emit warning when a block or def is named "body"

[sqlalchemy-bot]

Migrated issue, originally created by Bérenger Enselme (@benselme)

This is using CPython 3.6.1

from mako.template import Template

if __name__ == '__main__':
    s = Template("""aaaa<%block name="bodi"></%block>bbbb""").render()
    assert s == 'aaaabbbb'  # success
    s = Template("""aaaa<%block name="body"></%block>bbbb""").render()
    assert s == 'aaaabbbb'  # failure, s == '\n '

[sqlalchemy-bot]

Michael Bayer (@zzzeek) wrote:

this is expected behavior. "body" is a pre-existing name with special behavior and is documented here. It is possible people use it as a "block" name intentionally.

[sqlalchemy-bot]

Bérenger Enselme (@benselme) wrote:

Thanks, I get it now. I was aware of the body() function but it was not obvious at all that naming a block "body" would overwrite it.

[sqlalchemy-bot]

Changes by Bérenger Enselme (@benselme):

• edited description

[sqlalchemy-bot]

Changes by Michael Bayer (@zzzeek):

• changed title from "Blank output when there is a block named "body"" to "emit warning when a block or def is named "body""