def _InitEnviron(self, environ):
# This is the way dash and bash work -- at startup, they turn everything in
# 'environ' variable into shell variables. Bash has an export_env
# variable. Dash has a loop through environ in init.c
for n, v in environ.iteritems():
self.SetVar(ast.LhsName(n), runtime.Str(v),
(var_flags.Exported,), scope.GlobalOnly)
def testShellFuncExecution(self):
ex = cmd_exec_test.InitExecutor()
func_node = ast.FuncDef()
c1 = ast.CompoundWord()
t1 = ast.token(Id.Lit_Chars, 'f1')
c1.parts.append(ast.LiteralPart(t1))
c2 = ast.CompoundWord()
t2 = ast.token(Id.Lit_Chars, 'f2')
c2.parts.append(ast.LiteralPart(t2))
a = ast.ArrayLiteralPart()
a.words = [c1, c2]
w = ast.CompoundWord()
w.parts.append(a)
# Set global COMPREPLY=(f1 f2)
pair = ast.assign_pair(ast.LhsName('COMPREPLY'), assign_op_e.Equal, w)
pair.spids.append(0) # dummy
pairs = [pair]
body_node = ast.Assignment(Id.Assign_None, [], pairs)
func_node.name = 'myfunc'
func_node.body = body_node
a = completion.ShellFuncAction(ex, func_node)
matches = list(a.Matches([], 0, 'f'))
self.assertEqual(['f1 ', 'f2 '], matches)
def SetLocalString(mem, name, s): """Set a local string. Used for: 1) for loop iteration variables 2) temporary environments like FOO=bar BAR=$FOO cmd, 3) read builtin """ assert isinstance(s, str) mem.SetVar(ast.LhsName(name), runtime.Str(s), (), scope.LocalOnly)
def _InitVarsFromEnv(self, environ):
# This is the way dash and bash work -- at startup, they turn everything in
# 'environ' variable into shell variables. Bash has an export_env
# variable. Dash has a loop through environ in init.c
for n, v in environ.iteritems():
self.SetVar(ast.LhsName(n), runtime.Str(v),
(var_flags_e.Exported,), scope_e.GlobalOnly)
# If it's not in the environment, initialize it. This makes it easier to
# update later in ExecOpts.
# TODO: IFS, PWD, etc. should follow this pattern. Maybe need a SysCall
# interface? self.syscall.getcwd() etc.
v = self.GetVar('SHELLOPTS')
if v.tag == value_e.Undef:
SetGlobalString(self, 'SHELLOPTS', '')
# Now make it readonly
self.SetVar(
ast.LhsName('SHELLOPTS'), None, (var_flags_e.ReadOnly,),
scope_e.GlobalOnly)
def ToLValue(node):
"""Determine if a node is a valid L-value by whitelisting tags.
Args:
node: ExprNode (could be VarExprNode or BinaryExprNode)
"""
# foo = bar, foo[1] = bar
if node.tag == arith_expr_e.ArithVarRef:
return ast.LhsName(node.name)
if node.tag == arith_expr_e.ArithBinary:
# For example, a[0][0] = 1 is NOT valid.
if (node.op_id == Id.Arith_LBracket
and node.left.tag == arith_expr_e.ArithVarRef):
return ast.LhsIndexedName(node.left.name, node.right)
return None
def ToLValue(node):
"""Determine if a node is a valid L-value by whitelisting tags.
Args:
node: ExprNode (could be VarExprNode or BinaryExprNode)
"""
# foo = bar, foo[1] = bar
if node.tag == arith_expr_e.ArithVarRef:
return ast.LhsName(node.name)
if node.tag == arith_expr_e.ArithBinary:
# For example, a[0][0] = 1 is NOT valid.
if (node.op_id == Id.Arith_LBracket
and node.left.tag == arith_expr_e.ArithVarRef):
return ast.LhsIndexedName(node.left.name, node.right)
# TODO: parse error context here.
raise TdopParseError("Can't assign to %r" % node)
def _EvalEnv(self, node_env, out_env):
"""Evaluate environment variable bindings.
