SF patch #1438387, PEP 328: relative and absolute imports.
- 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.
diff --git a/Python/compile.c b/Python/compile.c
index 9705ce4..78ae6a7 100644
--- a/Python/compile.c
+++ b/Python/compile.c
@@ -2452,10 +2452,22 @@
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 @@
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 @@
}
}
+ 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);