From 505653456d09858fe6ea69444d18163f126689df Mon Sep 17 00:00:00 2001
From: Charlie Marsh <charlie.r.marsh@gmail.com>
Date: Fri, 23 Feb 2024 14:47:58 -0500
Subject: [PATCH] Add compatibility for deprecated `python_implementation`
 marker (#1933)
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## Summary

Like `platform.python_implementation`, we should support the
`python_implementation` "alias" for `platform_python_implementation`.

Closes https://github.com/astral-sh/uv/issues/1906.

## Test Plan

```shell
❯ cargo run pip install "pynacl==1.4.0"
    Finished dev [unoptimized + debuginfo] target(s) in 7.02s
     Running `target/debug/uv pip install pynacl==1.4.0`
Resolved 4 packages in 9ms
   Built pynacl==1.4.0                                                                                                                                                                                                                        Downloaded 1 package in 31.51s
Installed 4 packages in 3ms
 + cffi==1.16.0
 + pycparser==2.21
 + pynacl==1.4.0
 + six==1.16.0
```
---
 crates/pep508-rs/src/marker.rs | 23 +++++++++++++++++++----
 1 file changed, 19 insertions(+), 4 deletions(-)

diff --git a/crates/pep508-rs/src/marker.rs b/crates/pep508-rs/src/marker.rs
index 7b09d0aa1..f10b690c7 100644
--- a/crates/pep508-rs/src/marker.rs
+++ b/crates/pep508-rs/src/marker.rs
@@ -96,6 +96,8 @@ pub enum MarkerValueString {
     PlatformPythonImplementation,
     /// Deprecated `platform.python_implementation` from <https://peps.python.org/pep-0345/#environment-markers>
     PlatformPythonImplementationDeprecated,
+    /// Deprecated `python_implementation` from <https://github.com/pypa/packaging/issues/72>
+    PythonImplementationDeprecated,
     /// `platform_release`
     PlatformRelease,
     /// `platform_system`
@@ -119,9 +121,9 @@ impl Display for MarkerValueString {
             Self::PlatformMachine | Self::PlatformMachineDeprecated => {
                 f.write_str("platform_machine")
             }
-            Self::PlatformPythonImplementation | Self::PlatformPythonImplementationDeprecated => {
-                f.write_str("platform_python_implementation")
-            }
+            Self::PlatformPythonImplementation
+            | Self::PlatformPythonImplementationDeprecated
+            | Self::PythonImplementationDeprecated => f.write_str("platform_python_implementation"),
             Self::PlatformRelease => f.write_str("platform_release"),
             Self::PlatformSystem => f.write_str("platform_system"),
             Self::PlatformVersion | Self::PlatformVersionDeprecated => {
@@ -175,6 +177,9 @@ impl FromStr for MarkerValue {
             "platform.python_implementation" => {
                 Self::MarkerEnvString(MarkerValueString::PlatformPythonImplementationDeprecated)
             }
+            "python_implementation" => {
+                Self::MarkerEnvString(MarkerValueString::PythonImplementationDeprecated)
+            }
             "platform_release" => Self::MarkerEnvString(MarkerValueString::PlatformRelease),
             "platform_system" => Self::MarkerEnvString(MarkerValueString::PlatformSystem),
             "platform_version" => Self::MarkerEnvString(MarkerValueString::PlatformVersion),
@@ -389,7 +394,8 @@ impl MarkerEnvironment {
                 &self.platform_machine
             }
             MarkerValueString::PlatformPythonImplementation
-            | MarkerValueString::PlatformPythonImplementationDeprecated => {
+            | MarkerValueString::PlatformPythonImplementationDeprecated
+            | MarkerValueString::PythonImplementationDeprecated => {
                 &self.platform_python_implementation
             }
             MarkerValueString::PlatformRelease => &self.platform_release,
@@ -1067,6 +1073,15 @@ impl MarkerTree {
                                 expression,
                             );
                         }
+                        MarkerValue::MarkerEnvString(
+                            MarkerValueString::PythonImplementationDeprecated,
+                        ) => {
+                            reporter(
+                                MarkerWarningKind::DeprecatedMarkerName,
+                                "python_implementation is deprecated in favor of platform_python_implementation".to_string(),
+                                expression,
+                            );
+                        }
                         MarkerValue::MarkerEnvString(
                             MarkerValueString::PlatformVersionDeprecated,
                         ) => {