Index: /applications/editors/josm/plugins/pmtiles/org.openstreetmap.josm.plugins.pmtiles.iml
===================================================================
--- /applications/editors/josm/plugins/pmtiles/org.openstreetmap.josm.plugins.pmtiles.iml	(revision 36161)
+++ /applications/editors/josm/plugins/pmtiles/org.openstreetmap.josm.plugins.pmtiles.iml	(revision 36162)
@@ -14,6 +14,6 @@
     <orderEntry type="jdk" jdkName="temurin-17" jdkType="JavaSDK" />
     <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="module" module-name="org.openstreetmap.josm.plugins.commons" />
     <orderEntry type="module" module-name="org.openstreetmap.josm" />
-    <orderEntry type="module" module-name="org.openstreetmap.josm.plugins.commons" />
   </component>
   <component name="SonarLintModuleSettings">
Index: /applications/editors/josm/plugins/pmtiles/src/test/java/unit/org/openstreetmap/josm/plugins/pmtiles/PMTestUtils.java
===================================================================
--- /applications/editors/josm/plugins/pmtiles/src/test/java/unit/org/openstreetmap/josm/plugins/pmtiles/PMTestUtils.java	(revision 36162)
+++ /applications/editors/josm/plugins/pmtiles/src/test/java/unit/org/openstreetmap/josm/plugins/pmtiles/PMTestUtils.java	(revision 36162)
@@ -0,0 +1,23 @@
+// License: GPL. For details, see LICENSE file.
+package org.openstreetmap.josm.plugins.pmtiles;
+
+import java.io.File;
+import java.net.URI;
+
+/**
+ * Utils for testing
+ */
+public final class PMTestUtils {
+    private PMTestUtils() { /* Hide constructor */ }
+    /** A sample vector tileset */
+
+    public static final URI ODBL_VECTOR_FIRENZE = new File("protomaps(vector)ODbL_firenze.pmtiles").exists() ?
+            new File("protomaps(vector)ODbL_firenze.pmtiles").toURI() :
+            URI.create("https://github.com/protomaps/PMTiles/raw/main/spec/v3/protomaps(vector)ODbL_firenze.pmtiles");
+
+    /** A sample raster tileset */
+    public static final URI ODBL_RASTER_STAMEN = new File("stamen_toner(raster)CC-BY%2BODbL_z3.pmtiles").exists() ?
+            new File("stamen_toner(raster)CC-BY%2BODbL_z3.pmtiles").toURI() :
+            URI.create("https://github.com/protomaps/PMTiles/raw/main/spec/v3/stamen_toner(raster)CC-BY%2BODbL_z3.pmtiles");
+
+}
Index: /applications/editors/josm/plugins/pmtiles/src/test/java/unit/org/openstreetmap/josm/plugins/pmtiles/gui/layers/PMTilesImageLayerTest.java
===================================================================
--- /applications/editors/josm/plugins/pmtiles/src/test/java/unit/org/openstreetmap/josm/plugins/pmtiles/gui/layers/PMTilesImageLayerTest.java	(revision 36162)
+++ /applications/editors/josm/plugins/pmtiles/src/test/java/unit/org/openstreetmap/josm/plugins/pmtiles/gui/layers/PMTilesImageLayerTest.java	(revision 36162)
@@ -0,0 +1,14 @@
+// License: GPL. For details, see LICENSE file.
+package org.openstreetmap.josm.plugins.pmtiles.gui.layers;
+
+import org.openstreetmap.josm.plugins.pmtiles.data.imagery.PMTilesImageryInfo;
+
+/**
+ * Test class for {@link PMTilesImageLayer}
+ */
+class PMTilesImageLayerTest implements PMTilesLayerTest {
+    @Override
+    public PMTilesImageLayer getLayer(PMTilesImageryInfo info) {
+        return new PMTilesImageLayer(info);
+    }
+}
Index: /applications/editors/josm/plugins/pmtiles/src/test/java/unit/org/openstreetmap/josm/plugins/pmtiles/gui/layers/PMTilesLayerTest.java
===================================================================
--- /applications/editors/josm/plugins/pmtiles/src/test/java/unit/org/openstreetmap/josm/plugins/pmtiles/gui/layers/PMTilesLayerTest.java	(revision 36162)
+++ /applications/editors/josm/plugins/pmtiles/src/test/java/unit/org/openstreetmap/josm/plugins/pmtiles/gui/layers/PMTilesLayerTest.java	(revision 36162)
@@ -0,0 +1,35 @@
+// License: GPL. For details, see LICENSE file.
+package org.openstreetmap.josm.plugins.pmtiles.gui.layers;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.openstreetmap.josm.plugins.pmtiles.PMTestUtils.ODBL_RASTER_STAMEN;
+import static org.openstreetmap.josm.plugins.pmtiles.PMTestUtils.ODBL_VECTOR_FIRENZE;
+
+import java.io.IOException;
+
+import org.junit.jupiter.api.Test;
+import org.openstreetmap.josm.plugins.pmtiles.data.imagery.PMTilesImageryInfo;
+import org.openstreetmap.josm.plugins.pmtiles.lib.PMTiles;
+import org.openstreetmap.josm.tools.TextUtils;
+import org.openstreetmap.josm.tools.Utils;
+
+/**
+ * Test class for {@link PMTilesLayer}
+ */
+interface PMTilesLayerTest {
+    PMTilesLayer getLayer(PMTilesImageryInfo info);
+
+    @Test
+    default void testSource() throws IOException {
+        final var layerRaster = getLayer(new PMTilesImageryInfo(PMTiles.readHeader(ODBL_RASTER_STAMEN)));
+        final var layerVector = getLayer(new PMTilesImageryInfo(PMTiles.readHeader(ODBL_VECTOR_FIRENZE)));
+        if (Utils.isLocalUrl(ODBL_RASTER_STAMEN.toString())) {
+            assertEquals(ODBL_RASTER_STAMEN.toString().replace(System.getProperty("user.name"), "<user.name>"),
+                    layerRaster.getChangesetSourceTag());
+        } else {
+            assertEquals(TextUtils.stripUrl(ODBL_RASTER_STAMEN.toString()), layerRaster.getChangesetSourceTag());
+        }
+        assertEquals("Protomaps © OpenStreetMap - protomaps 2023-01-18T07:49:39Z", layerVector.getChangesetSourceTag());
+    }
+
+}
Index: /applications/editors/josm/plugins/pmtiles/src/test/java/unit/org/openstreetmap/josm/plugins/pmtiles/gui/layers/PMTilesMVTLayerTest.java
===================================================================
--- /applications/editors/josm/plugins/pmtiles/src/test/java/unit/org/openstreetmap/josm/plugins/pmtiles/gui/layers/PMTilesMVTLayerTest.java	(revision 36162)
+++ /applications/editors/josm/plugins/pmtiles/src/test/java/unit/org/openstreetmap/josm/plugins/pmtiles/gui/layers/PMTilesMVTLayerTest.java	(revision 36162)
@@ -0,0 +1,14 @@
+// License: GPL. For details, see LICENSE file.
+package org.openstreetmap.josm.plugins.pmtiles.gui.layers;
+
+import org.openstreetmap.josm.plugins.pmtiles.data.imagery.PMTilesImageryInfo;
+
+/**
+ * Test class for {@link PMTilesMVTLayer}
+ */
+class PMTilesMVTLayerTest implements PMTilesLayerTest {
+    @Override
+    public PMTilesMVTLayer getLayer(PMTilesImageryInfo info) {
+        return new PMTilesMVTLayer(info);
+    }
+}
Index: /applications/editors/josm/plugins/pmtiles/src/test/java/unit/org/openstreetmap/josm/plugins/pmtiles/lib/PMTilesTest.java
===================================================================
--- /applications/editors/josm/plugins/pmtiles/src/test/java/unit/org/openstreetmap/josm/plugins/pmtiles/lib/PMTilesTest.java	(revision 36162)
+++ /applications/editors/josm/plugins/pmtiles/src/test/java/unit/org/openstreetmap/josm/plugins/pmtiles/lib/PMTilesTest.java	(revision 36162)
@@ -0,0 +1,113 @@
+// License: GPL. For details, see LICENSE file.
