Treat deprecated aliases as equivalent in marker algebra (#9342)

## Summary

This PR modifies our lowered representation such that any deprecated
aliases are treated as "the same" marker in the algebra.

So, for example, we now recognize that this is impossible, despite the
marker names being different:

```
typing-extensions ; platform.python_implementation == 'CPython' and python_implementation != 'CPython'
```

Similarly, we now recognize that this is just `sys_platform == 'win32'`,
despite the presence of both markers:

```
anyio ; sys_platform == 'win32' and sys.platform == 'win32'
```

Author: charliermarsh

crates/uv-pep508/src/marker/environment.rs

@@ -47,22 +47,15 @@ impl MarkerEnvironment {
     pub fn get_string(&self, key: LoweredMarkerValueString) -> &str {
         match key {
             LoweredMarkerValueString::ImplementationName => self.implementation_name(),
-            LoweredMarkerValueString::OsName | LoweredMarkerValueString::OsNameDeprecated => {
-                self.os_name()
-            }
-            LoweredMarkerValueString::PlatformMachine
-            | LoweredMarkerValueString::PlatformMachineDeprecated => self.platform_machine(),
-            LoweredMarkerValueString::PlatformPythonImplementation
-            | LoweredMarkerValueString::PlatformPythonImplementationDeprecated
-            | LoweredMarkerValueString::PythonImplementationDeprecated => {
+            LoweredMarkerValueString::OsName => self.os_name(),
+            LoweredMarkerValueString::PlatformMachine => self.platform_machine(),
+            LoweredMarkerValueString::PlatformPythonImplementation => {
                 self.platform_python_implementation()
             }
             LoweredMarkerValueString::PlatformRelease => self.platform_release(),
             LoweredMarkerValueString::PlatformSystem => self.platform_system(),
-            LoweredMarkerValueString::PlatformVersion
-            | LoweredMarkerValueString::PlatformVersionDeprecated => self.platform_version(),
-            LoweredMarkerValueString::SysPlatform
-            | LoweredMarkerValueString::SysPlatformDeprecated => self.sys_platform(),
+            LoweredMarkerValueString::PlatformVersion => self.platform_version(),
+            LoweredMarkerValueString::SysPlatform => self.sys_platform(),
         }
     }
 }

crates/uv-pep508/src/marker/lowering.rs

@@ -53,53 +53,40 @@ pub enum LoweredMarkerValueString {
     ImplementationName,
     /// `os_name`
     OsName,
-    /// Deprecated `os.name` from <https://peps.python.org/pep-0345/#environment-markers>
-    OsNameDeprecated,
     /// `platform_machine`
     PlatformMachine,
     /// Deprecated `platform.machine` from <https://peps.python.org/pep-0345/#environment-markers>
-    PlatformMachineDeprecated,
     /// `platform_python_implementation`
     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`
     PlatformSystem,
     /// `platform_version`
     PlatformVersion,
-    /// Deprecated `platform.version` from <https://peps.python.org/pep-0345/#environment-markers>
-    PlatformVersionDeprecated,
     /// `sys_platform`
     SysPlatform,
-    /// Deprecated `sys.platform` from <https://peps.python.org/pep-0345/#environment-markers>
-    SysPlatformDeprecated,
 }
 
