Merge branch 'jc/cutoff-config'

"[gc] rerereResolved = 5.days" used to be invalid, as the variable
is defined to take an integer counting the number of days.  It now
is allowed.

* jc/cutoff-config:
  rerere: allow approxidate in gc.rerereResolved/gc.rerereUnresolved
  rerere: represent time duration in timestamp_t internally
  t4200: parameterize "rerere gc" custom expiry test
  t4200: gather "rerere gc" together
  t4200: make "rerere gc" test more robust
  t4200: give us a clean slate after "rerere gc" tests

Documentation/config.txt

@@ -1564,11 +1564,13 @@ gc.<pattern>.reflogExpireUnreachable::
 gc.rerereResolved::
 	Records of conflicted merge you resolved earlier are
 	kept for this many days when 'git rerere gc' is run.
+	You can also use more human-readable "1.month.ago", etc.
 	The default is 60 days.  See linkgit:git-rerere[1].
 
 gc.rerereUnresolved::
 	Records of conflicted merge you have not resolved are
 	kept for this many days when 'git rerere gc' is run.
+	You can also use more human-readable "1.month.ago", etc.
 	The default is 15 days.  See linkgit:git-rerere[1].
 
 gitcvs.commitMsgAnnotation::

config.c

@@ -2094,6 +2094,28 @@ int git_config_get_expiry(const char *key, const char **output)
 	return ret;
 }
 
+int git_config_get_expiry_in_days(const char *key, timestamp_t *expiry, timestamp_t now)
+{
+	char *expiry_string;
+	intmax_t days;
+	timestamp_t when;
+
+	if (git_config_get_string(key, &expiry_string))
+		return 1; /* no such thing */
+
+	if (git_parse_signed(expiry_string, &days, maximum_signed_value_of_type(int))) {
+		const int scale = 86400;
+		*expiry = now - days * scale;
+		return 0;
+	}
+
+	if (!parse_expiry_date(expiry_string, &when)) {
+		*expiry = when;
+		return 0;
+	}
+	return -1; /* thing exists but cannot be parsed */
+}
+
 int git_config_get_untracked_cache(void)
 {
 	int val = -1;

config.h

@@ -215,6 +215,9 @@ extern int git_config_get_max_percent_split_change(void);
 /* This dies if the configured or default date is in the future */
 extern int git_config_get_expiry(const char *key, const char **output);
 
+/* parse either "this many days" integer, or "5.days.ago" approxidate */
+extern int git_config_get_expiry_in_days(const char *key, timestamp_t *, timestamp_t now);
+
 struct key_value_info {
 	const char *filename;
 	int linenr;

rerere.c

@@ -1133,14 +1133,14 @@ int rerere_forget(struct pathspec *pathspec)
  * Garbage collection support
  */
 
-static time_t rerere_created_at(struct rerere_id *id)
+static timestamp_t rerere_created_at(struct rerere_id *id)
 {
 	struct stat st;
 
 	return stat(rerere_path(id, "preimage"), &st) ? (time_t) 0 : st.st_mtime;
 }
 
-static time_t rerere_last_used_at(struct rerere_id *id)
+static timestamp_t rerere_last_used_at(struct rerere_id *id)
 {
 	struct stat st;
 
@@ -1157,11 +1157,11 @@ static void unlink_rr_item(struct rerere_id *id)
 	id->collection->status[id->variant] = 0;
 }
 
-static void prune_one(struct rerere_id *id, time_t now,
-		      int cutoff_resolve, int cutoff_noresolve)
+static void prune_one(struct rerere_id *id,
+		      timestamp_t cutoff_resolve, timestamp_t cutoff_noresolve)
 {
-	time_t then;
-	int cutoff;
+	timestamp_t then;
+	timestamp_t cutoff;
 
 	then = rerere_last_used_at(id);
 	if (then)
@@ -1172,7 +1172,7 @@ static void prune_one(struct rerere_id *id, time_t now,
 			return;
 		cutoff = cutoff_noresolve;
 	}
-	if (then < now - cutoff * 86400)
+	if (then < cutoff)
 		unlink_rr_item(id);
 }
 
