tests/test-dispatch.t

dirs._addpath: reinstate use of Py_CLEAR

I changed this to an explicit Py_DECREF + set to null in 6f0e6fa9fdd7. This was
a silly misunderstanding on my part -- for some reason I thought Py_CLEAR set
its argument to null only if its refcount reached 0. Turns out that's not
actually the case -- Py_CLEAR is just Py_DECREF + set to null with some
additional precautions around destructors that aren't relevant here.

The real bug that 6f0e6fa9fdd7 fixed was the fact that we were mutating the
string after setting it in the Python dictionary.

test command parsing and dispatch

  $ hg init a
  $ cd a

Redundant options used to crash (issue436):
  $ hg -v log -v
  $ hg -v log -v x

  $ echo a > a
  $ hg ci -Ama
  adding a

Missing arg:

  $ hg cat
  hg cat: invalid arguments
  hg cat [OPTION]... FILE...
  
  output the current or given revision of files
  
  options ([+] can be repeated):
  
   -o --output FORMAT       print output to file with formatted name
   -r --rev REV             print the given revision
      --decode              apply any matching decode filter
   -I --include PATTERN [+] include names matching the given patterns
   -X --exclude PATTERN [+] exclude names matching the given patterns
  
  (use "hg cat -h" to show more help)
  [255]

[defaults]

  $ hg cat a
  a
  $ cat >> $HGRCPATH <<EOF
  > [defaults]
  > cat = -r null
  > EOF
  $ hg cat a
  a: no such file in rev 000000000000
  [1]

  $ cd "$TESTTMP"

OSError "No such file or directory" / "The system cannot find the path
specified" should include filename even when it is empty

  $ hg -R a archive ''
  abort: *: '' (glob)
  [255]

#if no-outer-repo

No repo:

  $ hg cat
  abort: no repository found in '$TESTTMP' (.hg not found)!
  [255]

#endif