email.generator.Generator currently does not handle whitespace between
encoded words correctly when the encoded words span multiple lines. The
current generator will create an encoded word for each line. If the end
of the line happens to correspond with the end real word in the
plaintext, the generator will place an unencoded space at the start of
the subsequent lines to represent the whitespace between the plaintext
words.

A compliant decoder will strip all the whitespace from between two
encoded words which leads to missing spaces in the round-tripped
output.

The fix for this is to make sure that whitespace between two encoded
words ends up inside of one or the other of the encoded words. This
fix places the space inside of the second encoded word.

A second problem happens with continuation lines. A continuation line that
starts with whitespace and is followed by a non-encoded word is fine because
the newline between such continuation lines is defined as condensing to
a single space character. When the continuation line starts with whitespace
followed by an encoded word, however, the RFCs specify that the word is run
together with the encoded word on the previous line. This is because normal
words are filded on syntactic breaks by encoded words are not.

The solution to this is to add the whitespace to the start of the encoded word
on the continuation line.

Test cases are fromGH-92081

Rename a variable so it's not confused with the final variable.
(cherry picked from commita6fdb31)

Co-authored-by: Toshio Kuratomia.badger@gmail.com

pythongh-92081: Fix for email.generator.Generator with whitespace bet…

6f431e7

…ween encoded words. (pythonGH-92281)* Fix for email.generator.Generator with whitespace between encoded words.email.generator.Generator currently does not handle whitespace betweenencoded words correctly when the encoded words span multiple lines.  Thecurrent generator will create an encoded word for each line.  If the endof the line happens to correspond with the end real word in theplaintext, the generator will place an unencoded space at the start ofthe subsequent lines to represent the whitespace between the plaintextwords.A compliant decoder will strip all the whitespace from between twoencoded words which leads to missing spaces in the round-trippedoutput.The fix for this is to make sure that whitespace between two encodedwords ends up inside of one or the other of the encoded words.  Thisfix places the space inside of the second encoded word.A second problem happens with continuation lines.  A continuation line thatstarts with whitespace and is followed by a non-encoded word is fine becausethe newline between such continuation lines is defined as condensing toa single space character.  When the continuation line starts with whitespacefollowed by an encoded word, however, the RFCs specify that the word is runtogether with the encoded word on the previous line.  This is because normalwords are filded on syntactic breaks by encoded words are not.The solution to this is to add the whitespace to the start of the encoded wordon the continuation line.Test cases are frompythonGH-92081* Rename a variable so it's not confused with the final variable.(cherry picked from commita6fdb31)Co-authored-by: Toshio Kuratomi <a.badger@gmail.com>