def _BindNewAssocArrayWithEntry(self, namespace, lval, value, new_flags):
"""Fill 'namespace' with a new indexed array entry."""
d = {lval.index: value.s} # TODO: RHS has to be string?
new_value = runtime.AssocArray(d)
# associative arrays can't be exported; don't need AssocArray flag
readonly = var_flags_e.ReadOnly in new_flags
namespace[lval.name] = runtime.cell(new_value, False, readonly, False)
def _BindNewArrayWithEntry(self, namespace, lval, value, new_flags):
"""Fill 'namespace' with a new indexed array entry."""
items = [None] * lval.index
items.append(value.s)
new_value = runtime.StrArray(items)
# arrays can't be exported; can't have AssocArray flag
readonly = var_flags_e.ReadOnly in new_flags
namespace[lval.name] = runtime.cell(new_value, False, readonly, False)
def SetVar(self, lval, value, new_flags, lookup_mode):
"""
Args:
lval: lvalue
val: value, or None if only changing flags
new_flags: tuple of flags to set: ReadOnly | Exported
() means no flags to start with
None means unchanged?
scope:
Local | Global | Dynamic - for builtins, PWD, etc.
NOTE: in bash, PWD=/ changes the directory. But not in dash.
"""
# STRICTNESS / SANENESS:
#
# 1) Don't create arrays automatically, e.g. a[1000]=x
# 2) Never change types? yeah I think that's a good idea, at least for oil
# (not sh, for compatibility). set -o strict-types or something. That
# means arrays have to be initialized with let arr = [], which is fine.
# This helps with stuff like IFS. It starts off as a string, and assigning
# it to a list is en error. I guess you will have to turn this no for
# bash?
assert new_flags is not None
if lval.tag == lvalue_e.LhsName:
#if lval.name == 'ldflags':
# TODO: Turn this into a tracing feature. Like osh --tracevar ldflags
# --tracevar foo. Has to respect environment variables too.
if 0:
util.log('--- SETTING ldflags to %s', value)
if lval.spids:
span_id = lval.spids[0]
line_span = self.arena.GetLineSpan(span_id)
line_id = line_span.line_id
#line = arena.GetLine(line_id)
path, line_num = self.arena.GetDebugInfo(line_id)
col = line_span.col
#length = line_span.length
util.log('--- spid %s: %s, line %d, col %d', span_id, path,
line_num + 1, col)
# TODO: Need the arena to look it up the line spid and line number.
# Maybe this should return one of (cell, scope). existing cell, or the
# scope to put it in?
# _FindCellOrScope
cell, namespace = self._FindCellAndNamespace(
lval.name, lookup_mode)
if cell:
if value is not None:
if cell.readonly:
# TODO: error context
e_die("Can't assign to readonly value %r", lval.name)
cell.val = value
if var_flags_e.Exported in new_flags:
cell.exported = True
if var_flags_e.ReadOnly in new_flags:
cell.readonly = True
else:
if value is None:
value = runtime.Undef() # export foo, readonly foo
cell = runtime.cell(value, var_flags_e.Exported in new_flags,
var_flags_e.ReadOnly in new_flags)
namespace[lval.name] = cell
if (cell.val is not None and cell.val.tag == value_e.StrArray
and cell.exported):
e_die("Can't export array") # TODO: error context
elif lval.tag == lvalue_e.LhsIndexedName:
# a[1]=(1 2 3)
if value.tag == value_e.StrArray:
e_die("Can't assign array to array member"
) # TODO: error context
cell, namespace = self._FindCellAndNamespace(
lval.name, lookup_mode)
if cell:
if cell.val.tag != value_e.StrArray:
# s=x
# s[1]=y
e_die("Can't index non-array") # TODO: error context
if cell.readonly:
e_die("Can't assign to readonly value")
strs = cell.val.strs
try:
strs[lval.index] = value.s
except IndexError:
# Fill it in with None. It could look like this:
# ['1', 2, 3, None, None, '4', None]
# Then ${#a[@]} counts the entries that are not None.
#
# TODO: strict-array for Oil arrays won't auto-fill.
n = lval.index - len(strs) + 1
strs.extend([None] * n)
strs[lval.index] = value.s
else:
# When the array doesn't exist yet, it is created filled with None.
# Access to the array needs to explicitly filter those sentinel values.
# It also wastes memory. But indexed access is fast.
# What should be optimized for? Bash uses a linked list. Random access
# takes linear time, but iteration skips unset entries automatically.
# - Maybe represent as hash table? Then it's not an ASDL type?
# representations:
# - array_item.Str array_item.Undef
# - parallel array: val.strs, val.undefs
# - or change ASDL type checking
# - ASDL language does not allow: StrArray(string?* strs)
# - or add dict to ASDL? Didn't it support obj?
# - finding the max index is linear time?
# - also you have to sort the indices
#
# array ops:
# a=(1 2)
# a[1]=x
# a+=(1 2)
# ${a[@]} - get all
# ${#a[@]} - length
# ${!a[@]} - keys
# That seems pretty minimal.
items = [None] * lval.index
items.append(value.s)
new_value = runtime.StrArray(items)
# arrays can't be exported
cell = runtime.cell(new_value, False, var_flags_e.ReadOnly
in new_flags)
namespace[lval.name] = cell
else:
raise AssertionError
def SetVar(self, lval, value, new_flags, lookup_mode, strict_array=False):
"""
Args:
lval: lvalue
val: value, or None if only changing flags
new_flags: tuple of flags to set: ReadOnly | Exported
() means no flags to start with
None means unchanged?
scope:
Local | Global | Dynamic - for builtins, PWD, etc.