+package org.openstreetmap.josm.plugins.pmtiles.lib;
+
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertSame;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.openstreetmap.josm.plugins.pmtiles.PMTestUtils.ODBL_RASTER_STAMEN;
+import static org.openstreetmap.josm.plugins.pmtiles.PMTestUtils.ODBL_VECTOR_FIRENZE;
+
+import java.io.IOException;
+
+import org.junit.jupiter.api.Test;
+
+/**
+ * Test class for {@link PMTiles}
+ */
+class PMTilesTest {
+    @Test
+    void testHeader() {
+        final var header = assertDoesNotThrow(() -> PMTiles.readHeader(ODBL_VECTOR_FIRENZE));
+        assertSame(ODBL_VECTOR_FIRENZE, header.location());
+        assertEquals(InternalCompression.GZIP, header.internalCompression());
+        assertTrue(header.clustered());
+        assertEquals(TileType.MVT, header.tileType());
+        assertEquals(108, header.tileEntries());
+        assertEquals(108, header.addressedTiles());
+    }
+
+    @Test
+    void testMetadata() {
+        final var header = assertDoesNotThrow(() -> PMTiles.readHeader(ODBL_VECTOR_FIRENZE));
+        final var metadata = assertDoesNotThrow(() -> PMTiles.readMetadata(header));
+        assertNotNull(metadata);
+        assertEquals(4, metadata.size());
+        assertEquals("baselayer", metadata.getString("type"));
+        assertEquals("protomaps 2023-01-18T07:49:39Z", metadata.getString("name"));
+    }
+
+    @Test
+    void testRootDirectory() {
+        final var header = assertDoesNotThrow(() -> PMTiles.readHeader(ODBL_VECTOR_FIRENZE));
+        final var root = assertDoesNotThrow(() -> PMTiles.readRootDirectory(header));
+        assertNotNull(root);
+        assertEquals(header.tileEntries(), root.entries().length);
+        assertEquals(new DirectoryEntry(0, 0, 588, 1), root.entries()[0]);
+        assertEquals(new DirectoryEntry(317221111, 994639, 17276, 1), root.entries()[47]);
+        // Any issue with delta encoding will probably show up here
+        assertEquals(new DirectoryEntry(317301844, 3927477, 31394, 1), root.entries()[107]);
+    }
+
+    @Test
+    void testHilbertConversion() {
+        assertEquals(0, PMTiles.convertToHilbert(0, 0, 0));
+        assertEquals(1, PMTiles.convertToHilbert(1, 0, 0));
+        assertEquals(2, PMTiles.convertToHilbert(1, 0, 1));
+        assertEquals(3, PMTiles.convertToHilbert(1, 1, 1));
+        assertEquals(4, PMTiles.convertToHilbert(1, 1, 0));
+        assertEquals(5, PMTiles.convertToHilbert(2, 0, 0));
+        // This is from https://protomaps.com/blog/pmtiles-v3-hilbert-tile-ids .
+        assertEquals(36052, PMTiles.convertToHilbert(new TileXYZ(8, 40, 87)));
+    }
+
+    @Test
+    void testTileConversion() {
+        assertEquals(new TileXYZ(0, 0, 0), PMTiles.convertToXYZ(0));
+        assertEquals(new TileXYZ(1, 0, 0), PMTiles.convertToXYZ(1));
+        assertEquals(new TileXYZ(1, 0, 1), PMTiles.convertToXYZ(2));
+        assertEquals(new TileXYZ(1, 1, 1), PMTiles.convertToXYZ(3));
+        assertEquals(new TileXYZ(1, 1, 0), PMTiles.convertToXYZ(4));
+        assertEquals(new TileXYZ(2, 0, 0), PMTiles.convertToXYZ(5));
+        assertEquals(new TileXYZ(8, 40, 87), PMTiles.convertToXYZ(36052));
+    }
+
+    @Test
+    void testTileReading223() throws IOException {
+        final var header = assertDoesNotThrow(() -> PMTiles.readHeader(ODBL_RASTER_STAMEN));
+        final var root = assertDoesNotThrow(() -> PMTiles.readRootDirectory(header));
+        final var data = PMTiles.readData(header, PMTiles.convertToHilbert(2, 2, 3), new DirectoryCache(root));
+        assertEquals(new DirectoryEntry(14, 169957, 4503, 1), root.entries()[14]);
+        assertEquals(4503, data.length);
+        assertEquals((byte) 0x89, data[0]);
+        assertEquals((byte) 0x50, data[1]);
+        assertEquals((byte) 0x4e, data[2]);
+        assertEquals((byte) 0x47, data[3]);
+        assertEquals((byte) 0x0d, data[4]);
+        assertEquals((byte) 0x44, data[4498]);
+        assertEquals((byte) 0xae, data[4499]);
+        assertEquals((byte) 0x42, data[4500]);
+        assertEquals((byte) 0x60, data[4501]);
+        assertEquals((byte) 0x82, data[4502]);
+    }
+
+    @Test
+    void testTileReading352() throws IOException {
+        final var header = assertDoesNotThrow(() -> PMTiles.readHeader(ODBL_RASTER_STAMEN));
+        final var root = assertDoesNotThrow(() -> PMTiles.readRootDirectory(header));
+        final var data = PMTiles.readData(header, PMTiles.convertToHilbert(3, 5, 2), new DirectoryCache(root));
+        assertEquals(new DirectoryEntry(76, 662416, 9344, 1), root.entries()[75]);
+        assertEquals(9344, data.length);
+        assertEquals((byte) 0x89, data[0]);
+        assertEquals((byte) 0x50, data[1]);
+        assertEquals((byte) 0x4e, data[2]);
+        assertEquals((byte) 0x47, data[3]);
+        assertEquals((byte) 0x0d, data[4]);
+        assertEquals((byte) 0x44, data[9339]);
+        assertEquals((byte) 0xae, data[9340]);
+        assertEquals((byte) 0x42, data[9341]);
+        assertEquals((byte) 0x60, data[9342]);
+        assertEquals((byte) 0x82, data[9343]);
+    }
+}