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Re: [PATCH] Round-down years in "years+months" relative date view

From
Alex Riesen <raa.lkml@gmail.com>
Date
Aug 28, 2009, 19:03 UTC
Message-ID
<20090828190319.GA9233@blimp.localdomain>
In-Reply-To
<alpine.LFD.2.00.0908281307510.6044@xanadu.home>
>From b51bc56816490c71cd37f52be73a06cef6b9bf14 Mon Sep 17 00:00:00 2001
From: Alex Riesen <raa.lkml@gmail.com>
Date: Fri, 28 Aug 2009 20:59:59 +0200
Subject: [PATCH] Add date formatting functions with current time explicitely formatted

It should allow safe testing of this part of the code. --- Nicolas Pitre, Fri, Aug 28, 2009 19:28:34 +0200:

Show 25 quoted lines
> On Fri, 28 Aug 2009, Jeff King wrote:
> > On Fri, Aug 28, 2009 at 09:58:27AM +0200, Alex Riesen wrote:
> > 
> > > > I couldn't find any tests related to relative date processing, so it
> > > > would be really nice to have some. But I'm not sure of the best way to
> > > > do it without dealing with race conditions. Annoyingly, show_date calls
> > > > gettimeofday at a pretty low level, so there isn't a way of
> > > > instrumenting it short of LD_PRELOAD trickery (which is probably not
> > > > very portable).
> > > 
> > > Maybe better prepare the _test_ so that it uses current time and time
> > > arithmetics then put yet another cludge in operational code? Especially
> > > when we already have a greate number of GIT_ environment variables,
> > > documented nowhere, with effects not immediately obvious:
> > 
> > But that's the point: you can't do that without a race condition. Your
> > test gets a sense of the current time, then runs git, which checks the
> > current time again. How many seconds elapsed between the two checks?
> > 
> > I guess it is good enough for testing large time spans, but I was hoping
> > for a comprehensive time test.
> 
> I agree with your concern.  This is why I created the --index-version 
> switch to pack-objects.
> 
This is what I mean with "supplying current time":
 cache.h |    2 +
 date.c  |  130 ++++++++++++++++++++++++++++++++++----------------------------
 2 files changed, 73 insertions(+), 59 deletions(-)
diff --git a/cache.h b/cache.h
index dd7f71e..3fb0166 100644
--- a/cache.h
+++ b/cache.h
@@ -731,9 +731,11 @@ enum date_mode {
 };
 
 const char *show_date(unsigned long time, int timezone, enum date_mode mode);
+const char *show_date_relative(unsigned long time, int tz, const struct timeval *now);
 int parse_date(const char *date, char *buf, int bufsize);
 void datestamp(char *buf, int bufsize);
 unsigned long approxidate(const char *);
+unsigned long approxidate_relative(const char *date, const struct timeval *now);
 enum date_mode parse_date_format(const char *format);
 
 #define IDENT_WARN_ON_NO_NAME  1
diff --git a/date.c b/date.c
index 409a17d..08b4b49 100644
--- a/date.c
+++ b/date.c
@@ -84,6 +84,67 @@ static int local_tzoffset(unsigned long time)
 	return offset * eastwest;
 }
 
