feat(objectionary#226): add DummyStorage

src/main/java/org/eolang/opeo/SelectiveDecompiler.java

@@ -1,13 +1,16 @@
 package org.eolang.opeo;
 
 
+import java.nio.file.Path;
 import java.util.Arrays;
 import java.util.List;
 import java.util.stream.Collectors;
 import org.eolang.opeo.ast.OpcodeName;
 import org.eolang.opeo.decompilation.Decompiler;
 import org.eolang.opeo.decompilation.handlers.RouterHandler;
 import org.eolang.opeo.jeo.JeoDecompiler;
+import org.eolang.opeo.storage.DummyStorage;
+import org.eolang.opeo.storage.FileStorage;
 import org.eolang.opeo.storage.Storage;
 import org.eolang.opeo.storage.XmirEntry;
 
@@ -34,12 +37,30 @@ public final class SelectiveDecompiler implements Decompiler {
 
     private final String[] supported;
 
-    public SelectiveDecompiler(final Storage storage) {
-        this(storage, new RouterHandler(true).supportedOpcodes());
+
+    public SelectiveDecompiler(final Path input, final Path output, final Path copy) {
+        this(input, output, copy, new RouterHandler(false).supportedOpcodes());
+    }
+
+    public SelectiveDecompiler(final Path input, final Path output) {
+        this(input, output, new RouterHandler(false).supportedOpcodes());
+    }
+
+
+    public SelectiveDecompiler(
+        final Path input, final Path output, final Path copy, String... supported
+    ) {
+        this(new FileStorage(input, output), new FileStorage(copy, copy), supported);
+    }
+
+    public SelectiveDecompiler(
+        final Path input, final Path output, String... supported
+    ) {
+        this(new FileStorage(input, output), supported);
     }
 
     public SelectiveDecompiler(final Storage storage, String... supported) {
-        this(storage, storage, supported);
+        this(storage, new DummyStorage(), supported);
     }
 
     public SelectiveDecompiler(

src/main/java/org/eolang/opeo/storage/DummyStorage.java

@@ -0,0 +1,16 @@
+package org.eolang.opeo.storage;
+
+import com.jcabi.log.Logger;
+import java.util.stream.Stream;
+
+public final class DummyStorage implements Storage {
+    @Override
+    public Stream<XmirEntry> all() {
+        return Stream.empty();
+    }
+
+    @Override
+    public void save(final XmirEntry xmir) {
+        Logger.debug(this, "Dummy storage: skip %s", xmir);
+    }
+}

src/test/java/org/eolang/opeo/decompilation/SelectiveDecompilerTest.java

@@ -31,7 +31,6 @@
 import org.cactoos.io.ResourceOf;
 import org.eolang.opeo.SelectiveDecompiler;
 import org.eolang.opeo.decompilation.handlers.RouterHandler;
-import org.eolang.opeo.storage.FileStorage;
 import org.hamcrest.MatcherAssert;
 import org.hamcrest.Matchers;
 import org.hamcrest.io.FileMatchers;
@@ -58,7 +57,7 @@ void decompiles(@TempDir final Path temp) throws Exception {
         Files.createDirectories(input);
         Files.createDirectories(output);
         Files.write(input.resolve("Bar.xmir"), known);
-        new SelectiveDecompiler(new FileStorage(input, output), this.supported).decompile();
+        new SelectiveDecompiler(input, output, this.supported).decompile();
         MatcherAssert.assertThat(
             "We expect that decompiler will decompile the input file and store the result into the output folder.",
             output.resolve("Bar.xmir").toFile(),
@@ -79,7 +78,7 @@ void decompilesNothing(@TempDir final Path temp) throws Exception {
         Files.createDirectories(input);
         Files.createDirectories(output);
         Files.write(input.resolve("Bar.xmir"), known);
-        new SelectiveDecompiler(new FileStorage(input, output)).decompile();
+        new SelectiveDecompiler(input, output).decompile();
         MatcherAssert.assertThat(
             "We expect that decompiler will copy the input file and store the result into the output folder.",
             output.resolve("Bar.xmir").toFile(),
@@ -102,7 +101,7 @@ void decompilesOnlySomeFiles(@TempDir final Path temp) throws Exception {
         Files.createDirectories(output);
         Files.write(input.resolve("Known.xmir"), known);
         Files.write(input.resolve("Unknown.xmir"), unknown);
-        new SelectiveDecompiler(new FileStorage(input, output)).decompile();
+        new SelectiveDecompiler(input, output).decompile();
         MatcherAssert.assertThat(
             "We expect that the decompiled file will be changed since the decompiler knows all instructions.",
             new BytesOf(output.resolve("Known.xmir")).asBytes(),
@@ -115,4 +114,48 @@ void decompilesOnlySomeFiles(@TempDir final Path temp) throws Exception {
         );
     }
 
+    @Test
+    void copiesDecompiledFiles(@TempDir final Path temp) throws Exception {
+        final byte[] known = new BytesOf(new ResourceOf("xmir/Known.xmir")).asBytes();
+        final Path input = temp.resolve("input");
+        final Path output = temp.resolve("output");
+        final Path copy = temp.resolve("copy");
+        Files.createDirectories(input);
+        Files.createDirectories(output);
+        Files.createDirectories(copy);
+        Files.write(input.resolve("Known.xmir"), known);
+        new SelectiveDecompiler(input, output, copy, this.supported).decompile();
+        MatcherAssert.assertThat(
+            "We expect that the decompiled file will be stored in the output folder.",
+            output.resolve("Known.xmir").toFile(),
+            FileMatchers.anExistingFile()
+        );
+        MatcherAssert.assertThat(
+            "We expect that the decompiled file will be stored in the copy folder.",
+            copy.resolve("Known.xmir").toFile(),
+            FileMatchers.anExistingFile()
+        );
+        MatcherAssert.assertThat(
+            "We expect that the decompiled file will be the same in the output and copy folders.",
+            new BytesOf(output.resolve("Known.xmir")).asBytes(),
+            Matchers.equalTo(new BytesOf(copy.resolve("Known.xmir")).asBytes())
+        );
+    }
+
+    @Test
+    void doesNotCopyDecompiledFiles(@TempDir final Path temp) throws Exception {
+        final byte[] known = new BytesOf(new ResourceOf("xmir/Known.xmir")).asBytes();
+        final Path input = temp.resolve("input");
+        final Path output = temp.resolve("output");
+        Files.createDirectories(input);
+        Files.createDirectories(output);
+        Files.write(input.resolve("Known.xmir"), known);
+        new SelectiveDecompiler(input, output, this.supported).decompile();
+        MatcherAssert.assertThat(
+            "We expect that nothing additional will be stored in the folder instead of 'input' and 'output' folders.",
+            temp.toFile().listFiles(),
+            Matchers.arrayWithSize(2)
+        );
+    }
+
 }