@@ -1182,15 +1182,15 @@ void rerere_gc(struct string_list *rr)
 	DIR *dir;
 	struct dirent *e;
 	int i;
-	time_t now = time(NULL);
-	int cutoff_noresolve = 15;
-	int cutoff_resolve = 60;
+	timestamp_t now = time(NULL);
+	timestamp_t cutoff_noresolve = now - 15 * 86400;
+	timestamp_t cutoff_resolve = now - 60 * 86400;
 
 	if (setup_rerere(rr, 0) < 0)
 		return;
 
-	git_config_get_int("gc.rerereresolved", &cutoff_resolve);
-	git_config_get_int("gc.rerereunresolved", &cutoff_noresolve);
+	git_config_get_expiry_in_days("gc.rerereresolved", &cutoff_resolve, now);
+	git_config_get_expiry_in_days("gc.rerereunresolved", &cutoff_noresolve, now);
 	git_config(git_default_config, NULL);
 	dir = opendir(git_path("rr-cache"));
 	if (!dir)
@@ -1211,7 +1211,7 @@ void rerere_gc(struct string_list *rr)
 		for (id.variant = 0, id.collection = rr_dir;
 		     id.variant < id.collection->status_nr;
 		     id.variant++) {
-			prune_one(&id, now, cutoff_resolve, cutoff_noresolve);
+			prune_one(&id, cutoff_resolve, cutoff_noresolve);
 			if (id.collection->status[id.variant])
 				now_empty = 0;
 		}

t/t4200-rerere.sh

@@ -239,6 +239,43 @@ test_expect_success 'old records rest in peace' '
 	! test -f $rr2/preimage
 '
 
+rerere_gc_custom_expiry_test () {
+	five_days="$1" right_now="$2"
+	test_expect_success "rerere gc with custom expiry ($five_days, $right_now)" '
+		rm -fr .git/rr-cache &&
+		rr=.git/rr-cache/$_z40 &&
+		mkdir -p "$rr" &&
+		>"$rr/preimage" &&
+		>"$rr/postimage" &&
+
+		two_days_ago=$((-2*86400)) &&
+		test-chmtime =$two_days_ago "$rr/preimage" &&
+		test-chmtime =$two_days_ago "$rr/postimage" &&
+
+		find .git/rr-cache -type f | sort >original &&
+
+		git -c "gc.rerereresolved=$five_days" \
+		    -c "gc.rerereunresolved=$five_days" rerere gc &&
+		find .git/rr-cache -type f | sort >actual &&
+		test_cmp original actual &&
+
+		git -c "gc.rerereresolved=$five_days" \
+		    -c "gc.rerereunresolved=$right_now" rerere gc &&
+		find .git/rr-cache -type f | sort >actual &&
+		test_cmp original actual &&
+
+		git -c "gc.rerereresolved=$right_now" \
+		    -c "gc.rerereunresolved=$right_now" rerere gc &&
+		find .git/rr-cache -type f | sort >actual &&
+		>expect &&
+		test_cmp expect actual
+	'
+}
+
+rerere_gc_custom_expiry_test 5 0
+
+rerere_gc_custom_expiry_test 5.days.ago now
+
 test_expect_success 'setup: file2 added differently in two branches' '
 	git reset --hard &&
 
@@ -419,24 +456,6 @@ count_pre_post () {
 	test_line_count = "$2" actual
 }
 
-test_expect_success 'rerere gc' '
-	find .git/rr-cache -type f >original &&
-	xargs test-chmtime -172800 <original &&
-
-	git -c gc.rerereresolved=5 -c gc.rerereunresolved=5 rerere gc &&
-	find .git/rr-cache -type f >actual &&
-	test_cmp original actual &&
-
-	git -c gc.rerereresolved=5 -c gc.rerereunresolved=0 rerere gc &&
-	find .git/rr-cache -type f >actual &&
-	test_cmp original actual &&
-
-	git -c gc.rerereresolved=0 -c gc.rerereunresolved=0 rerere gc &&
-	find .git/rr-cache -type f >actual &&
-	>expect &&
-	test_cmp expect actual
-'
-
 merge_conflict_resolve () {
 	git reset --hard &&
 	test_must_fail git merge six.1 &&
@@ -446,6 +465,8 @@ merge_conflict_resolve () {
 }
 
 test_expect_success 'multiple identical conflicts' '
+	rm -fr .git/rr-cache &&
+	mkdir .git/rr-cache &&
 	git reset --hard &&
 
 	test_seq 1 6 >early &&