Allow symlink creation through symlinked dirs in preserve-local

tests/Import/FilesSyncStateTest.php

@@ -368,4 +368,92 @@ public function testFetchStageOverwritesPreviouslySyncedFile()
             "Fetch stage must overwrite existing files that were placed in the download list",
         );
     }
+
+    // ---------------------------------------------------------------
+    // Symlink in site-owned dir (WP Cloud Atomic theme layout)
+    // ---------------------------------------------------------------
+
+    /**
+     * A symlink entry at a site-owned path (no symlinks in the parent
+     * chain) should be added to the download list in preserve-local
+     * mode, even when its target points through a shared directory.
+     *
+     * WP Cloud Atomic layout: wp-content/themes/indice is the per-site
+     * symlink (site-owned), pointing to ../../wordpress/themes/pub/indice
+     * (shared infrastructure).  The parent wp-content/themes/ has no
+     * symlinks in its path, so preserve-local allows it.
+     */
+    public function testDeltaDiffIncludesSymlinkInSiteOwnedDir()
+    {
+        // Site-owned directory — no symlinks in path
+        mkdir($this->fs_root . '/wp-content/themes', 0755, true);
+
+        // Shared infrastructure (not traversed for the symlink's parent)
+        mkdir($this->fs_root . '/wp-shared/themes/pub/indice', 0755, true);
+        symlink('wp-shared', $this->fs_root . '/wordpress');
+
+        $localIndex = $this->stateDir . '/.import-index.jsonl';
+        file_put_contents($localIndex, '');
+
+        $remoteIndex = $this->stateDir . '/.import-remote-index.jsonl';
+        file_put_contents($remoteIndex, $this->indexLine('/wp-content/themes/indice', 1000, 0, 'link'));
+
+        $this->writeState([
+            "command" => "files-pull",
+            "status" => "in_progress",
+            "stage" => "diff",
+        ]);
+
+        [$client, $reflection] = $this->prepareClient();
+        $reflection->getMethod('diff_indexes_and_build_fetch_list')->invoke($client);
+
+        $downloads = $this->readDownloadList();
+        $this->assertContains(
+            '/wp-content/themes/indice',
+            $downloads,
+            "Symlink in site-owned directory must be added to the download list",
+        );
+    }
+
+    /**
+     * Entries whose parent path traverses a symlink should be blocked
+     * regardless of entry type — the parent directory is shared
+     * infrastructure.
+     */
+    public function testDeltaDiffSkipsEntriesInsideSharedDir()
+    {
+        mkdir($this->fs_root . '/wp-shared/themes/pub', 0755, true);
+        symlink('wp-shared', $this->fs_root . '/wordpress');
+
+        $localIndex = $this->stateDir . '/.import-index.jsonl';
+        file_put_contents($localIndex, '');
+
+        $remoteIndex = $this->stateDir . '/.import-remote-index.jsonl';
+        file_put_contents(
+            $remoteIndex,
+            $this->indexLine('/wordpress/themes/pub/indice', 1000, 0, 'link') .
+            $this->indexLine('/wordpress/themes/pub/indice/style.css', 1000, 500, 'file'),
+        );
+
+        $this->writeState([
+            "command" => "files-pull",
+            "status" => "in_progress",
+            "stage" => "diff",
+        ]);
+
+        [$client, $reflection] = $this->prepareClient();
+        $reflection->getMethod('diff_indexes_and_build_fetch_list')->invoke($client);
+
+        $downloads = $this->readDownloadList();
+        $this->assertNotContains(
+            '/wordpress/themes/pub/indice',
+            $downloads,
+            "Symlink inside shared directory must be skipped",
+        );
+        $this->assertNotContains(
+            '/wordpress/themes/pub/indice/style.css',
+            $downloads,
+            "File inside shared directory must be skipped",
+        );
+    }
 }

