Upstream Merge

worldedit-core/src/main/java/com/sk89q/worldedit/util/PropertiesConfiguration.java

@@ -127,9 +127,8 @@ public class PropertiesConfiguration extends LocalConfiguration {
         LocalSession.MAX_HISTORY_SIZE = Math.max(15, getInt("history-size", 15));
 
         String snapshotsDir = getString("snapshots-dir", "");
-        if (!snapshotsDir.isEmpty()) {
-            snapshotRepo = new SnapshotRepository(snapshotsDir);
-        }
+        boolean experimentalSnapshots = getBool("snapshots-experimental", false);
+        initializeSnapshotConfiguration(snapshotsDir, experimentalSnapshots);
 
         path.getParentFile().mkdirs();
         try (OutputStream output = new FileOutputStream(path)) {

worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/LocatedBlockList.java

@@ -19,8 +19,6 @@
 
 package com.sk89q.worldedit.util.collection;
 
-import com.google.common.collect.Iterators;
-import com.sk89q.worldedit.WorldEdit;
 import com.google.common.collect.Iterators;
 import com.sk89q.worldedit.WorldEdit;
 import com.sk89q.worldedit.math.BlockVector3;

worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/MoreStreams.java

@@ -0,0 +1,83 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.util.collection;
+
+import com.google.common.collect.AbstractIterator;
+
+import java.util.Iterator;
+import java.util.Spliterator;
+import java.util.Spliterators;
+import java.util.function.Predicate;
+import java.util.stream.Stream;
+import java.util.stream.StreamSupport;
+
+import static java.util.Objects.requireNonNull;
+
+/**
+ * Additionally stream facilities.
+ */
+public class MoreStreams {
+
+    /**
+     * Emit elements from {@code stream} until {@code predicate} returns {@code false}.
+     */
+    public static <T> Stream<T> takeWhile(Stream<T> stream, Predicate<T> predicate) {
+        return takeUntil(stream, predicate.negate());
+    }
+
+    /**
+     * Emit elements from {@code stream} until {@code predicate} returns {@code true}.
+     */
+    public static <T> Stream<T> takeUntil(Stream<T> stream, Predicate<T> predicate) {
+        Spliterator<T> spliterator = stream.spliterator();
+        Iterator<T> iter = new AbstractIterator<T>() {
+
+            private Iterator<T> source = Spliterators.iterator(spliterator);
+
+            @Override
+            protected T computeNext() {
+                Iterator<T> src = requireNonNull(source);
+                if (!src.hasNext()) {
+                    return done();
+                }
+                T next = src.next();
+                if (predicate.test(next)) {
+                    return done();
+                }
+                return next;
+            }
+
+            private T done() {
+                // allow GC of source
+                source = null;
+                return endOfData();
+            }
+        };
+        int chars = spliterator.characteristics();
+        // Not SIZED, Not SUBSIZED
+        chars &= ~(Spliterator.SIZED | Spliterator.SUBSIZED);
+        return StreamSupport.stream(Spliterators.spliterator(
+            iter, spliterator.estimateSize(), chars
+        ), stream.isParallel()).onClose(stream::close);
+    }
+
+    private MoreStreams() {
+    }
+}

worldedit-core/src/main/java/com/sk89q/worldedit/util/concurrency/LazyReference.java

@@ -71,4 +71,5 @@ public class LazyReference<T> {
             refInfo.lock.unlock();
         }
     }
+
 }

worldedit-core/src/main/java/com/sk89q/worldedit/util/eventbus/EventBus.java

@@ -20,8 +20,6 @@
 package com.sk89q.worldedit.util.eventbus;
 
 import com.google.common.collect.HashMultimap;
-
-import static com.google.common.base.Preconditions.checkNotNull;
 import com.google.common.collect.Multimap;
 import com.google.common.collect.SetMultimap;
 import org.slf4j.Logger;
@@ -37,6 +35,8 @@ import java.util.Set;
 import java.util.concurrent.locks.ReadWriteLock;
 import java.util.concurrent.locks.ReentrantReadWriteLock;
 
+import static com.google.common.base.Preconditions.checkNotNull;
+
 /**
  * Dispatches events to listeners, and provides ways for listeners to register
  * themselves.

worldedit-core/src/main/java/com/sk89q/worldedit/util/formatting/component/TextUtils.java

@@ -47,6 +47,7 @@ public class TextUtils {
         }
         return builder.build();
     }
+
     /**
      * Gets a Java Locale object by the Minecraft locale tag.
      *

worldedit-core/src/main/java/com/sk89q/worldedit/util/function/IORunnable.java

@@ -0,0 +1,32 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.util.function;
+
+import java.io.IOException;
+
+/**
+ * I/O runnable type.
+ */
+@FunctionalInterface
+public interface IORunnable {
+
+    void run() throws IOException;
+
+}

worldedit-core/src/main/java/com/sk89q/worldedit/util/io/ResourceLoader.java

@@ -51,4 +51,4 @@ public class ResourceLoader {
         }
         return url;
     }
-}
+}

worldedit-core/src/main/java/com/sk89q/worldedit/util/io/file/ArchiveNioSupport.java

