Supporting cased match for fuzzy operator

3 files changed, 45 insertions, 34 deletions

diff --git a/vespalib/src/tests/fuzzy/fuzzy_matcher_test.cpp b/vespalib/src/tests/fuzzy/fuzzy_matcher_test.cpp
index 1395915fa5f..a0e261fb925 100644
--- a/vespalib/src/tests/fuzzy/fuzzy_matcher_test.cpp
+++ b/vespalib/src/tests/fuzzy/fuzzy_matcher_test.cpp
@@ -33,7 +33,7 @@ TEST(FuzzyMatcherTest, get_suffix_edge_cases) {
 }
 
 TEST(FuzzyMatcherTest, fuzzy_match_empty_prefix) {
-    FuzzyMatcher fuzzy = FuzzyMatcher::from_term("abc", 2, 0);
+    FuzzyMatcher fuzzy("abc", 2, 0, false);
     EXPECT_TRUE(fuzzy.isMatch("abc"));
     EXPECT_TRUE(fuzzy.isMatch("ABC"));
     EXPECT_TRUE(fuzzy.isMatch("ab1"));
@@ -41,8 +41,16 @@ TEST(FuzzyMatcherTest, fuzzy_match_empty_prefix) {
     EXPECT_FALSE(fuzzy.isMatch("123"));
 }
 
+TEST(FuzzyMatcherTest, fuzzy_match_cased) {
+    FuzzyMatcher fuzzy("abc", 2, 0, true);
+    EXPECT_TRUE(fuzzy.isMatch("abc"));
+    EXPECT_TRUE(fuzzy.isMatch("abC"));
+    EXPECT_TRUE(fuzzy.isMatch("aBC"));
+    EXPECT_FALSE(fuzzy.isMatch("ABC"));
+}
+
 TEST(FuzzyMatcherTest, fuzzy_match_with_prefix) {
-    FuzzyMatcher fuzzy = FuzzyMatcher::from_term("abcdef", 2, 2);
+    FuzzyMatcher fuzzy("abcdef", 2, 2, false);
     EXPECT_TRUE(fuzzy.isMatch("abcdef"));
     EXPECT_TRUE(fuzzy.isMatch("ABCDEF"));
     EXPECT_TRUE(fuzzy.isMatch("abcde1"));
@@ -52,12 +60,12 @@ TEST(FuzzyMatcherTest, fuzzy_match_with_prefix) {
 }
 
 TEST(FuzzyMatcherTest, get_prefix_is_empty) {
-    FuzzyMatcher fuzzy = FuzzyMatcher::from_term("whatever", 2, 0);
+    FuzzyMatcher fuzzy("whatever", 2, 0, false);
     EXPECT_EQ(fuzzy.getPrefix(), "");
 }
 
 TEST(FuzzyMatcherTest, term_is_empty) {
-    FuzzyMatcher fuzzy = FuzzyMatcher::from_term("", 2, 0);
+    FuzzyMatcher fuzzy("", 2, 0, false);
     EXPECT_TRUE(fuzzy.isMatch(""));
     EXPECT_TRUE(fuzzy.isMatch("a"));
     EXPECT_TRUE(fuzzy.isMatch("aa"));
@@ -65,7 +73,7 @@ TEST(FuzzyMatcherTest, term_is_empty) {
 }
 
 TEST(FuzzyMatcherTest, get_prefix_non_empty) {
-    FuzzyMatcher fuzzy = FuzzyMatcher::from_term("abcd", 2, 2);
+    FuzzyMatcher fuzzy("abcd", 2, 2, false);
     EXPECT_EQ(fuzzy.getPrefix(), "ab");
 }
 
diff --git a/vespalib/src/vespa/vespalib/fuzzy/fuzzy_matcher.cpp b/vespalib/src/vespa/vespalib/fuzzy/fuzzy_matcher.cpp
index 21fdb86a48d..89449944b73 100644
--- a/vespalib/src/vespa/vespalib/fuzzy/fuzzy_matcher.cpp
+++ b/vespalib/src/vespa/vespalib/fuzzy/fuzzy_matcher.cpp
@@ -6,8 +6,34 @@
 #include <vespa/vespalib/text/lowercase.h>
 #include <vespa/vespalib/text/utf8.h>
 
