$ echo "[extensions]" >> $HGRCPATH

  $ echo "patchbomb=" >> $HGRCPATH

  $ hg init t

  $ cd t

  $ echo a > a

  $ hg commit -Ama -d '1 0'

  adding a

  $ hg email --date '1970-1-1 0:1' -n -f quux -t foo -c bar -r tip

  this patch series consists of 1 patches.

  displaying [PATCH] a ...

  Content-Type: text/plain; charset="us-ascii"

  MIME-Version: 1.0

  Content-Transfer-Encoding: 7bit

  Subject: [PATCH] a

  X-Mercurial-Node: 8580ff50825a50c8f716709acdf8de0deddcd6ab

  X-Mercurial-Series-Index: 1

  X-Mercurial-Series-Total: 1

  Message-Id: <8580ff50825a50c8f716.60@*> (glob)

  User-Agent: Mercurial-patchbomb/* (glob)

  Date: Thu, 01 Jan 1970 00:01:00 +0000

  From: quux

  To: foo

  Cc: bar

  # HG changeset patch

  # User test

  # Date 1 0

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

  # Node ID 8580ff50825a50c8f716709acdf8de0deddcd6ab

  # Parent  0000000000000000000000000000000000000000

  a

  diff -r 000000000000 -r 8580ff50825a a

  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000

  +++ b/a	Thu Jan 01 00:00:01 1970 +0000

  @@ -0,0 +1,1 @@

  +a

  $ hg --config ui.interactive=1 email --confirm -n -f quux -t foo -c bar -r tip<<EOF

  > n

  > EOF

  this patch series consists of 1 patches.

  Final summary:

  From: quux

  To: foo

  Cc: bar

  Subject: [PATCH] a

   a |  1 +

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

  are you sure you want to send (yn)? abort: patchbomb canceled

  [255]

  $ echo b > b

  $ hg commit -Amb -d '2 0'

  adding b

  $ hg email --date '1970-1-1 0:2' -n -f quux -t foo -c bar -s test -r 0:tip

  this patch series consists of 2 patches.

  Write the introductory message for the patch series.

  displaying [PATCH 0 of 2] test ...

  Content-Type: text/plain; charset="us-ascii"

  MIME-Version: 1.0

  Content-Transfer-Encoding: 7bit

  Subject: [PATCH 0 of 2] test

  Message-Id: <patchbomb.120@*> (glob)

  User-Agent: Mercurial-patchbomb/* (glob)

  Date: Thu, 01 Jan 1970 00:02:00 +0000

  From: quux

  To: foo

  Cc: bar

  displaying [PATCH 1 of 2] a ...

  Content-Type: text/plain; charset="us-ascii"

  MIME-Version: 1.0

  Content-Transfer-Encoding: 7bit

  Subject: [PATCH 1 of 2] a

  X-Mercurial-Node: 8580ff50825a50c8f716709acdf8de0deddcd6ab

  X-Mercurial-Series-Index: 1

  X-Mercurial-Series-Total: 2

  Message-Id: <8580ff50825a50c8f716.121@*> (glob)

  In-Reply-To: <patchbomb.120@*> (glob)

  References: <patchbomb.120@*> (glob)

  User-Agent: Mercurial-patchbomb/* (glob)

  Date: Thu, 01 Jan 1970 00:02:01 +0000

  From: quux

  To: foo

  Cc: bar

  # HG changeset patch

  # User test

  # Date 1 0

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

  # Node ID 8580ff50825a50c8f716709acdf8de0deddcd6ab

  # Parent  0000000000000000000000000000000000000000

  a

  diff -r 000000000000 -r 8580ff50825a a

  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000

  +++ b/a	Thu Jan 01 00:00:01 1970 +0000

  @@ -0,0 +1,1 @@

  +a

  displaying [PATCH 2 of 2] b ...

  Content-Type: text/plain; charset="us-ascii"

  MIME-Version: 1.0

  Content-Transfer-Encoding: 7bit

  Subject: [PATCH 2 of 2] b

  X-Mercurial-Node: 97d72e5f12c7e84f85064aa72e5a297142c36ed9

  X-Mercurial-Series-Index: 2

  X-Mercurial-Series-Total: 2

  Message-Id: <97d72e5f12c7e84f8506.122@*> (glob)

  In-Reply-To: <patchbomb.120@*> (glob)

  References: <patchbomb.120@*> (glob)

  User-Agent: Mercurial-patchbomb/* (glob)

  Date: Thu, 01 Jan 1970 00:02:02 +0000

  From: quux

  To: foo

  Cc: bar

  # HG changeset patch

  # User test

  # Date 2 0

  #      Thu Jan 01 00:00:02 1970 +0000

  # Node ID 97d72e5f12c7e84f85064aa72e5a297142c36ed9

  # Parent  8580ff50825a50c8f716709acdf8de0deddcd6ab

  b

  diff -r 8580ff50825a -r 97d72e5f12c7 b

  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000

  +++ b/b	Thu Jan 01 00:00:02 1970 +0000

  @@ -0,0 +1,1 @@

  +b

.hg/last-email.txt

  $ cat > editor.sh << '__EOF__'

