closes tcl-core [cd25761979]: clock format and clock add will accept now as clock value (value -now retained to compat reasons to earlier versions and tclclockmod, undocumented at the moment)

back-porting from https://core.tcl-lang.org/tcl/ci/f602e32fc3

Author: sebres

doc/clock.n

@@ -87,14 +87,14 @@ slowing its clock by a tiny fraction for some minutes until it is
 back in sync with UTC; its data model does not represent minutes that
 have 59 or 61 seconds.
 .TP
-\fI\-now\fR
-Instead of \fItimeVal\fR a non-integer option \fI\-now\fR can be used as
+\fI\now\fR
+Instead of \fItimeVal\fR a non-integer option \fI\now\fR can be used as
 replacement for today, which is simply interpolated to the runt-time as value
 of \fBclock seconds\fR. For example:
 .sp
-\fBclock format -now -f %a; # current day of the week\fR
+\fBclock format now -f %a; # current day of the week\fR
 .sp
-\fBclock add -now 1 month; # next month\fR
+\fBclock add now 1 month; # next month\fR
 .TP
 \fIunit\fR
 One of the words, \fBseconds\fR, \fBminutes\fR, \fBhours\fR,

generic/tclClock.c

@@ -3432,28 +3432,26 @@ ClockParseFmtScnArgs(
     /* Base (by scan or add) or clock value (by format) */
 
     if (opts->baseObj != NULL) {
-	register Tcl_Obj *baseObj = opts->baseObj;
-	/* bypass integer recognition if looks like option "-now" */
-	if (
-	    (baseObj->length == 4 && baseObj->bytes && *(baseObj->bytes+1) == 'n') ||
-	    TclGetWideIntFromObj(NULL, baseObj, &baseVal) != TCL_OK
-	) {
-
-	    /* we accept "-now" as current date-time */
+	Tcl_Obj *baseObj = opts->baseObj;
+
+	/* bypass integer recognition if looks like "now" or "-now" */
+	if ((baseObj->bytes && 
+		((baseObj->length == 3 && baseObj->bytes[0] == 'n') ||
+		 (baseObj->length == 4 && baseObj->bytes[1] == 'n')))
+		|| TclGetWideIntFromObj(NULL, baseObj, &baseVal) != TCL_OK) {
+	    /* we accept "now" and "-now" as current date-time */
 	    static const char *const nowOpts[] = {
-		"-now", NULL
+		"now", "-now", NULL
 	    };
 	    int idx;
-	    if (Tcl_GetIndexFromObj(NULL, baseObj, nowOpts, "seconds or -now",
-		    TCL_EXACT, &idx) == TCL_OK
-	    ) {
+	    if (Tcl_GetIndexFromObj(NULL, baseObj, nowOpts, "seconds",
+		    TCL_EXACT, &idx) == TCL_OK) {
 		goto baseNow;
 	    }
 
 	    Tcl_SetObjResult(interp, Tcl_ObjPrintf(
-		    "expected integer but got \"%s\"",
-		    Tcl_GetString(baseObj)));
-	    Tcl_SetErrorCode(interp, "TCL", "VALUE", "INTEGER", NULL);
+		"bad seconds \"%s\": must be now or integer",
+		TclGetString(baseObj)));
 	    i = 1;
 	    goto badOption;
 	}
@@ -3550,9 +3548,8 @@ ClockFormatObjCmd(
     int objc,			/* Parameter count */
     Tcl_Obj *const objv[])	/* Parameter values */
 {
-    ClockClientData *dataPtr = clientData;
-
-    static const char *syntax = "clock format clockval|-now "
+    ClockClientData *dataPtr = (ClockClientData *)clientData;
+    static const char *syntax = "clock format clockval|now "
 	"?-format string? "
 	"?-gmt boolean? "
 	"?-locale LOCALE? ?-timezone ZONE?";
@@ -4398,7 +4395,7 @@ ClockAddObjCmd(
     int objc,			/* Parameter count */
     Tcl_Obj *const objv[])	/* Parameter values */
 {
-    static const char *syntax = "clock add clockval|-now ?number units?..."
+    static const char *syntax = "clock add clockval|now ?number units?..."
 	"?-gmt boolean? "
 	"?-locale LOCALE? ?-timezone ZONE?";
     ClockClientData *dataPtr = clientData;

tests/clock.test

@@ -284,7 +284,7 @@ test clock-0.1 "initial: auto-loading of ensemble and stubs on demand" no_tclclo
 	clock seconds; # init ensemble (but not yet stubs, loading of clock.tcl retarded)
 	lappend ret ens:[namespace ensemble exists ::clock]
 	lappend ret stubs:[expr {[namespace which -command ::tcl::clock::GetSystemTimeZone] ne ""}]
-	clock format -now; # clock.tcl stubs expected
+	clock format now; # clock.tcl stubs expected
 	lappend ret stubs:[expr {[namespace which -command ::tcl::clock::GetSystemTimeZone] ne ""}]
     }]
     interp delete $i
@@ -300,14 +300,14 @@ test clock-0.2 "initial: loading of format/locale does not overwrite interp stat
     if {[catch {
 	return -level 0 -code error -errorcode {EXPERR TEST-ERROR} -errorinfo "ERROR expected error" test
     }]} {
-	clock format -now -locale de; # should not overwrite error code/info
+	clock format now -locale de; # should not overwrite error code/info
 	list $::errorCode $::errorInfo
     }
 } -result {{EXPERR TEST-ERROR} {ERROR expected error}}
 
 # Test some of the basics of [clock format]
 
-set syntax "clock format clockval|-now ?-format string? ?-gmt boolean? ?-locale LOCALE? ?-timezone ZONE?"
+set syntax "clock format clockval|now ?-format string? ?-gmt boolean? ?-locale LOCALE? ?-timezone ZONE?"
 test clock-1.0 "clock format - wrong # args" {
     list [catch {clock format} msg] $msg $::errorCode
 } [subst {1 {wrong # args: should be "$syntax"} {CLOCK wrongNumArgs}}]
@@ -318,7 +318,7 @@ test clock-1.0.1 "clock format - wrong # args (compiled ensemble with invalid sy
 
 test clock-1.1 "clock format - bad time" {
     list [catch {clock format foo} msg] $msg
-} {1 {expected integer but got "foo"}}
+} {1 {bad seconds "foo": must be now or integer}}
 
 test clock-1.2 "clock format - bad gmt val" {
     list [catch {clock format 0 -gmt foo} msg] $msg
@@ -353,10 +353,10 @@ test clock-1.7.1 "clock format - command abbreviations (compat regression test)"
     clock f 0 -g 1 -f "%Y-%m-%d"
 } 1970-01-01
 
-test clock-1.8 "clock format -now" {
+test clock-1.8 "clock format now" {
     # give one second more for test (if on boundary of the current second):
     set n [clock format [clock seconds] -g 1 -f "%s"]
-    expr {[clock format -now -g 1 -f "%s"] in [list $n [incr n]]}
+    expr {[clock format now -g 1 -f "%s"] in [list $n [incr n]]}
 } 1
 
 test clock-1.9 "clock arguments: option doubly present" {