Introduce PreviewFeature to clarify intent throughout the codebase

Cargo.toml

@@ -110,6 +110,7 @@ dunce = { version = "1.0.5" }
 either = { version = "1.13.0" }
 encoding_rs_io = { version = "0.1.7" }
 embed-manifest = { version = "1.5.0" }
+enumflags2 = { version = "0.7.12" }
 etcetera = { version = "0.11.0" }
 fastrand = { version = "2.3.0" }
 flate2 = { version = "1.0.33", default-features = false, features = ["zlib-rs"] }

crates/uv-auth/src/middleware.rs

@@ -8,7 +8,7 @@ use reqwest_middleware::{ClientWithMiddleware, Error, Middleware, Next};
 use tokio::sync::Mutex;
 use tracing::{debug, trace, warn};
 
-use uv_preview::{Preview, PreviewFeatures};
+use uv_preview::{Preview, PreviewFeature};
 use uv_redacted::DisplaySafeUrl;
 use uv_static::EnvVars;
 use uv_warnings::owo_colors::OwoColorize;
@@ -815,7 +815,7 @@ impl AuthMiddleware {
             debug!("Found credentials in plaintext store for {url}");
             Some(credentials)
         } else if let Some(credentials) = {
-            if self.preview.is_enabled(PreviewFeatures::NATIVE_AUTH) {
+            if self.preview.is_enabled(PreviewFeature::NativeAuth) {
                 let native_store = KeyringProvider::native();
                 let username = credentials.and_then(|credentials| credentials.username());
                 let display_username = if let Some(username) = username {

crates/uv-auth/src/providers.rs

@@ -6,7 +6,7 @@ use reqsign::google::DefaultSigner as GcsDefaultSigner;
 use tracing::debug;
 use url::Url;
 
-use uv_preview::{Preview, PreviewFeatures};
+use uv_preview::{Preview, PreviewFeature};
 use uv_static::EnvVars;
 use uv_warnings::warn_user_once;
 
@@ -70,10 +70,10 @@ impl S3EndpointProvider {
     /// Returns `true` if the URL matches the configured S3 endpoint.
     pub(crate) fn is_s3_endpoint(url: &Url, preview: Preview) -> bool {
         if let Some(s3_endpoint_realm) = S3_ENDPOINT_REALM.as_ref().map(RealmRef::from) {
-            if !preview.is_enabled(PreviewFeatures::S3_ENDPOINT) {
+            if !preview.is_enabled(PreviewFeature::S3Endpoint) {
                 warn_user_once!(
                     "The `s3-endpoint` option is experimental and may change without warning. Pass `--preview-features {}` to disable this warning.",
-                    PreviewFeatures::S3_ENDPOINT
+                    PreviewFeature::S3Endpoint
                 );
             }
 
@@ -119,10 +119,10 @@ impl GcsEndpointProvider {
     /// Returns `true` if the URL matches the configured GCS endpoint.
     pub(crate) fn is_gcs_endpoint(url: &Url, preview: Preview) -> bool {
         if let Some(gcs_endpoint_realm) = GCS_ENDPOINT_REALM.as_ref().map(RealmRef::from) {
-            if !preview.is_enabled(PreviewFeatures::GCS_ENDPOINT) {
+            if !preview.is_enabled(PreviewFeature::GcsEndpoint) {
                 warn_user_once!(
                     "The `gcs-endpoint` option is experimental and may change without warning. Pass `--preview-features {}` to disable this warning.",
-                    PreviewFeatures::GCS_ENDPOINT
+                    PreviewFeature::GcsEndpoint
                 );
             }
 

crates/uv-auth/src/store.rs

@@ -6,7 +6,7 @@ use rustc_hash::FxHashMap;
 use serde::{Deserialize, Serialize};
 use thiserror::Error;
 use uv_fs::{LockedFile, LockedFileError, LockedFileMode, with_added_extension};
-use uv_preview::{Preview, PreviewFeatures};
+use uv_preview::{Preview, PreviewFeature};
 use uv_redacted::DisplaySafeUrl;
 
 use uv_state::{StateBucket, StateStore};
@@ -30,7 +30,7 @@ pub enum AuthBackend {
 impl AuthBackend {
     pub async fn from_settings(preview: Preview) -> Result<Self, TomlCredentialError> {
         // If preview is enabled, we'll use the system-native store
-        if preview.is_enabled(PreviewFeatures::NATIVE_AUTH) {
+        if preview.is_enabled(PreviewFeature::NativeAuth) {
             return Ok(Self::System(KeyringProvider::native()));
         }
 

crates/uv-build-backend/src/lib.rs

@@ -453,7 +453,7 @@ mod tests {
     use tempfile::TempDir;
     use uv_distribution_filename::{SourceDistFilename, WheelFilename};
     use uv_fs::{copy_dir_all, relative_to};
-    use uv_preview::{Preview, PreviewFeatures};
+    use uv_preview::{Preview, PreviewFeature};
 
     const MOCK_UV_VERSION: &str = "1.0.0+test";
 
@@ -1810,7 +1810,7 @@ mod tests {
         let build = build(
             src.path(),
             dist.path(),
-            Preview::new(PreviewFeatures::METADATA_JSON),
+            Preview::new(&[PreviewFeature::MetadataJson]),
         )
         .unwrap();
 

crates/uv-build-backend/src/wheel.rs

@@ -16,7 +16,7 @@ use uv_distribution_filename::WheelFilename;
 use uv_fs::Simplified;
 use uv_globfilter::{GlobDirFilter, PortableGlobParser};
 use uv_platform_tags::{AbiTag, LanguageTag, PlatformTag};
-use uv_preview::{Preview, PreviewFeatures};
+use uv_preview::{Preview, PreviewFeature};
 use uv_warnings::warn_user_once;
 
 use crate::metadata::DEFAULT_EXCLUDES;
@@ -611,7 +611,7 @@ fn write_dist_info(
         &format!("{dist_info_dir}/WHEEL"),
         wheel_info.to_string().as_bytes(),
     )?;
-    if preview.is_enabled(PreviewFeatures::METADATA_JSON) {
+    if preview.is_enabled(PreviewFeature::MetadataJson) {
         writer.write_bytes(
             &format!("{dist_info_dir}/WHEEL.json"),
             &serde_json::to_vec(&wheel_info).map_err(Error::Json)?,
@@ -632,7 +632,7 @@ fn write_dist_info(
         &format!("{dist_info_dir}/METADATA"),
         metadata.core_metadata_format().as_bytes(),
     )?;
-    if preview.is_enabled(PreviewFeatures::METADATA_JSON) {
+    if preview.is_enabled(PreviewFeature::MetadataJson) {
         writer.write_bytes(
             &format!("{dist_info_dir}/METADATA.json"),
             &serde_json::to_vec(&metadata).map_err(Error::Json)?,

crates/uv-build/src/main.rs

@@ -2,7 +2,7 @@ use std::env;
 use std::io::Write;
 use std::path::PathBuf;
 use std::str::FromStr;
-use uv_preview::{Preview, PreviewFeatures};
+use uv_preview::Preview;
 use uv_static::{EnvVars, parse_boolish_environment_variable};
 
 use anyhow::{Context, Result, bail};
@@ -42,23 +42,21 @@ fn main() -> Result<()> {
         .to_string();
 
     // Ad-hoc preview features parsing due to a lack of clap CLI in uv-build.
-    let preview_features =
-        if parse_boolish_environment_variable(EnvVars::UV_PREVIEW)?.unwrap_or(false) {
-            PreviewFeatures::all()
-        } else if let Some(preview_features) = env::var_os(EnvVars::UV_PREVIEW_FEATURES) {
-            let preview_features = preview_features
-                .to_str()
-                .with_context(|| format!("Invalid UTF-8 in `{}`", EnvVars::UV_PREVIEW_FEATURES))?;
-            PreviewFeatures::from_str(preview_features).with_context(|| {
-                format!(
-                    "Invalid preview features list in `{}`",
-                    EnvVars::UV_PREVIEW_FEATURES
-                )
-            })?
-        } else {
-            PreviewFeatures::default()
-        };
-    let preview = Preview::new(preview_features);
+    let preview = if parse_boolish_environment_variable(EnvVars::UV_PREVIEW)?.unwrap_or(false) {
+        Preview::all()
+    } else if let Some(preview_features) = env::var_os(EnvVars::UV_PREVIEW_FEATURES) {
+        let preview_features = preview_features
+            .to_str()
+            .with_context(|| format!("Invalid UTF-8 in `{}`", EnvVars::UV_PREVIEW_FEATURES))?;
+        Preview::from_str(preview_features).with_context(|| {
+            format!(
+                "Invalid preview features list in `{}`",
+                EnvVars::UV_PREVIEW_FEATURES
+            )
+        })?
+    } else {
+        Preview::default()
+    };
     match command.as_str() {
         "build-sdist" => {
             let sdist_directory = PathBuf::from(args.next().context("Missing sdist directory")?);

crates/uv-cli/src/lib.rs

@@ -23,7 +23,7 @@ use uv_distribution_types::{
 };
 use uv_normalize::{ExtraName, GroupName, PackageName, PipGroupName};
 use uv_pep508::{MarkerTree, Requirement};
-use uv_preview::PreviewFeatures;
+use uv_preview::PreviewFeature;
 use uv_pypi_types::VerbatimParsedUrl;
 use uv_python::{PythonDownloads, PythonPreference, PythonVersion};
 use uv_redacted::DisplaySafeUrl;
@@ -306,7 +306,7 @@ pub struct GlobalArgs {
         alias = "preview-feature",
         value_enum,
     )]
-    pub preview_features: Vec<PreviewFeatures>,
+    pub preview_features: Vec<PreviewFeature>,
 
     /// Avoid discovering a `pyproject.toml` or `uv.toml` file [env: UV_ISOLATED=]
     ///

crates/uv-install-wheel/src/linker.rs

@@ -16,7 +16,7 @@ use walkdir::WalkDir;
 
 use uv_distribution_filename::WheelFilename;
 use uv_fs::Simplified;
-use uv_preview::{Preview, PreviewFeatures};
+use uv_preview::{Preview, PreviewFeature};
 use uv_warnings::{warn_user, warn_user_once};
 
 use crate::Error;
@@ -104,7 +104,7 @@ impl Locks {
         // This warning is currently in preview.
         if !self
             .preview
-            .is_enabled(PreviewFeatures::DETECT_MODULE_CONFLICTS)
+            .is_enabled(PreviewFeature::DetectModuleConflicts)
         {
             return Ok(());
         }

crates/uv-preview/Cargo.toml

@@ -18,7 +18,8 @@ workspace = true
 [dependencies]
 uv-warnings = { workspace = true }
 
-bitflags = { workspace = true }
+enumflags2 = { workspace = true }
+itertools = { workspace = true }
 thiserror = { workspace = true }
 
 [dev-dependencies]