DATAJPA-473 - Fixed bug in binding detection in String queries.

Query parameter binding replacements were undone if a simple binding was contained in the query. Fixed that and also make sure we don't create superfluous multiple bindings for the same variable and binding type.

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

@@ -219,7 +219,6 @@ class StringQuery {
 
 						bindings.add(parameterIndex != null ? new ParameterBinding(parameterIndex) : new ParameterBinding(
 								parameterName));
-						result = query;
 				}
 			}
 
@@ -234,7 +233,9 @@ class StringQuery {
 				}
 			}
 
-			bindings.add(binding);
+			if (!bindings.contains(binding)) {
+				bindings.add(binding);
+			}
 		}
 
 		/**

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

@@ -194,6 +194,24 @@ public class StringQueryUnitTests {
 		assertPositionalBinding(ParameterBinding.class, 1, bindings.get(0));
 	}
 
+	/**
+	 * @see DATAJPA-473
+	 */
+	@Test
+	public void removesLikeBindingsFromQueryIfQueryContainsSimpleBinding() {
+
+		StringQuery query = new StringQuery("SELECT a FROM Article a WHERE a.overview LIKE %:escapedWord% ESCAPE '~'"
+				+ " OR a.content LIKE %:escapedWord% ESCAPE '~' OR a.title = :word ORDER BY a.articleId DESC");
+
+		List<ParameterBinding> bindings = query.getParameterBindings();
+
+		assertThat(bindings, hasSize(2));
+		assertNamedBinding(LikeParameterBinding.class, "escapedWord", bindings.get(0));
+		assertNamedBinding(ParameterBinding.class, "word", bindings.get(1));
+		assertThat(query.getQueryString(), is("SELECT a FROM Article a WHERE a.overview LIKE :escapedWord ESCAPE '~'"
+				+ " OR a.content LIKE :escapedWord ESCAPE '~' OR a.title = :word ORDER BY a.articleId DESC"));
+	}
+
 	private void assertPositionalBinding(Class<? extends ParameterBinding> bindingType, Integer position,
 			ParameterBinding expectedBinding) {