  > echo "a precious introductory message" > "$1"

  > __EOF__

  $ HGEDITOR="\"sh\" \"`pwd`/editor.sh\"" hg email -n -t foo -s test -r 0:tip > /dev/null

  $ cat .hg/last-email.txt

  a precious introductory message

  $ hg email -m test.mbox -f quux -t foo -c bar -s test 0:tip \

  > --config extensions.progress= --config progress.assume-tty=1 \

  > --config progress.delay=0 --config progress.refresh=0 \

  > --config progress.width=60

  this patch series consists of 2 patches.

  Write the introductory message for the patch series.

  \r (no-eol) (esc)

  sending [                                             ] 0/3\r (no-eol) (esc)

  sending [                                             ] 0/3\r (no-eol) (esc)

                                                              \r (no-eol) (esc)

  \r (no-eol) (esc)

                                                              \r (no-eol) (esc)

  \r (no-eol) (esc)

  sending [==============>                              ] 1/3\r (no-eol) (esc)

  sending [==============>                              ] 1/3\r (no-eol) (esc)

                                                              \r (no-eol) (esc)

  \r (no-eol) (esc)

                                                              \r (no-eol) (esc)

  \r (no-eol) (esc)

  sending [=============================>               ] 2/3\r (no-eol) (esc)

  sending [=============================>               ] 2/3\r (no-eol) (esc)

                                                              \r (esc)

  sending [PATCH 0 of 2] test ...

  sending [PATCH 1 of 2] a ...

  sending [PATCH 2 of 2] b ...

  $ cd ..

  $ hg clone -q t t2

  $ cd t2

  $ echo c > c

  $ hg commit -Amc -d '3 0'

  adding c

  $ cat > description <<EOF

  > a multiline

  > 

  > description

  > EOF

test bundle and description:

  $ hg email --date '1970-1-1 0:3' -n -f quux -t foo \

  >  -c bar -s test -r tip -b --desc description

  searching for changes

  1 changesets found

  displaying test ...

  Content-Type: multipart/mixed; boundary="===*" (glob)

  MIME-Version: 1.0

  Subject: test

  Message-Id: <patchbomb.180@*> (glob)

  User-Agent: Mercurial-patchbomb/* (glob)

  Date: Thu, 01 Jan 1970 00:03:00 +0000

  From: quux

  To: foo

  Cc: bar

  --===* (glob)

  Content-Type: text/plain; charset="us-ascii"

  MIME-Version: 1.0

  Content-Transfer-Encoding: 7bit

  a multiline

  description

  --===* (glob)

  Content-Type: application/x-mercurial-bundle

  MIME-Version: 1.0

  Content-Disposition: attachment; filename="bundle.hg"

  Content-Transfer-Encoding: base64

  SEcxMEJaaDkxQVkmU1nvR7I3AAAN////lFYQWj1/4HwRkdC/AywIAk0E4pfoSIIIgQCgGEQOcLAA

  2tA1VPyp4mkeoG0EaaPU0GTT1GjRiNPIg9CZGBqZ6UbU9J+KFU09DNUaGgAAAAAANAGgAAAAA1U8

  oGgAADQGgAANNANAAAAAAZipFLz3XoakCEQB3PVPyHJVi1iYkAAKQAZQGpQGZESInRnCFMqLDla2

  Bx3qfRQeA2N4lnzKkAmP8kR2asievLLXXebVU8Vg4iEBqcJNJAxIapSU6SM4888ZAciRG6MYAIEE

  SlIBpFisgGkyRjX//TMtfcUAEsGu56+YnE1OlTZmzKm8BSu2rvo4rHAYYaadIFFuTy0LYgIkgLVD

  sgVa2F19D1tx9+hgbAygLgQwaIqcDdgA4BjQgIiz/AEP72++llgDKhKducqodGE4B0ETqF3JFOFC

  Q70eyNw=

  --===*-- (glob)

utf-8 patch:

  $ python -c 'fp = open("utf", "wb"); fp.write("h\xC3\xB6mma!\n"); fp.close();'

  $ hg commit -A -d '4 0' -m 'utf-8 content'

  adding description

  adding utf

no mime encoding for email --test:

  $ hg email --date '1970-1-1 0:4' -f quux -t foo -c bar -r tip -n

  this patch series consists of 1 patches.

  displaying [PATCH] utf-8 content ...

