PDE API builder runs even no changes happen on the project

[iloveeclipse]

As a side effect of many more builds triggered due PDE change #2218 (see #2233) the API build takes much longer time to complete as usually. I haven't checked the code, but it seems it doesn't maintain any build state and simply re-runs full analysis on the bundle if triggered by the autobuild, even if the bundle itself isn't changed.

If I'm not mistaken, there is no need to run API checks if dependencies are changed, so ideally API builder should don't do anything, it should only run if something inside the bundle is changed.

[merks]

there is no need to run API checks if dependencies are changed

There are things like @noreference, @noextend, @noimplement, @noinstantiate, @nooverride that can definitely change upstream...

[iloveeclipse]

there is no need to run API checks if dependencies are changed

There are things like @noreference, @noextend, @noimplement, @noinstantiate, @nooverride that can definitely change upstream...

Shouldn't these be breaking changes? Something that was API is now declared as non-API?

[iloveeclipse]

OK, let assume someone removes the tags by mistake, the errors should be shown :-(

Other possibility would be to restrict checks by looking at the delta - if it contains projects that are not direct dependencies of the current bundle, we could skip the API checks? I assume if we extend some class/interface, it must be direct dependency?

[iloveeclipse]

Or we can check for dependencies only on clean build, as compromise, or via preference?
Also if delta is empty (I believe on startup) checks could be skipped.

[merks]

Just a random thought. One might record an API "signature" (digest of some sort) for a project that would capture important externally visible details. Or perhaps some preference for different desired behaviors. Or even a preference to disable automatic checking... Random thoughts....

[laeubi]

If I'm not mistaken, there is no need to run API checks if dependencies are changed

Its really not that simple:

1. bundles can reexport dependencies
2. Classes can extend other classes or implement interface and inherit API from them
3. In case of Extensible-API even fragments can contribute API to a host

so bottom line: Its not trivial ... still it would be beneficial if it could be made more smart - but should be covered by tests given we have spurious API tooling problems already during release.