Add InterpreterRequest::Any instead of using VersionRequest::Any (#3789)

A follow-up to #3266 addressing some awkwardness where there was no
"empty" or default interpreter request kind.

crates/uv-interpreter/src/discovery.rs

@@ -26,8 +26,11 @@ use std::{path::Path, path::PathBuf, str::FromStr};
 /// A request to find a Python interpreter.
 ///
 /// See [`InterpreterRequest::from_str`].
-#[derive(Debug, Clone, PartialEq, Eq)]
+#[derive(Debug, Clone, PartialEq, Eq, Default)]
 pub enum InterpreterRequest {
+    /// Use any discovered Python interpreter
+    #[default]
+    Any,
     /// A Python version without an implementation name e.g. `3.10`
     Version(VersionRequest),
     /// A path to a directory containing a Python installation, e.g. `.venv`
@@ -60,7 +63,7 @@ pub enum SourceSelector {
 #[derive(Copy, Clone, Debug, Default, PartialEq, Eq)]
 pub enum VersionRequest {
     #[default]
-    Default,
+    Any,
     Major(u8),
     MajorMinor(u8, u8),
     MajorMinorPatch(u8, u8, u8),
@@ -297,7 +300,7 @@ fn python_executables_from_search_path<'a>(
         env::var_os("UV_TEST_PYTHON_PATH").unwrap_or(env::var_os("PATH").unwrap_or_default());
 
     let possible_names: Vec<_> = version
-        .unwrap_or(&VersionRequest::Default)
+        .unwrap_or(&VersionRequest::Any)
         .possible_names(implementation)
         .collect();
 
@@ -565,6 +568,27 @@ pub fn find_interpreter(
                 interpreter,
             }
         }
+        InterpreterRequest::Any => {
+            let Some((source, interpreter)) =
+                python_interpreters(None, None, system, sources, cache)
+                    .find(|result| {
+                        match result {
+                            // Return the first critical error or interpreter
+                            Err(err) => should_stop_discovery(err),
+                            Ok(_) => true,
+                        }
+                    })
+                    .transpose()?
+            else {
+                return Ok(InterpreterResult::Err(
+                    InterpreterNotFound::NoPythonInstallation(sources.clone(), None),
+                ));
+            };
+            DiscoveredInterpreter {
+                source,
+                interpreter,
+            }
+        }
         InterpreterRequest::Version(version) => {
             let Some((source, interpreter)) =
                 python_interpreters(Some(version), None, system, sources, cache)
@@ -577,7 +601,7 @@ pub fn find_interpreter(
                     })
                     .transpose()?
             else {
-                let err = if matches!(version, VersionRequest::Default) {
+                let err = if matches!(version, VersionRequest::Any) {
                     InterpreterNotFound::NoPythonInstallation(sources.clone(), Some(*version))
                 } else {
                     InterpreterNotFound::NoMatchingVersion(sources.clone(), *version)
@@ -600,7 +624,7 @@ pub fn find_interpreter(
 ///
 /// See [`find_interpreter`] for more details on interpreter discovery.
 pub fn find_default_interpreter(cache: &Cache) -> Result<InterpreterResult, Error> {
-    let request = InterpreterRequest::Version(VersionRequest::Default);
+    let request = InterpreterRequest::default();
     let sources = SourceSelector::System;
 
     let result = find_interpreter(&request, SystemPython::Required, &sources, cache)?;
@@ -665,7 +689,7 @@ pub fn find_best_interpreter(
 
