Replace println with Printer for all dir commands & workspace dir followups (#16690)

## Summary

1. Discussed in review of #16678 that println should be replaced by
using `printer`. The `println` pattern was pretty consistent across all
the `dir` commands, so I've updated all of them in this PR (there are
some usages of `println` outside of `uv/src/commands` that I didn't
touch -- the use cases there seemed more complex and nuanced).
2. I missed two comments in the previous PR before merging, so updates
from those are in here as well.

## Test Plan

No behavior changes, existing tests for all commands pass.

---------

Signed-off-by: Mikayla Thompson <mrt@mikayla.codes>

crates/uv/src/commands/auth/dir.rs

@@ -1,20 +1,26 @@
-use anstream::println;
 use owo_colors::OwoColorize;
+use std::fmt::Write;
 
 use uv_auth::{PyxTokenStore, Service, TextCredentialStore};
 use uv_fs::Simplified;
 
+use crate::printer::Printer;
+
 /// Show the credentials directory.
-pub(crate) fn dir(service: Option<&Service>) -> anyhow::Result<()> {
+pub(crate) fn dir(service: Option<&Service>, printer: Printer) -> anyhow::Result<()> {
     if let Some(service) = service {
         let pyx_store = PyxTokenStore::from_settings()?;
         if pyx_store.is_known_domain(service.url()) {
-            println!("{}", pyx_store.root().simplified_display().cyan());
+            writeln!(
+                printer.stdout(),
+                "{}",
+                pyx_store.root().simplified_display().cyan()
+            )?;
             return Ok(());
         }
     }
 
     let root = TextCredentialStore::directory_path()?;
-    println!("{}", root.simplified_display().cyan());
+    writeln!(printer.stdout(), "{}", root.simplified_display().cyan())?;
     Ok(())
 }

crates/uv/src/commands/cache_dir.rs

@@ -1,10 +1,18 @@
-use anstream::println;
 use owo_colors::OwoColorize;
+use std::fmt::Write;
 
 use uv_cache::Cache;
 use uv_fs::Simplified;
 
+use crate::commands::ExitStatus;
+use crate::printer::Printer;
+
 /// Show the cache directory.
-pub(crate) fn cache_dir(cache: &Cache) {
-    println!("{}", cache.root().simplified_display().cyan());
+pub(crate) fn cache_dir(cache: &Cache, printer: Printer) -> anyhow::Result<ExitStatus> {
+    writeln!(
+        printer.stdout(),
+        "{}",
+        cache.root().simplified_display().cyan()
+    )?;
+    Ok(ExitStatus::Success)
 }

crates/uv/src/commands/python/dir.rs

@@ -1,22 +1,26 @@
-use anstream::println;
+use std::fmt::Write;
+
 use anyhow::Context;
 use owo_colors::OwoColorize;
 
 use uv_fs::Simplified;
 use uv_python::managed::{ManagedPythonInstallations, python_executable_dir};
 
+use crate::printer::Printer;
+
 /// Show the Python installation directory.
-pub(crate) fn dir(bin: bool) -> anyhow::Result<()> {
+pub(crate) fn dir(bin: bool, printer: Printer) -> anyhow::Result<()> {
     if bin {
         let bin = python_executable_dir()?;
-        println!("{}", bin.simplified_display().cyan());
+        writeln!(printer.stdout(), "{}", bin.simplified_display().cyan())?;
     } else {
         let installed_toolchains = ManagedPythonInstallations::from_settings(None)
             .context("Failed to initialize toolchain settings")?;
-        println!(
+        writeln!(
+            printer.stdout(),
             "{}",
             installed_toolchains.root().simplified_display().cyan()
-        );
+        )?;
     }
 
     Ok(())

crates/uv/src/commands/tool/dir.rs

@@ -1,4 +1,5 @@
-use anstream::println;
+use std::fmt::Write;
+
 use anyhow::Context;
 use owo_colors::OwoColorize;
 
