rhg: Port Python’s `ui.configlist` as `Config::get_list` This new method is not used yet outside of its own unit tests, so this changeset should make no observable change. The Rust parser implementation attempts to exactly replicate the behavior of the Python one, even in edge cases where that behavior is… surprising. New unit tests capture some of these edge cases. This started as a line-by-line port. The main changes are: * Pass around a parser mode enum instead of parser functions * Inline the whole parser into one function * Use `[u8]::get` which returns an `Option`, instead of indexing after explicitly checking the length. Differential Revision: https://phab.mercurial-scm.org/D11389

rust: Generalize the `trim_end_newlines` utility of byte strings … into `trim_end_matches` that takes a callack. Also add `trim_start_matches`. Differential Revision: https://phab.mercurial-scm.org/D11388

dirstate-item: move the C implementation to the same logic Now that we know were we are going, we can update the C implementation. Differential Revision: https://phab.mercurial-scm.org/D11387

dirstate-item: introduce low level C function Since a lot of logic is about to change, we need to isolate it into bits that are easy reusable in the rest of the C code. Especially we need to split the part that do the pure logic from the part that do the Python wrapping. Differential Revision: https://phab.mercurial-scm.org/D11386

dirstate-item: factor some code in the C implementation We have both `dirstate_item_from_v1_meth`, a class method, and `dirstate_item_from_v1_data`, a function taking low level C argument. Lets implement the former with the later. Differential Revision: https://phab.mercurial-scm.org/D11385

dirstate-item: `dirstate_item_from_v1_data` replaces make_dirstate_item For different format, we will need multiple capsule anyways. Differential Revision: https://phab.mercurial-scm.org/D11384

pathutil: replace the `skip` argument of `dirs` with a boolean It is ever only used for `r` file. So we make it a boolean this will give use more versatility later as we will stop storing the state explicitly. Differential Revision: https://phab.mercurial-scm.org/D11383

dirstate: clarify the message in nonnormal checking The previous message was quite verbose and hard to understand. The new one should be friendlier. Differential Revision: https://phab.mercurial-scm.org/D11382

merge: with stable

narrow: fix commits of empty files The problem is that when committing a new file with empty contents (or in general empty file with filelog p1 = -1), hg commit with narrow doesn't create a filelog revision at all, which causes failures in further commands. The problem seems to be that: - hg thinks that instead of creating a new filelog revision, it can use the filelog's p1 (the nullrev) - because it thinks the file contents is the same in that revision and in p1 - because `narrowfilelog.cmp(nullrev, b'')` is True (unlike with `filelog.cmp`) It's not clear to me which `cmp` behaves better. But I think it makes sense to change the commit code to not to "reuse" the null rev when adding an empty file with filelog p1 == filelog p2 == -1. This is consistent with never writing the null rev in the manifest, which `hg verify` claims is an invariant: ``` inside/c@4: manifest refers to unknown revision 000000000000 ``` Differential Revision: https://phab.mercurial-scm.org/D11400