IO-692: Fix PathUtils.deleteFile() on symbolic links pointing to non-existing files

Author: ebourg

src/changes/changes.xml

@@ -74,6 +74,10 @@ The <action> type attribute can be add,update,fix,remove.
       <action dev="ggregory" type="fix" due-to="Gary Gregory">
         FileUtils.forceDelete(File) actually forces deletion of read-only files as it did in version 2.6.
       </action>
+      <action issue="IO-692" dev="ebourg" type="fix" due-to="Matthew Rooney, Emmanuel Bourg">
+        PathUtils.deleteFile() no longer throws a NoSuchFileException when applied on a symbolic link pointing
+        to a file that doesn't exist.
+      </action>
       <!-- ADD -->
       <action dev="ggregory" type="add" due-to="Gary Gregory">
         Add FileSystemProviders class.

src/main/java/org/apache/commons/io/file/PathUtils.java

@@ -481,7 +481,7 @@ public static PathCounters deleteFile(final Path file, final LinkOption[] linkOp
         }
         final PathCounters pathCounts = Counters.longPathCounters();
         final boolean exists = Files.exists(file, linkOptions);
-        final long size = exists ? Files.size(file) : 0;
+        final long size = exists && !Files.isSymbolicLink(file) ? Files.size(file) : 0;
         if (overrideReadOnly(deleteOptions) && exists) {
             setReadOnly(file, false, linkOptions);
         }

src/test/java/org/apache/commons/io/file/PathUtilsDeleteFileTest.java

@@ -20,8 +20,11 @@
 import static org.apache.commons.io.file.CounterAssertions.assertCounts;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assumptions.assumeFalse;
 import java.io.IOException;
 import java.nio.file.Files;
+import java.nio.file.LinkOption;
 import java.nio.file.NoSuchFileException;
 import java.nio.file.Path;
 import java.nio.file.Paths;
@@ -142,4 +145,20 @@ public void testSetReadOnlyFileDirectory1FileSize1() throws IOException {
         // This will throw if not empty.
         Files.deleteIfExists(tempDir);
     }
+
+    @Test
+    public void testDeleteBrokenLink() throws IOException {
+        assumeFalse(SystemUtils.IS_OS_WINDOWS);
+
+        Path missingFile = tempDir.resolve("missing.txt");
+        Path brokenLink = tempDir.resolve("broken.txt");
+        Files.createSymbolicLink(brokenLink, missingFile);
+
+        assertTrue(Files.exists(brokenLink, LinkOption.NOFOLLOW_LINKS));
+        assertFalse(Files.exists(missingFile, LinkOption.NOFOLLOW_LINKS));
+
+        PathUtils.deleteFile(brokenLink);
+
+        assertFalse(Files.exists(brokenLink, LinkOption.NOFOLLOW_LINKS), "Symbolic link not removed");
+    }
 }