end, laTok,
+				    TCL_CLOCK_FULL_COMPAT ? opts->flags : CLF_STRICT);
 		/* if found (not below lookAhMax) */
 		if (f < end) {
 		    break;
@@ -1517,7 +1537,7 @@ ClockScnToken_Month_Proc(
     int minLen, maxLen;
     TclStrIdxTree *idxTree;
 
-    DetermineGreedySearchLen(info, tok, &minLen, &maxLen);
+    DetermineGreedySearchLen(opts, info, tok, &minLen, &maxLen);
 
     /* get or create tree in msgcat dict */
 
@@ -1549,7 +1569,7 @@ ClockScnToken_DayOfWeek_Proc(
     char curTok = *tok->tokWord.start;
     TclStrIdxTree *idxTree;
 
-    DetermineGreedySearchLen(info, tok, &minLen, &maxLen);
+    DetermineGreedySearchLen(opts, info, tok, &minLen, &maxLen);
 
     /* %u %w %Ou %Ow */
     if (curTok != 'a' && curTok != 'A'
@@ -1620,7 +1640,7 @@ ClockScnToken_amPmInd_Proc(
     int minLen, maxLen;
     Tcl_Obj *amPmObj[2];
 
-    DetermineGreedySearchLen(info, tok, &minLen, &maxLen);
+    DetermineGreedySearchLen(opts, info, tok, &minLen, &maxLen);
 
     amPmObj[0] = ClockMCGet(opts, MCLIT_AM);
     amPmObj[1] = ClockMCGet(opts, MCLIT_PM);
@@ -1655,7 +1675,7 @@ ClockScnToken_LocaleERA_Proc(
     int minLen, maxLen;
     Tcl_Obj *eraObj[6];
 
-    DetermineGreedySearchLen(info, tok, &minLen, &maxLen);
+    DetermineGreedySearchLen(opts, info, tok, &minLen, &maxLen);
 
     eraObj[0] = ClockMCGet(opts, MCLIT_BCE);
     eraObj[1] = ClockMCGet(opts, MCLIT_CE);
@@ -1692,7 +1712,7 @@ ClockScnToken_LocaleListMatcher_Proc(
     int minLen, maxLen;
     TclStrIdxTree *idxTree;
 
-    DetermineGreedySearchLen(info, tok, &minLen, &maxLen);
+    DetermineGreedySearchLen(opts, info, tok, &minLen, &maxLen);
 
     /* get or create tree in msgcat dict */
 
@@ -1715,7 +1735,7 @@ ClockScnToken_LocaleListMatcher_Proc(
 
 static int
 ClockScnToken_JDN_Proc(
-    TCL_UNUSED(ClockFmtScnCmdArgs *),
+    ClockFmtScnCmdArgs *opts,
     DateInfo *info,
     ClockScanToken *tok)
 {
@@ -1724,7 +1744,7 @@ ClockScnToken_JDN_Proc(
     Tcl_WideInt intJD;
     int fractJD = 0, fractJDDiv = 1;
 
-    DetermineGreedySearchLen(info, tok, &minLen, &maxLen);
+    DetermineGreedySearchLen(opts, info, tok, &minLen, &maxLen);
 
     end = yyInput + maxLen;
 
@@ -1795,7 +1815,7 @@ ClockScnToken_TimeZone_Proc(
     const char *p = yyInput;
     Tcl_Obj *tzObjStor = NULL;
 
-    DetermineGreedySearchLen(info, tok, &minLen, &maxLen);
+    DetermineGreedySearchLen(opts, info, tok, &minLen, &maxLen);
 
     /* numeric timezone */
     if (*p == '+' || *p == '-') {
@@ -1878,7 +1898,7 @@ ClockScnToken_TimeZone_Proc(
 
 static int
 ClockScnToken_StarDate_Proc(
-    TCL_UNUSED(ClockFmtScnCmdArgs *),
+    ClockFmtScnCmdArgs *opts,
     DateInfo *info,
     ClockScanToken *tok)
 {
@@ -1887,7 +1907,7 @@ ClockScnToken_StarDate_Proc(
     int year, fractYear, fractDayDiv, fractDay;
     static const char *stardatePref = "stardate ";
 
-    DetermineGreedySearchLen(info, tok, &minLen, &maxLen);
+    DetermineGreedySearchLen(opts, info, tok, &minLen, &maxLen);
 
     end = yyInput + maxLen;
 
@@ -2435,7 +2455,7 @@ ClockScan(
 		}
 	    }
 
-	    DetermineGreedySearchLen(info, tok, &minLen, &size);
+	    DetermineGreedySearchLen(opts, info, tok, &minLen, &size);
 
 	    if (size < map->minSize) {
 		/* missing input -> error */

tests/clock.test

@@ -37039,12 +37039,18 @@ test clock-44.2 {regression test - time zone containing only two digits} \
     } \
     -result 482134530
 
-test clock-44.3 {regression test - spaces between some scan tokens are optional} \
+test clock-44.3 {regression test - spaces between some scan tokens are optional (TCL_CLOCK_FULL_COMPAT, no-strict only)} \
     -body {
 	list [clock scan {9 Apr 2024} -format {%d %b%Y} -gmt 1] \
 	     [clock scan {Tue, 9 Apr 2024 00:00:00 +0000} -format {%a, %d %b%Y %H:%M:%S %Z} -gmt 1]
     } \
     -result {1712620800 1712620800}
+test clock-44.4 {regression test - spaces between all scan tokens are optional (TCL_CLOCK_FULL_COMPAT, no-strict only)} \
+    -body {
+	list [clock scan {9 Apr 2024} -format {%d%b%Y} -gmt 1] \
+	     [clock scan {Tue, 9 Apr 2024 00:00:00 +0000} -format {%a,%d%b%Y%H:%M:%S%Z} -gmt 1]
+    } \
+    -result {1712620800 1712620800}
 
 test clock-45.1 {compat: scan regression on spaces (multiple spaces in format)} \
     -body {