#1788: Created a commandlet to simulate the behaviour of ln -s

.editorconfig

@@ -18,7 +18,7 @@ ij_wrap_on_typing = false
 
 [*.properties]
 ij_properties_align_group_field_declarations = false
-ij_properties_keep_blank_lines = true
+ij_properties_keep_blank_lines = false
 ij_properties_key_value_delimiter = equals
 ij_properties_spaces_around_key_value_delimiter = false
 
@@ -354,4 +354,4 @@ ij_yaml_keep_line_breaks = true
 ij_yaml_sequence_on_new_line = false
 ij_yaml_space_before_colon = false
 ij_yaml_spaces_within_braces = true
-ij_yaml_spaces_within_brackets = true
+ij_yaml_spaces_within_brackets = true

.gitignore

@@ -14,7 +14,6 @@
 !.anyedit.properties
 !.ide.properties
 !.templateengine
-!.github
 target/
 eclipse-target/
 generated/

CHANGELOG.adoc

@@ -20,6 +20,7 @@ Release with new features and bugfixes:
 * https://github.com/devonfw/IDEasy/issues/1834[#1834]: Fix fix-vpn-tls-problem NullPointerException
 * https://github.com/devonfw/IDEasy/issues/1724[#1724]: Add gui commandlet
 * https://github.com/devonfw/IDEasy/issues/1853[#1853]: Add ARM releases for VSCode on Mac
+* https://github.com/devonfw/IDEasy/issues/1788[#1788]: Add Commandlet to create links
 * https://github.com/devonfw/IDEasy/issues/797[#797]: Use system unzip on macOS to preserve symlinks in ZIP extraction
 * https://github.com/devonfw/IDEasy/issues/1723[#1723]: Add commandlet for GitHub Copilot CLI
 * https://github.com/devonfw/IDEasy/issues/1880[#1880]: Reinstall all plugins for IDE in force mode

cli/src/main/java/com/devonfw/tools/ide/commandlet/CommandletManagerImpl.java

@@ -108,6 +108,7 @@ public CommandletManagerImpl(IdeContext context) {
     add(new StatusCommandlet(context));
     add(new RepositoryCommandlet(context));
     add(new UninstallCommandlet(context));
+    add(new LnCommandlet(context));
     add(new UpdateCommandlet(context));
     add(new UpgradeSettingsCommandlet(context));
     add(new CreateCommandlet(context));

