Fix root Windows virtual_path issues

crates/nu-protocol/src/engine/state_working_set.rs

@@ -1003,14 +1003,17 @@ impl<'a> StateWorkingSet<'a> {
     }
 
     pub fn find_virtual_path(&self, name: &str) -> Option<&VirtualPath> {
+        // Platform appropriate virtual path (slashes or backslashes)
+        let virtual_path_name = Path::new(name);
+
         for (virtual_name, virtual_path) in self.delta.virtual_paths.iter().rev() {
-            if virtual_name == name {
+            if Path::new(virtual_name) == virtual_path_name {
                 return Some(virtual_path);
             }
         }
 
         for (virtual_name, virtual_path) in self.permanent_state.virtual_paths.iter().rev() {
-            if virtual_name == name {
+            if Path::new(virtual_name) == virtual_path_name {
                 return Some(virtual_path);
             }
         }

crates/nu-std/src/lib.rs

@@ -52,8 +52,8 @@ pub fn load_standard_library(
         let std_dir = std_dir.to_string_lossy().to_string();
         let source = r#"
 # Prelude
-use ([ std core ] | path join) *
-use ([ std deprecated_dirs] | path join) [
+use std/core *
+use std/deprecated_dirs [
     enter
     shells
     g

crates/nu-std/testing.nu

@@ -1,7 +1,7 @@
-use (['std', 'log'] | path join)
+use std/log
 export-env {
     # Place NU_FORMAT... environment variables in module-scope
-    export use (['std', 'log'] | path join) *
+    export use std/log *
 }
 
 def "nu-complete threads" [] {

tests/repl/test_stdlib.rs

@@ -7,8 +7,5 @@ fn not_loaded() -> TestResult {
 
 #[test]
 fn use_command() -> TestResult {
-    run_test_std(
-        "use ([ std, assert ] | path join); assert true; print 'it works'",
-        "it works",
-    )
+    run_test_std("use std/assert; assert true; print 'it works'", "it works")
 }

tests/shell/environment/env.rs

@@ -224,7 +224,7 @@ fn std_log_env_vars_are_not_overridden() {
             ("NU_LOG_DATE_FORMAT".to_string(), "%Y".to_string()),
         ],
         r#"
-            use ([ std, log] | path join)
+            use std/log
             print -e $env.NU_LOG_FORMAT
             print -e $env.NU_LOG_DATE_FORMAT
             log error "err"
@@ -237,7 +237,7 @@ fn std_log_env_vars_are_not_overridden() {
 fn std_log_env_vars_have_defaults() {
     let actual = nu_with_std!(
         r#"
-            use ([ std, log] | path join)
+            use std/log
             print -e $env.NU_LOG_FORMAT
             print -e $env.NU_LOG_DATE_FORMAT
         "#