Previously, we used the default character encoding from the project
properties to determine how strings and character constants in the
entire source file should be encoded. Now we switch between
encodings as needed. The default character encoding is no longer
relevant.
High ASCII is now an actual encoding, rather than acting like ASCII
that sometimes doesn't work. Because we can do high ASCII character
operands with "| $80", we don't output a .enc to switch from ASCII
to high ASCII unless we need to generate a string. (If we're
already in high ASCII mode, the "| $80" isn't required but won't
hurt anything.)
We now do a scan up front to see if ASCII or high ASCII is needed,
and only output the .cdefs for the encodings that are actually used.
The only gap in the matrix is high ASCII DCI strings -- the ".shift"
pseudo-op rejects text if the string doesn't start with the high
bit clear.
I didn't think it made sense, but I found something that used it,
so apparently it's a thing. This updates the operand editor to
let you choose PETSCII+DCI, and updates the assemblers to handle
it correctly (really just 64tass, since the others either don't
have a DCI directive or don't deal with PETSCII at all).
Changed the char-encoding sample from "bad dcI" to "pet dcI", and
updated the documentation.
The documentation for 64tass says you're required to pass "--ascii"
when the source file is ASCII (as opposed to PETSCII). We were
ignoring this, but it turns out that everything works a bit better
if we don't.
So we now pass "--ascii" on the command line, and add a two-line
character encoding definition to every file that is generated with
ASCII as the default encoding. The sg_petscii and sg_screen
encodings go away, as PETSCII is now the default, and we can use the
built-in "screen" encoding.
All tests use the same data file and nearly the same project file.
The only difference is the default text encoding property setting.
For "-a" it's ASCII, for "-p" it's PETSCII, for "-s" it's C64 screen
code. Right now this only affects the code generated for 64tass.
The test itself is a collection of strings and characters in the
supported character encodings. How these are handled varies
significantly between assemblers.