@@ -0,0 +1,40 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.util.io.file;
+
+import java.io.IOException;
+import java.nio.file.FileSystem;
+import java.nio.file.Path;
+import java.util.Optional;
+
+/**
+ * Something that can provide access to an archive file as a file system.
+ */
+public interface ArchiveNioSupport {
+
+    /**
+     * Try to open the given archive as a file system.
+     *
+     * @param archive the archive to open
+     * @return the path for the root of the archive, if available
+     */
+    Optional<Path> tryOpenAsDir(Path archive) throws IOException;
+
+}

worldedit-core/src/main/java/com/sk89q/worldedit/util/io/file/ArchiveNioSupports.java

@@ -0,0 +1,99 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.util.io.file;
+
+import com.google.common.collect.ImmutableList;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.List;
+import java.util.Optional;
+import java.util.ServiceLoader;
+import java.util.stream.Stream;
+
+public class ArchiveNioSupports {
+
+    private static final List<ArchiveNioSupport> SUPPORTS;
+
+    static {
+        ImmutableList.Builder<ArchiveNioSupport> builder = ImmutableList.builder();
+        try {
+            builder.add(TrueVfsArchiveNioSupport.getInstance());
+        } catch (NoClassDefFoundError ignore) {
+            // No TrueVFS available. That's OK.
+        }
+        SUPPORTS = builder.add(ZipArchiveNioSupport.getInstance())
+            .addAll(ServiceLoader.load(ArchiveNioSupport.class))
+            .build();
+    }
+
+    public static Optional<Path> tryOpenAsDir(Path archive) throws IOException {
+        for (ArchiveNioSupport support : SUPPORTS) {
+            Optional<Path> fs = support.tryOpenAsDir(archive);
+            if (fs.isPresent()) {
+                return fs;
+            }
+        }
+        return Optional.empty();
+    }
+
+    private static final ArchiveNioSupport COMBINED = ArchiveNioSupports::tryOpenAsDir;
+
+    /**
+     * Get an {@link ArchiveNioSupport} that combines all known instances.
+     * @return a combined {@link ArchiveNioSupport} instance
+     */
+    public static ArchiveNioSupport combined() {
+        return COMBINED;
+    }
+
+    /**
+     * If root contains a folder with the same name as {@code name}, and no regular files,
+     * returns the path to that folder. Otherwise, return the root path.
+     *
+     * <p>
+     * This method is used to provide equal outputs for archives that do and do not contain
+     * their name as part of their root folder.
+     * </p>
+     *
+     * @param root the root path
+     * @param name the name that might exist inside root
+     * @return the corrected path
+     */
+    public static Path skipRootSameName(Path root, String name) throws IOException {
+        Path innerDir = root.resolve(name);
+        if (Files.isDirectory(innerDir)) {
+            try (Stream<Path> files = Files.list(root)) {
+                // The reason we check this, is that macOS creates a __MACOSX directory inside
+                // its zip files. We want to allow this to pass if that exists, or a similar
+                // mechanism, but fail if there are regular files, since that indicates that
+                // it may not be the right thing to do.
+                if (files.allMatch(Files::isDirectory)) {
+                    return innerDir;
+                }
+            }
+        }
+        return root;
+    }
+
+    private ArchiveNioSupports() {
+    }
+}

worldedit-core/src/main/java/com/sk89q/worldedit/util/io/file/MorePaths.java

@@ -0,0 +1,68 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.util.io.file;
+
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.Streams;
+
+import java.nio.file.Path;
+import java.util.ArrayDeque;
+import java.util.Arrays;
+import java.util.Deque;
+import java.util.Spliterator;
+import java.util.stream.IntStream;
+import java.util.stream.Stream;
+
+public class MorePaths {
+
+    /**
+     * Starting with the first path element, add elements until reaching this path.
+     */
+    public static Stream<Path> iterPaths(Path path) {
+        Deque<Path> parents = new ArrayDeque<>(path.getNameCount());
+        // Push parents to the front of the stack, so the "root" is at the front
+        Path next = path;
+        while (next != null) {
+            parents.addFirst(next);
+            next = next.getParent();
+        }
+        // now just iterate straight over them
+        return ImmutableList.copyOf(parents).stream();
+    }
+
+    /**
+     * Create an efficiently-splittable spliterator for the given path elements.
+     *
+     * <p>
+     * Since paths are so small, this is only useful for preventing heavy computations
+     * on later parts of the stream from occurring when using
+     * {@link Streams#findLast(IntStream)}, and not for parallelism.
+     * </p>
+     *
+     * @param path the path to create a spliterator for
+     * @return the spliterator
+     */
+    public static Spliterator<Path> optimizedSpliterator(Path path) {
+        return Arrays.spliterator(Streams.stream(path).toArray(Path[]::new));
+    }
+
+    private MorePaths() {
+    }
+}

worldedit-core/src/main/java/com/sk89q/worldedit/util/io/file/TrueVfsArchiveNioSupport.java