  Content-Type: text/plain; charset="us-ascii"

  MIME-Version: 1.0

  Content-Transfer-Encoding: 8bit

  Subject: [PATCH] utf-8 content

  X-Mercurial-Node: 909a00e13e9d78b575aeee23dddbada46d5a143f

  X-Mercurial-Series-Index: 1

  X-Mercurial-Series-Total: 1

  Message-Id: <909a00e13e9d78b575ae.240@*> (glob)

  User-Agent: Mercurial-patchbomb/* (glob)

  Date: Thu, 01 Jan 1970 00:04:00 +0000

  From: quux

  To: foo

  Cc: bar

  # HG changeset patch

  # User test

  # Date 4 0

  #      Thu Jan 01 00:00:04 1970 +0000

  # Node ID 909a00e13e9d78b575aeee23dddbada46d5a143f

  # Parent  ff2c9fa2018b15fa74b33363bda9527323e2a99f

  utf-8 content

  diff -r ff2c9fa2018b -r 909a00e13e9d description

  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000

  +++ b/description	Thu Jan 01 00:00:04 1970 +0000

  @@ -0,0 +1,3 @@

  +a multiline

  +

  +description

  diff -r ff2c9fa2018b -r 909a00e13e9d utf

  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000

  +++ b/utf	Thu Jan 01 00:00:04 1970 +0000

  @@ -0,0 +1,1 @@

  +h\xc3\xb6mma! (esc)

mime encoded mbox (base64):

  $ hg email --date '1970-1-1 0:4' -f 'Q <quux>' -t foo -c bar -r tip -m mbox

  this patch series consists of 1 patches.

  sending [PATCH] utf-8 content ...

  $ cat mbox

  From quux ... ... .. ..:..:.. .... (re)

  Content-Type: text/plain; charset="utf-8"

  MIME-Version: 1.0

  Content-Transfer-Encoding: base64

  Subject: [PATCH] utf-8 content

  X-Mercurial-Node: 909a00e13e9d78b575aeee23dddbada46d5a143f

  X-Mercurial-Series-Index: 1

  X-Mercurial-Series-Total: 1

  Message-Id: <909a00e13e9d78b575ae.240@*> (glob)

  User-Agent: Mercurial-patchbomb/* (glob)

  Date: Thu, 01 Jan 1970 00:04:00 +0000

  From: Q <quux>

  To: foo

  Cc: bar

  IyBIRyBjaGFuZ2VzZXQgcGF0Y2gKIyBVc2VyIHRlc3QKIyBEYXRlIDQgMAojICAgICAgVGh1IEph

  biAwMSAwMDowMDowNCAxOTcwICswMDAwCiMgTm9kZSBJRCA5MDlhMDBlMTNlOWQ3OGI1NzVhZWVl

  MjNkZGRiYWRhNDZkNWExNDNmCiMgUGFyZW50ICBmZjJjOWZhMjAxOGIxNWZhNzRiMzMzNjNiZGE5

  NTI3MzIzZTJhOTlmCnV0Zi04IGNvbnRlbnQKCmRpZmYgLXIgZmYyYzlmYTIwMThiIC1yIDkwOWEw

  MGUxM2U5ZCBkZXNjcmlwdGlvbgotLS0gL2Rldi9udWxsCVRodSBKYW4gMDEgMDA6MDA6MDAgMTk3

  MCArMDAwMAorKysgYi9kZXNjcmlwdGlvbglUaHUgSmFuIDAxIDAwOjAwOjA0IDE5NzAgKzAwMDAK

  QEAgLTAsMCArMSwzIEBACithIG11bHRpbGluZQorCitkZXNjcmlwdGlvbgpkaWZmIC1yIGZmMmM5

  ZmEyMDE4YiAtciA5MDlhMDBlMTNlOWQgdXRmCi0tLSAvZGV2L251bGwJVGh1IEphbiAwMSAwMDow

  MDowMCAxOTcwICswMDAwCisrKyBiL3V0ZglUaHUgSmFuIDAxIDAwOjAwOjA0IDE5NzAgKzAwMDAK

  QEAgLTAsMCArMSwxIEBACitow7ZtbWEhCg==

  $ python -c 'print open("mbox").read().split("\n\n")[1].decode("base64")'

  # HG changeset patch

  # User test

  # Date 4 0

  #      Thu Jan 01 00:00:04 1970 +0000

  # Node ID 909a00e13e9d78b575aeee23dddbada46d5a143f

  # Parent  ff2c9fa2018b15fa74b33363bda9527323e2a99f

  utf-8 content

  diff -r ff2c9fa2018b -r 909a00e13e9d description

  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000

  +++ b/description	Thu Jan 01 00:00:04 1970 +0000

  @@ -0,0 +1,3 @@

  +a multiline

  +

  +description

  diff -r ff2c9fa2018b -r 909a00e13e9d utf

  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000

  +++ b/utf	Thu Jan 01 00:00:04 1970 +0000

  @@ -0,0 +1,1 @@

  +h\xc3\xb6mma! (esc)

  $ rm mbox

mime encoded mbox (quoted-printable):

  $ python -c 'fp = open("long", "wb"); fp.write("%s\nfoo\n\nbar\n" % ("x" * 1024)); fp.close();'

  $ hg commit -A -d '4 0' -m 'long line'

  adding long

no mime encoding for email --test: