make token analyzers configurable modules

Adds a mandatory section 'analyzer' to the token-analysis entries
which define, which analyser to use. Currently there is exactly
one, generic, which implements the former ICUNameProcessor.

test/python/tokenizer/token_analysis/test_generic.py

@@ -0,0 +1,104 @@
+"""
+Tests for import name normalisation and variant generation.
+"""
+from textwrap import dedent
+
+import pytest
+
+from nominatim.tokenizer.icu_rule_loader import ICURuleLoader
+
+from nominatim.errors import UsageError
+
+@pytest.fixture
+def cfgfile(def_config, tmp_path):
+    project_dir = tmp_path / 'project_dir'
+    project_dir.mkdir()
+    def_config.project_dir = project_dir
+
+    def _create_config(*variants, **kwargs):
+        content = dedent("""\
+        normalization:
+            - ":: NFD ()"
+            - "'🜳' > ' '"
+            - "[[:Nonspacing Mark:] [:Cf:]] >"
+            - ":: lower ()"
+            - "[[:Punctuation:][:Space:]]+ > ' '"
+            - ":: NFC ()"
+        transliteration:
+            - "::  Latin ()"
+            - "'🜵' > ' '"
+        """)
+        content += "token-analysis:\n  - analyzer: generic\n    variants:\n      - words:\n"
+        content += '\n'.join(("          - " + s for s in variants)) + '\n'
+        for k, v in kwargs:
+            content += "        {}: {}\n".format(k, v)
+        (project_dir / 'icu_tokenizer.yaml').write_text(content)
+
+        return def_config
+
+    return _create_config
+
+
+def get_normalized_variants(proc, name):
+    return proc.get_variants_ascii(proc.get_normalized(name))
+
+
+def test_variants_empty(cfgfile):
+    config = cfgfile('saint -> 🜵', 'street -> st')
+
+    proc = ICURuleLoader(config).make_token_analysis()
+
+    assert get_normalized_variants(proc, '🜵') == []
+    assert get_normalized_variants(proc, '🜳') == []
+    assert get_normalized_variants(proc, 'saint') == ['saint']
+
+
+VARIANT_TESTS = [
+(('~strasse,~straße -> str', '~weg => weg'), "hallo", {'hallo'}),
+(('weg => wg',), "holzweg", {'holzweg'}),
+(('weg -> wg',), "holzweg", {'holzweg'}),
+(('~weg => weg',), "holzweg", {'holz weg', 'holzweg'}),
+(('~weg -> weg',), "holzweg",  {'holz weg', 'holzweg'}),
+(('~weg => w',), "holzweg", {'holz w', 'holzw'}),
+(('~weg -> w',), "holzweg",  {'holz weg', 'holzweg', 'holz w', 'holzw'}),
+(('~weg => weg',), "Meier Weg", {'meier weg', 'meierweg'}),
+(('~weg -> weg',), "Meier Weg", {'meier weg', 'meierweg'}),
+(('~weg => w',), "Meier Weg", {'meier w', 'meierw'}),
+(('~weg -> w',), "Meier Weg", {'meier weg', 'meierweg', 'meier w', 'meierw'}),
+(('weg => wg',), "Meier Weg", {'meier wg'}),
+(('weg -> wg',), "Meier Weg", {'meier weg', 'meier wg'}),
+(('~strasse,~straße -> str', '~weg => weg'), "Bauwegstraße",
+     {'bauweg straße', 'bauweg str', 'bauwegstraße', 'bauwegstr'}),
+(('am => a', 'bach => b'), "am bach", {'a b'}),
+(('am => a', '~bach => b'), "am bach", {'a b'}),
+(('am -> a', '~bach -> b'), "am bach", {'am bach', 'a bach', 'am b', 'a b'}),
+(('am -> a', '~bach -> b'), "ambach", {'ambach', 'am bach', 'amb', 'am b'}),
+(('saint -> s,st', 'street -> st'), "Saint Johns Street",
+     {'saint johns street', 's johns street', 'st johns street',
+      'saint johns st', 's johns st', 'st johns st'}),
+(('river$ -> r',), "River Bend Road", {'river bend road'}),
+(('river$ -> r',), "Bent River", {'bent river', 'bent r'}),
+(('^north => n',), "North 2nd Street", {'n 2nd street'}),
+(('^north => n',), "Airport North", {'airport north'}),
+(('am -> a',), "am am am am am am am am", {'am am am am am am am am'}),
+(('am => a',), "am am am am am am am am", {'a a a a a a a a'})
+]
+
+@pytest.mark.parametrize("rules,name,variants", VARIANT_TESTS)
+def test_variants(cfgfile, rules, name, variants):
+    config = cfgfile(*rules)
+    proc = ICURuleLoader(config).make_token_analysis()
+
+    result = get_normalized_variants(proc, name)
+
+    assert len(result) == len(set(result))
+    assert set(get_normalized_variants(proc, name)) == variants
+
+
+def test_search_normalized(cfgfile):
+    config = cfgfile('~street => s,st', 'master => mstr')
+    proc = ICURuleLoader(config).make_token_analysis()
+
+    assert proc.get_search_normalized('Master Street') == 'master street'
+    assert proc.get_search_normalized('Earnes St') == 'earnes st'
+    assert proc.get_search_normalized('Nostreet') == 'nostreet'