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authormonster <monster@ydb.tech>2022-07-07 14:41:37 +0300
committermonster <monster@ydb.tech>2022-07-07 14:41:37 +0300
commit06e5c21a835c0e923506c4ff27929f34e00761c2 (patch)
tree75efcbc6854ef9bd476eb8bf00cc5c900da436a2 /contrib/tools/python3/src/Python/suggestions.c
parent03f024c4412e3aa613bb543cf1660176320ba8f4 (diff)
downloadydb-06e5c21a835c0e923506c4ff27929f34e00761c2.tar.gz
fix ya.make
Diffstat (limited to 'contrib/tools/python3/src/Python/suggestions.c')
-rw-r--r--contrib/tools/python3/src/Python/suggestions.c289
1 files changed, 0 insertions, 289 deletions
diff --git a/contrib/tools/python3/src/Python/suggestions.c b/contrib/tools/python3/src/Python/suggestions.c
deleted file mode 100644
index 4e2f905577..0000000000
--- a/contrib/tools/python3/src/Python/suggestions.c
+++ /dev/null
@@ -1,289 +0,0 @@
-#include "Python.h"
-#include "frameobject.h"
-
-#include "pycore_pyerrors.h"
-
-#define MAX_CANDIDATE_ITEMS 750
-#define MAX_STRING_SIZE 40
-
-#define MOVE_COST 2
-#define CASE_COST 1
-
-#define LEAST_FIVE_BITS(n) ((n) & 31)
-
-static inline int
-substitution_cost(char a, char b)
-{
- if (LEAST_FIVE_BITS(a) != LEAST_FIVE_BITS(b)) {
- // Not the same, not a case flip.
- return MOVE_COST;
- }
- if (a == b) {
- return 0;
- }
- if ('A' <= a && a <= 'Z') {
- a += ('a' - 'A');
- }
- if ('A' <= b && b <= 'Z') {
- b += ('a' - 'A');
- }
- if (a == b) {
- return CASE_COST;
- }
- return MOVE_COST;
-}
-
-/* Calculate the Levenshtein distance between string1 and string2 */
-static Py_ssize_t
-levenshtein_distance(const char *a, size_t a_size,
- const char *b, size_t b_size,
- size_t max_cost)
-{
- static size_t buffer[MAX_STRING_SIZE];
-
- // Both strings are the same (by identity)
- if (a == b) {
- return 0;
- }
-
- // Trim away common affixes.
- while (a_size && b_size && a[0] == b[0]) {
- a++; a_size--;
- b++; b_size--;
- }
- while (a_size && b_size && a[a_size-1] == b[b_size-1]) {
- a_size--;
- b_size--;
- }
- if (a_size == 0 || b_size == 0) {
- return (a_size + b_size) * MOVE_COST;
- }
- if (a_size > MAX_STRING_SIZE || b_size > MAX_STRING_SIZE) {
- return max_cost + 1;
- }
-
- // Prefer shorter buffer
- if (b_size < a_size) {
- const char *t = a; a = b; b = t;
- size_t t_size = a_size; a_size = b_size; b_size = t_size;
- }
-
- // quick fail when a match is impossible.
- if ((b_size - a_size) * MOVE_COST > max_cost) {
- return max_cost + 1;
- }
-
- // Instead of producing the whole traditional len(a)-by-len(b)
- // matrix, we can update just one row in place.
- // Initialize the buffer row
- for (size_t i = 0; i < a_size; i++) {
- // cost from b[:0] to a[:i+1]
- buffer[i] = (i + 1) * MOVE_COST;
- }
-
- size_t result = 0;
- for (size_t b_index = 0; b_index < b_size; b_index++) {
- char code = b[b_index];
- // cost(b[:b_index], a[:0]) == b_index * MOVE_COST
- size_t distance = result = b_index * MOVE_COST;
- size_t minimum = SIZE_MAX;
- for (size_t index = 0; index < a_size; index++) {
-
- // cost(b[:b_index+1], a[:index+1]) = min(
- // // 1) substitute
- // cost(b[:b_index], a[:index])
- // + substitution_cost(b[b_index], a[index]),
- // // 2) delete from b
- // cost(b[:b_index], a[:index+1]) + MOVE_COST,
- // // 3) delete from a
- // cost(b[:b_index+1], a[index]) + MOVE_COST
- // )
-
- // 1) Previous distance in this row is cost(b[:b_index], a[:index])
- size_t substitute = distance + substitution_cost(code, a[index]);
- // 2) cost(b[:b_index], a[:index+1]) from previous row
- distance = buffer[index];
- // 3) existing result is cost(b[:b_index+1], a[index])
-
- size_t insert_delete = Py_MIN(result, distance) + MOVE_COST;
- result = Py_MIN(insert_delete, substitute);
-
- // cost(b[:b_index+1], a[:index+1])
- buffer[index] = result;
- if (result < minimum) {
- minimum = result;
- }
- }
- if (minimum > max_cost) {
- // Everything in this row is too big, so bail early.
