tests/test-parents.t

util: add the code path to "cachefunc()" for the function taking no arguments

Before this patch, "util.cachefunc()" caches the value returned by the
specified function into dictionary "cache", even if the specified
function takes no arguments.

In such case, "cache" has at most one entry, and distinction between
entries in "cache" is meaningless.

This patch adds the code path to "cachefunc()" for the function taking
no arguments for efficiency: to store only one cached value, using
list "cache" is a little faster than using dictionary "cache".

test parents command

  $ hg init repo
  $ cd repo

no working directory

  $ hg parents

  $ echo a > a
  $ echo b > b
  $ hg ci -Amab -d '0 0'
  adding a
  adding b
  $ echo a >> a
  $ hg ci -Ama -d '1 0'
  $ echo b >> b
  $ hg ci -Amb -d '2 0'
  $ echo c > c
  $ hg ci -Amc -d '3 0'
  adding c
  $ hg up -C 1
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo d > c
  $ hg ci -Amc2 -d '4 0'
  adding c
  created new head
  $ hg up -C 3
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved


  $ hg parents
  changeset:   3:02d851b7e549
  user:        test
  date:        Thu Jan 01 00:00:03 1970 +0000
  summary:     c
  

  $ hg parents a
  changeset:   1:d786049f033a
  user:        test
  date:        Thu Jan 01 00:00:01 1970 +0000
  summary:     a
  

hg parents c, single revision

  $ hg parents c
  changeset:   3:02d851b7e549
  user:        test
  date:        Thu Jan 01 00:00:03 1970 +0000
  summary:     c
  

  $ hg parents -r 3 c
  abort: 'c' not found in manifest!
  [255]

  $ hg parents -r 2
  changeset:   1:d786049f033a
  user:        test
  date:        Thu Jan 01 00:00:01 1970 +0000
  summary:     a
  

  $ hg parents -r 2 a
  changeset:   1:d786049f033a
  user:        test
  date:        Thu Jan 01 00:00:01 1970 +0000
  summary:     a
  

  $ hg parents -r 2 ../a
  abort: ../a not under root '$TESTTMP/repo' (glob)
  [255]


cd dir; hg parents -r 2 ../a

  $ mkdir dir
  $ cd dir
  $ hg parents -r 2 ../a
  changeset:   1:d786049f033a
  user:        test
  date:        Thu Jan 01 00:00:01 1970 +0000
  summary:     a
  
  $ hg parents -r 2 path:a
  changeset:   1:d786049f033a
  user:        test
  date:        Thu Jan 01 00:00:01 1970 +0000
  summary:     a
  
  $ cd ..

  $ hg parents -r 2 glob:a
  abort: can only specify an explicit filename
  [255]


merge working dir with 2 parents, hg parents c

  $ HGMERGE=true hg merge
  merging c
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg parents c
  changeset:   3:02d851b7e549
  user:        test
  date:        Thu Jan 01 00:00:03 1970 +0000
  summary:     c
  
  changeset:   4:48cee28d4b4e
  tag:         tip
  parent:      1:d786049f033a
  user:        test
  date:        Thu Jan 01 00:00:04 1970 +0000
  summary:     c2
  


merge working dir with 1 parent, hg parents

  $ hg up -C 2
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ HGMERGE=true hg merge -r 4
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg parents
  changeset:   2:6cfac479f009
  user:        test
  date:        Thu Jan 01 00:00:02 1970 +0000
  summary:     b
  
  changeset:   4:48cee28d4b4e
  tag:         tip
  parent:      1:d786049f033a
  user:        test
  date:        Thu Jan 01 00:00:04 1970 +0000
  summary:     c2
  

merge working dir with 1 parent, hg parents c

  $ hg parents c
  changeset:   4:48cee28d4b4e
  tag:         tip
  parent:      1:d786049f033a
  user:        test
  date:        Thu Jan 01 00:00:04 1970 +0000
  summary:     c2
  

  $ cd ..