repoview: add caching bits Add a caching infrastructure to cache hidden changesets. The cache tries to read the cache lazily and falls back to recomputing if no wlock can be obtain. To validate the cache we store a sha of the obstore content and repo heads in the beginning of the cache which we check every request.

repoview: split _gethiddenblockers Split up _gethiddenblockers into two categories: (1) "static' blockers that solely rely on the contents of obstore and are visible children of hidden changsets. (2) "dynamic" blockers, appearing by having wd parents, bookmarks or tags pointing to hidden changesets. We assume that (1) doesn't change often and can be easily cached with a good invalidation strategy. (2) change often, but barely produce blockers, so we can recompute them if necessary.

repoview: use set for blockers Blockers should be unique but tags and bookmarks could point to the same rev, therefore use a set to ensure that we don't have duplicates.

histedit: preserve initial author on fold (issue4296) When the authorship of the changeset folded in does not match that of the base changeset, we currently use the configured ui.username instead. This is especially surprising when the user is not the author of either of the changesets. In such cases, the resulting authorship (the user's) is clearly incorrect. Even when the user is folding in a patch they authored themselves, it's not clear whether they should take over the authorship. Let's instead keep it simple and always preserve the base changeset's authorship. This is also how "git rebase -i" handles folding/squashing.

run-tests: fix some io ordering backported from default

merge with stable

test-revert: add case where file is tracked but deleted in working directory

test-revert: add case with untracked files with unique content This test highlights similar misbehavior as its parent changesets.

test-revert: add case with untracked files with reverted content This test highlights similar misbehaviors as its parent changesets.

test-revert: add case where file exists but is untracked in working directory This test highlights a small misbehavior in output when reverting to another revision not including the untracked file.

test-revert: add case where the file is marked as removed in the wc Unlike untracked, the file is also missing from the working directory. This test highlights a small misbehavior in output when reverting to another revision.

test-revert: add case where wc content is different from "base" and "parent" This test highlights a case where backups are not created and the user may lose data.

test-revert: add case where wc content is already reverted to base content This test highlights multiple misbehaviors of revert. We augment the test comments accordingly.

test-revert: add case where file exists neither in "base" nor in "parent"

test-revert: add case where the file is removed between "base" and "parent"

test-revert: add case where file is unchanged between "base" and "parent" This test highlights a minor misbehavior in the message displayed during an explicit revert with a target revision.

test-run-tests: fix stdout/stderr io ordering

test-revert: add case where file is added between "base" and "parent"

merge with stable

test-revert: add methodical revert to "base" with explicit file path We now also test reverting file to another revision's content. However this differs from previously introduced test by using the explicit path of each "case file" when calling revert. This should result in the same result regarding file content and backup creation, but the output of the `hg revert` call should differ.

test-revert: add methodical revert with explicit file path We now also test reverting file to the working directory parent content. However this differs from the previously introduced test by using the explicit path of each "case file" when calling revert. This should result in the same result regarding file content and backup creation, but the output of the `hg revert` call should differ.

test-revert: add methodical revert to "base" We now also test reverting s file to the content of another revision. This is still done using the `--all` flag.

test-revert: add methodical revert to parent for working directory Now that we can automatically generate states, we need to actually run revert on them and check the result. While running such tests we are checking multiple elements. The output of the `hg revert` command, the resulting content of file, and the creation of backup file. The first practical test is using the simple case `hg revert --all`, reverting all files to working directory parent content.

test-revert: display the list of all generated cases This will help to track all existing cases. (still very simple now)