ed: newline append versus 'r' command

[mknos]

• ed requires that all lines in its buffer are terminated with "\n"
• ed attempts to append a "\n" if it is missing on the last line of input
• The existing append logic in edEdit() was observed to only work for 'E' and 'e' commands, but not 'r'
• With E/e the entire buffer is destroyed and replaced with the content from the new file
• The append logic would then check the final line in buffer after the buffer was replaced (this worked ok)
• The 'r' command inserts the file content to any position within the existing buffer (e.g. 0r to insert to beginning of buffer)
• Checking for missing newline at end of buffer doesn't work if the data is inserted at a different location in buffer
• More general fix: check final line of tmp_lines list before it is applied to the buffer
• To test, construct a file 'in' with a missing newline at end, then read it into the beginning of buffer (initiated from file 'in2')

%hd in
00000000  68 65 6c 6c 6f 0a 67 6f  6f 64 62 79 65           |hello.goodbye|
0000000d
%perl ed in2
4595
P
*1,5n
1	#!/usr/bin/perl
2	
3	=begin metadata
4	
5	Name: awk
*0r in
Newline appended
13
*1,5n
1	hello
2	goodbye
3	#!/usr/bin/perl
4	
5	=begin metadata
*Q