ESQL: Fix conversion of a Lucene wildcard pattern to a regexp

docs/changelog/128750.yaml

@@ -0,0 +1,7 @@
+pr: 128750
+summary: Fix conversion of a Lucene wildcard pattern to a regexp
+area: ES|QL
+type: bug
+issues:
+ - 128677
+ - 128676

muted-tests.yml

@@ -489,12 +489,6 @@ tests:
 - class: org.elasticsearch.packaging.test.DockerTests
   method: test085EnvironmentVariablesAreRespectedUnderDockerExec
   issue: https://github.com/elastic/elasticsearch/issues/128115
-- class: org.elasticsearch.xpack.esql.expression.function.scalar.string.WildcardLikeTests
-  method: testEvaluateInManyThreads {TestCase=100 random code points matches self case insensitive with keyword}
-  issue: https://github.com/elastic/elasticsearch/issues/128676
-- class: org.elasticsearch.xpack.esql.expression.function.scalar.string.WildcardLikeTests
-  method: testEvaluateInManyThreads {TestCase=100 random code points matches self case insensitive with text}
-  issue: https://github.com/elastic/elasticsearch/issues/128677
 - class: org.elasticsearch.xpack.esql.expression.function.scalar.string.RLikeTests
   method: testEvaluateInManyThreads {TestCase=100 random code points matches self case insensitive with text}
   issue: https://github.com/elastic/elasticsearch/issues/128705

x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/util/StringUtils.java

@@ -181,6 +181,7 @@ public static String wildcardToJavaPattern(String pattern, char escape) {
 
     /**
      * Translates a Lucene wildcard pattern to a Lucene RegExp one.
+     * Note: all RegExp "optional" characters are escaped too (allowing the use of the {@code RegExp.ALL} flag).
      * @param wildcard Lucene wildcard pattern
      * @return Lucene RegExp pattern
      */
@@ -209,7 +210,10 @@ public static String luceneWildcardToRegExp(String wildcard) {
                         regex.append("\\\\");
                     }
                 }
-                case '$', '(', ')', '+', '.', '[', ']', '^', '{', '|', '}' -> regex.append("\\").append(c);
+                // reserved RegExp characters
+                case '"', '$', '(', ')', '+', '.', '[', ']', '^', '{', '|', '}' -> regex.append("\\").append(c);
+                // reserved optional RegExp characters
+                case '#', '&', '<', '>' -> regex.append("\\").append(c);
                 default -> regex.append(c);
             }
         }

x-pack/plugin/esql-core/src/test/java/org/elasticsearch/xpack/esql/core/util/StringUtilsTests.java

@@ -70,7 +70,10 @@ public void testLuceneWildcardToRegExp() {
         assertThat(luceneWildcardToRegExp("foo\\*bar"), is("foo\\*bar"));
         assertThat(luceneWildcardToRegExp("foo\\?bar\\?"), is("foo\\?bar\\?"));
         assertThat(luceneWildcardToRegExp("foo\\?bar\\"), is("foo\\?bar\\\\"));
-        assertThat(luceneWildcardToRegExp("[](){}^$.|+"), is("\\[\\]\\(\\)\\{\\}\\^\\$\\.\\|\\+"));
+        // reserved characters
+        assertThat(luceneWildcardToRegExp("\"[](){}^$.|+"), is("\\\"\\[\\]\\(\\)\\{\\}\\^\\$\\.\\|\\+"));
+        // reserved "optional" characters
+        assertThat(luceneWildcardToRegExp("#&<>"), is("\\#\\&\\<\\>"));
         assertThat(luceneWildcardToRegExp("foo\\\uD83D\uDC14bar"), is("foo\uD83D\uDC14bar"));
         assertThat(luceneWildcardToRegExp("foo\uD83D\uDC14bar"), is("foo\uD83D\uDC14bar"));
     }

x-pack/plugin/esql/qa/server/src/main/java/org/elasticsearch/xpack/esql/qa/rest/RestEsqlTestCase.java

@@ -1408,7 +1408,36 @@ public void testAsyncGetWithoutContentType() throws IOException {
                 .item(matchesMap().entry("name", "integer").entry("type", "integer")),
             values
         );
+    }
 
+    public void testReplaceStringCasingWithInsensitiveWildcardMatch() throws IOException {
+        createIndex(testIndexName(), Settings.EMPTY, """
+            {
+                "properties": {
+                    "reserved": {
+                        "type": "keyword"
+                    },
+                    "optional": {
+                        "type": "keyword"
+                    }
+                }
+            }
+            """);
+        Request doc = new Request("POST", testIndexName() + "/_doc?refresh=true");
+        doc.setJsonEntity("""
+            {
+                "reserved": "_\\"_$_(_)_+_._[_]_^_{_|_}___",
+                "optional": "_#_&_<_>___"
+            }
+            """);
+        client().performRequest(doc);
+        var query = "FROM " + testIndexName() + """
+            | WHERE TO_LOWER(reserved) LIKE "_\\"_$_(_)_+_._[_]_^_{_|_}*"
+            | WHERE TO_LOWER(optional) LIKE "_#_&_<_>*"
+            | KEEP reserved, optional
+            """;
+        var answer = runEsql(requestObjectBuilder().query(query));
+        assertThat(answer.get("values"), equalTo(List.of(List.of("_\"_$_(_)_+_._[_]_^_{_|_}___", "_#_&_<_>___"))));
     }
 
     protected static Request prepareRequestWithOptions(RequestObjectBuilder requestObject, Mode mode) throws IOException {