+const char *show_date_relative(unsigned long time, int tz, const struct timeval *now)
+{
+	static char timebuf[100 /* TODO: can be optimized */];
+	unsigned long diff;
+	if (now->tv_sec < time)
+		return "in the future";
+	diff = now->tv_sec - time;
+	if (diff < 90) {
+		snprintf(timebuf, sizeof(timebuf), "%lu seconds ago", diff);
+		return timebuf;
+	}
+	/* Turn it into minutes */
+	diff = (diff + 30) / 60;
+	if (diff < 90) {
+		snprintf(timebuf, sizeof(timebuf), "%lu minutes ago", diff);
+		return timebuf;
+	}
+	/* Turn it into hours */
+	diff = (diff + 30) / 60;
+	if (diff < 36) {
+		snprintf(timebuf, sizeof(timebuf), "%lu hours ago", diff);
+		return timebuf;
+	}
+	/* We deal with number of days from here on */
+	diff = (diff + 12) / 24;
+	if (diff < 14) {
+		snprintf(timebuf, sizeof(timebuf), "%lu days ago", diff);
+		return timebuf;
+	}
+	/* Say weeks for the past 10 weeks or so */
+	if (diff < 70) {
+		snprintf(timebuf, sizeof(timebuf), "%lu weeks ago", (diff + 3) / 7);
+		return timebuf;
+	}
+	/* Say months for the past 12 months or so */
+	if (diff < 360) {
+		snprintf(timebuf, sizeof(timebuf), "%lu months ago", (diff + 15) / 30);
+		return timebuf;
+	}
+	/* Give years and months for 5 years or so */
+	if (diff < 1825) {
+		unsigned long years = (diff + 183) / 365;
+		unsigned long months = (diff % 365 + 15) / 30;
+		int n;
+		n = snprintf(timebuf, sizeof(timebuf), "%lu year%s",
+			     years, (years > 1 ? "s" : ""));
+		if (months)
+			snprintf(timebuf + n, sizeof(timebuf) - n,
+				 ", %lu month%s ago",
+				 months, (months > 1 ? "s" : ""));
+		else
+			snprintf(timebuf + n, sizeof(timebuf) - n,
+				 " ago");
+		return timebuf;
+	}
+	/* Otherwise, just years. Centuries is probably overkill. */
+	snprintf(timebuf, sizeof(timebuf), "%lu years ago", (diff + 183) / 365);
+	return timebuf;
+
+}
+
 const char *show_date(unsigned long time, int tz, enum date_mode mode)
 {
 	struct tm *tm;
@@ -95,63 +156,9 @@ const char *show_date(unsigned long time, int tz, enum date_mode mode)
 	}
 
 	if (mode == DATE_RELATIVE) {
-		unsigned long diff;
 		struct timeval now;
 		gettimeofday(&now, NULL);
-		if (now.tv_sec < time)
-			return "in the future";
-		diff = now.tv_sec - time;
-		if (diff < 90) {
-			snprintf(timebuf, sizeof(timebuf), "%lu seconds ago", diff);
-			return timebuf;
-		}
-		/* Turn it into minutes */
-		diff = (diff + 30) / 60;
-		if (diff < 90) {
-			snprintf(timebuf, sizeof(timebuf), "%lu minutes ago", diff);
-			return timebuf;
-		}
-		/* Turn it into hours */
-		diff = (diff + 30) / 60;
-		if (diff < 36) {
-			snprintf(timebuf, sizeof(timebuf), "%lu hours ago", diff);
-			return timebuf;
-		}
-		/* We deal with number of days from here on */
-		diff = (diff + 12) / 24;
-		if (diff < 14) {
-			snprintf(timebuf, sizeof(timebuf), "%lu days ago", diff);
-			return timebuf;
-		}
-		/* Say weeks for the past 10 weeks or so */
-		if (diff < 70) {
-			snprintf(timebuf, sizeof(timebuf), "%lu weeks ago", (diff + 3) / 7);
-			return timebuf;
-		}
-		/* Say months for the past 12 months or so */
-		if (diff < 360) {
-			snprintf(timebuf, sizeof(timebuf), "%lu months ago", (diff + 15) / 30);
-			return timebuf;
-		}
-		/* Give years and months for 5 years or so */
-		if (diff < 1825) {
-			unsigned long years = (diff + 183) / 365;
-			unsigned long months = (diff % 365 + 15) / 30;
-			int n;
-			n = snprintf(timebuf, sizeof(timebuf), "%lu year%s",
-					years, (years > 1 ? "s" : ""));
-			if (months)
-				snprintf(timebuf + n, sizeof(timebuf) - n,
-					", %lu month%s ago",
-					months, (months > 1 ? "s" : ""));
-			else
-				snprintf(timebuf + n, sizeof(timebuf) - n,
-					" ago");
-			return timebuf;
-		}
-		/* Otherwise, just years. Centuries is probably overkill. */
-		snprintf(timebuf, sizeof(timebuf), "%lu years ago", (diff + 183) / 365);
-		return timebuf;
+		return show_date_relative(time, tz, &now);
 	}
 
 	if (mode == DATE_LOCAL)
@@ -866,19 +873,17 @@ static const char *approxidate_digit(const char *date, struct tm *tm, int *num)
 	return end;
 }
 
