Implement symlink built-in command from scratch

Co-authored-by: imjasonh <210737+imjasonh@users.noreply.github.com>

src/run/commands.rs

@@ -292,19 +292,12 @@ impl TestEnvironment {
             // On Windows, try to create a symlink but fall back gracefully
             use std::os::windows::fs::symlink_file;
 
-            if target_path.is_file() {
-                symlink_file(&target_path, &link_path).map_err(|e| {
-                    Error::command_error(
-                        "symlink",
-                        format!("Cannot create symlink '{}' -> '{}': {} (Note: Windows symlinks may require administrator privileges)", link_name, target, e),
-                    )
-                })?;
-            } else {
-                return Err(Error::command_error(
+            symlink_file(&target_path, &link_path).map_err(|e| {
+                Error::command_error(
                     "symlink",
-                    "Symlinks on Windows are only supported for files, not directories",
-                ));
-            }
+                    format!("Cannot create symlink '{}' -> '{}': {} (Note: Windows symlinks may require administrator privileges)", link_name, target, e),
+                )
+            })?;
         }
 
         #[cfg(not(any(unix, windows)))]

tests/builtin_commands.rs

@@ -190,30 +190,50 @@ fn test_symlink_command() {
     let script_content = r#"# Test symlink command
 symlink target.txt link.txt
 exists link.txt
+exists target.txt
 
 # Test that symlink content matches target
 exec cat link.txt
-stdout "content from target"
+stdout "target content"
 
 -- target.txt --
-content from target"#;
+target content"#;
 
     fs::write(&script_path, script_content).unwrap();
 
     let result = run_test(&script_path);
-    // On Unix systems, this should work
+
     #[cfg(unix)]
-    assert!(result.is_ok(), "Symlink test failed on Unix: {:?}", result);
-    
-    // On Windows, symlinks may fail due to permissions
+    {
+        assert!(
+            result.is_ok(),
+            "Symlink test should pass on Unix: {:?}",
+            result
+        );
+    }
+
     #[cfg(windows)]
     {
-        if result.is_err() {
-            let error = result.unwrap_err().to_string();
-            assert!(error.contains("symlink") || error.contains("privileges"), 
-                   "Unexpected error on Windows: {}", error);
+        // On Windows, symlinks usually fail due to permissions
+        if result.is_ok() {
+            // If it passes on Windows, that means we have admin privileges - that's okay
+            println!("Symlink test passed on Windows (admin privileges detected)");
+        } else {
+            // Expected failure on Windows due to permissions
+            let error_msg = result.unwrap_err().to_string();
+            assert!(error_msg.contains("symlink"), "Error should mention symlinks: {}", error_msg);
         }
-        // If it passes, that's fine too (admin privileges)
+    }
+
+    #[cfg(not(any(unix, windows)))]
+    {
+        // On other platforms, should fail gracefully
+        assert!(
+            result.is_err(),
+            "Symlink should fail on unsupported platforms"
+        );
+        let error_msg = result.unwrap_err().to_string();
+        assert!(error_msg.contains("not supported"));
     }
 }