DATAJPA-1318 - Make the detection of default projections more robust.

We no longer detect an empty String as an alias when the entity name is followed by a space.
The comparison of the projection with the alias now ignores the case.

Original pull request: #266.

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

@@ -132,7 +132,7 @@ public abstract class QueryUtils {
 		builder.append(IDENTIFIER_GROUP); // Entity name, can be qualified (any
 		builder.append("(?:\\sas)*"); // exclude possible "as" keyword
 		builder.append("(?:\\s)+"); // at least one space separating
-		builder.append("(?!(?:where))(\\w*)"); // the actual alias
+		builder.append("(?!(?:where))(\\w+)"); // the actual alias
 
 		ALIAS_MATCH = compile(builder.toString(), CASE_INSENSITIVE);
 
@@ -544,7 +544,8 @@ public abstract class QueryUtils {
 		Assert.hasText(query, "Query must not be null or empty!");
 
 		Matcher matcher = PROJECTION_CLAUSE.matcher(query);
-		return matcher.find() ? matcher.group(1) : "";
+		String projection = matcher.find() ? matcher.group(1) : "";
+		return projection.trim();
 	}
 
 	/**

src/main/java/org/springframework/data/jpa/repository/query/StringQuery.java

@@ -152,7 +152,7 @@ class StringQuery implements DeclaredQuery {
 	 */
 	@Override
 	public boolean isDefaultProjection() {
-		return getProjection().equals(alias);
+		return getProjection().equalsIgnoreCase(alias);
 	}
 
 	/*

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

@@ -340,7 +340,12 @@ public class StringQueryUnitTests {
 		checkAlias("SELECT FROM USER U", "U", "uppercase");
 		checkAlias("select u from  User u", "u", "simple query");
 		checkAlias("select u from  com.acme.User u", "u", "fully qualified package name");
-		checkAlias("select u from T05User u", "u", "intersting entity name");
+		checkAlias("select u from T05User u", "u", "interesting entity name");
+		checkAlias("from User ", null, "trailing space");
+		checkAlias("from User", null, "no trailing space");
+		checkAlias("from User as bs", "bs", "ignored as");
+		checkAlias("from User as AS", "AS", "ignored as using the second");
+		checkAlias("from User asas", "asas", "asas is weird but legal");
 
 		softly.assertAll();
 	}
@@ -470,6 +475,43 @@ public class StringQueryUnitTests {
 		softly.assertAll();
 	}
 
+	@Test // DATAJPA-1318
+	public void isNotDefaultProjection() {
+
+		List<String> queriesWithoutDefaultProjection = Arrays.asList( //
+				"select a, b from C as c", //
+				"SELECT a, b FROM C as c", //
+				"SELECT a, b FROM C", //
+				"SELECT a, b FROM C ", //
+				"select a, b from C ", //
+				"select a, b from C");
+
+		for (String queryString : queriesWithoutDefaultProjection) {
+			softly.assertThat(new StringQuery(queryString).isDefaultProjection()) //
+					.describedAs(queryString) //
+					.isFalse();
+		}
+
+		List<String> queriesWithDefaultProjection = Arrays.asList( //
+				"select c from C as c", //
+				"SELECT c FROM C as c", //
+				"SELECT c FROM C as c ", //
+				"SELECT c  FROM C as c", //
+				"SELECT  c FROM C as c", //
+				"SELECT  c FROM C as C", //
+				"SELECT  C FROM C as c", //
+				"SELECT  C FROM C as C" //
+		);
+
+		for (String queryString : queriesWithDefaultProjection) {
+			softly.assertThat(new StringQuery(queryString).isDefaultProjection()) //
+					.describedAs(queryString) //
+					.isTrue();
+		}
+
+		softly.assertAll();
+	}
+
 	public void checkNumberOfNamedParameters(String query, int expectedSize, String label) {
 
 		DeclaredQuery declaredQuery = DeclaredQuery.of(query);