Better catch syntax

The syntax is now changed to:

  (catch [] BODY)
  (catch [Exception] BODY)
  (catch [e Exception] BODY)
  (catch [e [Exception1 Exception2]] BODY)

Signed-off-by: Julien Danjou <julien@danjou.info>
This commit is contained in:
Julien Danjou 2013-04-07 17:22:57 +02:00
parent 3c735d18bd
commit 6dec894a0c
3 changed files with 124 additions and 18 deletions

View File

@ -1,4 +1,7 @@
# -*- encoding: utf-8 -*-
#
# Copyright (c) 2013 Paul Tagliamonte <paultag@debian.org>
# Copyright (c) 2013 Julien Danjou <julien@danjou.info>
#
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the "Software"),
@ -191,12 +194,30 @@ class HyASTCompiler(object):
orelse=[])
@builds("catch")
@checkargs(min=2)
def compile_catch_expression(self, expr):
expr.pop(0) # catch
_type = self.compile(expr.pop(0))
name = expr.pop(0)
try:
exceptions = expr.pop(0)
except IndexError:
exceptions = []
# exceptions catch should be either:
# [[list of exceptions]]
# or
# [variable [list of exceptions]]
# or
# [variable exception]
# or
# [exception]
# or
# []
if len(exceptions) > 2:
raise TypeError("`catch' exceptions list is too long")
# [variable [list of exceptions]]
# let's pop variable and use it as name
if len(exceptions) == 2:
name = exceptions.pop(0)
if sys.version_info[0] >= 3:
# Python3 features a change where the Exception handler
# moved the name from a Name() to a pure Python String type.
@ -207,13 +228,43 @@ class HyASTCompiler(object):
else:
# Python2 requires an ast.Name, set to ctx Store.
name = self._storeize(self.compile(name))
else:
name = None
try:
exceptions_list = exceptions.pop(0)
except IndexError:
exceptions_list = []
if isinstance(exceptions_list, list):
if len(exceptions_list):
# [FooBar BarFoo] → catch Foobar and BarFoo exceptions
_type = ast.Tuple(elts=[self.compile(x)
for x in exceptions_list],
lineno=expr.start_line,
col_offset=expr.start_column,
ctx=ast.Load())
else:
# [] → all exceptions catched
_type = None
elif isinstance(exceptions_list, HySymbol):
_type = self.compile(exceptions_list)
else:
raise TypeError("`catch' needs a valid exception list to catch")
if len(expr) == 0:
# No body
body = [ast.Pass(lineno=expr.start_line,
col_offset=expr.start_column)]
else:
body = self._code_branch([self.compile(x) for x in expr])
return ast.ExceptHandler(
lineno=expr.start_line,
col_offset=expr.start_column,
type=_type,
name=name,
body=self._code_branch([self.compile(x) for x in expr]))
body=body)
def _code_branch(self, branch):
if isinstance(branch, list):

View File

@ -116,13 +116,20 @@ def test_ast_bad_try():
def test_ast_good_catch():
"Make sure AST can compile valid catch"
hy_compile(tokenize("(catch 1 2)"))
hy_compile(tokenize("(catch)"))
hy_compile(tokenize("(catch [])"))
hy_compile(tokenize("(catch [Foobar])"))
# hy_compile(tokenize("(catch [[]])"))
# hy_compile(tokenize("(catch [x FooBar])"))
# hy_compile(tokenize("(catch [x [FooBar BarFoo]])"))
# hy_compile(tokenize("(catch [x [FooBar BarFoo]])"))
def test_ast_bad_catch():
"Make sure AST can't compile invalid catch"
cant_compile("(catch)")
cant_compile("(catch 1)")
cant_compile("(catch [1 3])")
cant_compile("(catch [x [FooBar] BarBar]])")
def test_ast_good_assert():

View File

@ -164,8 +164,56 @@
"NATIVE: test Exceptions"
(try
(throw (KeyError))
(catch IOError e (assert (= 2 1)))
(catch KeyError e (+ 1 1) (assert (= 1 1)))))
(catch [[IOError]] (assert false))
(catch [e [KeyError]] (assert e)))
(try
(get [1] 3)
(catch [IndexError] (assert true))
(catch [IndexError] (pass)))
(try
(print foobar42ofthebaz)
(catch [IndexError] (assert false))
(catch [NameError] (pass)))
(try
(get [1] 3)
(catch [e IndexError] (assert (isinstance e IndexError))))
(try
(get [1] 3)
(catch [e [IndexError NameError]] (assert (isinstance e IndexError))))
(try
(print foobar42ofthebaz)
(catch [e [IndexError NameError]] (assert (isinstance e NameError))))
(try
(print foobar42)
(catch [[IndexError NameError]] (pass)))
(try
(get [1] 3)
(catch [[IndexError NameError]] (pass)))
(try
(print foobar42ofthebaz)
(catch))
(try
(print foobar42ofthebaz)
(catch []))
(try
(print foobar42ofthebaz)
(catch [] (pass)))
(try
(print foobar42ofthebaz)
(catch []
(setv foobar42ofthebaz 42)
(assert (= foobar42ofthebaz 42)))))
(defn test-earmuffs []
"NATIVE: Test earmuffs"
@ -327,7 +375,7 @@
6))
(try
(assert (= x 42)) ; This ain't true
(catch NameError e (assert e)))
(catch [e [NameError]] (assert e)))
(assert (= y 123)))