cli/src/main/java/com/devonfw/tools/ide/commandlet/LnCommandlet.java

@@ -0,0 +1,91 @@
+package com.devonfw.tools.ide.commandlet;
+
+import java.nio.file.Files;
+import java.nio.file.Path;
+
+import com.devonfw.tools.ide.cli.CliException;
+import com.devonfw.tools.ide.context.IdeContext;
+import com.devonfw.tools.ide.io.PathLinkType;
+import com.devonfw.tools.ide.property.FlagProperty;
+import com.devonfw.tools.ide.property.PathProperty;
+
+/**
+ * // * Link creation {@link Commandlet} similar to {@code ln -s}.
+ * <p>
+ * It tries to create a true symbolic link first. On Windows, symlink creation may be restricted due to missing privileges. In that case, IDEasy will create a
+ * hard link as an alternative (file-only, same volume) to avoid the Git-Bash behavior of silently copying files.
+ */
+public final class LnCommandlet extends Commandlet {
+
+  /** Grammar token {@code -s} (optional). */
+  public final FlagProperty symbolic;
+
+  /** Grammar token {@code -r} (optional). */
+  public final FlagProperty relative;
+
+  /** The source path to link to. */
+  public final PathProperty source;
+
+  /** The target path (the created link). */
+  public final PathProperty link;
+
+  /**
+   * The constructor.
+   *
+   * @param context the {@link IdeContext}.
+   */
+  public LnCommandlet(IdeContext context) {
+
+    super(context);
+    addKeyword(getName());
+
+    this.symbolic = add(new FlagProperty("--symbolic", false, "-s"));
+    this.relative = add(new FlagProperty("--relative", false, "-r"));
+    this.source = add(new PathProperty("", true, "source", true));
+    this.link = add(new PathProperty("", true, "link", true));
+  }
+
+  @Override
+  public String getName() {
+
+    return "ln";
+  }
+
+  @Override
+  public boolean isIdeRootRequired() {
+
+    return false;
+  }
+
+  @Override
+  public boolean isIdeHomeRequired() {
+
+    return false;
+  }
+
+  @Override
+  public boolean isWriteLogFile() {
+
+    return false;
+  }
+
+  @Override
+  protected void doRun() {
+
+    Path cwd = this.context.getCwd();
+    if (cwd == null) {
+      throw new CliException("Missing current working directory!");
+    }
+
+    Path sourcePath = cwd.resolve(this.source.getValue()).normalize();
+    Path linkPath = cwd.resolve(this.link.getValue()).normalize();
+    boolean relative = this.relative.isTrue();
+
+    if (!Files.exists(sourcePath)) {
+      throw new CliException("Source does not exist: " + sourcePath);
+    }
+
+    PathLinkType linkType = this.symbolic.isTrue() ? PathLinkType.SYMBOLIC_LINK : PathLinkType.HARD_LINK;
+    this.context.getFileAccess().link(sourcePath, linkPath, relative, linkType, this.context.isForceMode());
+  }
+}

cli/src/main/java/com/devonfw/tools/ide/io/FileAccess.java

@@ -132,13 +132,28 @@ default void hardlink(Path source, Path link) {
    * @param relative - {@code true} if the link shall be relative, {@code false} if it shall be absolute.
    * @param type the {@link PathLinkType}.
    */
-  void link(Path source, Path link, boolean relative, PathLinkType type);
+  default void link(Path source, Path link, boolean relative, PathLinkType type) {
+    link(source, link, relative, type, true);
+  }
+
+  /**
+   * Creates a link. If the given {@code link} already exists and is a symbolic link or a Windows junction, it will be replaced if {@code override} is
+   * {@code true}. In case of missing privileges, Windows mklink may be used as fallback, which must point to absolute paths. In such case the {@code relative}
+   * flag will be ignored.
+   *
+   * @param source the source {@link Path} to link to, may be relative or absolute.
+   * @param link the destination {@link Path} where the link shall be created pointing to {@code source}.
+   * @param relative - {@code true} if the link shall be relative, {@code false} if it shall be absolute.
+   * @param type the {@link PathLinkType}.
+   * @param override - {@code true} to override existing links, {@code false} otherwise.
+   */
+  void link(Path source, Path link, boolean relative, PathLinkType type, boolean override);
 
   /**
    * @param link the {@link PathLink} to {@link #link(Path, Path, boolean, PathLinkType) create}.
    */
   default void link(PathLink link) {
-    link(link.source(), link.link(), true, link.type());
+    link(link.source(), link.link(), true, link.type(), true);
   }
 
   /**

cli/src/main/java/com/devonfw/tools/ide/io/FileAccessImpl.java

@@ -527,7 +527,7 @@ private boolean runMklink(Path source, Path link, Path cwd, String option) {
   }
 
   @Override
-  public void link(Path source, Path link, boolean relative, PathLinkType type) {
+  public void link(Path source, Path link, boolean relative, PathLinkType type, boolean override) {
 
