&start behavior doesn't make sense

90 Posts

myfriendscallmebill Reply #1, 19 years, 6 months ago

I’m running Ditto 2.0.1 on MODx 0.9.6RC2. I created ten documents as children of doc ID 48, and gave them pagetitles of "1" to "10".

When I make the following Ditto call, all 10 docs are listed in reverse chronological order, as expected:
[!Ditto? &parents=`48` &display=`all`!]

And when I add pagination I get the same list plus the appropriate pagination placeholders are filled in:
[!Ditto? &parents=`48` &display=`all` &paginate=`1`!]

But when I add &start, things get odd. For example, if I make the following call:
[!Ditto? &parents=`48` &display=`all` &paginate=`1` &start=`3`!]

Then the displayed list only includes documents 4 through 7. In other words, the number of items I specify in &start are chopped off both the top and the bottom of the list. On the other hand, as I try various values for &start, the pagination placeholders such as [+start+], [+stop+], and [+total+] have the values I expect (given that I expect items only to be chopped off the top of the list).

Is this the expected behavoir, or should I file this as a bug?

MODX Staff
12,272 Posts

Ryan Thrash Reply #2, 19 years, 6 months ago

Quote from: myfriendscallmebill at Mar 27, 2007, 02:51 PM

But when I add &start, things get odd. For example, if I make the following call:
[!Ditto? &parents=`48` &display=`all` &paginate=`1` &start=`3`!]

Then the displayed list only includes documents 4 through 7. In other words, the number of items I specify in &start are chopped off both the top and the bottom of the list. On the other hand, as I try various values for &start, the pagination placeholders such as [+start+], [+stop+], and [+total+] have the values I expect (given that I expect items only to be chopped off the top of the list).

Is this the expected behavoir, or should I file this as a bug?

I think I’d file that one as a bug. I would expect to see 4-10 displayed... :/

Ryan Thrash, MODX Co-Founder
Follow me on Twitter at @rthrash or catch my occasional unofficial thoughts at thrash.me

90 Posts

myfriendscallmebill Reply #3, 19 years, 6 months ago

bug filed.

3,250 Posts

MARKSVIRTUALDESK Reply #4, 19 years, 6 months ago

1. Pagination with &display=`all` doesn’t make sense. The two are opposites.
2. Pagination with &start=`3` and &display=`3` does cause issues exactly as you describe. I believe I’ve fixed them in the development version. Please download a copy from my signerature and try it.

90 Posts

myfriendscallmebill Reply #5, 19 years, 6 months ago

Quote from: Mark at Mar 27, 2007, 06:53 PM

Please download a copy from my signature and try it.

Mark:

(1) SETUP
I installed Ditto r1403 under MODx 0.9.6-RC2.
I created a parent document at ID=62.
I created ten child documents, titled "1" to "10".

(2) TEST-1
This Ditto call produces the expected results:
[!Ditto_r1403? &ditto_base=`assets/snippets/ditto_r1403/` &parents=`62` &display=`5` &paginate=`1` &debug=`1` !]

(3) TEST-2
Adding an acsending sort to test 1 produces the expected result on page 1, but on page 2 the list is empty, even though the paging placeholders say that items 6 through 10 are being displayed. Here’s the call:
[!Ditto_r1403? &ditto_base=`assets/snippets/ditto_r1403/` &parents=`62` &display=`5` &paginate=`1` &sortDir=`ASC` &debug=`1` !]

(4) TEST-3
Adding @start to test 1 causes items to be cut from the BOTTOM of the list. E.g. @start=`2` will cause documents "10" to "6" to be displayed on page 1, and documents "5" to "3" to be displayed on page 2. Isn’t @start supposed to cut from the TOP of the list? Here’s the call:
[!Ditto_r1403? &ditto_base=`assets/snippets/ditto_r1403/` &parents=`62` &display=`5` &paginate=`1` &start=`2` &debug=`1` !]

Debug files attached.

What do you think?

3,250 Posts

MARKSVIRTUALDESK Reply #6, 19 years, 6 months ago

Ok, made another commit that should fix this.

Here is the diff since its only a few lines:

Index: trunk/snippet.ditto.php
===================================================================
--- trunk/snippet.ditto.php (revision 1403)
+++ trunk/snippet.ditto.php (revision 1404)
@@ -894,12 +894,12 @@
 	switch($sortDir) {
 		case "DESC":
-			$start = $start;
-			$stop = $stop + $start; 
+			$stop += $start; 
 		break;
 		case "ASC":
-			$start = $start - $offset;
-			$stop = $stop;
+			$start += $offset;
+			$stop += $start;
 		break;
 	}
+
 	if ($ditto->prefetch !== false) {
 		$documentIDs = array_slice($documentIDs,$start,$stop);

90 Posts

myfriendscallmebill Reply #7, 19 years, 6 months ago

Quote from: Mark at Mar 28, 2007, 12:54 AM

Ok, made another commit that should fix this.

Mark:

(1) SETUP
o I installed Ditto r1404 under MODx 0.9.6-RC2.
o I duplicated my previous test parent (to ID=74) with it’s 10 children titled "1" to "10".
o I manually edited the unpub_date of each child to make them sequentially 1 second apart.

(2) TEST-1
With this Ditto call the documents sort correctly, and the pagination placeholders update correctly, but 5 items are displayed on each page, rather than 5 on the first and 3 on the second:
[!Ditto_r1403? &ditto_base=`assets/snippets/ditto_r1404/` &parents=`74` &display=`5` &paginate=`1` &start=`2` &sortDir=`DESC` &debug=`1` &sortBy=`unpub_date` !]

(3) TEST-2
If I simply change the above call to have an ascending sort then: The first page shows items 9 then 10 (while the paging placholders say Ditto’s showing items 1 to 5 of eight), and the second page shows items 4, 5, and 6 (while the paging placholders say Ditto’s showing items 6 to 8 of eight). Here’s the call:
[!Ditto_r1403? &ditto_base=`assets/snippets/ditto_r1404/` &parents=`74` &display=`5` &paginate=`1` &start=`2` &sortDir=`ASC` &debug=`1` &sortBy=`unpub_date` !]

Debug files attached.

3,250 Posts

MARKSVIRTUALDESK Reply #8, 19 years, 6 months ago

Ok, this should fix that. Its been commited as rev 1405.

Index: trunk/snippet.ditto.php
===================================================================
--- trunk/snippet.ditto.php (revision 1404)
+++ trunk/snippet.ditto.php (revision 1405)
@@ -894,5 +894,5 @@
 	switch($sortDir) {
 		case "DESC":
-			$stop += $start; 
+			$stop = ($ditto->prefetch === false) ? $stop + $start : $stop; 
 		break;
 		case "ASC":

Just wanted to say thanks for the detailed test cases! They make finding the problematic code so much quicker!

90 Posts

myfriendscallmebill Reply #9, 19 years, 6 months ago

Quote from: Mark at Mar 28, 2007, 12:41 PM

Ok, this should fix that. Its been commited as rev 1405.

Ok, everything works correctly now except possibly this one thing: &start always trims the OLDEST items from the list. I had thought it was supposed to trim the FIRST items from the list, which would change depending upon how the list was sorted. I also wonder what would happen if I was sorting by an alphanumeric field: would &start still trim the oldest items, and would that make random items disappear from the middle of the list...?

Anyway, thanks for all your great work!

Quote from: Mark at Mar 28, 2007, 12:41 PM

IJust wanted to say thanks for the detailed test cases! They make finding the problematic code so much quicker!

Your welcome, my pleasure

3,250 Posts

MARKSVIRTUALDESK Reply #10, 19 years, 6 months ago

Drat, your right that is backwards... Fixed in 1406.

Index: trunk/snippet.ditto.php
===================================================================
--- trunk/snippet.ditto.php (revision 1405)
+++ trunk/snippet.ditto.php (revision 1406)
@@ -894,5 +894,6 @@
 	switch($sortDir) {
 		case "DESC":
-			$stop = ($ditto->prefetch === false) ? $stop + $start : $stop; 
+			$stop = ($ditto->prefetch === false) ? $stop + $start + $offset : $stop + $offset; 
+			$start += $offset;
 		break;
 		case "ASC":