revlog: give EXTSTORED flag value to narrowhg Narrowhg has been using "1 << 14" as its revlog flag value for a long time. We (Google) have many repos with that value in production already. When the same value was reserved for EXTSTORED, it made those repos invalid. Upgrading them will be a little painful. We should clearly have reserved the value for narrowhg a long time ago. Since the EXTSTORED flag is not yet in any release and Facebook also says they have not started using it in production, so it should be okay to change it. This patch gives the current value (1 << 14) back to narrowhg and gives a new value (1 << 13) to EXTSTORED.

help: don't let tools reflow revlog flags list Before this change, the text about revlog flags was reflowed into a single paragraph, which made it a bit hard to read. I don't even know the rules around this, but adding a blank line before each flag seems to prevent the reflowing.

help: format revlog.txt more closely to result The rendered text has spaces before each item in the list

hgweb: simplify calculation of first revision in filelog command

hgweb: restore ascending iteration on revs in filelog web command Follow-up on 96f811bceb85. Adjust back the "parity" generator's offset to keep rendering the same.

context: extract _changesinrange() out of blockancestors() We'll need it to write a blockdescendants function in next changeset.

shelve: allow multiple shelves with --patch and --stat Before this patch, there was a single way to see multiple shelves using `--patch --list` which show all the shelves. Doing `--patch s1 s2` returns an error. This patch allows to show multiple shelves using `--patch` and `--stat`.

zstd: vendor python-zstandard 0.6.0 Commit 63c68d6f5fc8de4afd9bde81b13b537beb4e47e8 from https://github.com/indygreg/python-zstandard is imported without modifications (other than removing unwanted files). This includes minor performance and feature improvements. It also changes the vendored zstd library from 1.1.1 to 1.1.2. # no-check-commit

util: add length argument to util.buffer() util.buffer() either returns inbuilt buffer function or defines a new one which slices. The inbuilt buffer() also has a length argument which is missing from the ones we defined. This patch adds that length argument.

py3: replace pycompat.getenv with encoding.environ.get pycompat.getenv returns os.getenvb on py3 which is not available on Windows. This patch replaces them with encoding.environ.get and checks to ensure no new instances of os.getenv or os.setenv are introduced.