     Path finalLink = link.toAbsolutePath().normalize();
     Path finalSource;
@@ -539,13 +539,15 @@ public void link(Path source, Path link, boolean relative, PathLinkType type) {
     Path absoluteSource = finalSource.isAbsolute() ? finalSource : finalLink.getParent().resolve(finalSource).normalize();
     String relativeOrAbsolute = relative ? "relative" : "absolute";
     LOG.debug("Creating {} {} at {} pointing to {}", relativeOrAbsolute, type, finalLink, finalSource);
-    deleteLinkIfExists(finalLink);
+    if (override) {
+      deleteLinkIfExists(finalLink);
+    }
     try {
       // Attention: JavaDoc and position of path arguments can be very confusing - see comment in #1736
       if (type == PathLinkType.SYMBOLIC_LINK) {
         Files.createSymbolicLink(finalLink, finalSource);
       } else if (type == PathLinkType.HARD_LINK) {
-        Files.createLink(finalLink, finalSource);
+        createHardLink(finalSource, finalLink, override);
       } else {
         throw new IllegalStateException("" + type);
       }
@@ -555,7 +557,13 @@ public void link(Path source, Path link, boolean relative, PathLinkType type) {
             "Due to lack of permissions, Microsoft's mklink with junction had to be used to create a Symlink. See\n"
                 + "https://github.com/devonfw/IDEasy/blob/main/documentation/symlink.adoc for further details. Error was: "
                 + e.getMessage());
-        mklinkOnWindows(finalSource, absoluteSource, finalLink, type, relative);
+
+        try {
+          mklinkOnWindows(finalSource, absoluteSource, finalLink, type, relative);
+        } catch (IllegalStateException mkEx) {
+          LOG.info("Creating a hard link as a fallback for the failed mklink attempt.");
+          createHardLink(absoluteSource, finalLink, override);
+        }
       } else {
         throw new RuntimeException(e);
       }
@@ -564,6 +572,26 @@ public void link(Path source, Path link, boolean relative, PathLinkType type) {
     }
   }
 
+
+  /**
+   * Creates a hard link at {@code link} pointing to {@code source}.
+   *
+   * @param source the {@link Path} the hard link will point to.
+   * @param link the {@link Path} where to create the hard link.
+   * @param override - {@code true} to override existing links, {@code false} otherwise.
+   */
+  void createHardLink(Path source, Path link, boolean override) {
+    if (override && Files.exists(link, LinkOption.NOFOLLOW_LINKS)) {
+      delete(link);
+    }
+    try {
+      Files.createLink(link, source);
+      LOG.trace("Created hard link at {} pointing to {}", link, source);
+    } catch (IOException e) {
+      throw new RuntimeException("Failed to create a hardlink for " + source + " at " + link, e);
+    }
+  }
+
   @Override
   public Path getPathStart(Path path, int nameEnd) {
 

cli/src/main/resources/nls/Help.properties

@@ -83,6 +83,8 @@ cmd.list-editions=List the available editions of the selected tool.
 cmd.list-editions.detail=To list all available editions of e.g. 'intellij' simply type: 'ide list-editions intellij'.
 cmd.list-versions=List the available versions of the selected tool.
 cmd.list-versions.detail=To list all available versions of e.g. 'intellij' simply type: 'ide list-versions intellij'.
+cmd.ln=Create a symbolic or hard link.
+cmd.ln.detail=Creates a link similar to the command "ln" but working cross-platform (unlike in git-bash on Windows that typically only creates a copy).
 cmd.mvn=Tool commandlet for Maven (Build-Tool).
 cmd.mvn.detail=Apache Maven is a build automation and dependency management tool for Java projects. Detailed documentation can be found at https://maven.apache.org/guides/index.html
 cmd.nest=Tool commandlet for Nest CLI.
@@ -165,9 +167,11 @@ opt.--no-colors=disable colored log messages.
 opt.--offline=enable offline mode (skip updates or git pull, fail downloads or git clone).
 opt.--privacy=enable GDPR-compliant console output.
 opt.--quiet=disable info logging (only log success, warning or error).
+opt.--relative=use relative paths.
 opt.--skip-repositories=skip the setup of repositories.
 opt.--skip-tools=skip the installation/update of tools.
 opt.--skip-updates=disables tool updates if the configured versions match the installed versions.
+opt.--symbolic=Create a symbolic link instead of a hard link (default).
 opt.--trace=enable trace logging.
 opt.--version=Print the IDE version and exit.
 options.global=Global options:
@@ -178,8 +182,10 @@ val.args=The commandline arguments to pass to the tool.
 val.cfg=Selection of the configuration file (settings | home | conf | workspace).
 val.commandlet=The selected commandlet (use 'ide help' to list all commandlets).
 val.edition=The tool edition.
+val.link=The path where the link is created.
 val.plugin=The plugin to select
 val.settingsRepository=The settings git repository with the IDEasy configuration for the project.
+val.source=The source path the link points to (existing file or directory).
 val.tool=The tool commandlet to select.
 val.version=The tool version.
 values=Values:

cli/src/main/resources/nls/Help_de.properties

@@ -83,6 +83,8 @@ cmd.list-editions=Listet die verfügbaren Editionen des selektierten Werkzeugs a
 cmd.list-editions.detail=Um alle verfügbaren Editionen von z.B. 'intellij' aufzulisten, geben Sie einfach 'ide list-editions intellij' in die Konsole ein.
 cmd.list-versions=Listet die verfügbaren Versionen des selektierten Werkzeugs auf.
 cmd.list-versions.detail=Um alle verfügbaren Versionen von z.B. 'intellij' aufzulisten, geben Sie einfach 'ide list-versions intellij' in die Konsole ein.
+cmd.ln=Erstellt einen symbolischen oder harten Link
+cmd.ln.detail=Erstellt einen Link wie das Kommando "ln" jedoch plattform-übergreifend (anders als in Git-Bash unter Windows wo typischerweise nur eine Kopie erstellt wird).
 cmd.mvn=Werkzeug Kommando für Maven (Build-Werkzeug).
 cmd.mvn.detail=Apache Maven ist ein Build-Automatisierungs- und Abhängigkeitsverwaltungstool für Java-Projekte. Detaillierte Dokumentation ist zu finden unter https://maven.apache.org/guides/index.html
 cmd.nest=Werkzeug Kommando für Nest CLI.
@@ -165,9 +167,11 @@ opt.--no-colors=Deaktiviert farbige Log-Meldungen.
 opt.--offline=Aktiviert den Offline-Modus (Überspringt Aktualisierungen oder git pull, schlägt fehl bei Downloads or git clone).
 opt.--privacy=Aktiviert DSGVO konforme Konsolenausgaben.
 opt.--quiet=Deaktiviert Info Logging ( nur success, warning und error).
+opt.--relative=Relative Pfade verwenden.
 opt.--skip-repositories=Überspringt die Einrichtung der Repositories.
 opt.--skip-tools=Überspringt die Installation/Aktualisierung der Tools.
 opt.--skip-updates=Deaktiviert Aktualisierungen von Tools wenn die installierten Versionen mit den konfigurierten Versionen übereinstimmen.
+opt.--symbolic=Erstellt einen symbolischen Link anstelle eines Hardlinks (Standard).
 opt.--trace=Aktiviert Trace-Ausgaben (detaillierte Fehleranalyse).
 opt.--version=Zeigt die IDE Version an und beendet das Programm.
 options.global=Globale Optionen:
@@ -178,8 +182,10 @@ val.args=Die Kommandozeilen-Argumente zur Übergabe an das Werkzeug.
 val.cfg=Auswahl der Konfigurationsdatei (settings | home | conf | workspace).
 val.commandlet=Das ausgewählte Commandlet ("ide help" verwenden, um alle Commandlets aufzulisten).
 val.edition=Die Werkzeug Edition.
+val.link=Pfad des zu erstellenden Links.
 val.plugin=Die zu selektierende Erweiterung.
 val.settingsRepository=Das settings git Repository mit den IDEasy Einstellungen für das Projekt.
+val.source=Ziel des Links (existierender Pfad).
 val.tool=Das zu selektierende Werkzeug Kommando.
 val.version=Die Werkzeug Version.
 values=Werte: