(index-query) Add some tests for the QueryFilter code

code/features-index/index-query/src/main/java/nu/marginalia/index/query/filter/QueryFilterLetThrough.java

@@ -1,25 +1,24 @@
 package nu.marginalia.index.query.filter;
 
+import nu.marginalia.array.buffer.LongQueryBuffer;
+
 public class QueryFilterLetThrough implements QueryFilterStepIf {
-    static final QueryFilterStepIf instance = new QueryFilterLetThrough();
 
     @Override
     public boolean test(long value) {
         return true;
     }
 
+    @Override
+    public void apply(LongQueryBuffer buffer) {
+        buffer.retainAll();
+        buffer.finalizeFiltering();
+    }
+
     public double cost() {
         return 0.;
     }
 
-    public int retainDestructive(long[] items, int max) {
-        return 0;
-    }
-
-    public int retainReorder(long[] items, int start, int max) {
-        return 0;
-    }
-
     public String describe() {
         return "[PassThrough]";
     }

code/features-index/index-query/src/main/java/nu/marginalia/index/query/filter/QueryFilterStepIf.java

@@ -36,13 +36,5 @@ public interface QueryFilterStepIf extends Comparable<QueryFilterStepIf> {
         buffer.finalizeFiltering();
     }
 
-    static QueryFilterStepIf noPass() {
-        return QueryFilterNoPass.instance;
-    }
-    static QueryFilterStepIf anyOf(List<? extends QueryFilterStepIf> steps) {
-        return new QueryFilterAnyOf(steps);
-    }
-
-
 }
 

code/features-index/index-query/src/test/java/nu/marginalia/index/query/filter/QueryFilterStepIfTest.java

@@ -0,0 +1,67 @@
+package nu.marginalia.index.query.filter;
+
+import nu.marginalia.array.buffer.LongQueryBuffer;
+import org.junit.jupiter.api.Test;
+
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class QueryFilterStepIfTest {
+
+    private LongQueryBuffer createBuffer(long... data) {
+        return new LongQueryBuffer(data, data.length);
+    }
+
+    @Test
+    public void testPassThrough() {
+        var buffer = createBuffer(1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+        var filter = new QueryFilterLetThrough();
+        filter.apply(buffer);
+        assertArrayEquals(new long[]{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, buffer.copyData());
+    }
+
+    @Test
+    public void testNoPass() {
+        var buffer = createBuffer(1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+        var filter = new QueryFilterNoPass();
+        filter.apply(buffer);
+        assertArrayEquals(new long[]{}, buffer.copyData());
+    }
+
+    @Test
+    public void testIncludePredicate() {
+        var buffer = createBuffer(1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+        var filter = new QueryFilterStepFromPredicate(value -> value % 2 == 0);
+        filter.apply(buffer);
+        assertArrayEquals(new long[]{2, 4, 6, 8, 10}, buffer.copyData());
+    }
+
+    @Test
+    public void testExcludePredicate() {
+        var buffer = createBuffer(1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+        var filter = new QueryFilterStepExcludeFromPredicate(value -> value % 2 == 1);
+        filter.apply(buffer);
+        assertArrayEquals(new long[]{2, 4, 6, 8, 10}, buffer.copyData());
+    }
+
+    @Test
+    public void testSuccessiveApplication() {
+        var buffer = createBuffer(1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+        var filter1 = new QueryFilterStepFromPredicate(value -> value % 2 == 0);
+        var filter2 = new QueryFilterStepExcludeFromPredicate(value -> value <= 6);
+        filter1.apply(buffer);
+        filter2.apply(buffer);
+        assertArrayEquals(new long[]{8, 10}, buffer.copyData());
+    }
+
+    @Test
+    public void testCombinedApplication() {
+        var buffer = createBuffer(1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+        var filter1 = new QueryFilterStepFromPredicate(value -> value % 3 == 0);
+        var filter2 = new QueryFilterStepFromPredicate(value -> value % 5 == 0);
+        var filter = new QueryFilterAnyOf(List.of(filter1, filter2));
+        filter.apply(buffer);
+        assertArrayEquals(new long[]{3, 5, 6, 9, 10}, buffer.copyData());
+    }
+}

code/libraries/array/src/main/java/nu/marginalia/array/buffer/LongQueryBuffer.java

@@ -89,6 +89,15 @@ public class LongQueryBuffer {
         return ++read < end;
     }
 
+    /** Retains all values in the buffer, and updates
+     * the read and write pointer to the end pointer,
+     * as though all values were retained.
+     */
+    public void retainAll() {
+        write = end;
+        read = end;
+    }
+
     public boolean hasMore() {
         return read < end;
     }
@@ -147,4 +156,5 @@ public class LongQueryBuffer {
             ",data = [" + Arrays.toString(Arrays.copyOf(data, end)) + "]]";
     }
 
+
 }