@@ -0,0 +1,59 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.util.io.file;
+
+import com.google.common.base.Splitter;
+import com.google.common.collect.ImmutableSet;
+import net.java.truevfs.access.TArchiveDetector;
+import net.java.truevfs.access.TPath;
+
+import java.io.IOException;
+import java.nio.file.Path;
+import java.util.Optional;
+import java.util.Set;
+
+public final class TrueVfsArchiveNioSupport implements ArchiveNioSupport {
+
+    private static final TrueVfsArchiveNioSupport INSTANCE = new TrueVfsArchiveNioSupport();
+
+    public static TrueVfsArchiveNioSupport getInstance() {
+        return INSTANCE;
+    }
+
+    private static final Set<String> ALLOWED_EXTENSIONS = ImmutableSet.copyOf(
+        Splitter.on('|').split(TArchiveDetector.ALL.getExtensions())
+    );
+
+    private TrueVfsArchiveNioSupport() {
+    }
+
+    @Override
+    public Optional<Path> tryOpenAsDir(Path archive) throws IOException {
+        String fileName = archive.getFileName().toString();
+        int dot = fileName.indexOf('.');
+        if (dot < 0 || dot >= fileName.length() || !ALLOWED_EXTENSIONS.contains(fileName.substring(dot + 1))) {
+            return Optional.empty();
+        }
+        TPath root = new TPath(archive).getFileSystem().getPath("/");
+        return Optional.of(ArchiveNioSupports.skipRootSameName(
+            root, fileName.substring(0, dot)
+        ));
+    }
+}

worldedit-core/src/main/java/com/sk89q/worldedit/util/io/file/ZipArchiveNioSupport.java

@@ -0,0 +1,53 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.util.io.file;
+
+import java.io.IOException;
+import java.nio.file.FileSystem;
+import java.nio.file.FileSystems;
+import java.nio.file.Path;
+import java.util.Optional;
+
+public final class ZipArchiveNioSupport implements ArchiveNioSupport {
+
+    private static final ZipArchiveNioSupport INSTANCE = new ZipArchiveNioSupport();
+
+    public static ZipArchiveNioSupport getInstance() {
+        return INSTANCE;
+    }
+
+    private ZipArchiveNioSupport() {
+    }
+
+    @Override
+    public Optional<Path> tryOpenAsDir(Path archive) throws IOException {
+        if (!archive.getFileName().toString().endsWith(".zip")) {
+            return Optional.empty();
+        }
+        FileSystem zipFs = FileSystems.newFileSystem(
+            archive, getClass().getClassLoader()
+        );
+        return Optional.of(ArchiveNioSupports.skipRootSameName(
+            zipFs.getPath("/"), archive.getFileName().toString()
+                .replaceFirst("\\.zip$", "")
+        ));
+    }
+
+}

worldedit-core/src/main/java/com/sk89q/worldedit/util/time/FileNameDateTimeParser.java

