Debians commandline package manager https://git.kalnischkies.de/apt/atom?h=main 2026-01-05T21:20:24Z 2026-01-05T21:20:24Z Julian Andres Klode jak@debian.org 2025-12-28T15:56:28Z urn:sha1:21d099878ed8c34f3b13747bcec380e0402e57a3 The previous use of decision here conflicted with the use of decision level and the general notion of having made a decision, because the assignment might have been propagated as a matter of fact. 2025-10-26T07:28:08Z Julian Andres Klode jak@debian.org 2025-10-26T07:24:39Z urn:sha1:5e8e69cdd6b512480f3208298725e1e44c80f06e Not needed so far because we export a default 3.0 APT_SOLVER, but quite useful if we stop doing so (next commit). 2025-03-08T22:18:05Z Julian Andres Klode julian.klode@canonical.com 2025-03-06T19:07:30Z urn:sha1:3967b75ae4a10d0d79560dfecb8eb210aad4f4f2 Introduce a new function, LongWhyStr() that returns a longer reason for why something is being installed (or not). This does the same path walk as the other function does, but it renders the clauses at each level, and one per line, so the whole output is a lot more informative. It is a separate function to keep the existing debug messages use the simple single line implication graph We remove the other special case in AddWork() for empty solutions to mke use of the general case in Solve() instead, and then adapt the case in Solve() to the same case as in Enqueue(). This also happens to fix the bug that when we encountered an empty clause we just printed the clause had no solution, but not how we got to install the package with the clause. Adapt the test suite for the changes which is an annoying amount of paperwork. 2025-02-14T18:08:45Z Julian Andres Klode julian.klode@canonical.com 2025-02-05T19:37:12Z urn:sha1:943562a4ed2ddc80b84466d85e821037937f8b5c Dependencies shared by all versions are enqueued at the package level, so avoid enqueuing duplicates at the version level. This presumably has no meaningful impact on performance, potentially a negative performance impact on some workloads as we now need to find the duplicates again; it can become useful when there is a lot of backtracking. More importantly though this improves error messages, because now we can say that "all versions of foo depend on X", rather than saying "foo=1 depends on X" and you are left wondering why we did not select "foo=2". In this commit though, improved error messages are not implemented, they depend on redesigning the reason tracking to use clauses. Also the rationale tracking includes a lot more dependencies of the form "pkg:arch=version -> pkg:arch" which are annoying. Improved error messages should fold them into one node. 2025-02-14T18:04:56Z Julian Andres Klode julian.klode@canonical.com 2025-02-05T21:06:38Z urn:sha1:9b8aaaa7abbf36d937dbf7160caa2d9c7c92871f We forgot this in the previous iteration. This makes the reasoning in the test cases much nicer and apt-test's mantic-to-noble-jak.edsp now finishes rather than running into the timeout (potentially forever). 2025-02-14T18:04:56Z Julian Andres Klode julian.klode@canonical.com 2025-02-05T20:31:53Z urn:sha1:b8918cb89ada945d92c720446177f1ef5185b5a5 Instead of utilizing the reverse depends functionality of the cache and marking all possible reverse dependencies for removal, mark them ourselves by keeping track of reverse-implication-clauses. Notably, this improves the reverse dependency rejection substantially: The previous RejectReverseDependencies() function did not handle Provides. For this to work correctly right now, we need to discover optional clauses too when queuing them. This is somewhat suboptimal as we technically we don't care if they become unsat, we just waste time tracking them. The tests get a bit awkward, but oh well, we use what we can use. 2025-02-14T18:04:56Z Julian Andres Klode julian.klode@canonical.com 2025-02-05T19:11:35Z urn:sha1:f870bd44522d195199987b0e073d495eed060495 If a dependency can be satisfied by all versions of a package, add the package to the clause instead of the version object. This works only if there are no providers for the package: Providers are quite hard to enumerate over and make sure that all versions of a package satisfy the provider dependency. Implement arbitrary selection between packages and versions for the CompareProviders class: We pick the best version for each package and then pit them against each other. 2025-01-30T13:50:15Z Julian Andres Klode julian.klode@canonical.com 2024-11-02T12:55:39Z urn:sha1:3523efb15d48ce3c6f9212f50dfc892497ba9dcb Instead of directly propagating in a recursive fashion, queue propagations in a queue and work on them in a loop per the miniSAT paper. We call Propagate() only at the end of the FromDepCache() function and then in the Solve loop. Delaying the initial propagation means that we get a stronger reasoning: Assume you have x->a->b->c, y->c and you install x,y: - Previously we traversed: x, y, x->a, a->b, b->c, (y->c) - but now we traverse: x, y, x->a, y->c, a->b, (b->c) Notably c now has the implication y->c instead of x->a->b->c. Inside the solver we need to call Propagate in a loop: Propagating facts can fail and we then backtrack. If backtracking is succesful, we have gained a new fact to propagate. 2024-05-24T15:01:35Z Julian Andres Klode julian.klode@canonical.com 2024-05-19T18:04:47Z urn:sha1:b5997949909ee9d5e9981c8311aea97c7b2620fd Highlights: - test-bug-618848-always-respect-user-requests: (Do not) Support 3.0 solver A manually installed package is never removed just because we request the removal of its dependency in solver3. - test-bug-657695-resolver-breaks-on-virtuals: Support 3.0 solver For manually installed packages, solver 3.0 would require some new xserver-xorg-video-driver to Conflict+Replace+Provides the old one (once the logic is implemented), but that does seem reasonable. - test-bug-720597-build-dep-purge: Support 3.0 solver This needs a simple aptmark auto because pkga is removed by the build-dep. But further adjustments are necessary because it weirdly tested for no autoremovable packages before installing pkgc. - test-bug-960705-*: Support 3.0 solver Bit awkward to deal with; notably the protect to conflict doesn't actually work anymore and that is a feature these days. 2022-09-02T21:37:58Z David Kalnischkies david@kalnischkies.de 2022-09-02T09:07:58Z urn:sha1:e1f332324f81b589561a9d9bce8a55d4895f26ec The command line is evaluated in two steps: First all packages given are marked for install and as a second step the resolver is started on all of them in turn to get their dependencies installed. This is done so a user can provide a non-default choice on the command line and have it respected regardless of where on the command line it appears. On the other hand, the order in which dependencies are resolved can matter, so instead of using a "random" order, we now do this in the order given on the command line, so if you e.g. have a meta package pulling in non-default choices and mention it first the choices are respected predictably instead of depending on first appearance of the package name while creating the binary cache. I might have "broken" this more than a decade ago while introducing the reworked command line parsing for Multi-Arch, which also brought in the split into the two steps mentioned above which was the far more impactful 'respect user choice' change. This one should hardly matter in practice, but as the tests show, order can have surprising side effects.