Move `TRACING_DURATIONS_FILE` to `EnvironmentOptions` (#16109)

<!--
Thank you for contributing to uv! To help us out with reviewing, please
consider the following:

- Does this pull request include a summary of the change? (See below.)
- Does this pull request include a descriptive title?
- Does this pull request include references to any relevant issues?
-->

## Summary

<!-- What's the purpose of the change? What does it do, and why? -->

Fixes a part of #14720

Add `TRACING_DURATIONS_FILE` to EnvironmentOptions.

## Test Plan

<!-- How was it tested? -->

crates/uv-settings/Cargo.toml

@@ -50,3 +50,6 @@ url = { workspace = true }
 ignored = ["uv-options-metadata", "clap"]
 
 [dev-dependencies]
+
+[features]
+tracing-durations-export = []

crates/uv-settings/src/lib.rs

@@ -574,6 +574,8 @@ pub struct EnvironmentOptions {
     pub python_install_registry: Option<bool>,
     pub install_mirrors: PythonInstallMirrors,
     pub log_context: Option<bool>,
+    #[cfg(feature = "tracing-durations-export")]
+    pub tracing_durations_file: Option<PathBuf>,
 }
 
 impl EnvironmentOptions {
@@ -599,6 +601,10 @@ impl EnvironmentOptions {
                 )?,
             },
             log_context: parse_boolish_environment_variable(EnvVars::UV_LOG_CONTEXT)?,
+            #[cfg(feature = "tracing-durations-export")]
+            tracing_durations_file: parse_path_environment_variable(
+                EnvVars::TRACING_DURATIONS_FILE,
+            ),
         })
     }
 }
@@ -676,6 +682,18 @@ fn parse_string_environment_variable(name: &'static str) -> Result<Option<String
     }
 }
 
+#[cfg(feature = "tracing-durations-export")]
+/// Parse a path environment variable.
+fn parse_path_environment_variable(name: &'static str) -> Option<PathBuf> {
+    let value = std::env::var_os(name)?;
+
+    if value.is_empty() {
+        return None;
+    }
+
+    Some(PathBuf::from(value))
+}
+
 /// Populate the [`EnvironmentFlags`] from the given [`EnvironmentOptions`].
 impl From<&EnvironmentOptions> for EnvironmentFlags {
     fn from(options: &EnvironmentOptions) -> Self {

crates/uv/Cargo.toml

@@ -167,7 +167,7 @@ performance-memory-allocator = ["dep:uv-performance-memory-allocator"]
 self-update = ["axoupdater", "uv-cli/self-update"]
 
 # Features for development only.
-tracing-durations-export = ["dep:tracing-durations-export", "uv-resolver/tracing-durations-export"]
+tracing-durations-export = ["dep:tracing-durations-export", "uv-resolver/tracing-durations-export", "uv-settings/tracing-durations-export"]
 
 # Features that only apply when running tests, no-ops otherwise.
 default-tests = [

crates/uv/src/lib.rs

@@ -360,7 +360,8 @@ async fn run(mut cli: Cli) -> Result<ExitStatus> {
 
     // Configure the `tracing` crate, which controls internal logging.
     #[cfg(feature = "tracing-durations-export")]
-    let (durations_layer, _duration_guard) = logging::setup_durations()?;
+    let (durations_layer, _duration_guard) =
+        logging::setup_durations(environment.tracing_durations_file.as_ref())?;
     #[cfg(not(feature = "tracing-durations-export"))]
     let durations_layer = None::<tracing_subscriber::layer::Identity>;
     logging::setup_logging(

crates/uv/src/logging.rs

@@ -14,8 +14,6 @@ use tracing_tree::time::Uptime;
 
 use uv_cli::ColorChoice;
 use uv_logging::UvFormat;
-#[cfg(feature = "tracing-durations-export")]
-use uv_static::EnvVars;
 
 #[derive(Debug, Default, Clone, Copy, PartialEq, Eq)]
 pub(crate) enum Level {
@@ -120,12 +118,13 @@ pub(crate) fn setup_logging(
 
 /// Setup the `TRACING_DURATIONS_FILE` environment variable to enable tracing durations.
 #[cfg(feature = "tracing-durations-export")]
-pub(crate) fn setup_durations() -> anyhow::Result<(
+pub(crate) fn setup_durations(
+    tracing_durations_file: Option<&std::path::PathBuf>,
+) -> anyhow::Result<(
     Option<DurationsLayer<Registry>>,
     Option<DurationsLayerDropGuard>,
 )> {
-    if let Ok(location) = std::env::var(EnvVars::TRACING_DURATIONS_FILE) {
-        let location = std::path::PathBuf::from(location);
+    if let Some(location) = tracing_durations_file {
         if let Some(parent) = location.parent() {
             fs_err::create_dir_all(parent)
                 .context("Failed to create parent of TRACING_DURATIONS_FILE")?;
@@ -141,7 +140,7 @@ pub(crate) fn setup_durations() -> anyhow::Result<(
             ..PlotConfig::default()
         };
         let (layer, guard) = DurationsLayerBuilder::default()
-            .durations_file(&location)
+            .durations_file(location)
             .plot_file(location.with_extension("svg"))
             .plot_config(plot_config)
             .build()