view tests/test-origbackup-conflict.t @ 50762:c51b178b0b7e

configitems: declare items in a TOML file

Mercurial ships with Rust code that also needs to read from the config.
Having a way of presenting `configitems` to both Python and Rust is needed
to prevent duplication, drift, and have the appropriate devel warnings.

Abstracting away from Python means choosing a config format. No single format
is perfect, and I have yet to come across a developer that doesn't hate all of
them in some way.
Since we have a strict no-dependencies policy for Mercurial, we either need
to use whatever comes with Python, vendor a library, or implement a custom
format ourselves.

Python stdlib means using JSON, which doesn't support comments and isn't great
for humans, or `configparser` which is an obscure, untyped format that nobody
uses and doesn't have a commonplace Rust parser.
Implementing a custom format is error-prone, tedious and subject to the
same issues as picking an existing format.

Vendoring opens us to the vast array of common config formats. The ones
being picked for most modern software are YAML and TOML. YAML is older and
common in the Python community, but TOML is much simpler and less error-prone.
I would much rather be responsible for the <1000 lines of `tomli`, on top of
TOML being the choice of the Rust community, with robust crates for reading it.

The structure of `configitems.toml` is explained inline.

Set up repo

  $ cat << EOF >> $HGRCPATH
  > [ui]
  > origbackuppath=.hg/origbackups
  > [merge]
  > checkunknown=warn
  > EOF
  $ hg init repo
  $ cd repo
  $ echo base > base
  $ hg add base
  $ hg commit -m "base"

Make a dir named b that contains a file, and a file named d

  $ mkdir -p b
  $ echo c1 > b/c
  $ echo d1 > d
  $ hg add b/c d
  $ hg commit -m "c1"
  $ hg bookmark c1

Peform an update that causes b/c to be backed up

  $ hg up -q 0
  $ mkdir -p b
  $ echo c2 > b/c
  $ hg up --verbose c1
  resolving manifests
  b/c: replacing untracked file
  getting b/c
  creating directory: $TESTTMP/repo/.hg/origbackups/b
  getting d
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (activating bookmark c1)
  $ test -f .hg/origbackups/b/c

Make files named b and d

  $ hg up -q 0
  $ echo b1 > b
  $ echo d2 > d
  $ hg add b d
  $ hg commit -m b1
  created new head
  $ hg bookmark b1

Perform an update that causes b to be backed up - it should replace the backup b dir

  $ hg up -q 0
  $ echo b2 > b
  $ hg up --verbose b1
  resolving manifests
  b: replacing untracked file
  getting b
  removing conflicting directory: $TESTTMP/repo/.hg/origbackups/b
  getting d
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (activating bookmark b1)
  $ test -f .hg/origbackups/b

Perform an update the causes b/c to be backed up again - it should replace the backup b file

  $ hg up -q 0
  $ mkdir b
  $ echo c3 > b/c
  $ hg up --verbose c1
  resolving manifests
  b/c: replacing untracked file
  getting b/c
  creating directory: $TESTTMP/repo/.hg/origbackups/b
  removing conflicting file: $TESTTMP/repo/.hg/origbackups/b
  getting d
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (activating bookmark c1)
  $ test -d .hg/origbackups/b

Cause two symlinks to be backed up that points to a valid location from the backup dir

  $ hg up -q 0
  $ mkdir ../sym-link-target
#if symlink
  $ ln -s ../../../sym-link-target b
  $ ln -s ../../../sym-link-target d
#else
  $ touch b d
#endif
  $ hg up b1
  b: replacing untracked file
  d: replacing untracked file
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (activating bookmark b1)
#if symlink
  $ readlink.py .hg/origbackups/b
  .hg/origbackups/b -> ../../../sym-link-target
#endif

Perform an update that causes b/c and d to be backed up again - b/c should not go into the target dir

  $ hg up -q 0
  $ mkdir b
  $ echo c4 > b/c
  $ echo d3 > d
  $ hg up --verbose c1
  resolving manifests
  b/c: replacing untracked file
  d: replacing untracked file
  getting b/c
  creating directory: $TESTTMP/repo/.hg/origbackups/b
  removing conflicting file: $TESTTMP/repo/.hg/origbackups/b
  getting d
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (activating bookmark c1)
  $ cat .hg/origbackups/b/c
  c4
  $ cat .hg/origbackups/d
  d3
  $ ls ../sym-link-target

Incorrectly configure origbackuppath to be under a file

  $ echo data > .hg/badorigbackups
  $ hg up -q 0
  $ mkdir b
  $ echo c5 > b/c
  $ hg up --verbose c1 --config ui.origbackuppath=.hg/badorigbackups
  resolving manifests
  b/c: replacing untracked file
  getting b/c
  creating directory: $TESTTMP/repo/.hg/badorigbackups/b
  removing conflicting file: $TESTTMP/repo/.hg/badorigbackups
  getting d
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (activating bookmark c1)
  $ ls .hg/badorigbackups/b
  c