     // If a Python version was requested but cannot be fulfilled, just take any version
     debug!("Looking for Python interpreter with any version");
-    let request = InterpreterRequest::Version(VersionRequest::Default);
+    let request = InterpreterRequest::Any;
     Ok(find_interpreter(
         // TODO(zanieb): Add a dedicated `Default` variant to `InterpreterRequest`
         &request, system, &sources, cache,
@@ -917,7 +941,7 @@ impl VersionRequest {
         };
 
         match self {
-            Self::Default => [Some(python3), Some(python), None, None],
+            Self::Any => [Some(python3), Some(python), None, None],
             Self::Major(major) => [
                 Some(Cow::Owned(format!("python{major}{extension}"))),
                 Some(python),
@@ -960,7 +984,7 @@ impl VersionRequest {
                 };
 
                 match self {
-                    Self::Default => [Some(python3), Some(python), None, None],
+                    Self::Any => [Some(python3), Some(python), None, None],
                     Self::Major(major) => [
                         Some(Cow::Owned(format!("{name}{major}{extension}"))),
                         Some(python),
@@ -990,7 +1014,7 @@ impl VersionRequest {
     /// Check if a interpreter matches the requested Python version.
     fn matches_interpreter(self, interpreter: &Interpreter) -> bool {
         match self {
-            Self::Default => true,
+            Self::Any => true,
             Self::Major(major) => interpreter.python_major() == major,
             Self::MajorMinor(major, minor) => {
                 (interpreter.python_major(), interpreter.python_minor()) == (major, minor)
@@ -1007,7 +1031,7 @@ impl VersionRequest {
 
     fn matches_version(self, version: &PythonVersion) -> bool {
         match self {
-            Self::Default => true,
+            Self::Any => true,
             Self::Major(major) => version.major() == major,
             Self::MajorMinor(major, minor) => (version.major(), version.minor()) == (major, minor),
             Self::MajorMinorPatch(major, minor, patch) => {
@@ -1018,7 +1042,7 @@ impl VersionRequest {
 
     fn matches_major_minor(self, major: u8, minor: u8) -> bool {
         match self {
-            Self::Default => true,
+            Self::Any => true,
             Self::Major(self_major) => self_major == major,
             Self::MajorMinor(self_major, self_minor) => (self_major, self_minor) == (major, minor),
             Self::MajorMinorPatch(self_major, self_minor, _) => {
@@ -1030,7 +1054,7 @@ impl VersionRequest {
     /// Return true if a patch version is present in the request.
     fn has_patch(self) -> bool {
         match self {
-            Self::Default => false,
+            Self::Any => false,
             Self::Major(..) => false,
             Self::MajorMinor(..) => false,
             Self::MajorMinorPatch(..) => true,
@@ -1041,7 +1065,7 @@ impl VersionRequest {
     #[must_use]
     fn without_patch(self) -> Self {
         match self {
-            Self::Default => Self::Default,
+            Self::Any => Self::Any,
             Self::Major(major) => Self::Major(major),
             Self::MajorMinor(major, minor) => Self::MajorMinor(major, minor),
             Self::MajorMinorPatch(major, minor, _) => Self::MajorMinor(major, minor),
@@ -1082,7 +1106,7 @@ impl From<&PythonVersion> for VersionRequest {
 impl fmt::Display for VersionRequest {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
         match self {
-            Self::Default => f.write_str("default"),
+            Self::Any => f.write_str("default"),
             Self::Major(major) => write!(f, "{major}"),
             Self::MajorMinor(major, minor) => write!(f, "{major}.{minor}"),
             Self::MajorMinorPatch(major, minor, patch) => {
@@ -1161,6 +1185,7 @@ impl SystemPython {
 impl fmt::Display for InterpreterRequest {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
         match self {
+            Self::Any => write!(f, "any Python"),
             Self::Version(version) => write!(f, "Python @ {version}"),
             Self::Directory(path) => write!(f, "directory {}", path.user_display()),
             Self::File(path) => write!(f, "file {}", path.user_display()),
@@ -1193,13 +1218,13 @@ impl fmt::Display for InterpreterSource {
 impl fmt::Display for InterpreterNotFound {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
         match self {
-            Self::NoPythonInstallation(sources, None | Some(VersionRequest::Default)) => {
+            Self::NoPythonInstallation(sources, None | Some(VersionRequest::Any)) => {
                 write!(f, "No Python interpreters found in {sources}")
             }
             Self::NoPythonInstallation(sources, Some(version)) => {
                 write!(f, "No Python {version} interpreters found in {sources}")
             }
-            Self::NoMatchingVersion(sources, VersionRequest::Default) => {
+            Self::NoMatchingVersion(sources, VersionRequest::Any) => {
                 write!(f, "No Python interpreter found in {sources}")
             }
             Self::NoMatchingVersion(sources, version) => {

