Add DiagnosticTag support

org.eclipse.lsp4j/src/main/java/org/eclipse/lsp4j/DiagnosticTag.java

@@ -0,0 +1,48 @@
+/******************************************************************************
+ * Copyright (c) 2019 Microsoft.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0,
+ * or the Eclipse Distribution License v. 1.0 which is available at
+ * http://www.eclipse.org/org/documents/edl-v10.php.
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
+ ******************************************************************************/
+
+package org.eclipse.lsp4j;
+
+public enum DiagnosticTag {
+
+    /**
+     * Unused or unnecessary code.
+     *
+     * Clients are allowed to render diagnostics with this tag faded out instead of having
+     * an error squiggle.
+     */
+    Unnecessary(1),
+
+    /**
+     * Deprecated or obsolete code.
+     *
+     * Clients are allowed to rendered diagnostics with this tag strike through.
+     */
+    Deprecated(2);
+
+    private final int value;
+
+    DiagnosticTag(int value) {
+        this.value = value;
+    }
+
+    public int getValue() {
+        return value;
+    }
+
+    public static DiagnosticTag forValue(int value) {
+        DiagnosticTag[] allValues = DiagnosticTag.values();
+        if (value < 1 || value > allValues.length)
+            throw new IllegalArgumentException("Illegal enum value: " + value);
+        return allValues[value - 1];
+    }
+}

org.eclipse.lsp4j/src/main/java/org/eclipse/lsp4j/Protocol.xtend

@@ -1558,6 +1558,11 @@ class Diagnostic {
 	@NonNull
 	String message
 
+	/**
+	 * Additional metadata about the diagnostic.
+	 */
+	 List<DiagnosticTag> tags;
+
 	/**
 	 * An array of related diagnostic information, e.g. when symbol-names within a scope collide
 	 * all definitions can be marked via this property.

org.eclipse.lsp4j/src/main/xtend-gen/org/eclipse/lsp4j/Diagnostic.java

@@ -14,6 +14,7 @@
 import java.util.List;
 import org.eclipse.lsp4j.DiagnosticRelatedInformation;
 import org.eclipse.lsp4j.DiagnosticSeverity;
+import org.eclipse.lsp4j.DiagnosticTag;
 import org.eclipse.lsp4j.Range;
 import org.eclipse.lsp4j.jsonrpc.validation.NonNull;
 import org.eclipse.lsp4j.util.Preconditions;
@@ -53,6 +54,11 @@ public class Diagnostic {
   @NonNull
   private String message;
 
+  /**
+   * Additional metadata about the diagnostic.
+   */
+  private List<DiagnosticTag> tags;
+
   /**
    * An array of related diagnostic information, e.g. when symbol-names within a scope collide
    * all definitions can be marked via this property.
@@ -159,6 +165,21 @@ public void setMessage(@NonNull final String message) {
     this.message = Preconditions.checkNotNull(message, "message");
   }
 
+  /**
+   * Additional metadata about the diagnostic.
+   */
+  @Pure
+  public List<DiagnosticTag> getTags() {
+    return this.tags;
+  }
+
+  /**
+   * Additional metadata about the diagnostic.
+   */
+  public void setTags(final List<DiagnosticTag> tags) {
+    this.tags = tags;
+  }
+
   /**
    * An array of related diagnostic information, e.g. when symbol-names within a scope collide
    * all definitions can be marked via this property.
@@ -189,6 +210,7 @@ public String toString() {
     b.add("code", this.code);
     b.add("source", this.source);
     b.add("message", this.message);
+    b.add("tags", this.tags);
     b.add("relatedInformation", this.relatedInformation);
     return b.toString();
   }
@@ -228,6 +250,11 @@ public boolean equals(final Object obj) {
         return false;
     } else if (!this.message.equals(other.message))
       return false;
+    if (this.tags == null) {
+      if (other.tags != null)
+        return false;
+    } else if (!this.tags.equals(other.tags))
+      return false;
     if (this.relatedInformation == null) {
       if (other.relatedInformation != null)
         return false;
@@ -246,6 +273,7 @@ public int hashCode() {
     result = prime * result + ((this.code== null) ? 0 : this.code.hashCode());
     result = prime * result + ((this.source== null) ? 0 : this.source.hashCode());
     result = prime * result + ((this.message== null) ? 0 : this.message.hashCode());
+    result = prime * result + ((this.tags== null) ? 0 : this.tags.hashCode());
     return prime * result + ((this.relatedInformation== null) ? 0 : this.relatedInformation.hashCode());
   }
 }