mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-08-30 13:38:43 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 8

SF patch #1438387, PEP 328: relative and absolute imports.

Browse source 
- IMPORT_NAME takes an extra argument from the stack: the relativeness of
   the import. Only passed to __import__ when it's not -1.

 - __import__() takes an optional 5th argument for the same thing; it
   __defaults to -1 (old semantics: try relative, then absolute)

 - 'from . import name' imports name (be it module or regular attribute)
   from the current module's *package*. Likewise, 'from .module import name'
   will import name from a sibling to the current module.

 - Importing from outside a package is not allowed; 'from . import sys' in a
   toplevel module will not work, nor will 'from .. import sys' in a
   (single-level) package.

 - 'from __future__ import absolute_import' will turn on the new semantics
   for import and from-import: imports will be absolute, except for
   from-import with dots.

Includes tests for regular imports and importhooks, parser changes and a
NEWS item, but no compiler-package changes or documentation changes.
This commit is contained in:
Thomas Wouters 2006-02-28 16:09:29 +00:00
parent d3188639c3
commit f7f438ba3b
20 changed files with 270 additions and 73 deletions
Download patch file Download diff file Expand all files Collapse all files

12
Python/Python-ast.c
View file

@ -120,6 +120,7 @@ PyTypeObject *ImportFrom_type;
char *ImportFrom_fields[]={
"module",
"names",
"level",
};
PyTypeObject *Exec_type;
char *Exec_fields[]={
@ -485,7 +486,7 @@ static int init_types(void)
Import_type = make_type("Import", stmt_type, Import_fields, 1);
if (!Import_type) return 0;
ImportFrom_type = make_type("ImportFrom", stmt_type, ImportFrom_fields,
2);
3);
if (!ImportFrom_type) return 0;
Exec_type = make_type("Exec", stmt_type, Exec_fields, 3);
if (!Exec_type) return 0;
@ -1118,7 +1119,8 @@ Import(asdl_seq * names, int lineno, PyArena *arena)
}
stmt_ty
ImportFrom(identifier module, asdl_seq * names, int lineno, PyArena *arena)
ImportFrom(identifier module, asdl_seq * names, int level, int lineno, PyArena
*arena)
{
stmt_ty p;
if (!module) {
@ -1134,6 +1136,7 @@ ImportFrom(identifier module, asdl_seq * names, int lineno, PyArena *arena)
p->kind = ImportFrom_kind;
p->v.ImportFrom.module = module;
p->v.ImportFrom.names = names;
p->v.ImportFrom.level = level;
p->lineno = lineno;
return p;
}
@ -2202,6 +2205,11 @@ ast2obj_stmt(void* _o)
if (PyObject_SetAttrString(result, "names", value) == -1)
goto failed;
Py_DECREF(value);
value = ast2obj_int(o->v.ImportFrom.level);
if (!value) goto failed;
if (PyObject_SetAttrString(result, "level", value) == -1)
goto failed;
Py_DECREF(value);
break;
case Exec_kind:
result = PyType_GenericNew(Exec_type, NULL, NULL);

45
Python/ast.c
View file

@ -2171,9 +2171,8 @@ ast_for_import_stmt(struct compiling *c, const node *n)
/*
import_stmt: import_name | import_from
import_name: 'import' dotted_as_names
import_from: 'from' dotted_name 'import' ('*' |
'(' import_as_names ')' |
import_as_names)
import_from: 'from' ('.'* dotted_name | '.') 'import'
('*' | '(' import_as_names ')' | import_as_names)
*/
int i;
asdl_seq *aliases;
@ -2197,24 +2196,41 @@ ast_for_import_stmt(struct compiling *c, const node *n)
else if (TYPE(n) == import_from) {
int n_children;
int lineno = LINENO(n);
alias_ty mod = alias_for_import_name(c, CHILD(n, 1));
if (!mod)
return NULL;
switch (TYPE(CHILD(n, 3))) {
int idx, ndots = 0;
alias_ty mod = NULL;
identifier modname;
/* Count the number of dots (for relative imports) and check for the
optional module name */
for (idx = 1; idx < NCH(n); idx++) {
if (TYPE(CHILD(n, idx)) == dotted_name) {
mod = alias_for_import_name(c, CHILD(n, idx));
idx++;
break;
} else if (TYPE(CHILD(n, idx)) != DOT) {
break;
}
ndots++;
}
idx++; /* skip over the 'import' keyword */
switch (TYPE(CHILD(n, idx))) {
case STAR:
/* from ... import * */
n = CHILD(n, 3);
n = CHILD(n, idx);
n_children = 1;
if (ndots) {
ast_error(n, "'import *' not allowed with 'from .'");
return NULL;
}
break;
case LPAR:
/* from ... import (x, y, z) */
n = CHILD(n, 4);
n = CHILD(n, idx + 1);
n_children = NCH(n);
break;
case import_as_names:
/* from ... import x, y, z */
n = CHILD(n, 3);
n = CHILD(n, idx);
n_children = NCH(n);
if (n_children % 2 == 0) {
ast_error(n, "trailing comma not allowed without"
@ -2245,7 +2261,12 @@ ast_for_import_stmt(struct compiling *c, const node *n)
return NULL;
asdl_seq_APPEND(aliases, import_alias);
}
return ImportFrom(mod->name, aliases, lineno, c->c_arena);
if (mod != NULL)
modname = mod->name;
else
modname = new_identifier("", c->c_arena);
return ImportFrom(modname, aliases, ndots, lineno,
c->c_arena);
}
PyErr_Format(PyExc_SystemError,
"unknown import statement: starts with command '%s'",