- return max_cost + 1;
- }
- }
- return result;
-}
-
-static inline PyObject *
-calculate_suggestions(PyObject *dir,
- PyObject *name)
-{
- assert(!PyErr_Occurred());
- assert(PyList_CheckExact(dir));
-
- Py_ssize_t dir_size = PyList_GET_SIZE(dir);
- if (dir_size >= MAX_CANDIDATE_ITEMS) {
- return NULL;
- }
-
- Py_ssize_t suggestion_distance = PY_SSIZE_T_MAX;
- PyObject *suggestion = NULL;
- Py_ssize_t name_size;
- const char *name_str = PyUnicode_AsUTF8AndSize(name, &name_size);
- if (name_str == NULL) {
- return NULL;
- }
-
- for (int i = 0; i < dir_size; ++i) {
- PyObject *item = PyList_GET_ITEM(dir, i);
- Py_ssize_t item_size;
- const char *item_str = PyUnicode_AsUTF8AndSize(item, &item_size);
- if (item_str == NULL) {
- return NULL;
- }
- if (PyUnicode_CompareWithASCIIString(name, item_str) == 0) {
- continue;
- }
- // No more than 1/3 of the involved characters should need changed.
- Py_ssize_t max_distance = (name_size + item_size + 3) * MOVE_COST / 6;
- // Don't take matches we've already beaten.
- max_distance = Py_MIN(max_distance, suggestion_distance - 1);
- Py_ssize_t current_distance =
- levenshtein_distance(name_str, name_size,
- item_str, item_size, max_distance);
- if (current_distance > max_distance) {
- continue;
- }
- if (!suggestion || current_distance < suggestion_distance) {
- suggestion = item;
- suggestion_distance = current_distance;
- }
- }
- Py_XINCREF(suggestion);
- return suggestion;
-}
-
-static PyObject *
-offer_suggestions_for_attribute_error(PyAttributeErrorObject *exc)
-{
- PyObject *name = exc->name; // borrowed reference
- PyObject *obj = exc->obj; // borrowed reference
-
- // Abort if we don't have an attribute name or we have an invalid one
- if (name == NULL || obj == NULL || !PyUnicode_CheckExact(name)) {
- return NULL;
- }
-
- PyObject *dir = PyObject_Dir(obj);
- if (dir == NULL) {
- return NULL;
- }
-
- PyObject *suggestions = calculate_suggestions(dir, name);
- Py_DECREF(dir);
- return suggestions;
-}
-
-
-static PyObject *
-offer_suggestions_for_name_error(PyNameErrorObject *exc)
-{
- PyObject *name = exc->name; // borrowed reference
- PyTracebackObject *traceback = (PyTracebackObject *) exc->traceback; // borrowed reference
- // Abort if we don't have a variable name or we have an invalid one
- // or if we don't have a traceback to work with
- if (name == NULL || !PyUnicode_CheckExact(name) ||
- traceback == NULL || !Py_IS_TYPE(traceback, &PyTraceBack_Type)
- ) {
- return NULL;
- }
-
- // Move to the traceback of the exception
- while (1) {
- PyTracebackObject *next = traceback->tb_next;
- if (next == NULL || !Py_IS_TYPE(next, &PyTraceBack_Type)) {
- break;
- }
- else {
- traceback = next;
- }
- }
-
- PyFrameObject *frame = traceback->tb_frame;
- assert(frame != NULL);
- PyCodeObject *code = frame->f_code;
- assert(code != NULL && code->co_varnames != NULL);
- PyObject *dir = PySequence_List(code->co_varnames);
- if (dir == NULL) {
- return NULL;
- }
-
- PyObject *suggestions = calculate_suggestions(dir, name);
- Py_DECREF(dir);
- if (suggestions != NULL) {
- return suggestions;
- }
-
- dir = PySequence_List(frame->f_globals);
- if (dir == NULL) {
- return NULL;
- }
- suggestions = calculate_suggestions(dir, name);
- Py_DECREF(dir);
- if (suggestions != NULL) {
- return suggestions;
- }
-
- dir = PySequence_List(frame->f_builtins);
- if (dir == NULL) {
- return NULL;
- }
- suggestions = calculate_suggestions(dir, name);
- Py_DECREF(dir);
-
- return suggestions;
-}
-
-// Offer suggestions for a given exception. Returns a python string object containing the
-// suggestions. This function returns NULL if no suggestion was found or if an exception happened,
-// users must call PyErr_Occurred() to disambiguate.
-PyObject *
-_Py_Offer_Suggestions(PyObject *exception)
-{
- PyObject *result = NULL;
- assert(!PyErr_Occurred());
- if (Py_IS_TYPE(exception, (PyTypeObject*)PyExc_AttributeError)) {
- result = offer_suggestions_for_attribute_error((PyAttributeErrorObject *) exception);
- } else if (Py_IS_TYPE(exception, (PyTypeObject*)PyExc_NameError)) {
- result = offer_suggestions_for_name_error((PyNameErrorObject *) exception);
- }
- return result;
-}
-
-Py_ssize_t
-_Py_UTF8_Edit_Cost(PyObject *a, PyObject *b, Py_ssize_t max_cost)
-{
- assert(PyUnicode_Check(a) && PyUnicode_Check(b));
- Py_ssize_t size_a, size_b;
- const char *utf8_a = PyUnicode_AsUTF8AndSize(a, &size_a);
- if (utf8_a == NULL) {
- return -1;
- }
- const char *utf8_b = PyUnicode_AsUTF8AndSize(b, &size_b);
- if (utf8_b == NULL) {
- return -1;
- }
- if (max_cost == -1) {
- max_cost = MOVE_COST * Py_MAX(size_a, size_b);
- }
- return levenshtein_distance(utf8_a, size_a, utf8_b, size_b, max_cost);
-}
-