Add documentation for milestones in Gantt diagram

[digulla]

PR #788 added milestones but the documentation how to use them is still missing.

I looked at the PR and I can't figure out how that feature is supposed to work.

[kut]

I think milestones were added with #788?

[digulla]

Yes. I'll rephrase my ticket :-)

[digulla]

I tried to create an example but the flag "milestone" doesn't seem to have an effect (at least not on the online editor):

gantt
	title A Gantt Diagram
	dateFormat  YYYY-MM-DD
	section Section
	A task           :a1, 2014-01-01, 30d
  M1 :after a1, milestone
  M2 :after a1
	Another task     :after a1  , 20d
	section Another
	Task in sec      :2014-01-12  , 12d
	another task      : 24d
	

[gkTim]

To add a milestone to your diagram add this:

My milestone :milestone, m1, 2020-06-09, 1d

The 1d is necessary so the milestone position is correct.

[obstschale]

hey, I just found this issue. Do you need help documenting it? If I wouldn't have googled milestones for mermaid, I would never have found this gem.

[obstschale]

I am a little bit confused. It seems that the milestone feature is not working properly. Check this out:

I use the gantt chart from the documentation:

gantt
    dateFormat  YYYY-MM-DD
    title       Adding GANTT diagram functionality to mermaid
    excludes    weekends
    %% (`excludes` accepts specific dates in YYYY-MM-DD format, days of the week ("sunday") or "weekends", but not the word "weekdays".)

    section A section
    Milestone                 :milestone, 2014-01-06, 1h
    Completed task            :done,      des1, 2014-01-06,2014-01-08
    Milestone                 :milestone, after des1, 1h
    Active task               :active,    des2, 2014-01-09, 3d
    Future task               :           des3, after des2, 5d
    Milestone                 :milestone, after des3, 1h
    Future task2              :           des4, after des3, 5d

    section Critical tasks
    Completed task in the critical line :crit, done, 2014-01-06,24h
    Implement parser and jison          :crit, done, after des1, 2d
    Create tests for parser             :crit, active, 3d
    Future task in critical line        :crit, 5d
    Create tests for renderer           :2d
    Add to mermaid                      :1d

    section Documentation
    Describe gantt syntax               :active, a1, after des1, 3d
    Add gantt diagram to demo page      :after a1  , 20h
    Add another diagram to demo page    :doc1, after a1  , 48h

    section Last section
    Describe gantt syntax               :after doc1, 3d
    Add gantt diagram to demo page      :20h
    Add another diagram to demo page    :48h

As you can see.

• Number 1: Looks ok
• Number 2: Text not properly positioned
• Number 3: Text and symbol diverge

I think these Issues should be fixed before we add them to the documentation, don't you?

PS: I use 1h as length. Because 1d, as mentioned by @gkTim, will position the milestone after the date. 1h will position it on that date. Try 1w to see what I mean

[vic-t]

@obstschale I just ran the exact same markup on my system, I don't have the issues you mentioned.

[obstschale]

Interessing. Maybe a new version of mermaid fixed it? The mermaid live editor does exactly output your screenshot. But Gitlab and Notable still output the broken version. Unfortunatley, I cannot find out which versions of mermaid these softwares use.

[obstschale]

It seems that a new mermaid version fixed this issue. In GitLab the posted code works. Notable is still not updated.