8
Python/bltinmodule.c
View file

@ -37,11 +37,13 @@ builtin___import__(PyObject *self, PyObject *args)
PyObject *globals = NULL;
PyObject *locals = NULL;
PyObject *fromlist = NULL;
int level = -1;
if (!PyArg_ParseTuple(args, "s|OOO:__import__",
&name, &globals, &locals, &fromlist))
if (!PyArg_ParseTuple(args, "s|OOOi:__import__",
&name, &globals, &locals, &fromlist, &level))
return NULL;
return PyImport_ImportModuleEx(name, globals, locals, fromlist);
return PyImport_ImportModuleLevel(name, globals, locals,
fromlist, level);
}
PyDoc_STRVAR(import_doc,

23
Python/ceval.c
View file

@ -2023,13 +2023,24 @@ PyEval_EvalFrameEx(PyFrameObject *f, int throw)
"__import__ not found");
break;
}
v = POP();
u = TOP();
w = PyTuple_Pack(4,
w,
f->f_globals,
f->f_locals == NULL ?
Py_None : f->f_locals,
u);
if (PyInt_AsLong(u) != -1 || PyErr_Occurred())
w = PyTuple_Pack(5,
w,
f->f_globals,
f->f_locals == NULL ?
Py_None : f->f_locals,
v,
u);
else
w = PyTuple_Pack(4,
w,
f->f_globals,
f->f_locals == NULL ?
Py_None : f->f_locals,
v);
Py_DECREF(v);
Py_DECREF(u);
if (w == NULL) {
u = POP();

2
Python/codecs.c
View file

@ -831,7 +831,7 @@ static int _PyCodecRegistry_Init(void)
interp->codec_error_registry == NULL)
Py_FatalError("can't initialize codec registry");
mod = PyImport_ImportModuleEx("encodings", NULL, NULL, NULL);
mod = PyImport_ImportModuleLevel("encodings", NULL, NULL, NULL, 0);
if (mod == NULL) {
if (PyErr_ExceptionMatches(PyExc_ImportError)) {
/* Ignore ImportErrors... this is done so that

27
Python/compile.c
View file

@ -2452,10 +2452,22 @@ compiler_import(struct compiler *c, stmt_ty s)
XXX Perhaps change the representation to make this case simpler?
*/
int i, n = asdl_seq_LEN(s->v.Import.names);
for (i = 0; i < n; i++) {
alias_ty alias = asdl_seq_GET(s->v.Import.names, i);
int r;
PyObject *level;
if (c->c_flags && (c->c_flags->cf_flags & CO_FUTURE_ABSIMPORT))
level = PyInt_FromLong(0);
else
level = PyInt_FromLong(-1);
if (level == NULL)
return 0;
ADDOP_O(c, LOAD_CONST, level, consts);
Py_DECREF(level);
ADDOP_O(c, LOAD_CONST, Py_None, consts);
ADDOP_NAME(c, IMPORT_NAME, alias->name, names);
@ -2488,9 +2500,22 @@ compiler_from_import(struct compiler *c, stmt_ty s)
int i, n = asdl_seq_LEN(s->v.ImportFrom.names);
PyObject *names = PyTuple_New(n);
PyObject *level;
if (!names)
return 0;
if (s->v.ImportFrom.level == 0 && c->c_flags &&
!(c->c_flags->cf_flags & CO_FUTURE_ABSIMPORT))
level = PyInt_FromLong(-1);
else
level = PyInt_FromLong(s->v.ImportFrom.level);
if (!level) {
Py_DECREF(names);
return 0;
}
/* build up the names */
for (i = 0; i < n; i++) {
alias_ty alias = asdl_seq_GET(s->v.ImportFrom.names, i);
@ -2509,6 +2534,8 @@ compiler_from_import(struct compiler *c, stmt_ty s)
}
}
ADDOP_O(c, LOAD_CONST, level, consts);
Py_DECREF(level);
ADDOP_O(c, LOAD_CONST, names, consts);
Py_DECREF(names);
ADDOP_NAME(c, IMPORT_NAME, s->v.ImportFrom.module, names);