@@ -0,0 +1,110 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.util.time;
+
+import com.google.common.collect.Streams;
+import com.sk89q.worldedit.WorldEdit;
+import com.sk89q.worldedit.util.io.file.MorePaths;
+
+import javax.annotation.Nullable;
+import java.nio.file.Path;
+import java.time.ZoneId;
+import java.time.ZonedDateTime;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
+import java.util.stream.StreamSupport;
+
+/**
+ * Parses date-times by looking at the file name. File names without a time
+ * will use 00:00:00.
+ *
+ * <p>
+ * Elements may be separated by a space, dash, or colon.
+ * The date and time may additionally be separated by a 'T'.
+ * Only the year must have all digits, others may omit padding
+ * zeroes.
+ * </p>
+ *
+ * <p>
+ * Valid file name examples:
+ * <ul>
+ *     <li>{@code 2019-06-15}</li>
+ *     <li>{@code 2019-06-15 10:20:30}</li>
+ *     <li>{@code 2019-06-15 10:20:30}</li>
+ *     <li>{@code 2019-06-15T10:20:30}</li>
+ *     <li>{@code 2019 06 15 10 20 30}</li>
+ *     <li>{@code 2019-06-15-10-20-30}</li>
+ *     <li>{@code 2019-6-1-1-2-3}</li>
+ * </ul>
+ * </p>
+ */
+public class FileNameDateTimeParser implements SnapshotDateTimeParser {
+
+    private static final FileNameDateTimeParser INSTANCE = new FileNameDateTimeParser();
+
+    public static FileNameDateTimeParser getInstance() {
+        return INSTANCE;
+    }
+
+    private static final String SEP = "[ \\-_:]";
+
+    private static final Pattern BASIC_FILTER = Pattern.compile(
+        "^(?<year>\\d{4})" + SEP + "(?<month>\\d{1,2})" + SEP + "(?<day>\\d{1,2})" +
+            // Optionally:
+            "(?:" + "[ \\-_:T]" +
+            "(?<hour>\\d{1,2})" + SEP + "(?<minute>\\d{1,2})" + SEP + "(?<second>\\d{1,2})" +
+            ")?"
+    );
+
+    private FileNameDateTimeParser() {
+    }
+
+    @Nullable
+    @Override
+    public ZonedDateTime detectDateTime(Path path) {
+        // Make this perform a little better:
+        Matcher matcher = Streams.findLast(
+            StreamSupport.stream(MorePaths.optimizedSpliterator(path), false)
+                .map(p -> BASIC_FILTER.matcher(p.toString()))
+                .filter(Matcher::find)
+        ).orElse(null);
+        if (matcher != null) {
+            int year = matchAndParseOrZero(matcher, "year");
+            int month = matchAndParseOrZero(matcher, "month");
+            int day = matchAndParseOrZero(matcher, "day");
+            int hour = matchAndParseOrZero(matcher, "hour");
+            int minute = matchAndParseOrZero(matcher, "minute");
+            int second = matchAndParseOrZero(matcher, "second");
+            return ZonedDateTime.of(year, month, day, hour, minute, second,
+                0, ZoneId.systemDefault());
+        }
+        return null;
+    }
+
+    private static int matchAndParseOrZero(Matcher matcher, String group) {
+        String match = matcher.group(group);
+        if (match == null) {
+            return 0;
+        }
+        return Integer.parseInt(match);
+    }
+
+}

worldedit-core/src/main/java/com/sk89q/worldedit/util/time/ModificationDateTimeParser.java

@@ -0,0 +1,52 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.util.time;
+
+import java.io.IOException;
+import java.io.UncheckedIOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.time.ZoneId;
+import java.time.ZonedDateTime;
+
+public class ModificationDateTimeParser implements SnapshotDateTimeParser {
+
+    private static final ModificationDateTimeParser INSTANCE = new ModificationDateTimeParser();
+
+    public static ModificationDateTimeParser getInstance() {
+        return INSTANCE;
+    }
+
+    private ModificationDateTimeParser() {
+    }
+
+    @Override
+    public ZonedDateTime detectDateTime(Path path) {
+        if (!Files.exists(path)) {
+            return null;
+        }
+        try {
+            return Files.getLastModifiedTime(path).toInstant().atZone(ZoneId.systemDefault());
+        } catch (IOException e) {
+            throw new UncheckedIOException(e);
+        }
+    }
+
+}

worldedit-core/src/main/java/com/sk89q/worldedit/util/time/SnapshotDateTimeParser.java

@@ -0,0 +1,45 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.util.time;
+
+import javax.annotation.Nullable;
+import java.nio.file.Path;
+import java.time.ZonedDateTime;
+
+/**
+ * Instances of this interface try to determine an {@link ZonedDateTime} from a given
+ * {@link Path}.
+ */
+public interface SnapshotDateTimeParser {
+
+    /**
+     * Attempt to detect an ZonedDateTime from a path.
+     *
+     * <p>
+     * The path is not guaranteed to exist.
+     * </p>
+     *
+     * @param path the path
+     * @return date-time, if it can be parsed
+     */
+    @Nullable
+    ZonedDateTime detectDateTime(Path path);
+
+}

worldedit-core/src/main/java/com/sk89q/worldedit/util/translation/TranslationManager.java

@@ -19,8 +19,6 @@
 
 package com.sk89q.worldedit.util.translation;
 
-import static java.util.stream.Collectors.toMap;
-
 import com.google.common.collect.Maps;
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
@@ -29,6 +27,7 @@ import com.sk89q.worldedit.WorldEdit;
 import com.sk89q.worldedit.util.formatting.text.Component;
 import com.sk89q.worldedit.util.formatting.text.renderer.FriendlyComponentRenderer;
 import com.sk89q.worldedit.util.io.ResourceLoader;
+
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.IOException;
@@ -43,6 +42,8 @@ import java.util.Optional;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 
+import static java.util.stream.Collectors.toMap;
+
 /**
  * Handles translations for the plugin.
  *