@@ -6,15 +7,25 @@ use uv_fs::Simplified;
 use uv_preview::Preview;
 use uv_tool::{InstalledTools, tool_executable_dir};
 
+use crate::printer::Printer;
+
 /// Show the tool directory.
-pub(crate) fn dir(bin: bool, _preview: Preview) -> anyhow::Result<()> {
+pub(crate) fn dir(bin: bool, _preview: Preview, printer: Printer) -> anyhow::Result<()> {
     if bin {
         let executable_directory = tool_executable_dir()?;
-        println!("{}", executable_directory.simplified_display().cyan());
+        writeln!(
+            printer.stdout(),
+            "{}",
+            executable_directory.simplified_display().cyan()
+        )?;
     } else {
         let installed_tools =
             InstalledTools::from_settings().context("Failed to initialize tools settings")?;
-        println!("{}", installed_tools.root().simplified_display().cyan());
+        writeln!(
+            printer.stdout(),
+            "{}",
+            installed_tools.root().simplified_display().cyan()
+        )?;
     }
 
     Ok(())

crates/uv/src/commands/workspace/dir.rs

@@ -31,11 +31,11 @@ pub(crate) async fn dir(
     let workspace =
         Workspace::discover(project_dir, &DiscoveryOptions::default(), &workspace_cache).await?;
 
-    let dir: &Path = match package_name {
-        None => workspace.install_path().as_path(),
+    let dir = match package_name {
+        None => workspace.install_path(),
         Some(package) => {
             if let Some(p) = workspace.packages().get(&package) {
-                p.root().as_path()
+                p.root()
             } else {
                 bail!("Package `{package}` not found in workspace.")
             }

crates/uv/src/lib.rs

@@ -531,7 +531,7 @@ async fn run(mut cli: Cli) -> Result<ExitStatus> {
         Commands::Auth(AuthNamespace {
             command: AuthCommand::Dir(args),
         }) => {
-            commands::auth_dir(args.service.as_ref())?;
+            commands::auth_dir(args.service.as_ref(), printer)?;
             Ok(ExitStatus::Success)
         }
         Commands::Help(args) => commands::help(
@@ -1056,10 +1056,7 @@ async fn run(mut cli: Cli) -> Result<ExitStatus> {
         }
         Commands::Cache(CacheNamespace {
             command: CacheCommand::Dir,
-        }) => {
-            commands::cache_dir(&cache);
-            Ok(ExitStatus::Success)
-        }
+        }) => commands::cache_dir(&cache, printer),
         Commands::Cache(CacheNamespace {
             command: CacheCommand::Size(args),
         }) => commands::cache_size(&cache, args.human, printer, globals.preview),
@@ -1504,7 +1501,7 @@ async fn run(mut cli: Cli) -> Result<ExitStatus> {
             let args = settings::ToolDirSettings::resolve(args, filesystem);
             show_settings!(args);
 
-            commands::tool_dir(args.bin, globals.preview)?;
+            commands::tool_dir(args.bin, globals.preview, printer)?;
             Ok(ExitStatus::Success)
         }
         Commands::Python(PythonNamespace {
@@ -1680,7 +1677,7 @@ async fn run(mut cli: Cli) -> Result<ExitStatus> {
             let args = settings::PythonDirSettings::resolve(args, filesystem);
             show_settings!(args);
 
-            commands::python_dir(args.bin)?;
+            commands::python_dir(args.bin, printer)?;
             Ok(ExitStatus::Success)
         }
         Commands::Python(PythonNamespace {

crates/uv/tests/it/workspace_dir.rs

@@ -27,7 +27,7 @@ fn workspace_dir_simple() {
     );
 }
 
-// Workspace dir output when run with `--package`
+/// Workspace dir output when run with `--package`.
 #[test]
 fn workspace_dir_specific_package() {
     let context = TestContext::new("3.12");