Path migration 1 (#13309)

# Description
Part 1 of replacing `std::path` types with `nu_path` types added in
#13115.

crates/nu-cli/src/repl.rs

@@ -336,6 +336,7 @@ fn loop_iteration(ctx: LoopContext) -> (bool, Stack, Reedline) {
         .with_cwd(Some(
             engine_state
                 .cwd(None)
+                .map(|cwd| cwd.into_std_path_buf())
                 .unwrap_or_default()
                 .to_string_lossy()
                 .to_string(),

crates/nu-cmd-base/src/util.rs

@@ -1,3 +1,4 @@
+use nu_path::AbsolutePathBuf;
 use nu_protocol::{
     engine::{EngineState, Stack},
     Range, ShellError, Span, Value,
@@ -15,6 +16,7 @@ pub fn get_init_cwd() -> PathBuf {
 pub fn get_guaranteed_cwd(engine_state: &EngineState, stack: &Stack) -> PathBuf {
     engine_state
         .cwd(Some(stack))
+        .map(AbsolutePathBuf::into_std_path_buf)
         .unwrap_or(crate::util::get_init_cwd())
 }
 

crates/nu-command/src/env/config/config_env.rs

@@ -60,12 +60,13 @@ impl Command for ConfigEnv {
         let (editor_name, editor_args) = get_editor(engine_state, stack, call.head)?;
         let paths = nu_engine::env::path_str(engine_state, stack, call.head)?;
         let cwd = engine_state.cwd(Some(stack))?;
-        let editor_executable =
-            crate::which(&editor_name, &paths, &cwd).ok_or(ShellError::ExternalCommand {
+        let editor_executable = crate::which(&editor_name, &paths, cwd.as_ref()).ok_or(
+            ShellError::ExternalCommand {
                 label: format!("`{editor_name}` not found"),
                 help: "Failed to find the editor executable".into(),
                 span: call.head,
-            })?;
+            },
+        )?;
 
         let Some(env_path) = engine_state.get_config_path("env-path") else {
             return Err(ShellError::GenericError {

crates/nu-command/src/env/config/config_nu.rs

@@ -64,12 +64,13 @@ impl Command for ConfigNu {
         let (editor_name, editor_args) = get_editor(engine_state, stack, call.head)?;
         let paths = nu_engine::env::path_str(engine_state, stack, call.head)?;
         let cwd = engine_state.cwd(Some(stack))?;
-        let editor_executable =
-            crate::which(&editor_name, &paths, &cwd).ok_or(ShellError::ExternalCommand {
+        let editor_executable = crate::which(&editor_name, &paths, cwd.as_ref()).ok_or(
+            ShellError::ExternalCommand {
                 label: format!("`{editor_name}` not found"),
                 help: "Failed to find the editor executable".into(),
                 span: call.head,
-            })?;
+            },
+        )?;
 
         let Some(config_path) = engine_state.get_config_path("config-path") else {
             return Err(ShellError::GenericError {

crates/nu-command/src/filesystem/cd.rs

@@ -1,5 +1,6 @@
 use nu_cmd_base::util::get_init_cwd;
 use nu_engine::command_prelude::*;
+use nu_path::AbsolutePathBuf;
 use nu_utils::filesystem::{have_permission, PermissionResult};
 
 #[derive(Clone)]
@@ -43,7 +44,10 @@ impl Command for Cd {
 
         // If getting PWD failed, default to the initial directory. This way, the
         // user can use `cd` to recover PWD to a good state.
-        let cwd = engine_state.cwd(Some(stack)).unwrap_or(get_init_cwd());
+        let cwd = engine_state
+            .cwd(Some(stack))
+            .map(AbsolutePathBuf::into_std_path_buf)
+            .unwrap_or(get_init_cwd());
 
         let path_val = {
             if let Some(path) = path_val {

crates/nu-command/src/path/type.rs

@@ -1,13 +1,11 @@
 use super::PathSubcommandArguments;
 use nu_engine::command_prelude::*;
+use nu_path::AbsolutePathBuf;
 use nu_protocol::engine::StateWorkingSet;
-use std::{
-    io,
-    path::{Path, PathBuf},
-};
+use std::{io, path::Path};
 
 struct Arguments {
-    pwd: PathBuf,
+    pwd: AbsolutePathBuf,
 }
 
 impl PathSubcommandArguments for Arguments {}

crates/nu-command/src/system/exec.rs

@@ -39,7 +39,7 @@ On Windows based systems, Nushell will wait for the command to finish and then e
         let name: Spanned<String> = call.req(engine_state, stack, 0)?;
         let executable = {
             let paths = nu_engine::env::path_str(engine_state, stack, call.head)?;
-            let Some(executable) = crate::which(&name.item, &paths, &cwd) else {
+            let Some(executable) = crate::which(&name.item, &paths, cwd.as_ref()) else {
                 return Err(crate::command_not_found(
                     &name.item,
                     call.head,

crates/nu-command/src/system/run_external.rs

@@ -79,7 +79,7 @@ impl Command for External {
             // Determine the PATH to be used and then use `which` to find it - though this has no
             // effect if it's an absolute path already
             let paths = nu_engine::env::path_str(engine_state, stack, call.head)?;
-            let Some(executable) = which(expanded_name, &paths, &cwd) else {
+            let Some(executable) = which(expanded_name, &paths, cwd.as_ref()) else {
                 return Err(command_not_found(&name_str, call.head, engine_state, stack));
             };
             executable
@@ -228,7 +228,7 @@ pub fn eval_arguments_from_call(
             match arg {
                 // Expand globs passed to run-external
                 Value::Glob { val, no_expand, .. } if !no_expand => args.extend(
-                    expand_glob(&val, &cwd, expr.span, engine_state.signals())?
+                    expand_glob(&val, cwd.as_ref(), expr.span, engine_state.signals())?
                         .into_iter()
                         .map(|s| s.into_spanned(expr.span)),
                 ),

crates/nu-command/src/viewers/griddle.rs

@@ -83,7 +83,7 @@ prints out the list properly."#
                         separator_param,
                         env_str,
                         use_grid_icons,
-                        &cwd,
+                        cwd.as_ref(),
                     )?)
                 } else {
                     Ok(PipelineData::empty())
@@ -101,7 +101,7 @@ prints out the list properly."#
                         separator_param,
                         env_str,
                         use_grid_icons,
-                        &cwd,
+                        cwd.as_ref(),
                     )?)
                 } else {
                     // dbg!(data);
@@ -124,7 +124,7 @@ prints out the list properly."#
                     separator_param,
                     env_str,
                     use_grid_icons,
-                    &cwd,
+                    cwd.as_ref(),
                 )?)
             }
             x => {

crates/nu-engine/src/eval.rs

@@ -1,6 +1,6 @@
 #[allow(deprecated)]
 use crate::{current_dir, get_config, get_full_help};
-use nu_path::expand_path_with;
+use nu_path::{expand_path_with, AbsolutePathBuf};
 use nu_protocol::{
     ast::{
         Assignment, Block, Call, Expr, Expression, ExternalArgument, PathMember, PipelineElement,
@@ -679,7 +679,10 @@ impl Eval for EvalRuntime {
         } else if quoted {
             Ok(Value::string(path, span))
         } else {
-            let cwd = engine_state.cwd(Some(stack)).unwrap_or_default();
+            let cwd = engine_state
+                .cwd(Some(stack))
+                .map(AbsolutePathBuf::into_std_path_buf)
+                .unwrap_or_default();
             let path = expand_path_with(path, cwd, true);
 
             Ok(Value::string(path.to_string_lossy(), span))

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

@@ -12,6 +12,7 @@ use crate::{
 };
 use fancy_regex::Regex;
 use lru::LruCache;
+use nu_path::AbsolutePathBuf;
 use std::{
     collections::HashMap,
     num::NonZeroUsize,
@@ -922,58 +923,44 @@ impl EngineState {
     ///
     /// If `stack` is supplied, also considers modifications to the working
     /// directory on the stack that have yet to be merged into the engine state.
-    pub fn cwd(&self, stack: Option<&Stack>) -> Result<PathBuf, ShellError> {
+    pub fn cwd(&self, stack: Option<&Stack>) -> Result<AbsolutePathBuf, ShellError> {
         // Helper function to create a simple generic error.
-        fn error(msg: &str, cwd: impl AsRef<Path>) -> Result<PathBuf, ShellError> {
-            Err(ShellError::GenericError {
+        fn error(msg: &str, cwd: impl AsRef<nu_path::Path>) -> ShellError {
+            ShellError::GenericError {
                 error: msg.into(),
                 msg: format!("$env.PWD = {}", cwd.as_ref().display()),
                 span: None,
                 help: Some("Use `cd` to reset $env.PWD into a good state".into()),
                 inner: vec![],
-            })
             }
-
-        // Helper function to check if a path is a root path.
-        fn is_root(path: &Path) -> bool {
-            path.parent().is_none()
-        }
-
-        // Helper function to check if a path has trailing slashes.
-        fn has_trailing_slash(path: &Path) -> bool {
-            nu_path::components(path).last()
-                == Some(std::path::Component::Normal(std::ffi::OsStr::new("")))
         }
 
         // Retrieve $env.PWD from the stack or the engine state.
         let pwd = if let Some(stack) = stack {
             stack.get_env_var(self, "PWD")
         } else {
-            self.get_env_var("PWD").map(ToOwned::to_owned)
+            self.get_env_var("PWD").cloned()
         };
 
-        if let Some(pwd) = pwd {
+        let pwd = pwd.ok_or_else(|| error("$env.PWD not found", ""))?;
+
         if let Value::String { val, .. } = pwd {
-                let path = PathBuf::from(val);
+            let path = AbsolutePathBuf::try_from(val)
+                .map_err(|path| error("$env.PWD is not an absolute path", path))?;
 
             // Technically, a root path counts as "having trailing slashes", but
             // for the purpose of PWD, a root path is acceptable.
-                if !is_root(&path) && has_trailing_slash(&path) {
-                    error("$env.PWD contains trailing slashes", path)
-                } else if !path.is_absolute() {
-                    error("$env.PWD is not an absolute path", path)
+            if path.parent().is_some() && nu_path::has_trailing_slash(path.as_ref()) {
+                Err(error("$env.PWD contains trailing slashes", &path))
             } else if !path.exists() {
-                    error("$env.PWD points to a non-existent directory", path)
+                Err(error("$env.PWD points to a non-existent directory", &path))
             } else if !path.is_dir() {
-                    error("$env.PWD points to a non-directory", path)
+                Err(error("$env.PWD points to a non-directory", &path))
             } else {
                 Ok(path)
             }
         } else {
-                error("$env.PWD is not a string", format!("{pwd:?}"))
-            }
-        } else {
-            error("$env.PWD not found", "")
+            Err(error("$env.PWD is not a string", format!("{pwd:?}")))
         }
     }