-unsigned long approxidate(const char *date)
+unsigned long approxidate_relative(const char *date, const struct timeval *tv)
 {
 	int number = 0;
 	struct tm tm, now;
-	struct timeval tv;
 	time_t time_sec;
 	char buffer[50];
 
 	if (parse_date(date, buffer, sizeof(buffer)) > 0)
 		return strtoul(buffer, NULL, 10);
 
-	gettimeofday(&tv, NULL);
-	time_sec = tv.tv_sec;
+	time_sec = tv->tv_sec;
 	localtime_r(&time_sec, &tm);
 	now = tm;
 	for (;;) {
@@ -899,3 +904,10 @@ unsigned long approxidate(const char *date)
 		tm.tm_year--;
 	return mktime(&tm);
 }
+
+unsigned long approxidate(const char *date)
+{
+	struct timeval tv;
+	gettimeofday(&tv, NULL);
+	return approxidate_relative(date, &tv);
+}

-- 
1.6.4.1.261.gf9874
Previous: Nicolas PitreNext: Jeff King
Message 20 of 47 in “Round-down years in "years+months" relative date view”
  1. Round-down years in "years+months" relative date viewDavid Reiss, Aug 27, 2009
  2. Jeff KingAug 28, 2009
  3. Alex RiesenAug 28, 2009
  4. Jeff KingAug 28, 2009
  5. Alex RiesenAug 28, 2009
  6. Jeff KingAug 28, 2009
  7. Alex RiesenAug 28, 2009
  8. A Large Angry SCMAug 28, 2009
  9. Nicolas PitreAug 28, 2009
  10. Jeff KingAug 28, 2009
  11. Alex RiesenAug 28, 2009
  12. Jeff KingAug 28, 2009
  13. Alex RiesenAug 28, 2009
  14. Alex RiesenAug 28, 2009
  15. Nicolas PitreAug 28, 2009
  16. Alex RiesenAug 28, 2009
  17. Nicolas PitreAug 28, 2009
  18. Alex RiesenAug 28, 2009
  19. Nicolas PitreAug 28, 2009
  20. Alex RiesenAug 28, 2009
  21. Jeff KingAug 28, 2009
  22. Alex RiesenAug 28, 2009
  23. Alex RiesenAug 28, 2009
  24. Allow testing of _relative family of time formatting and parsing functionsAlex Riesen, Aug 28, 2009
  25. Alex RiesenAug 28, 2009
  26. Junio C HamanoAug 29, 2009
  27. Alex RiesenAug 30, 2009
  28. Jeff KingAug 30, 2009
  29. Alex RiesenAug 30, 2009
  30. 1/2 Add date formatting and parsing functions relative to a given timeAlex Riesen, Aug 30, 2009
  31. 2/2 Allow testing of _relative family of time formatting and parsing functionsAlex Riesen, Aug 30, 2009
  32. Jeff KingAug 30, 2009
  33. Jeff KingAug 30, 2009
  34. Alex RiesenAug 30, 2009
  35. Jeff KingAug 30, 2009
  36. Alex RiesenAug 30, 2009
  37. 1/3 Add date formatting and parsing functions relative to a given timeJeff King, Aug 30, 2009
  38. Jeff KingAug 30, 2009
  39. Jeff KingAug 31, 2009
  40. 1/4 Add date formatting and parsing functions relative to a given timeJeff King, Aug 31, 2009
  41. Alex RiesenAug 31, 2009
  42. 2/4 refactor test-date interfaceJeff King, Aug 31, 2009
  43. 3/4 tests: add date printing and parsing testsJeff King, Aug 31, 2009
  44. Jeff KingSep 1, 2009
  45. 4/4 fix approxidate parsing of relative months and yearsJeff King, Aug 31, 2009
  46. 2/3 refactor test-date interfaceJeff King, Aug 30, 2009
  47. 3/3 tests: add date printing and parsing testsJeff King, Aug 30, 2009

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