crates/uv-interpreter/src/environment.rs

@@ -8,7 +8,7 @@ use same_file::is_same_file;
 use uv_cache::Cache;
 use uv_fs::{LockedFile, Simplified};
 
-use crate::discovery::{InterpreterRequest, SourceSelector, SystemPython, VersionRequest};
+use crate::discovery::{InterpreterRequest, SourceSelector, SystemPython};
 use crate::virtualenv::{virtualenv_python_executable, PyVenvConfiguration};
 use crate::{
     find_default_interpreter, find_interpreter, Error, Interpreter, InterpreterSource, Target,
@@ -54,7 +54,7 @@ impl PythonEnvironment {
     /// Allows Conda environments (via `CONDA_PREFIX`) though they are not technically virtual environments.
     pub fn from_virtualenv(cache: &Cache) -> Result<Self, Error> {
         let sources = SourceSelector::VirtualEnv;
-        let request = InterpreterRequest::Version(VersionRequest::Default);
+        let request = InterpreterRequest::Any;
         let found = find_interpreter(&request, SystemPython::Disallowed, &sources, cache)??;
 
         debug_assert!(
@@ -74,7 +74,7 @@ impl PythonEnvironment {
     /// Create a [`PythonEnvironment`] for the parent interpreter i.e. the executable in `python -m uv ...`
     pub fn from_parent_interpreter(system: SystemPython, cache: &Cache) -> Result<Self, Error> {
         let sources = SourceSelector::from_sources([InterpreterSource::ParentInterpreter]);
-        let request = InterpreterRequest::Version(VersionRequest::Default);
+        let request = InterpreterRequest::Any;
         let found = find_interpreter(&request, system, &sources, cache)??;
 
         Ok(Self(Arc::new(PythonEnvironmentShared {

crates/uv-interpreter/src/lib.rs

@@ -586,7 +586,7 @@ mod tests {
             ],
             || {
                 let result = find_interpreter(
-                    &InterpreterRequest::Version(VersionRequest::Default),
+                    &InterpreterRequest::Any,
                     SystemPython::Allowed,
                     &SourceSelector::All,
                     &cache,
@@ -620,7 +620,7 @@ mod tests {
             ],
             || {
                 let result = find_interpreter(
-                    &InterpreterRequest::Version(VersionRequest::Default),
+                    &InterpreterRequest::Any,
                     SystemPython::Allowed,
                     &SourceSelector::All,
                     &cache,
@@ -661,7 +661,7 @@ mod tests {
             ],
             || {
                 let result = find_interpreter(
-                    &InterpreterRequest::Version(VersionRequest::Default),
+                    &InterpreterRequest::Any,
                     SystemPython::Required,
                     &SourceSelector::All,
                     &cache,
@@ -701,7 +701,7 @@ mod tests {
             ],
             || {
                 let result = find_interpreter(
-                    &InterpreterRequest::Version(VersionRequest::Default),
+                    &InterpreterRequest::Any,
                     SystemPython::Disallowed,
                     &SourceSelector::All,
                     &cache,

crates/uv/src/commands/pip/compile.rs

@@ -178,7 +178,7 @@ pub(crate) async fn pip_compile(
             // TODO(zanieb): We should consolidate `VersionRequest` and `PythonVersion`
             InterpreterRequest::Version(VersionRequest::from(version))
         } else {
-            InterpreterRequest::Version(VersionRequest::Default)
+            InterpreterRequest::default()
         };
         find_best_interpreter(&request, system, &cache)??
     }