 impl From<MarkerValueString> for LoweredMarkerValueString {
     fn from(value: MarkerValueString) -> Self {
         match value {
             MarkerValueString::ImplementationName => Self::ImplementationName,
             MarkerValueString::OsName => Self::OsName,
-            MarkerValueString::OsNameDeprecated => Self::OsNameDeprecated,
+            MarkerValueString::OsNameDeprecated => Self::OsName,
             MarkerValueString::PlatformMachine => Self::PlatformMachine,
-            MarkerValueString::PlatformMachineDeprecated => Self::PlatformMachineDeprecated,
+            MarkerValueString::PlatformMachineDeprecated => Self::PlatformMachine,
             MarkerValueString::PlatformPythonImplementation => Self::PlatformPythonImplementation,
             MarkerValueString::PlatformPythonImplementationDeprecated => {
-                Self::PlatformPythonImplementationDeprecated
-            }
-            MarkerValueString::PythonImplementationDeprecated => {
-                Self::PythonImplementationDeprecated
+                Self::PlatformPythonImplementation
             }
+            MarkerValueString::PythonImplementationDeprecated => Self::PlatformPythonImplementation,
             MarkerValueString::PlatformRelease => Self::PlatformRelease,
             MarkerValueString::PlatformSystem => Self::PlatformSystem,
             MarkerValueString::PlatformVersion => Self::PlatformVersion,
-            MarkerValueString::PlatformVersionDeprecated => Self::PlatformVersionDeprecated,
+            MarkerValueString::PlatformVersionDeprecated => Self::PlatformVersion,
             MarkerValueString::SysPlatform => Self::SysPlatform,
-            MarkerValueString::SysPlatformDeprecated => Self::SysPlatformDeprecated,
+            MarkerValueString::SysPlatformDeprecated => Self::SysPlatform,
         }
     }
 }
@@ -109,24 +96,14 @@ impl From<LoweredMarkerValueString> for MarkerValueString {
         match value {
             LoweredMarkerValueString::ImplementationName => Self::ImplementationName,
             LoweredMarkerValueString::OsName => Self::OsName,
-            LoweredMarkerValueString::OsNameDeprecated => Self::OsNameDeprecated,
             LoweredMarkerValueString::PlatformMachine => Self::PlatformMachine,
-            LoweredMarkerValueString::PlatformMachineDeprecated => Self::PlatformMachineDeprecated,
             LoweredMarkerValueString::PlatformPythonImplementation => {
                 Self::PlatformPythonImplementation
             }
-            LoweredMarkerValueString::PlatformPythonImplementationDeprecated => {
-                Self::PlatformPythonImplementationDeprecated
-            }
-            LoweredMarkerValueString::PythonImplementationDeprecated => {
-                Self::PythonImplementationDeprecated
-            }
             LoweredMarkerValueString::PlatformRelease => Self::PlatformRelease,
             LoweredMarkerValueString::PlatformSystem => Self::PlatformSystem,
             LoweredMarkerValueString::PlatformVersion => Self::PlatformVersion,
-            LoweredMarkerValueString::PlatformVersionDeprecated => Self::PlatformVersionDeprecated,
             LoweredMarkerValueString::SysPlatform => Self::SysPlatform,
-            LoweredMarkerValueString::SysPlatformDeprecated => Self::SysPlatformDeprecated,
         }
     }
 }
@@ -136,19 +113,13 @@ impl Display for LoweredMarkerValueString {
     fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
         match self {
             Self::ImplementationName => f.write_str("implementation_name"),
-            Self::OsName | Self::OsNameDeprecated => f.write_str("os_name"),
-            Self::PlatformMachine | Self::PlatformMachineDeprecated => {
-                f.write_str("platform_machine")
-            }
-            Self::PlatformPythonImplementation
-            | Self::PlatformPythonImplementationDeprecated
-            | Self::PythonImplementationDeprecated => f.write_str("platform_python_implementation"),
+            Self::OsName => f.write_str("os_name"),
+            Self::PlatformMachine => f.write_str("platform_machine"),
+            Self::PlatformPythonImplementation => f.write_str("platform_python_implementation"),
             Self::PlatformRelease => f.write_str("platform_release"),
             Self::PlatformSystem => f.write_str("platform_system"),
-            Self::PlatformVersion | Self::PlatformVersionDeprecated => {
-                f.write_str("platform_version")
-            }
-            Self::SysPlatform | Self::SysPlatformDeprecated => f.write_str("sys_platform"),
+            Self::PlatformVersion => f.write_str("platform_version"),
+            Self::SysPlatform => f.write_str("sys_platform"),
         }
     }
 }

crates/uv/tests/it/pip_compile.rs

@@ -13626,3 +13626,36 @@ fn compile_derivation_chain() -> Result<()> {
 
     Ok(())
 }
+
+/// Treat `sys_platform` and `sys.platform` as equivalent markers in the marker algebra.
+#[test]
+fn universal_disjoint_deprecated_markers() -> Result<()> {
+    let context = TestContext::new("3.12");
+    let requirements_in = context.temp_dir.child("requirements.in");
+    requirements_in.write_str(indoc::indoc! {r"
+        anyio ; sys_platform == 'win32' and sys.platform == 'win32'
+        typing-extensions ; platform.python_implementation == 'CPython' and python_implementation != 'CPython'
+    "})?;
+
+    uv_snapshot!(context.filters(), context.pip_compile()
+            .arg("requirements.in")
+            .arg("--universal"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    # This file was autogenerated by uv via the following command:
+    #    uv pip compile --cache-dir [CACHE_DIR] requirements.in --universal
+    anyio==4.3.0 ; sys_platform == 'win32'
+        # via -r requirements.in
+    idna==3.6 ; sys_platform == 'win32'
+        # via anyio
+    sniffio==1.3.1 ; sys_platform == 'win32'
+        # via anyio
+
+    ----- stderr -----
+    Resolved 3 packages in [TIME]
+    "###
+    );
+
+    Ok(())
+}