2
Python/future.c
View file

@ -29,6 +29,8 @@ future_check_features(PyFutureFeatures *ff, stmt_ty s, const char *filename)
continue;
} else if (strcmp(feature, FUTURE_DIVISION) == 0) {
ff->ff_features |= CO_FUTURE_DIVISION;
} else if (strcmp(feature, FUTURE_ABSIMPORT) == 0) {
ff->ff_features |= CO_FUTURE_ABSIMPORT;
} else if (strcmp(feature, "braces") == 0) {
PyErr_SetString(PyExc_SyntaxError,
"not a chance");

47
Python/graminit.c
View file

@ -513,34 +513,45 @@ static arc arcs_26_0[1] = {
{74, 1},
};
static arc arcs_26_1[2] = {
{75, 1},
{12, 2},
{75, 2},
{12, 3},
};
static arc arcs_26_2[1] = {
{72, 3},
static arc arcs_26_2[3] = {
{75, 4},
{12, 3},
{72, 5},
};
static arc arcs_26_3[3] = {
{28, 4},
{13, 5},
{76, 4},
static arc arcs_26_3[1] = {
{72, 5},
};
static arc arcs_26_4[1] = {
{0, 4},
static arc arcs_26_4[2] = {
{75, 4},
{12, 3},
};
static arc arcs_26_5[1] = {
static arc arcs_26_5[3] = {
{28, 6},
{13, 7},
{76, 6},
};
static arc arcs_26_6[1] = {
{15, 4},
{0, 6},
};
static state states_26[7] = {
static arc arcs_26_7[1] = {
{76, 8},
};
static arc arcs_26_8[1] = {
{15, 6},
};
static state states_26[9] = {
{1, arcs_26_0},
{2, arcs_26_1},
{1, arcs_26_2},
{3, arcs_26_3},
{1, arcs_26_4},
{1, arcs_26_5},
{3, arcs_26_2},
{1, arcs_26_3},
{2, arcs_26_4},
{3, arcs_26_5},
{1, arcs_26_6},
{1, arcs_26_7},
{1, arcs_26_8},
};
static arc arcs_27_0[1] = {
{19, 1},
@ -1825,7 +1836,7 @@ static dfa dfas[84] = {
"\000\000\000\000\000\000\000\000\000\005\000\000\000\000\000\000\000\000\000\000\000"},
{281, "import_name", 0, 3, states_25,
"\000\000\000\000\000\000\000\000\000\001\000\000\000\000\000\000\000\000\000\000\000"},
{282, "import_from", 0, 7, states_26,
{282, "import_from", 0, 9, states_26,
"\000\000\000\000\000\000\000\000\000\004\000\000\000\000\000\000\000\000\000\000\000"},
{283, "import_as_name", 0, 4, states_27,
"\000\000\010\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000"},

