Add levenshtein from polyleven (#11418)

Add a simple levenshtein distance function using the implementation from
the polyleven library as `spacy.matcher.levenshtein`.

.gitignore

@@ -24,6 +24,7 @@ quickstart-training-generator.js
 cythonize.json
 spacy/*.html
 *.cpp
+*.c
 *.so
 
 # Vim / VSCode / editors

licenses/3rd_party_licenses.txt

@@ -127,3 +127,34 @@ distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
+
+
+polyleven
+---------
+
+* Files: spacy/matcher/polyleven.c
+
+MIT License
+
+Copyright (c) 2021 Fujimoto Seiji <[email protected]>
+Copyright (c) 2021 Max Bachmann <[email protected]>
+Copyright (c) 2022 Nick Mazuk
+Copyright (c) 2022 Michael Weiss <[email protected]>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

setup.py

@@ -205,6 +205,17 @@ def setup_package():
         get_python_inc(plat_specific=True),
     ]
     ext_modules = []
+    ext_modules.append(
+        Extension(
+            "spacy.matcher.levenshtein",
+            [
+                "spacy/matcher/levenshtein.pyx",
+                "spacy/matcher/polyleven.c",
+            ],
+            language="c",
+            include_dirs=include_dirs,
+        )
+    )
     for name in MOD_NAMES:
         mod_path = name.replace(".", "/") + ".pyx"
         ext = Extension(

spacy/matcher/__init__.py

@@ -1,5 +1,6 @@
 from .matcher import Matcher
 from .phrasematcher import PhraseMatcher
 from .dependencymatcher import DependencyMatcher
+from .levenshtein import levenshtein
 
-__all__ = ["Matcher", "PhraseMatcher", "DependencyMatcher"]
+__all__ = ["Matcher", "PhraseMatcher", "DependencyMatcher", "levenshtein"]

spacy/matcher/levenshtein.pyx

@@ -0,0 +1,15 @@
+# cython: profile=True, binding=True, infer_types=True
+from cpython.object cimport PyObject
+from libc.stdint cimport int64_t
+
+from typing import Optional
+
+
+cdef extern from "polyleven.c":
+    int64_t polyleven(PyObject *o1, PyObject *o2, int64_t k)
+
+
+cpdef int64_t levenshtein(a: str, b: str, k: Optional[int] = None):
+    if k is None:
+        k = -1
+    return polyleven(<PyObject*>a, <PyObject*>b, k)