Calligra/Schedules/3.0/Porting Plan

Dates

• "End of Merge window for master"^ until: Wed March 4th (proposed)
• "Porting start": same day of merge window close

^ To get some patches in that do not fit for the 2.9 branch and otherwise would bitrot due to the Qt5/KF5 port, there will be a merge window for master. Everyone having some WIP stuff that is good enough for merging, brush it up now and get it in!

Patches to merge

Paste links to patches you want in master, so the window won't be closed too early. Remove them after submitting!

jstaniek:

• https://git.reviewboard.kde.org/r/122559/ (almost done, expected: 28th)
• https://git.reviewboard.kde.org/r/122560/ (almost done, expected: 28th)
• https://git.reviewboard.kde.org/r/120940/ (expected: 3rd)

General

• Porting branch named "frameworks" usually, some stuff expects it even.
• Min Qt5 version: 5.2 (matches current KF5 min required version)
• Min KF5 version: 5.?
• Min CMake version: ? (proposal: min required version of used KF5)
• Min ECM version: 1.? (proposal: min required version of used KF5)

Porting Rules

• do not port away from kdelibs4support initally, but see to get it added to the build as quickly as possible (only then go perhaps further)
• ensure CI always manages to build (to ease life of co-porters)
• love the tests
• anything that needs temporarily to be disabled by commenting out should get a tag "QT5TODO" (anything better?), so it will not be forgotton before 3.0

To not have people step on each other toes and do conflicting work there will be a board on todo.kde.org where people can take a product before they start working on making it build. (TODO for Friedrich)

Porting Helpers

• Frameworks 5 porting notes
• Frameworks 5 apidox
• Frameworks 5 build instructions
• Building Calligra is still the same, just with new deps
• kde-dev-scripts.git on git.kde.org has useful porting scripts

On #kde-devel the recommendation was to not blindly run any porting scripts that are available, but rather decide case-by-case if to run the script or just do manual porting. Another reason why splitting the porting work into different people makes more sense.

Porting Targets

Different parts of Calligra will go different miles for 3.0. Some might port away from kdelibs4support as there is not a lot to do, some might be happily using it for 3.0. Both should be very fine. Important are as few regressions as possible and something that is usable :)

Stuff that can be removed

• 3rdparty/kdchart/
• 3rdparty/kdchartpatches/
• 3rdparty/kdgantt/
• 3rdparty/kdganttpatches/
• libs/db/
• libs/koproperty/
• libs/koreport/
• plugins/reporting/

kdchart & kdgantt are to be replaced by kdiagram (kchart,kgantt, ask frinring).

db, koproperty & koreport are to be replaced by predicate, kproperty & kreport (ask jstaniek). Removing these libs/plugins will also render some Find*,cmake macros unneeded, but best check the buildsystem before just removing them.

Stuff to be done before the port

Reformatting

Any reformatting should be ideally done also in 2.9, to easy porting any further bug fixes.

• rename all krita files to the calligra standard. (cc -> cpp, underscore -> CamelCaps)
• from kde-dev-scripts, run:
  • clean-forward-declaration.sh (remove unused forward declarations)
• from plasma-framework, run:
  • port-qslots.sh (to port to Q_SLOTS and Q_SIGNALS)
  • port-includes.sh (to get rid of the module prefixes in includes)
  • port-cmake-style.sh (to get a bit more consistency)
• rest of the scripts at least for pigment and krita (boud)

Under discussion still

• from kde-dev-scripts, run:
  • astyle-kdelibs (prevents the astyle problems with foreach and so on)

Pro:

• clean code

Contra:

• "Applying full astyle is IMHO not OK, and even against efforts of everyone who keeps eye on proper coding style while doing code reviews." (jstaniek)
• "Secondly, breaking git blame is unacceptable. Unlike file renames, there's no equivalent of --follow or ignoring whitespace while patching, it's a massive irreversible break in history." (jstaniek)
  People who try this would have to work with scripts like these git-blame-prior-commits

Not to be done

• replace all header guards with '#pragma once'
  "because errors with header guards are actually quite frequent, and all compilers support this pragma now." (boud)

Reason against: not part of official spec, QtCreator fails on that, not very spread

Prepare architecture/technology changes

• plugin loading. This changed a lot in KF5. We already didn't use the sycoca anymore for loading plugins, and we probably can, for now, still use the .desktop file system to find plugins. However, we should check the old Qt5 porting branch and see if we can re-use its plugin loader. That uses the new Qt5 plugin+json combination already. Check KoJsonTrader.cpp
• That branch also contains some patches for Qt regressions (like bcd822eac52e09b6bf7a4c9fe293c9b3234a6486 or a5361d299b3991f9414466ad9d0c83537e6f2778), so it might be useful to refer to it while porting the libs, Words, Sheets and Stage.

Any takers?

Stuff not to be done for 3.0

Splitting up the repository some more

Initial porting steps

done by 1 person

1. Merge "calligra/2.9" another time into "master"
2. Branch off "frameworks" from "master"
3. Apply https://git.reviewboard.kde.org/r/121541/
4. Remove subdirs of stuff moved outside already
5. Port just the buildsystem to Qt5/KF5/ECM as much as needed to get "cmake" configure pass and "make" && "make install" also pass with success, without porting any code (should be all disabled still by step 3).
6. Create commit and push "frameworks" branch to central Calligra repo
7. Request a build on KDE CI for the "frameworks" branch
8. Take disabled product from end of product dep tree^ and make it build:
   1. remove "UNPORTED" tag
   2. port it as much as needed to make it build
   3. commit to "frameworks" branch
9. if LIB_CALLIGRA has been added to the build, tell everyone to join
   goto 8. until there is no more "UNPORTED" tag

^The dep tree of products can be either seen from content of CalligraProducts.cmake or in a picture by using the generated "product_deps.dot" in the toplevel build dir:

   dot -Tsvg product_deps.dot > product_deps.svg

or

   dot -Tpng product_deps.dot > product_deps.png

Links

• Porting Kexi to Qt 5 / KF 5