tests/Import/ImportSymlinkTest.php

@@ -289,4 +289,92 @@ public function testSymlinkReplacesExistingFile()
         $this->assertTrue(is_link($filePath), 'File should be replaced with symlink');
         $this->assertEquals('target', readlink($filePath));
     }
+
+    /**
+     * In preserve-local mode, a symlink whose parent directory is
+     * site-owned (no symlinks in the path) should be created even when
+     * its target points through a symlinked shared directory.
+     *
+     * This is the WP Cloud Atomic theme layout: the per-site symlink
+     * lives at wp-content/themes/indice (site-owned) and points to
+     * ../../wordpress/themes/pub/indice (shared infrastructure reached
+     * through the /wordpress/ symlink).  The target path is validated
+     * by normalize_path (string-only, no symlink resolution), so it
+     * stays within the fs-root and passes.
+     */
+    public function testPreserveLocalAllowsSymlinkPointingThroughSharedDir()
+    {
+        $fsRoot = $this->tempDir . '/fs-root';
+
+        // Site-owned themes directory (no symlinks in path)
+        mkdir($fsRoot . '/wp-content/themes', 0755, true);
+
+        // Shared infrastructure: wordpress/ is a symlink
+        mkdir($fsRoot . '/wp-shared/themes/pub/indice', 0755, true);
+        symlink('wp-shared', $fsRoot . '/wordpress');
+
+        $client = new \ImportClient('http://fake.url', $this->tempDir, $fsRoot);
+
+        $reflection = new \ReflectionClass($client);
+        $behaviorProp = $reflection->getProperty('fs_root_nonempty_behavior');
+        $behaviorProp->setValue($client, 'preserve-local');
+
+        $method = $reflection->getMethod('handle_symlink_chunk');
+
+        // Target points through the shared /wordpress/ symlink
+        $chunk = [
+            'headers' => [
+                'x-symlink-path' => base64_encode('/wp-content/themes/indice'),
+                'x-symlink-target' => base64_encode('../../wordpress/themes/pub/indice'),
+                'x-symlink-ctime' => '1234567890'
+            ]
+        ];
+
+        $method->invoke($client, $chunk);
+
+        $symlinkPath = $fsRoot . '/wp-content/themes/indice';
+        $this->assertTrue(is_link($symlinkPath), 'Symlink in site-owned dir should be created');
+        $this->assertEquals(
+            '../../wordpress/themes/pub/indice',
+            readlink($symlinkPath),
+        );
+    }
+
+    /**
+     * In preserve-local mode, a symlink whose parent IS a shared
+     * directory (reached through a symlink) should be blocked — both
+     * files and symlinks modify the shared directory equally.
+     */
+    public function testPreserveLocalBlocksSymlinkInsideSharedDir()
+    {
+        $fsRoot = $this->tempDir . '/fs-root';
+
+        mkdir($fsRoot . '/wp-shared/themes/pub', 0755, true);
+        symlink('wp-shared', $fsRoot . '/wordpress');
+
+        $client = new \ImportClient('http://fake.url', $this->tempDir, $fsRoot);
+
+        $reflection = new \ReflectionClass($client);
+        $behaviorProp = $reflection->getProperty('fs_root_nonempty_behavior');
+        $behaviorProp->setValue($client, 'preserve-local');
+
+        $method = $reflection->getMethod('handle_symlink_chunk');
+
+        // Parent path traverses /wordpress/ symlink → shared territory
+        $chunk = [
+            'headers' => [
+                'x-symlink-path' => base64_encode('/wordpress/themes/pub/indice'),
+                'x-symlink-target' => base64_encode('indice-1.0'),
+                'x-symlink-ctime' => '1234567890'
+            ]
+        ];
+
+        $method->invoke($client, $chunk);
+
+        $symlinkPath = $fsRoot . '/wordpress/themes/pub/indice';
+        $this->assertFalse(
+            is_link($symlinkPath),
+            'Symlink inside shared directory (through symlink) must be blocked',
+        );
+    }
 }