Merge pull request #2621 from lonvia/housenumber-analyzer

[nominatim.git] / nominatim / tokenizer / token_analysis / housenumbers.py

diff --git a/nominatim/tokenizer/token_analysis/housenumbers.py b/nominatim/tokenizer/token_analysis/housenumbers.py
index 6a838e00d395e4c05f478328aa9b7558d3da84eb..96e86b28e79982825898757756cf03cff0981475 100644 (file)
--- a/nominatim/tokenizer/token_analysis/housenumbers.py
+++ b/nominatim/tokenizer/token_analysis/housenumbers.py
@@ -15,17 +15,18 @@ from nominatim.tokenizer.token_analysis.generic_mutation import MutationVariantG
 RE_NON_DIGIT = re.compile('[^0-9]')
 RE_DIGIT_ALPHA = re.compile(r'(\d)\s*([^\d\s␣])')
 RE_ALPHA_DIGIT = re.compile(r'([^\s\d␣])\s*(\d)')
+RE_NAMED_PART = re.compile(r'[a-z]{4}')
 
 ### Configuration section
 
-def configure(rules, normalization_rules):
+def configure(rules, normalization_rules): # pylint: disable=W0613
     """ All behaviour is currently hard-coded.
     """
     return None
 
 ### Analysis section
 
-def create(normalizer, transliterator, config):
+def create(normalizer, transliterator, config): # pylint: disable=W0613
     """ Create a new token analysis instance for this module.
     """
     return HousenumberTokenAnalysis(normalizer, transliterator)
@@ -48,8 +49,14 @@ class HousenumberTokenAnalysis:
             return name
 
         norm = self.trans.transliterate(self.norm.transliterate(name))
-        norm = RE_DIGIT_ALPHA.sub(r'\1␣\2', norm)
-        norm = RE_ALPHA_DIGIT.sub(r'\1␣\2', norm)
+        # If there is a significant non-numeric part, use as is.
+        if RE_NAMED_PART.search(norm) is None:
+            # Otherwise add optional spaces between digits and letters.
+            (norm_opt, cnt1) = RE_DIGIT_ALPHA.subn(r'\1␣\2', norm)
+            (norm_opt, cnt2) = RE_ALPHA_DIGIT.subn(r'\1␣\2', norm_opt)
+            # Avoid creating too many variants per number.
+            if cnt1 + cnt2 <= 4:
+                return norm_opt
 
         return norm