2026-1-6

venv/Lib/site-packages/whoosh/lang/snowball/bases.py

@@ -0,0 +1,133 @@
+# Base classes
+
+
+class _ScandinavianStemmer(object):
+
+    """
+    This subclass encapsulates a method for defining the string region R1.
+    It is used by the Danish, Norwegian, and Swedish stemmer.
+
+    """
+
+    def _r1_scandinavian(self, word, vowels):
+        """
+        Return the region R1 that is used by the Scandinavian stemmers.
+
+        R1 is the region after the first non-vowel following a vowel,
+        or is the null region at the end of the word if there is no
+        such non-vowel. But then R1 is adjusted so that the region
+        before it contains at least three letters.
+
+        :param word: The word whose region R1 is determined.
+        :type word: str or unicode
+        :param vowels: The vowels of the respective language that are
+                       used to determine the region R1.
+        :type vowels: unicode
+        :return: the region R1 for the respective word.
+        :rtype: unicode
+        :note: This helper method is invoked by the respective stem method of
+               the subclasses DanishStemmer, NorwegianStemmer, and
+               SwedishStemmer. It is not to be invoked directly!
+
+        """
+        r1 = ""
+        for i in range(1, len(word)):
+            if word[i] not in vowels and word[i - 1] in vowels:
+                if len(word[:i + 1]) < 3 and len(word[:i + 1]) > 0:
+                    r1 = word[3:]
+                elif len(word[:i + 1]) >= 3:
+                    r1 = word[i + 1:]
+                else:
+                    return word
+                break
+
+        return r1
+
+
+class _StandardStemmer(object):
+    """
+    This subclass encapsulates two methods for defining the standard versions
+    of the string regions R1, R2, and RV.
+    """
+
+    def _r1r2_standard(self, word, vowels):
+        """
+        Return the standard interpretations of the string regions R1 and R2.
+
+        R1 is the region after the first non-vowel following a vowel,
+        or is the null region at the end of the word if there is no
+        such non-vowel.
+
+        R2 is the region after the first non-vowel following a vowel
+        in R1, or is the null region at the end of the word if there
+        is no such non-vowel.
+
+        :param word: The word whose regions R1 and R2 are determined.
+        :type word: str or unicode
+        :param vowels: The vowels of the respective language that are
+                       used to determine the regions R1 and R2.
+        :type vowels: unicode
+        :return: (r1,r2), the regions R1 and R2 for the respective word.
+        :rtype: tuple
+        :note: This helper method is invoked by the respective stem method of
+               the subclasses DutchStemmer, FinnishStemmer,
+               FrenchStemmer, GermanStemmer, ItalianStemmer,
+               PortugueseStemmer, RomanianStemmer, and SpanishStemmer.
+               It is not to be invoked directly!
+        :note: A detailed description of how to define R1 and R2
+               can be found at http://snowball.tartarus.org/texts/r1r2.html
+
+        """
+        r1 = ""
+        r2 = ""
+        for i in range(1, len(word)):
+            if word[i] not in vowels and word[i - 1] in vowels:
+                r1 = word[i + 1:]
+                break
+
+        for i in range(1, len(r1)):
+            if r1[i] not in vowels and r1[i - 1] in vowels:
+                r2 = r1[i + 1:]
+                break
+
+        return (r1, r2)
+
+    def _rv_standard(self, word, vowels):
+        """
+        Return the standard interpretation of the string region RV.
+
+        If the second letter is a consonant, RV is the region after the
+        next following vowel. If the first two letters are vowels, RV is
+        the region after the next following consonant. Otherwise, RV is
+        the region after the third letter.
+
+        :param word: The word whose region RV is determined.
+        :type word: str or unicode
+        :param vowels: The vowels of the respective language that are
+                       used to determine the region RV.
+        :type vowels: unicode
+        :return: the region RV for the respective word.
+        :rtype: unicode
+        :note: This helper method is invoked by the respective stem method of
+               the subclasses ItalianStemmer, PortugueseStemmer,
+               RomanianStemmer, and SpanishStemmer. It is not to be
+               invoked directly!
+
+        """
+        rv = ""
+        if len(word) >= 2:
+            if word[1] not in vowels:
+                for i in range(2, len(word)):
+                    if word[i] in vowels:
+                        rv = word[i + 1:]
+                        break
+
+            elif word[:2] in vowels:
+                for i in range(2, len(word)):
+                    if word[i] not in vowels:
+                        rv = word[i + 1:]
+                        break
+            else:
+                rv = word[3:]
+
+        return rv