introduce property-based testing using hypothesis

.travis.yml

@@ -1,7 +1,7 @@
 env:
   global:
     - CIBW_TEST_REQUIRES=nose
-    - CIBW_TEST_COMMAND="nosetests {project}/test"
+    - CIBW_TEST_COMMAND="pip3 install -r {project}/requirements/test.txt && nosetests {project}/test"
     - TWINE_USERNAME=aflc
 matrix:
   include:
@@ -15,13 +15,15 @@ matrix:
       sudo: required
       language: generic
 
-script:
+install:
 - |
     if [ "$TRAVIS_OS_NAME" == "osx" ]; then
       sudo pip3 install cibuildwheel==0.10.1 twine
     else
       pip3 install cibuildwheel==0.10.1 twine
     fi
+
+script:
 - cibuildwheel --output-dir wheelhouse
 - |
     if [[ $TRAVIS_TAG ]]; then

README.rst

@@ -39,6 +39,15 @@ It's quite simple:
     editdistance.eval('banana', 'bahama')
     # 2L
 
+-----
+Test
+-----
+
+.. code-block:: bash
+
+    pip install -r requirements/test.txt
+    pytest test/
+
 
 ----------------
 Simple Benchmark

appveyor.yml

@@ -1,12 +1,15 @@
 environment:
   TWINE_USERNAME: aflc
+  CIBW_SKIP: cp27-*
   CIBW_TEST_REQUIRES: nose
-  CIBW_TEST_COMMAND: "nosetests {project}/test"
+  CIBW_TEST_COMMAND: "python -m pip install -r {project}\\requirements\\test.txt && nosetests {project}\\test"
 
 
+install:
+  - python -m pip install cibuildwheel==1.1.0
+
 build_script:
-  - pip install cibuildwheel==0.9.4
-  - cibuildwheel --output-dir wheelhouse
+  - python -m cibuildwheel --output-dir wheelhouse
   - ps: >-
       if ($env:APPVEYOR_REPO_TAG -eq "true") {
         python -m pip install twine

requirements/test.txt

@@ -0,0 +1,3 @@
+pytest==5.3.5
+hypothesis==5.4.2
+textdistance==4.1.5

test/test_editdistance.py

@@ -1,10 +1,88 @@
+# -*- coding: utf-8 -*-
+
+import unicodedata
 import unittest
 
+from hypothesis import event, given, strategies as st
+
+from textdistance import Levenshtein
+
+
+REFERENCE = Levenshtein().distance
+
+
+MIN_LENGTH = 0
+MAX_LENGTH = 16
+
+
 class TestEditDistance(unittest.TestCase):
-    def test_editdistance(self):
+    @given(
+        str0=st.text(
+            alphabet=st.characters(
+                min_codepoint=0,
+                max_codepoint=127),
+            min_size=MIN_LENGTH,
+            max_size=MAX_LENGTH),
+        str1=st.text(
+            alphabet=st.characters(
+                min_codepoint=0,
+                max_codepoint=127),
+            min_size=MIN_LENGTH,
+            max_size=MAX_LENGTH))
+    def test_ascii_codes(self, str0, str1):
+        norm_str0 = unicodedata.normalize('NFKC', str0)
+        norm_str1 = unicodedata.normalize('NFKC', str1)
+        event('eval("{}", "{}")'.format(norm_str0, norm_str1))
+
+        import editdistance
+        assert REFERENCE(norm_str0, norm_str1) == \
+            editdistance.eval(norm_str0, norm_str1)
+
+    @given(
+        str0=st.text(
+            alphabet=st.characters(
+                min_codepoint=12354,   # あ
+                max_codepoint=12435),  # ん
+            min_size=MIN_LENGTH,
+            max_size=MAX_LENGTH),
+        str1=st.text(
+            alphabet=st.characters(
+                min_codepoint=12354,
+                max_codepoint=12435),
+            min_size=MIN_LENGTH,
+            max_size=MAX_LENGTH))
+    def test_japanese_hiraganas(self, str0, str1):
+        norm_str0 = unicodedata.normalize('NFKC', str0)
+        norm_str1 = unicodedata.normalize('NFKC', str1)
+        event('eval("{}", "{}")'.format(norm_str0, norm_str1))
+
         import editdistance
-        self.assertEqual(1, editdistance.eval('abc', 'aec'))
-
+        assert REFERENCE(norm_str0, norm_str1) == \
+            editdistance.eval(norm_str0, norm_str1)
+
+    @given(
+        str0=st.text(
+            alphabet=st.characters(
+                min_codepoint=12450,   # ア
+                max_codepoint=12531),  # ン
+            min_size=MIN_LENGTH,
+            max_size=MAX_LENGTH),
+        str1=st.text(
+            alphabet=st.characters(
+                min_codepoint=12450,
+                max_codepoint=12531),
+            min_size=MIN_LENGTH,
+            max_size=MAX_LENGTH))
+    def test_japanese_katakanas(self, str0, str1):
+        norm_str0 = unicodedata.normalize('NFKC', str0)
+        norm_str1 = unicodedata.normalize('NFKC', str1)
+        event('eval("{}", "{}")'.format(norm_str0, norm_str1))
+
+        import editdistance
+        assert REFERENCE(norm_str0, norm_str1) == \
+            editdistance.eval(norm_str0, norm_str1)
+
 
 if __name__ == '__main__':
-    unittest.main()
+    import pytest
+    pytest.main([__file__])