Restrict alias detection to only "from" token.

Looking for "from" token during alias detection must NOT be triggered by columns and other constructs that may also have "from" (e.g. :effectiveFrom binding variable).

See #2508.

Author: gregturn

spring-data-jpa/src/main/java/org/springframework/data/jpa/repository/query/QueryUtils.java

@@ -138,7 +138,7 @@ public abstract class QueryUtils {
 	static {
 
 		StringBuilder builder = new StringBuilder();
-		builder.append("(?<=from)"); // from as starting delimiter
+		builder.append("(?<=[^a-zA-Z0-9]+from)"); // from as starting delimiter (with no characters prefixing it)
 		builder.append("(?:\\s)+"); // at least one space separating
 		builder.append(IDENTIFIER_GROUP); // Entity name, can be qualified (any
 		builder.append("(?:\\sas)*"); // exclude possible "as" keyword

spring-data-jpa/src/test/java/org/springframework/data/jpa/repository/query/DefaultQueryUtilsUnitTests.java

@@ -45,7 +45,7 @@ class DefaultQueryUtilsUnitTests {
 
 	private static final String QUERY = "select u from User u";
 	private static final String FQ_QUERY = "select u from org.acme.domain.User$Foo_Bar u";
-	private static final String SIMPLE_QUERY = "from User u";
+	private static final String SIMPLE_QUERY = " from User u";
 	private static final String COUNT_QUERY = "select count(u) from User u";
 
 	private static final String QUERY_WITH_AS = "select u from User as u where u.username = ?";

spring-data-jpa/src/test/java/org/springframework/data/jpa/repository/query/QueryEnhancerUnitTests.java

@@ -41,7 +41,7 @@ class QueryEnhancerUnitTests {
 
 	private static final String QUERY = "select u from User u";
 	private static final String FQ_QUERY = "select u from org.acme.domain.User$Foo_Bar u";
-	private static final String SIMPLE_QUERY = "from User u";
+	private static final String SIMPLE_QUERY = " from User u";
 	private static final String COUNT_QUERY = "select count(u) from User u";
 
 	private static final String QUERY_WITH_AS = "select u from User as u where u.username = ?";

spring-data-jpa/src/test/java/org/springframework/data/jpa/repository/query/QueryUtilsUnitTests.java

@@ -15,6 +15,7 @@
  */
 package org.springframework.data.jpa.repository.query;
 
+import static java.util.regex.Pattern.*;
 import static org.assertj.core.api.Assertions.*;
 import static org.springframework.data.jpa.repository.query.QueryUtils.*;
 
@@ -50,7 +51,7 @@ class QueryUtilsUnitTests {
 
 	private static final String QUERY = "select u from User u";
 	private static final String FQ_QUERY = "select u from org.acme.domain.User$Foo_Bar u";
-	private static final String SIMPLE_QUERY = "from User u";
+	private static final String SIMPLE_QUERY = " from User u";
 	private static final String COUNT_QUERY = "select count(u) from User u";
 
 	private static final String QUERY_WITH_AS = "select u from User as u where u.username = ?";
@@ -123,13 +124,52 @@ void detectsAliasCorrectly() {
 		assertThat(detectAlias("(select u from User u where not exists ((from User u2 where not exists (from User u3))))"))
 				.isEqualTo("u");
 		assertThat(detectAlias(
-				"from Foo f left join f.bar b with type(b) = BarChild where (f.id = (select max(f.id) from Foo f2 where type(f2) = FooChild) or 1 <> 1) and 1=1"))
+				" from Foo f left join f.bar b with type(b) = BarChild where (f.id = (select max(f.id) from Foo f2 where type(f2) = FooChild) or 1 <> 1) and 1=1"))
 						.isEqualTo("f");
 		assertThat(detectAlias(
 				"(from Foo f max(f) ((((select * from Foo f2 (from Foo f3) max(*)) (from Foo f4)) max(f5)) (f6)) (from Foo f7))"))
 						.isEqualTo("f");
 	}
 
+	@Test // GH-2508
+	void detectAliasWithCastCorrectly() {
+
+		assertThat(detectAlias(" from User u where (cast(:effective as date) is null) OR :effective >= u.createdAt"))
+				.isEqualTo("u");
+		assertThat(
+				detectAlias(" from User u where (cast(:effectiveDate as date) is null) OR :effectiveDate >= u.createdAt"))
+						.isEqualTo("u");
+		assertThat(
+				detectAlias(" from User u where (cast(:effectiveFrom as date) is null) OR :effectiveFrom >= u.createdAt"))
+						.isEqualTo("u");
+		assertThat(
+				detectAlias(" from User u where (cast(:e1f2f3ectiveFrom as date) is null) OR :effectiveFrom >= u.createdAt"))
+						.isEqualTo("u");
+	}
+
+	@Test
+	void foo() {
+
+		StringBuilder builder = new StringBuilder();
+		builder.append("(?<=[^a-zA-Z]+from)");
+
+		Pattern pattern = compile(builder.toString(), CASE_INSENSITIVE);
+
+		Matcher matcher = pattern.matcher("select * from User u where (cast(:effectiveDate as date) is null)");
+		int count = 0;
+		while (matcher.find()) {
+			count++;
+		}
+		assertThat(count).isEqualTo(1);
+
+		matcher = pattern.matcher("select * from User u where (cast(:effectiveFrom as date) is null)");
+		count = 0;
+		while (matcher.find()) {
+			count++;
+		}
+		assertThat(count).isEqualTo(1);
+	}
+
 	@Test // GH-2260
 	void testRemoveSubqueries() throws Exception {
 

spring-data-jpa/src/test/java/org/springframework/data/jpa/repository/query/StringQueryUnitTests.java

@@ -373,18 +373,18 @@ void checkProjection(String query, String expected, String description, boolean
 	@Test // DATAJPA-1235
 	void getAlias() {
 
-		checkAlias("from User u", "u", "simple query", false);
+		checkAlias(" from User u", "u", "simple query", false);
 		checkAlias("select count(u) from User u", "u", "count query", true);
 		checkAlias("select u from User as u where u.username = ?", "u", "with as", true);
 		checkAlias("SELECT FROM USER U", "U", "uppercase", false);
 		checkAlias("select u from  User u", "u", "simple query", true);
 		checkAlias("select u from  com.acme.User u", "u", "fully qualified package name", true);
 		checkAlias("select u from T05User u", "u", "interesting entity name", true);
-		checkAlias("from User ", null, "trailing space", false);
-		checkAlias("from User", null, "no trailing space", false);
-		checkAlias("from User as bs", "bs", "ignored as", false);
-		checkAlias("from User as AS", "AS", "ignored as using the second", false);
-		checkAlias("from User asas", "asas", "asas is weird but legal", false);
+		checkAlias(" from User ", null, "trailing space", false);
+		checkAlias(" from User", null, "no trailing space", false);
+		checkAlias(" from User as bs", "bs", "ignored as", false);
+		checkAlias(" from User as AS", "AS", "ignored as using the second", false);
+		checkAlias(" from User asas", "asas", "asas is weird but legal", false);
 
 		softly.assertAll();
 	}