-vespalib::FuzzyMatcher vespalib::FuzzyMatcher::from_term(std::string_view term, uint32_t maxEditDistance, uint32_t prefixLength) {
-    return FuzzyMatcher(LowerCase::convert_to_ucs4(term), maxEditDistance, prefixLength);
+namespace {
+
+    std::vector<uint32_t> cased_convert_to_ucs4(std::string_view input) {
+        std::vector<uint32_t> result;
+        result.reserve(input.size());
+        vespalib::Utf8Reader reader(input.data());
+        while (reader.hasMore()) {
+            result.emplace_back(reader.getChar());
+        }
+        return result;
+    }
+
+} // anonymous
+
+vespalib::FuzzyMatcher::FuzzyMatcher():
+        _max_edit_distance(DefaultMaxEditDistance),
+        _prefix_size(DefaultPrefixSize),
+        _is_cased(false)
+{}
+
+vespalib::FuzzyMatcher::FuzzyMatcher(std::string_view term, uint32_t max_edit_distance, uint32_t prefix_size, bool is_cased):
+        _max_edit_distance(max_edit_distance),
+        _prefix_size(prefix_size),
+        _is_cased(is_cased)
+{
+    _folded_term_codepoints = _is_cased ? cased_convert_to_ucs4(term) : LowerCase::convert_to_ucs4(term);
+    _folded_term_codepoints_prefix = get_prefix(_folded_term_codepoints, _prefix_size);
+    _folded_term_codepoints_suffix = get_suffix(_folded_term_codepoints, _prefix_size);
 }
 
 std::span<const uint32_t> vespalib::FuzzyMatcher::get_prefix(const std::vector<uint32_t>& termCodepoints, uint32_t prefixLength) {
@@ -29,7 +55,7 @@ std::span<const uint32_t> vespalib::FuzzyMatcher::get_suffix(const std::vector<u
 }
 
 bool vespalib::FuzzyMatcher::isMatch(std::string_view target) const {
-    std::vector<uint32_t> targetCodepoints = LowerCase::convert_to_ucs4(target);
+    std::vector<uint32_t> targetCodepoints = _is_cased ? cased_convert_to_ucs4(target) : LowerCase::convert_to_ucs4(target);
 
     if (_prefix_size > 0) { // prefix comparison is meaningless if it's empty
         std::span<const uint32_t> targetPrefix = get_prefix(targetCodepoints, _prefix_size);
diff --git a/vespalib/src/vespa/vespalib/fuzzy/fuzzy_matcher.h b/vespalib/src/vespa/vespalib/fuzzy/fuzzy_matcher.h
index 12cc039706f..dcebc56babb 100644
--- a/vespalib/src/vespa/vespalib/fuzzy/fuzzy_matcher.h
+++ b/vespalib/src/vespa/vespalib/fuzzy/fuzzy_matcher.h
@@ -25,6 +25,7 @@ private:
 
     uint32_t _max_edit_distance; // max edit distance
     uint32_t _prefix_size;       // prefix of a term that is considered frozen, i.e. non-fuzzy
+    bool     _is_cased;
 
     std::vector<uint32_t> _folded_term_codepoints;
 
@@ -32,38 +33,14 @@ private:
     std::span<const uint32_t> _folded_term_codepoints_suffix;
 
 public:
-    FuzzyMatcher():
-            _max_edit_distance(DefaultMaxEditDistance),
-            _prefix_size(DefaultPrefixSize),
-            _folded_term_codepoints(),
-            _folded_term_codepoints_prefix(),
-            _folded_term_codepoints_suffix()
-    {}
+    FuzzyMatcher();
 
-    FuzzyMatcher(const std::vector<uint32_t>&& codepoints):
-            _max_edit_distance(DefaultMaxEditDistance),
-            _prefix_size(DefaultPrefixSize),
-            _folded_term_codepoints(codepoints),
-            _folded_term_codepoints_prefix(get_prefix(_folded_term_codepoints, _prefix_size)),
-            _folded_term_codepoints_suffix(get_suffix(_folded_term_codepoints, _prefix_size))
-    {}
-
-    FuzzyMatcher(const std::vector<uint32_t>&& codepoints, uint32_t max_edit_distance, uint32_t prefix_size):
-            _max_edit_distance(max_edit_distance),
-            _prefix_size(prefix_size),
-            _folded_term_codepoints(codepoints),
-            _folded_term_codepoints_prefix(get_prefix(_folded_term_codepoints, _prefix_size)),
-            _folded_term_codepoints_suffix(get_suffix(_folded_term_codepoints, _prefix_size))
-    {}
+    FuzzyMatcher(std::string_view term, uint32_t max_edit_distance, uint32_t prefix_size, bool is_cased);
 
     [[nodiscard]] bool isMatch(std::string_view target) const;
 
     [[nodiscard]] vespalib::string getPrefix() const;
 
-    ///
-
-    static FuzzyMatcher from_term(std::string_view term, uint32_t maxEditDistance, uint32_t prefixLength);
-
     static std::span<const uint32_t> get_prefix(const std::vector<uint32_t>& termCodepoints, uint32_t prefixLength);
 
     static std::span<const uint32_t> get_suffix(const std::vector<uint32_t>& termCodepoints, uint32_t prefixLength);