view tests/test-status-terse.t @ 49000:dd6b67d5c256 stable

rust: fix unsound `OwningDirstateMap`

As per the previous patch, `OwningDirstateMap` is unsound. Self-referential
structs are difficult to implement correctly in Rust since the compiler is
free to move structs around as much as it wants to. They are also very rarely
needed in practice, so the state-of-the-art on how they should be done within
the Rust rules is still a bit new.

The crate `ouroboros` is an attempt at providing a safe way (in the Rust sense)
of declaring self-referential structs. It is getting a lot attention and was
improved very quickly when soundness issues were found in the past: rather than
relying on our own (limited) review circle, we might as well use the de-facto
common crate to fix this problem. This will give us a much better chance of
finding issues should any new ones be discovered as well as the benefit of
fewer `unsafe` APIs of our own.

I was starting to think about how I would present a safe API to the old struct
but soon realized that the callback-based approach was already done in
`ouroboros`, along with a lot more care towards refusing incorrect structs.

In short: we don't return a mutable reference to the `DirstateMap` anymore, we
expect users of its API to pass a `FnOnce` that takes the map as an argument.
This allows our `OwningDirstateMap` to control the input and output lifetimes
of the code that modifies it to prevent such issues.

Changing to `ouroboros` meant changing every API with it, but it is relatively
low churn in the end. It correctly identified the example buggy modification of
`copy_map_insert` outlined in the previous patch as violating the borrow rules.

Differential Revision: https://phab.mercurial-scm.org/D12429

  $ mkdir folder
  $ cd folder
  $ hg init
  $ mkdir x x/l x/m x/n x/l/u x/l/u/a
  $ touch a b x/aa.o x/bb.o
  $ hg status
  ? a
  ? b
  ? x/aa.o
  ? x/bb.o

  $ hg status --terse u
  ? a
  ? b
  ? x/
  $ hg status --terse maudric
  ? a
  ? b
  ? x/
  $ hg status --terse madric
  ? a
  ? b
  ? x/aa.o
  ? x/bb.o
  $ hg status --terse f
  abort: 'f' not recognized
  [10]

Add a .hgignore so that we can also have ignored files

  $ echo ".*\.o" > .hgignore
  $ hg status
  ? .hgignore
  ? a
  ? b
  $ hg status -i
  I x/aa.o
  I x/bb.o

Tersing ignored files
  $ hg status -t i --ignored
  I x/

Adding more files
  $ mkdir y
  $ touch x/aa x/bb y/l y/m y/l.o y/m.o
  $ touch x/l/aa x/m/aa x/n/aa x/l/u/bb x/l/u/a/bb

  $ hg status
  ? .hgignore
  ? a
  ? b
  ? x/aa
  ? x/bb
  ? x/l/aa
  ? x/l/u/a/bb
  ? x/l/u/bb
  ? x/m/aa
  ? x/n/aa
  ? y/l
  ? y/m

  $ hg status --terse u
  ? .hgignore
  ? a
  ? b
  ? x/
  ? y/

Run from subdirectory
  $ hg status --terse u --cwd x/l
  ? .hgignore
  ? a
  ? b
  ? x/
  ? y/
  $ relstatus() {
  >   hg status --terse u --config commands.status.relative=1 "$@";
  > }
This should probably have {"l/", "m/", "n/"} instead of {"."}. They should
probably come after "../y/".
  $ relstatus --cwd x
  ? ../.hgignore
  ? ../a
  ? ../b
  ? .
  ? ../y/
This should probably have {"u/", "../m/", "../n/"} instead of {"../"}.
  $ relstatus --cwd x/l
  ? ../../.hgignore
  ? ../../a
  ? ../../b
  ? ../
  ? ../../y/
This should probably have {"a/", "bb", "../aa", "../../m/", "../../n/"}
instead of {"../../"}.
  $ relstatus --cwd x/l/u
  ? ../../../.hgignore
  ? ../../../a
  ? ../../../b
  ? ../../
  ? ../../../y/
This should probably have {"bb", "../bb", "../../aa", "../../../m/",
"../../../n/"} instead of {"../../../"}.
  $ relstatus --cwd x/l/u/a
  ? ../../../../.hgignore
  ? ../../../../a
  ? ../../../../b
  ? ../../../
  ? ../../../../y/

  $ hg add x/aa x/bb .hgignore
  $ hg status --terse au
  A .hgignore
  A x/aa
  A x/bb
  ? a
  ? b
  ? x/l/
  ? x/m/
  ? x/n/
  ? y/

Including ignored files

  $ hg status --terse aui
  A .hgignore
  A x/aa
  A x/bb
  ? a
  ? b
  ? x/l/
  ? x/m/
  ? x/n/
  ? y/l
  ? y/m
  $ hg status --terse au -i
  I x/aa.o
  I x/bb.o
  I y/l.o
  I y/m.o

Committing some of the files

  $ hg commit x/aa x/bb .hgignore -m "First commit"
  $ hg status
  ? a
  ? b
  ? x/l/aa
  ? x/l/u/a/bb
  ? x/l/u/bb
  ? x/m/aa
  ? x/n/aa
  ? y/l
  ? y/m
  $ hg status --terse mardu
  ? a
  ? b
  ? x/l/
  ? x/m/
  ? x/n/
  ? y/

Modifying already committed files

  $ echo "Hello" >> x/aa
  $ echo "World" >> x/bb
  $ hg status --terse maurdc
  M x/aa
  M x/bb
  ? a
  ? b
  ? x/l/
  ? x/m/
  ? x/n/
  ? y/

Respecting other flags

  $ hg status --terse marduic --all
  M x/aa
  M x/bb
  ? a
  ? b
  ? x/l/
  ? x/m/
  ? x/n/
  ? y/l
  ? y/m
  I x/aa.o
  I x/bb.o
  I y/l.o
  I y/m.o
  C .hgignore
  $ hg status --terse marduic -a
  $ hg status --terse marduic -c
  C .hgignore
  $ hg status --terse marduic -m
  M x/aa
  M x/bb

Passing 'i' in terse value will consider the ignored files while tersing

  $ hg status --terse marduic -u
  ? a
  ? b
  ? x/l/
  ? x/m/
  ? x/n/
  ? y/l
  ? y/m

Omitting 'i' in terse value does not consider ignored files while tersing

  $ hg status --terse marduc -u
  ? a
  ? b
  ? x/l/
  ? x/m/
  ? x/n/
  ? y/

Trying with --rev

  $ hg status --terse marduic --rev 0 --rev 1
  abort: cannot use --terse with --rev
  [10]

Config item to set the default terseness
  $ cat <<EOF >> $HGRCPATH
  > [commands]
  > status.terse = u
  > EOF
  $ hg status -mu
  M x/aa
  M x/bb
  ? a
  ? b
  ? x/l/
  ? x/m/
  ? x/n/
  ? y/

Command line flag overrides the default
  $ hg status --terse=
  M x/aa
  M x/bb
  ? a
  ? b
  ? x/l/aa
  ? x/l/u/a/bb
  ? x/l/u/bb
  ? x/m/aa
  ? x/n/aa
  ? y/l
  ? y/m
  $ hg status --terse=mardu
  M x/aa
  M x/bb
  ? a
  ? b
  ? x/l/
  ? x/m/
  ? x/n/
  ? y/

Specifying --rev should still work, with the terseness disabled.
  $ hg status --rev 0
  M x/aa
  M x/bb
  ? a
  ? b
  ? x/l/aa
  ? x/l/u/a/bb
  ? x/l/u/bb
  ? x/m/aa
  ? x/n/aa
  ? y/l
  ? y/m