py, compiler: Implement compiling of relative imports.
diff --git a/py/compile.c b/py/compile.c
index 3ea6dd3..4bee549 100644
--- a/py/compile.c
+++ b/py/compile.c
@@ -1236,31 +1236,35 @@
}
}
-// q1 holds the base, q2 the full name
-// eg a -> q1=q2=a
-// a.b.c -> q1=a, q2=a.b.c
-void do_import_name(compiler_t *comp, mp_parse_node_t pn, qstr *q1, qstr *q2) {
+// q_base holds the base of the name
+// eg a -> q_base=a
+// a.b.c -> q_base=a
+void do_import_name(compiler_t *comp, mp_parse_node_t pn, qstr *q_base) {
bool is_as = false;
if (MP_PARSE_NODE_IS_STRUCT_KIND(pn, PN_dotted_as_name)) {
mp_parse_node_struct_t *pns = (mp_parse_node_struct_t*)pn;
// a name of the form x as y; unwrap it
- *q1 = MP_PARSE_NODE_LEAF_ARG(pns->nodes[1]);
+ *q_base = MP_PARSE_NODE_LEAF_ARG(pns->nodes[1]);
pn = pns->nodes[0];
is_as = true;
}
- if (MP_PARSE_NODE_IS_ID(pn)) {
+ if (MP_PARSE_NODE_IS_NULL(pn)) {
+ // empty name (eg, from . import x)
+ *q_base = MP_QSTR_;
+ EMIT_ARG(import_name, MP_QSTR_); // import the empty string
+ } else if (MP_PARSE_NODE_IS_ID(pn)) {
// just a simple name
- *q2 = MP_PARSE_NODE_LEAF_ARG(pn);
+ qstr q_full = MP_PARSE_NODE_LEAF_ARG(pn);
if (!is_as) {
- *q1 = *q2;
+ *q_base = q_full;
}
- EMIT_ARG(import_name, *q2);
+ EMIT_ARG(import_name, q_full);
} else if (MP_PARSE_NODE_IS_STRUCT(pn)) {
mp_parse_node_struct_t *pns = (mp_parse_node_struct_t*)pn;
if (MP_PARSE_NODE_STRUCT_KIND(pns) == PN_dotted_name) {
// a name of the form a.b.c
if (!is_as) {
- *q1 = MP_PARSE_NODE_LEAF_ARG(pns->nodes[0]);
+ *q_base = MP_PARSE_NODE_LEAF_ARG(pns->nodes[0]);
}
int n = MP_PARSE_NODE_STRUCT_NUM_NODES(pns);
int len = n - 1;
@@ -1278,33 +1282,29 @@
memcpy(str_dest, str_src, str_src_len);
str_dest += str_src_len;
}
- *q2 = qstr_build_end(q_ptr);
- EMIT_ARG(import_name, *q2);
+ qstr q_full = qstr_build_end(q_ptr);
+ EMIT_ARG(import_name, q_full);
if (is_as) {
for (int i = 1; i < n; i++) {
EMIT_ARG(load_attr, MP_PARSE_NODE_LEAF_ARG(pns->nodes[i]));
}
}
} else {
- // TODO not implemented
- // This covers relative imports starting with dot(s) like "from .foo import"
- compile_syntax_error(comp, pn, "Relative imports not implemented");
- return;
+ // shouldn't happen
+ assert(0);
}
} else {
- // TODO not implemented
- // This covers relative imports with dots only like "from .. import"
- compile_syntax_error(comp, pn, "Relative imports not implemented");
- return;
+ // shouldn't happen
+ assert(0);
}
}
void compile_dotted_as_name(compiler_t *comp, mp_parse_node_t pn) {
- EMIT_ARG(load_const_small_int, 0); // ??
- EMIT_ARG(load_const_tok, MP_TOKEN_KW_NONE);
- qstr q1, q2;
- do_import_name(comp, pn, &q1, &q2);
- EMIT_ARG(store_id, q1);
+ EMIT_ARG(load_const_small_int, 0); // level 0 import
+ EMIT_ARG(load_const_tok, MP_TOKEN_KW_NONE); // not importing from anything
+ qstr q_base;
+ do_import_name(comp, pn, &q_base);
+ EMIT_ARG(store_id, q_base);
}
void compile_import_name(compiler_t *comp, mp_parse_node_struct_t *pns) {
@@ -1312,8 +1312,44 @@
}
void compile_import_from(compiler_t *comp, mp_parse_node_struct_t *pns) {
+ mp_parse_node_t pn_import_source = pns->nodes[0];
+
+ // extract the preceeding .'s (if any) for a relative import, to compute the import level
+ uint import_level = 0;
+ do {
+ mp_parse_node_t pn_rel;
+ if (MP_PARSE_NODE_IS_TOKEN(pn_import_source) || MP_PARSE_NODE_IS_STRUCT_KIND(pn_import_source, PN_one_or_more_period_or_ellipsis)) {
+ // This covers relative imports with dots only like "from .. import"
+ pn_rel = pn_import_source;
+ pn_import_source = MP_PARSE_NODE_NULL;
+ } else if (MP_PARSE_NODE_IS_STRUCT_KIND(pn_import_source, PN_import_from_2b)) {
+ // This covers relative imports starting with dot(s) like "from .foo import"
+ mp_parse_node_struct_t *pns_2b = (mp_parse_node_struct_t*)pn_import_source;
+ pn_rel = pns_2b->nodes[0];
+ pn_import_source = pns_2b->nodes[1];
+ assert(!MP_PARSE_NODE_IS_NULL(pn_import_source)); // should not be
+ } else {
+ // Not a relative import
+ break;
+ }
+
+ // get the list of . and/or ...'s
+ mp_parse_node_t *nodes;
+ int n = list_get(&pn_rel, PN_one_or_more_period_or_ellipsis, &nodes);
+
+ // count the total number of .'s
+ for (int i = 0; i < n; i++) {
+ if (MP_PARSE_NODE_IS_TOKEN_KIND(nodes[i], MP_TOKEN_DEL_PERIOD)) {
+ import_level++;
+ } else {
+ // should be an MP_TOKEN_ELLIPSIS
+ import_level += 3;
+ }
+ }
+ } while (0);
+
if (MP_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], MP_TOKEN_OP_STAR)) {
- EMIT_ARG(load_const_small_int, 0); // level 0 for __import__
+ EMIT_ARG(load_const_small_int, import_level);
// build the "fromlist" tuple
#if MICROPY_EMIT_CPYTHON
@@ -1324,12 +1360,12 @@
#endif
// do the import
- qstr dummy_q, id1;
- do_import_name(comp, pns->nodes[0], &dummy_q, &id1);
+ qstr dummy_q;
+ do_import_name(comp, pn_import_source, &dummy_q);
EMIT(import_star);
} else {
- EMIT_ARG(load_const_small_int, 0); // level 0 for __import__
+ EMIT_ARG(load_const_small_int, import_level);
// build the "fromlist" tuple
mp_parse_node_t *pn_nodes;
@@ -1369,8 +1405,8 @@
#endif
// do the import
- qstr dummy_q, id1;
- do_import_name(comp, pns->nodes[0], &dummy_q, &id1);
+ qstr dummy_q;
+ do_import_name(comp, pn_import_source, &dummy_q);
for (int i = 0; i < n; i++) {
assert(MP_PARSE_NODE_IS_STRUCT_KIND(pn_nodes[i], PN_import_as_name));
mp_parse_node_struct_t *pns3 = (mp_parse_node_struct_t*)pn_nodes[i];