Fix interpreter discovery for Windows.

CHANGES.md

@@ -1,5 +1,14 @@
 # Release Notes
 
+## 0.16.0
+
+This release fixes interpreter discovery for Windows. The [PEP-514 spec](
+https://peps.python.org/pep-0514/) is now implemented while also searching further on the 
+`PEX_PYTHON_PATH` or `PATH` as appropriate.
+
+In addition, the new `pexrc python {list,inspect}` tools allow insight into the `pexrc` interpreter
+discovery mechanism.
+
 ## 0.15.0
 
 This release adds defaults for Linux and Windows for the `platform_release` environment marker when

Cargo.toml

@@ -5,7 +5,7 @@ cargo-features = ["profile-rustflags"]
 
 [package]
 name = "pexrc"
-version = "0.15.0"
+version = "0.16.0"
 edition = { workspace = true }
 publish = false
 
@@ -210,6 +210,7 @@ url = "2.5"
 # does not have a feature to activate the dep.
 version-ranges = "*"
 walkdir = "2.5"
+windows-registry = "0.6"
 which = "8.0"
 xz2 = "0.1"
 zip = { version = "8.6", default-features = false, features = ["chrono", "deflate", "zstd"] }
@@ -253,6 +254,7 @@ python-proxy = { path = "crates/python-proxy" }
 rayon = { workspace = true }
 request = { path = "crates/request" }
 scripts = { path = "crates/scripts", features = ["embedded"] }
+serde_json = { workspace = true }
 sha2 = { workspace = true }
 strum = { workspace = true }
 target = { path = "crates/target" }

crates/boot/src/lib.rs

@@ -18,6 +18,7 @@ use interpreter::{
     SearchPath,
     SelectionStrategy,
     VersionSpec,
+    calculate_compatible_unix_binary_names,
 };
 use itertools::Itertools;
 use pex::{Pex, PexPath};
@@ -63,16 +64,20 @@ pub fn sh_boot_shebang(
         .interpreter_selection_strategy
         .unwrap_or(pex::InterpreterSelectionStrategy::Oldest)
         .into();
-    let pythons = interpreter_constraints
-        .calculate_compatible_binary_names(selection_strategy, preferred_interpreter)
-        .into_iter()
-        .map(|(binary_name, version_spec)| {
-            binary_name
-                .into_string()
-                .map(|binary_name| (binary_name, version_spec))
-                .map_err(|err| anyhow!("{err}", err = err.display()))
-        })
-        .collect::<anyhow::Result<Vec<_>>>()?;
+    let pythons = calculate_compatible_unix_binary_names(
+        &interpreter_constraints,
+        selection_strategy,
+        preferred_interpreter,
+        true,
+    )
+    .into_iter()
+    .map(|(binary_name, version_spec)| {
+        binary_name
+            .into_string()
+            .map(|binary_name| (binary_name, version_spec))
+            .map_err(|err| anyhow!("{err}", err = err.display()))
+    })
+    .collect::<anyhow::Result<Vec<_>>>()?;
     let python_args = if hermetic {
         if pythons.iter().any(|(_, version_spec)| {
             matches!(version_spec, None | Some(VersionSpec::Major(_)))

crates/build-system/src/tools.rs

@@ -21,7 +21,7 @@ use crate::downloads::ensure_download;
 use crate::metadata::{Build, CargoBinstall, Download, Embeds, Glibc};
 
 pub(crate) struct ToolBox<'a> {
-    emeds: Embeds<'a>,
+    embeds: Embeds<'a>,
     binstall: CargoBinstall<'a>,
     zig_version: &'a str,
     glibc: Glibc<'a>,
@@ -40,7 +40,7 @@ impl<'a> From<Build<'a>> for ToolBox<'a> {
         let downloads: Vec<(&'static str, Download<'a>)> = Vec::new();
 
         Self {
-            emeds: build.embeds,
+            embeds: build.embeds,
             binstall: build.cargo_binstall,
             zig_version: build.zig_version,
             glibc: build.glibc,
@@ -77,7 +77,7 @@ impl<'a> ToolBox<'a> {
             }
         }
         Ok(ToolInventory {
-            embeds: self.emeds,
+            embeds: self.embeds,
             binstall: self.binstall,
             downloads: self.downloads,
             zig,

crates/cli/src/json.rs

@@ -10,7 +10,7 @@ use serde_json::ser::PrettyFormatter;
 #[derive(Args)]
 pub struct Json {
     /// Pretty-print json output with the given indent.
-    #[arg(short = 'i', long)]
+    #[arg(short = 'i', long, help_heading = "Output")]
     indent: Option<u8>,
 }
 

crates/cli/src/output.rs

@@ -12,7 +12,7 @@ use fs_err::File;
 #[derive(Args)]
 pub struct Output {
     /// A file to send output to; STDOUT by default.
-    #[arg(short = 'o', long)]
+    #[arg(short = 'o', long, help_heading = "Output")]
     output: Option<PathBuf>,
 }
 

crates/interpreter/Cargo.toml

@@ -28,6 +28,9 @@ time = { workspace = true }
 url = { workspace = true }
 which = { workspace = true }
 
+[target.'cfg(windows)'.dependencies]
+windows-registry = { workspace = true }
+
 [dev-dependencies]
 anyhow = { workspace = true }
 pep440_rs = { workspace = true }