PEP 0492 -- Coroutines with async and await syntax. Issue #24017.
diff --git a/Lib/lib2to3/pgen2/tokenize.py b/Lib/lib2to3/pgen2/tokenize.py
index 3dd1ee9..690fec4 100644
--- a/Lib/lib2to3/pgen2/tokenize.py
+++ b/Lib/lib2to3/pgen2/tokenize.py
@@ -220,7 +220,7 @@
for tok in iterable:
toknum, tokval = tok[:2]
- if toknum in (NAME, NUMBER):
+ if toknum in (NAME, NUMBER, ASYNC, AWAIT):
tokval += ' '
if toknum == INDENT:
@@ -366,6 +366,10 @@
contline = None
indents = [0]
+ # 'stashed' and 'ctx' are used for async/await parsing
+ stashed = None
+ ctx = [('sync', 0)]
+
while 1: # loop over lines in stream
try:
line = readline()
@@ -406,6 +410,10 @@
pos = pos + 1
if pos == max: break
+ if stashed:
+ yield stashed
+ stashed = None
+
if line[pos] in '#\r\n': # skip comments or blank lines
if line[pos] == '#':
comment_token = line[pos:].rstrip('\r\n')
@@ -449,9 +457,15 @@
newline = NEWLINE
if parenlev > 0:
newline = NL
+ if stashed:
+ yield stashed
+ stashed = None
yield (newline, token, spos, epos, line)
elif initial == '#':
assert not token.endswith("\n")
+ if stashed:
+ yield stashed
+ stashed = None
yield (COMMENT, token, spos, epos, line)
elif token in triple_quoted:
endprog = endprogs[token]
@@ -459,6 +473,9 @@
if endmatch: # all on one line
pos = endmatch.end(0)
token = line[start:pos]
+ if stashed:
+ yield stashed
+ stashed = None
yield (STRING, token, spos, (lnum, pos), line)
else:
strstart = (lnum, start) # multiple lines
@@ -476,22 +493,64 @@
contline = line
break
else: # ordinary string
+ if stashed:
+ yield stashed
+ stashed = None
yield (STRING, token, spos, epos, line)
elif initial in namechars: # ordinary name
- yield (NAME, token, spos, epos, line)
+ if token in ('async', 'await'):
+ if ctx[-1][0] == 'async' and ctx[-1][1] < indents[-1]:
+ yield (ASYNC if token == 'async' else AWAIT,
+ token, spos, epos, line)
+ continue
+
+ tok = (NAME, token, spos, epos, line)
+ if token == 'async' and not stashed:
+ stashed = tok
+ continue
+
+ if token == 'def':
+ if (stashed
+ and stashed[0] == NAME
+ and stashed[1] == 'async'):
+
+ ctx.append(('async', indents[-1]))
+
+ yield (ASYNC, stashed[1],
+ stashed[2], stashed[3],
+ stashed[4])
+ stashed = None
+ else:
+ ctx.append(('sync', indents[-1]))
+
+ if stashed:
+ yield stashed
+ stashed = None
+
+ yield tok
elif initial == '\\': # continued stmt
# This yield is new; needed for better idempotency:
+ if stashed:
+ yield stashed
+ stashed = None
yield (NL, token, spos, (lnum, pos), line)
continued = 1
else:
if initial in '([{': parenlev = parenlev + 1
elif initial in ')]}': parenlev = parenlev - 1
+ if stashed:
+ yield stashed
+ stashed = None
yield (OP, token, spos, epos, line)
else:
yield (ERRORTOKEN, line[pos],
(lnum, pos), (lnum, pos+1), line)
pos = pos + 1
+ if stashed:
+ yield stashed
+ stashed = None
+
for indent in indents[1:]: # pop remaining indent levels
yield (DEDENT, '', (lnum, 0), (lnum, 0), '')
yield (ENDMARKER, '', (lnum, 0), (lnum, 0), '')