Args:
node_env: list of ast.env_pair
out_env: mutated.
"""
# NOTE: Env evaluation is done in new scope so it doesn't persist. It also
# pushes argv. Don't need that?
self.mem.PushTemp()
for env_pair in node_env:
name = env_pair.name
rhs = env_pair.val
# Could pass extra bindings like out_env here? But PushTemp should work?
val = self.ev.EvalWordToString(rhs)
# Set each var so the next one can reference it. Example:
# FOO=1 BAR=$FOO ls /
self.mem.SetVar(ast.LhsName(name), val, (), scope.LocalOnly)
out_env[name] = val.s
self.mem.PopTemp()
def ParseSimpleCommand(self):
"""
Fixed transcription of the POSIX grammar (TODO: port to grammar/Shell.g)
io_file : '<' filename
| LESSAND filename
...
io_here : DLESS here_end
| DLESSDASH here_end
redirect : IO_NUMBER (io_redirect | io_here)
prefix_part : ASSIGNMENT_WORD | redirect
cmd_part : WORD | redirect
assign_kw : Declare | Export | Local | Readonly
# Without any words it is parsed as a command, not an assigment
assign_listing : assign_kw
# Now we have something to do (might be changing assignment flags too)
# NOTE: any prefixes should be a warning, but they are allowed in shell.
assignment : prefix_part* assign_kw (WORD | ASSIGNMENT_WORD)+
# an external command, a function call, or a builtin -- a "word_command"
word_command : prefix_part* cmd_part+
simple_command : assign_listing
| assignment
| proc_command
Simple imperative algorithm:
1) Read a list of words and redirects. Append them to separate lists.
2) Look for the first non-assignment word. If it's declare, etc., then
keep parsing words AND assign words. Otherwise, just parse words.
3) If there are no non-assignment words, then it's a global assignment.
{ redirects, global assignments } OR
{ redirects, prefix_bindings, words } OR
{ redirects, ERROR_prefix_bindings, keyword, assignments, words }
THEN CHECK that prefix bindings don't have any array literal parts!
global assignment and keyword assignments can have the of course.
well actually EXPORT shouldn't have them either -- WARNING
3 cases we want to warn: prefix_bindings for assignment, and array literal
in prefix bindings, or export
A command can be an assignment word, word, or redirect on its own.
ls
>out.txt
>out.txt FOO=bar # this touches the file, and hten
Or any sequence:
ls foo bar
<in.txt ls foo bar >out.txt
<in.txt ls >out.txt foo bar
Or add one or more environment bindings:
VAR=val env
>out.txt VAR=val env
here_end vs filename is a matter of whether we test that it's quoted. e.g.
<<EOF vs <<'EOF'.
"""
result = self._ScanSimpleCommand()
if not result: return None
redirects, words = result
if not words: # e.g. >out.txt # redirect without words
node = ast.SimpleCommand()
node.redirects = redirects
return node
prefix_bindings, suffix_words = self._SplitSimpleCommandPrefix(words)
if not suffix_words: # ONE=1 TWO=2 (with no other words)
if redirects:
binding1 = prefix_bindings[0]
_, _, _, spid = binding1
self.AddErrorContext('Got redirects in global assignment',
span_id=spid)
return None
pairs = []
for lhs, op, rhs, spid in prefix_bindings:
p = ast.assign_pair(ast.LhsName(lhs), op, rhs)
p.spids.append(spid)
pairs.append(p)
node = ast.Assignment(Id.Assign_None, [], pairs)
left_spid = word.LeftMostSpanForWord(words[0])
node.spids.append(left_spid) # no keyword spid to skip past
return node
kind, kw_token = word.KeywordToken(suffix_words[0])
if kind == Kind.Assign:
# Here we StaticEval suffix_words[1] to see if it's a command like
# 'typeset -p'. Then it becomes a SimpleCommand node instead of an
# Assignment. Note we're not handling duplicate flags like 'typeset
# -pf'. I see this in bashdb (bash debugger) but it can just be changed
# to 'typeset -p -f'.
is_command = False
if len(suffix_words) > 1:
ok, val, _ = word.StaticEval(suffix_words[1])
if ok and (kw_token.id, val) in self._ASSIGN_COMMANDS:
is_command = True
if is_command: # declare -f, declare -p, typeset -p, etc.
