$ hg init repo

  $ cd repo

  $ i=0; while [ "$i" -lt 213 ]; do echo a >> a; i=`expr $i + 1`; done

  $ hg add a

  $ cp a b

  $ hg add b

Wide diffstat:

  $ hg diff --stat

   a |  213 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

   b |  213 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

   2 files changed, 426 insertions(+), 0 deletions(-)

diffstat width:

  $ COLUMNS=24 hg diff --config ui.interactive=true --stat

   a |  213 ++++++++++++++

   b |  213 ++++++++++++++

   2 files changed, 426 insertions(+), 0 deletions(-)

  $ hg ci -m adda

  $ cat >> a <<EOF

  > a

  > a

  > a

  > EOF

Narrow diffstat:

  $ hg diff --stat

   a |  3 +++

   1 files changed, 3 insertions(+), 0 deletions(-)

  $ hg ci -m appenda

  >>> open("c", "wb").write(b"\0")

  $ touch d

  $ hg add c d

Binary diffstat:

  $ hg diff --stat

   c |  Bin 

   1 files changed, 0 insertions(+), 0 deletions(-)

Binary git diffstat:

  $ hg diff --stat --git

   c |  Bin 

   d |    0 

   2 files changed, 0 insertions(+), 0 deletions(-)

  $ hg ci -m createb

  >>> open("file with spaces", "wb").write(b"\0")

  $ hg add "file with spaces"

Filename with spaces diffstat:

  $ hg diff --stat

   file with spaces |  Bin 

   1 files changed, 0 insertions(+), 0 deletions(-)

Filename with spaces git diffstat:

  $ hg diff --stat --git

   file with spaces |  Bin 

   1 files changed, 0 insertions(+), 0 deletions(-)

Filename without "a/" or "b/" (issue5759):

  $ hg diff --config 'diff.noprefix=1' -c1 --stat --git

   a |  3 +++

   1 files changed, 3 insertions(+), 0 deletions(-)

  $ hg diff --config 'diff.noprefix=1' -c2 --stat --git

   c |  Bin 

   d |    0 

   2 files changed, 0 insertions(+), 0 deletions(-)

  $ hg log --config 'diff.noprefix=1' -r '1:' -p --stat --git

  changeset:   1:3a95b07bb77f

  user:        test

  date:        Thu Jan 01 00:00:00 1970 +0000

  summary:     appenda

   a |  3 +++

   1 files changed, 3 insertions(+), 0 deletions(-)

  diff --git a a

  --- a

  +++ a

  @@ -211,3 +211,6 @@

   a

   a

   a

  +a

  +a

  +a

  changeset:   2:c60a6c753773

  tag:         tip

  user:        test

  date:        Thu Jan 01 00:00:00 1970 +0000

  summary:     createb

   c |  Bin 

   d |    0 

   2 files changed, 0 insertions(+), 0 deletions(-)

  diff --git c c

  new file mode 100644

  index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..f76dd238ade08917e6712764a16a22005a50573d

  GIT binary patch

  literal 1

  Ic${MZ000310RR91

  diff --git d d

  new file mode 100644

diffstat within directories:

  $ hg rm -f 'file with spaces'

  $ mkdir dir1 dir2

  $ echo new1 > dir1/new

  $ echo new2 > dir2/new

  $ hg add dir1/new dir2/new

  $ hg diff --stat

   dir1/new |  1 +

   dir2/new |  1 +

   2 files changed, 2 insertions(+), 0 deletions(-)

  $ hg diff --stat --root dir1

   new |  1 +

   1 files changed, 1 insertions(+), 0 deletions(-)

  $ hg diff --stat --root dir1 dir2

  warning: dir2 not inside relative root dir1

  $ hg diff --stat --root dir1 -I dir1/old

  $ cd dir1

  $ hg diff --stat .

   dir1/new |  1 +

   1 files changed, 1 insertions(+), 0 deletions(-)

  $ hg diff --stat --root .

   new |  1 +

   1 files changed, 1 insertions(+), 0 deletions(-)

  $ hg diff --stat --root ../dir1 ../dir2

  warning: ../dir2 not inside relative root .

  $ hg diff --stat --root . -I old

  $ cd ..

Files with lines beginning with '--' or '++' should be properly counted in diffstat

  $ hg up -Cr tip

  0 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ rm dir1/new

  $ rm dir2/new

  $ rm "file with spaces"

  $ cat > file << EOF

  > line 1

  > line 2

  > line 3

  > EOF

  $ hg commit -Am file

  adding file

Lines added starting with '--' should count as additions

  $ cat > file << EOF

  > line 1

  > -- line 2, with dashes

  > line 3

  > EOF

  $ hg diff --root .

  diff -r be1569354b24 file

  --- a/file	Thu Jan 01 00:00:00 1970 +0000

  +++ b/file	* (glob)

  @@ -1,3 +1,3 @@

   line 1

  -line 2

  +-- line 2, with dashes

   line 3

  $ hg diff --root . --stat

   file |  2 +-

   1 files changed, 1 insertions(+), 1 deletions(-)

Lines changed starting with '--' should count as deletions

  $ hg commit -m filev2

  $ cat > file << EOF

  > line 1

  > -- line 2, with dashes, changed again

  > line 3

  > EOF

  $ hg diff --root .

  diff -r 160f7c034df6 file

  --- a/file	Thu Jan 01 00:00:00 1970 +0000

  +++ b/file	* (glob)

  @@ -1,3 +1,3 @@

   line 1

  --- line 2, with dashes

  +-- line 2, with dashes, changed again

   line 3

  $ hg diff --root . --stat

   file |  2 +-

   1 files changed, 1 insertions(+), 1 deletions(-)

Lines changed starting with '--' should count as deletions

and starting with '++' should count as additions

  $ cat > file << EOF

  > line 1

  > ++ line 2, switched dashes to plusses

  > line 3

  > EOF

  $ hg diff --root .

  diff -r 160f7c034df6 file

  --- a/file	Thu Jan 01 00:00:00 1970 +0000

  +++ b/file	* (glob)

  @@ -1,3 +1,3 @@

   line 1

  --- line 2, with dashes

  +++ line 2, switched dashes to plusses

   line 3

  $ hg diff --root . --stat

   file |  2 +-

   1 files changed, 1 insertions(+), 1 deletions(-)