NOTE: in bash, PWD=/ changes the directory. But not in dash.
"""
# STRICTNESS / SANENESS:
#
# 1) Don't create arrays automatically, e.g. a[1000]=x
# 2) Never change types? yeah I think that's a good idea, at least for oil
# (not sh, for compatibility). set -o strict-types or something. That
# means arrays have to be initialized with let arr = [], which is fine.
# This helps with stuff like IFS. It starts off as a string, and assigning
# it to a list is en error. I guess you will have to turn this no for
# bash?
assert new_flags is not None
if lval.tag == lvalue_e.LhsName:
#if lval.name == 'ldflags':
# TODO: Turn this into a tracing feature. Like osh --tracevar ldflags
# --tracevar foo. Has to respect environment variables too.
if 0:
util.log('--- SETTING ldflags to %s', value)
if lval.spids:
span_id = lval.spids[0]
line_span = self.arena.GetLineSpan(span_id)
line_id = line_span.line_id
#line = arena.GetLine(line_id)
path, line_num = self.arena.GetDebugInfo(line_id)
col = line_span.col
#length = line_span.length
util.log('--- spid %s: %s, line %d, col %d', span_id, path,
line_num + 1, col)
# TODO: Need the arena to look it up the line spid and line number.
# Maybe this should return one of (cell, scope). existing cell, or the
# scope to put it in?
# _FindCellOrScope
cell, namespace = self._FindCellAndNamespace(
lval.name, lookup_mode)
if cell:
if value is not None:
if cell.readonly:
# TODO: error context
e_die("Can't assign to readonly value %r", lval.name)
cell.val = value
if var_flags_e.Exported in new_flags:
cell.exported = True
if var_flags_e.ReadOnly in new_flags:
cell.readonly = True
if var_flags_e.AssocArray in new_flags:
cell.is_assoc_array = True
else:
if value is None:
# set -o nounset; local foo; echo $foo # It's still undefined!
value = runtime.Undef() # export foo, readonly foo
cell = runtime.cell(value, var_flags_e.Exported in new_flags,
var_flags_e.ReadOnly in new_flags,
var_flags_e.AssocArray in new_flags)
namespace[lval.name] = cell
if (cell.val is not None and cell.val.tag == value_e.StrArray
and cell.exported):
e_die("Can't export array") # TODO: error context
elif lval.tag == lvalue_e.LhsIndexedName:
# TODO: All paths should have this? We can get here by a[x]=1 or
# (( a[ x ] = 1 )). Maybe we should make them different?
if lval.spids:
left_spid = lval.spids[0]
else:
left_spid = const.NO_INTEGER
# TODO: This is a parse error!
# a[1]=(1 2 3)
if value.tag == value_e.StrArray:
e_die("Can't assign array to array member", span_id=left_spid)
cell, namespace = self._FindCellAndNamespace(
lval.name, lookup_mode)
if not cell:
self._BindNewArrayWithEntry(namespace, lval, value, new_flags)
return
# bash/mksh have annoying behavior of letting you do LHS assignment to
# Undef, which then turns into an array. (Undef means that set -o
# nounset fails.)
cell_tag = cell.val.tag
if (cell_tag == value_e.Str
or (cell_tag == value_e.Undef and strict_array)):
# s=x
# s[1]=y # invalid
e_die("Entries in value of type %s can't be assigned to",
cell.val.__class__.__name__,
span_id=left_spid)
if cell.readonly:
e_die("Can't assign to readonly value", span_id=left_spid)
if cell_tag == value_e.Undef:
if cell.is_assoc_array:
self._BindNewAssocArrayWithEntry(namespace, lval, value,
new_flags)
else:
self._BindNewArrayWithEntry(namespace, lval, value,
new_flags)
return
if cell_tag == value_e.StrArray:
strs = cell.val.strs
try:
strs[lval.index] = value.s
except IndexError:
# Fill it in with None. It could look like this:
# ['1', 2, 3, None, None, '4', None]
# Then ${#a[@]} counts the entries that are not None.
#
# TODO: strict-array for Oil arrays won't auto-fill.
n = lval.index - len(strs) + 1
strs.extend([None] * n)
strs[lval.index] = value.s
return
if cell_tag == value_e.AssocArray:
cell.val.d[lval.index] = value.s
return
else:
raise AssertionError(lval.__class__.__name__)