Add test for HTML generation

src/main/java/org/fedoraproject/javapackages/validator/MainTmt.java

@@ -55,7 +55,7 @@ public static Main create(Path tmtTestData, Path tmtTree) {
         return result;
     }
 
-    private static final class HtmlTablePrintStream extends PrintStream {
+    static final class HtmlTablePrintStream extends PrintStream {
         public HtmlTablePrintStream(OutputStream os, TestResult result) throws IOException {
             super(os, false, StandardCharsets.UTF_8);
             var maxValue = switch (result)

src/test/java/org/fedoraproject/javapackages/validator/HtmlTablePrintStreamTest.java

@@ -0,0 +1,82 @@
+package org.fedoraproject.javapackages.validator;
+
+import java.io.ByteArrayOutputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Optional;
+import org.fedoraproject.javapackages.validator.MainTmt.HtmlTablePrintStream;
+import org.fedoraproject.javapackages.validator.spi.Decorated;
+import org.fedoraproject.javapackages.validator.spi.Decoration;
+import org.fedoraproject.javapackages.validator.spi.Decoration.Color;
+import org.fedoraproject.javapackages.validator.spi.Decoration.Modifier;
+import org.fedoraproject.javapackages.validator.spi.LogEntry;
+import org.fedoraproject.javapackages.validator.spi.LogEvent;
+import org.fedoraproject.javapackages.validator.spi.TestResult;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+class HtmlTablePrintStreamTest {
+
+    @TempDir
+    Path outDir;
+
+    @Test
+    void testHtmlGeneration() throws Exception {
+        var lorem =
+                "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do "
+                        + "eiusmod tempor incididunt ut labore et dolore magna aliqua.";
+
+        List<Optional<Color>> colors = new ArrayList<>();
+        colors.add(Optional.empty());
+        for (var color : Color.values()) {
+            colors.add(Optional.of(color));
+        }
+
+        List<Modifier[]> modas = new ArrayList<>();
+        for (int i = 0; i < 1 << Modifier.values().length; i++) {
+            List<Modifier> modifiers = new ArrayList<>();
+            for (int j = 0; j < Modifier.values().length; j++) {
+                if ((i & (1 << j)) != 0) {
+                    modifiers.add(Modifier.values()[j]);
+                }
+            }
+            var moda = modifiers.toArray(new Modifier[modifiers.size()]);
+            modas.add(moda);
+        }
+
+        List<LogEntry> entries = new ArrayList<>();
+        for (LogEvent event : LogEvent.values()) {
+            for (var moda : modas) {
+                for (var color : colors) {
+                    var entry =
+                            new LogEntry(
+                                    event,
+                                    "Text in color {0} and modifiers {1}: {2}",
+                                    Decorated.custom(color, new Decoration(color)),
+                                    Decorated.custom(Arrays.asList(moda), new Decoration(moda)),
+                                    Decorated.custom(lorem, new Decoration(color, moda)));
+                    entries.add(entry);
+                }
+            }
+        }
+
+        Path htmlDir = outDir.resolve("html");
+        Files.createDirectory(htmlDir);
+        for (String res : List.of("filter.js", "style.css")) {
+            try (var os = Files.newOutputStream(outDir.resolve(res));
+                    var is = MainTmt.class.getResourceAsStream("/tmt_html/" + res)) {
+                is.transferTo(os);
+            }
+        }
+        try (ByteArrayOutputStream bos = new ByteArrayOutputStream()) {
+            try (HtmlTablePrintStream htps = new HtmlTablePrintStream(bos, TestResult.info)) {
+                entries.forEach(htps::printRow);
+            }
+            Files.write(htmlDir.resolve("index.html"), bos.toByteArray());
+        }
+        System.err.println("Generated HTML is available at " + htmlDir);
+    }
+}