summaryrefslogtreecommitdiff
path: root/python/helpers/pydev/third_party/pep8/lib2to3/lib2to3/fixes/fix_raise.py
diff options
context:
space:
mode:
Diffstat (limited to 'python/helpers/pydev/third_party/pep8/lib2to3/lib2to3/fixes/fix_raise.py')
-rw-r--r--python/helpers/pydev/third_party/pep8/lib2to3/lib2to3/fixes/fix_raise.py90
1 files changed, 90 insertions, 0 deletions
diff --git a/python/helpers/pydev/third_party/pep8/lib2to3/lib2to3/fixes/fix_raise.py b/python/helpers/pydev/third_party/pep8/lib2to3/lib2to3/fixes/fix_raise.py
new file mode 100644
index 000000000000..b958ba0129de
--- /dev/null
+++ b/python/helpers/pydev/third_party/pep8/lib2to3/lib2to3/fixes/fix_raise.py
@@ -0,0 +1,90 @@
+"""Fixer for 'raise E, V, T'
+
+raise -> raise
+raise E -> raise E
+raise E, V -> raise E(V)
+raise E, V, T -> raise E(V).with_traceback(T)
+raise E, None, T -> raise E.with_traceback(T)
+
+raise (((E, E'), E''), E'''), V -> raise E(V)
+raise "foo", V, T -> warns about string exceptions
+
+
+CAVEATS:
+1) "raise E, V" will be incorrectly translated if V is an exception
+ instance. The correct Python 3 idiom is
+
+ raise E from V
+
+ but since we can't detect instance-hood by syntax alone and since
+ any client code would have to be changed as well, we don't automate
+ this.
+"""
+# Author: Collin Winter
+
+# Local imports
+from .. import pytree
+from ..pgen2 import token
+from .. import fixer_base
+from ..fixer_util import Name, Call, Attr, ArgList, is_tuple
+
+class FixRaise(fixer_base.BaseFix):
+
+ BM_compatible = True
+ PATTERN = """
+ raise_stmt< 'raise' exc=any [',' val=any [',' tb=any]] >
+ """
+
+ def transform(self, node, results):
+ syms = self.syms
+
+ exc = results["exc"].clone()
+ if exc.type == token.STRING:
+ msg = "Python 3 does not support string exceptions"
+ self.cannot_convert(node, msg)
+ return
+
+ # Python 2 supports
+ # raise ((((E1, E2), E3), E4), E5), V
+ # as a synonym for
+ # raise E1, V
+ # Since Python 3 will not support this, we recurse down any tuple
+ # literals, always taking the first element.
+ if is_tuple(exc):
+ while is_tuple(exc):
+ # exc.children[1:-1] is the unparenthesized tuple
+ # exc.children[1].children[0] is the first element of the tuple
+ exc = exc.children[1].children[0].clone()
+ exc.prefix = u" "
+
+ if "val" not in results:
+ # One-argument raise
+ new = pytree.Node(syms.raise_stmt, [Name(u"raise"), exc])
+ new.prefix = node.prefix
+ return new
+
+ val = results["val"].clone()
+ if is_tuple(val):
+ args = [c.clone() for c in val.children[1:-1]]
+ else:
+ val.prefix = u""
+ args = [val]
+
+ if "tb" in results:
+ tb = results["tb"].clone()
+ tb.prefix = u""
+
+ e = exc
+ # If there's a traceback and None is passed as the value, then don't
+ # add a call, since the user probably just wants to add a
+ # traceback. See issue #9661.
+ if val.type != token.NAME or val.value != u"None":
+ e = Call(exc, args)
+ with_tb = Attr(e, Name(u'with_traceback')) + [ArgList([tb])]
+ new = pytree.Node(syms.simple_stmt, [Name(u"raise")] + with_tb)
+ new.prefix = node.prefix
+ return new
+ else:
+ return pytree.Node(syms.raise_stmt,
+ [Name(u"raise"), Call(exc, args)],
+ prefix=node.prefix)