69
Python/import.c
View file

@ -57,7 +57,7 @@ extern time_t PyOS_GetLastModificationTime(char *, FILE *);
Python 2.5a0: 62091 (with)
.
*/
#define MAGIC (62091 | ((long)'\r'<<16) | ((long)'\n'<<24))
#define MAGIC (62092 | ((long)'\r'<<16) | ((long)'\n'<<24))
/* Magic word as global; note that _PyImport_Init() can change the
value of this global to accommodate for alterations of how the
@ -1894,7 +1894,8 @@ PyImport_ImportModule(const char *name)
}
/* Forward declarations for helper routines */
static PyObject *get_parent(PyObject *globals, char *buf, Py_ssize_t *p_buflen);
static PyObject *get_parent(PyObject *globals, char *buf,
Py_ssize_t *p_buflen, int level);
static PyObject *load_next(PyObject *mod, PyObject *altmod,
char **p_name, char *buf, Py_ssize_t *p_buflen);
static int mark_miss(char *name);
@ -1905,14 +1906,14 @@ static PyObject * import_submodule(PyObject *mod, char *name, char *fullname);
/* The Magnum Opus of dotted-name import :-) */
static PyObject *
import_module_ex(char *name, PyObject *globals, PyObject *locals,
PyObject *fromlist)
import_module_level(char *name, PyObject *globals, PyObject *locals,
PyObject *fromlist, int level)
{
char buf[MAXPATHLEN+1];
Py_ssize_t buflen = 0;
PyObject *parent, *head, *next, *tail;
parent = get_parent(globals, buf, &buflen);
parent = get_parent(globals, buf, &buflen, level);
if (parent == NULL)
return NULL;
@ -1951,13 +1952,33 @@ import_module_ex(char *name, PyObject *globals, PyObject *locals,
return tail;
}
/* For DLL compatibility */
#undef PyImport_ImportModuleEx
PyObject *
PyImport_ImportModuleEx(char *name, PyObject *globals, PyObject *locals,
PyObject *fromlist)
{
PyObject *result;
lock_import();
result = import_module_ex(name, globals, locals, fromlist);
result = import_module_level(name, globals, locals, fromlist, -1);
if (unlock_import() < 0) {
Py_XDECREF(result);
PyErr_SetString(PyExc_RuntimeError,
"not holding the import lock");
return NULL;
}
return result;
}
#define PyImport_ImportModuleEx(n, g, l, f) \
PyImport_ImportModuleLevel(n, g, l, f, -1);
PyObject *
PyImport_ImportModuleLevel(char *name, PyObject *globals, PyObject *locals,
PyObject *fromlist, int level)
{
PyObject *result;
lock_import();
result = import_module_level(name, globals, locals, fromlist, level);
if (unlock_import() < 0) {
Py_XDECREF(result);
PyErr_SetString(PyExc_RuntimeError,
@ -1979,13 +2000,13 @@ PyImport_ImportModuleEx(char *name, PyObject *globals, PyObject *locals,
corresponding entry is not found in sys.modules, Py_None is returned.
*/
static PyObject *
get_parent(PyObject *globals, char *buf, Py_ssize_t *p_buflen)
get_parent(PyObject *globals, char *buf, Py_ssize_t *p_buflen, int level)
{
static PyObject *namestr = NULL;
static PyObject *pathstr = NULL;
PyObject *modname, *modpath, *modules, *parent;
if (globals == NULL || !PyDict_Check(globals))
if (globals == NULL || !PyDict_Check(globals) || !level)
return Py_None;
if (namestr == NULL) {
@ -2014,12 +2035,16 @@ get_parent(PyObject *globals, char *buf, Py_ssize_t *p_buflen)
return NULL;
}
strcpy(buf, PyString_AS_STRING(modname));
*p_buflen = len;
}
else {
char *start = PyString_AS_STRING(modname);
char *lastdot = strrchr(start, '.');
size_t len;
if (lastdot == NULL && level > 0) {
PyErr_SetString(PyExc_ValueError,
"Relative importpath too deep");
return NULL;
}
if (lastdot == NULL)
return Py_None;
len = lastdot - start;
@ -2030,13 +2055,24 @@ get_parent(PyObject *globals, char *buf, Py_ssize_t *p_buflen)
}
strncpy(buf, start, len);
buf[len] = '\0';
*p_buflen = len;
}
while (--level > 0) {
char *dot = strrchr(buf, '.');
if (dot == NULL) {
PyErr_SetString(PyExc_ValueError,
"Relative importpath too deep");
return NULL;
}
*dot = '\0';
}
*p_buflen = strlen(buf);
modules = PyImport_GetModuleDict();
parent = PyDict_GetItemString(modules, buf);
if (parent == NULL)
parent = Py_None;
PyErr_Format(PyExc_SystemError,
"Parent module '%.200s' not loaded", buf);
return parent;
/* We expect, but can't guarantee, if parent != None, that:
- parent.__name__ == buf
@ -2055,6 +2091,13 @@ load_next(PyObject *mod, PyObject *altmod, char **p_name, char *buf,
char *p;
PyObject *result;
if (strlen(name) == 0) {
/* empty module name only happens in 'from . import' */
Py_INCREF(mod);
*p_name = NULL;
return mod;
}
if (dot == NULL) {
*p_name = NULL;
len = strlen(name);
@ -2396,8 +2439,8 @@ PyImport_Import(PyObject *module_name)
/* No globals -- use standard builtins, and fake globals */
PyErr_Clear();
builtins = PyImport_ImportModuleEx("__builtin__",
NULL, NULL, NULL);
builtins = PyImport_ImportModuleLevel("__builtin__",
NULL, NULL, NULL, 0);
if (builtins == NULL)
return NULL;
globals = Py_BuildValue("{OO}", builtins_str, builtins);