node = self._MakeSimpleCommand(prefix_bindings, suffix_words,
redirects)
return node
else: # declare str='', declare -a array=()
if redirects:
# Attach the error location to the keyword. It would be more precise
# to attach it to the
self.AddErrorContext('Got redirects in assignment', token=kw_token)
return None
if prefix_bindings: # FOO=bar local spam=eggs not allowed
# Use the location of the first value. TODO: Use the whole word before
# splitting.
_, _, v0, _ = prefix_bindings[0]
self.AddErrorContext(
'Invalid prefix bindings in assignment: %s', prefix_bindings,
word=v0)
return None
node = self._MakeAssignment(kw_token.id, suffix_words)
if not node: return None
node.spids.append(kw_token.span_id)
return node
elif kind == Kind.ControlFlow:
if redirects:
self.AddErrorContext('Got redirects in control flow: %s', redirects)
return None
if prefix_bindings: # FOO=bar local spam=eggs not allowed
# Use the location of the first value. TODO: Use the whole word before
# splitting.
_, _, v0, _ = prefix_bindings[0]
self.AddErrorContext(
'Invalid prefix bindings in control flow: %s', prefix_bindings,
word=v0)
return None
# Attach the token for errors. (Assignment may not need it.)
if len(suffix_words) == 1:
arg_word = None
elif len(suffix_words) == 2:
arg_word = suffix_words[1]
else:
self.AddErrorContext('Too many arguments')
return None
return ast.ControlFlow(kw_token, arg_word)
else:
node = self._MakeSimpleCommand(prefix_bindings, suffix_words, redirects)
return node
def _MakeAssignment(self, assign_kw, suffix_words):
# First parse flags, e.g. -r -x -a -A. None of the flags have arguments.
flags = []
n = len(suffix_words)
i = 1
while i < n:
w = suffix_words[i]
ok, static_val, quoted = word.StaticEval(w)
if not ok or quoted:
break # can't statically evaluate
if static_val.startswith('-'):
flags.append(static_val)
else:
break # not a flag, rest are args
i += 1
# Now parse bindings or variable names
assignments = []
while i < n:
w = suffix_words[i]
left_spid = word.LeftMostSpanForWord(w)
kov = word.LooksLikeAssignment(w)
if kov:
k, op, v = kov
t = word.TildeDetect(v)
if t:
# t is an unevaluated word with TildeSubPart
a = (k, op, t, left_spid)
else:
a = (k, op, v, left_spid) # v is unevaluated word
else:
# In aboriginal in variables/sources: export_if_blank does export "$1".
# We should allow that.
# Parse this differently then?
# dynamic-export?
# It sets global variables.
ok, static_val, quoted = word.StaticEval(w)
if not ok or quoted:
self.AddErrorContext(
'Variable names must be constant strings, got %s', w, word=w)
return None
# No value is equivalent to ''
m = VAR_NAME_RE.match(static_val)
if not m:
self.AddErrorContext('Invalid variable name %r', static_val, word=w)
return None
a = (static_val, assign_op_e.Equal, None, left_spid)
assignments.append(a)
i += 1
# TODO: Also make with LhsIndexedName
pairs = []
for lhs, op, rhs, spid in assignments:
p = ast.assign_pair(ast.LhsName(lhs), op, rhs)
p.spids.append(spid)
pairs.append(p)
node = ast.Assignment(assign_kw, flags, pairs)
return node
def SetGlobalArray(mem, name, a): """Helper for completion.""" assert isinstance(a, list) mem.SetVar(ast.LhsName(name), runtime.StrArray(a), (), scope.GlobalOnly)
def SetGlobalString(mem, name, s): """Helper for completion, $PWD, etc.""" assert isinstance(s, str) val = runtime.Str(s) mem.SetVar(ast.LhsName(name), val, (), scope.GlobalOnly)
