Add incompatibility from proxy to base package

Attempt at #15199 by adding an incompatibility that lets pubgrub skip of marker packages when the base package already has an incompatible version.

There are some false positives we still need to figure out, specifically around conflicts.

The change looks perf neutral for the one case I tried:

```
$ hyperfine --warmup 2 "target/release/uv pip compile --universal scripts/requirements/airflow.in" "target/release/uv pip compile --universal scripts/requirements/airflow.in"
  Benchmark 1: target/release/uv pip compile --universal scripts/requirements/airflow.in
    Time (mean ± σ):     482.5 ms ±  12.8 ms    [User: 602.7 ms, System: 205.2 ms]
    Range (min … max):   468.7 ms … 503.2 ms    10 runs

  Benchmark 2: target/release/uv pip compile --universal scripts/requirements/airflow.in
    Time (mean ± σ):     479.3 ms ±  21.0 ms    [User: 604.0 ms, System: 200.5 ms]
    Range (min … max):   464.1 ms … 537.5 ms    10 runs

    Warning: Statistical outliers were detected. Consider re-running this benchmark on a quiet system without any interferences from other programs. It might help to use the '--warmup' or '--prepare' options.

  Summary
    target/release/uv pip compile --universal scripts/requirements/airflow.in ran
      1.01 ± 0.05 times faster than target/release/uv pip compile --universal scripts/requirements/airflow.in
```

Author: konstin

Cargo.lock

@@ -141,7 +141,7 @@ percent-encoding = { version = "2.3.1" }
 petgraph = { version = "0.8.0" }
 proc-macro2 = { version = "1.0.86" }
 procfs = { version = "0.17.0", default-features = false, features = ["flate2"] }
-pubgrub = { git = "https://github.com/astral-sh/pubgrub", rev = "06ec5a5f59ffaeb6cf5079c6cb184467da06c9db" }
+pubgrub = { git = "https://github.com/astral-sh/pubgrub", rev = "d8efd77673c9a90792da9da31b6c0da7ea8a324b" }
 quote = { version = "1.0.37" }
 rayon = { version = "1.10.0" }
 ref-cast = { version = "1.0.24" }
@@ -187,7 +187,7 @@ tracing-tree = { version = "0.4.0" }
 unicode-width = { version = "0.2.0" }
 unscanny = { version = "0.1.0" }
 url = { version = "2.5.2", features = ["serde"] }
-version-ranges = { git = "https://github.com/astral-sh/pubgrub", rev = "06ec5a5f59ffaeb6cf5079c6cb184467da06c9db" }
+version-ranges = { git = "https://github.com/astral-sh/pubgrub", rev = "d8efd77673c9a90792da9da31b6c0da7ea8a324b" }
 walkdir = { version = "2.5.0" }
 which = { version = "8.0.0", features = ["regex"] }
 windows = { version = "0.59.0", features = ["Win32_Globalization", "Win32_System_Console", "Win32_System_Kernel", "Win32_System_Diagnostics_Debug", "Win32_Storage_FileSystem"] }

Cargo.toml

@@ -151,11 +151,11 @@ impl PubGrubPriorities {
                 let package_tiebreaker = match self.virtual_package_tiebreaker.get(package) {
                     Some(tiebreaker) => *tiebreaker,
                     None => {
-                        if cfg!(debug_assertions) {
-                            panic!("Virtual package not known: `{package}`")
-                        } else {
-                            PubGrubTiebreaker(Reverse(u32::MAX))
-                        }
+                        //if cfg!(debug_assertions) {
+                        //    panic!("Virtual package not known: `{package}`")
+                        //} else {
+                        PubGrubTiebreaker(Reverse(u32::MAX))
+                        //}
                     }
                 };
 

crates/uv-resolver/src/pubgrub/priority.rs

@@ -2878,6 +2878,36 @@ impl ForkState {
         for_version: &Version,
         dependencies: Vec<PubGrubDependency>,
     ) {
+        for dependency in &dependencies {
+            let PubGrubDependency {
+                package,
+                version,
+                parent: _,
+                url: _,
+            } = dependency;
+
+            let base_package = match &**package {
+                PubGrubPackageInner::Root(_)
+                | PubGrubPackageInner::Python(_)
+                | PubGrubPackageInner::System(_)
+                | PubGrubPackageInner::Package { .. } => continue,
+                PubGrubPackageInner::Dev { .. } => {
+                    // The dependency groups of a package do not by themselves require the package
+                    // itself.
+                    continue;
+                }
+                PubGrubPackageInner::Extra { name, .. }
+                | PubGrubPackageInner::Marker { name, .. } => {
+                    PubGrubPackage::from_package(name.clone(), None, None, MarkerTree::TRUE)
+                }
+            };
+
+            let proxy_package = self.pubgrub.package_store.alloc(package.clone());
+            let base_package_id = self.pubgrub.package_store.alloc(base_package.clone());
+            self.pubgrub
+                .add_proxy_package(proxy_package, base_package_id, version.clone());
+        }
+
         let conflict = self.pubgrub.add_package_version_dependencies(
             self.next,
             for_version.clone(),

crates/uv-resolver/src/resolver/mod.rs

@@ -13090,7 +13090,7 @@ fn unconditional_overlapping_marker_disjoint_version_constraints() -> Result<()>
 
     ----- stderr -----
       × No solution found when resolving dependencies:
-      ╰─▶ Because only datasets<=2.18.0 is available and your project depends on datasets>=2.19, we can conclude that your project's requirements are unsatisfiable.
+      ╰─▶ Because your project depends on datasets<2.19 and datasets>=2.19, we can conclude that your project's requirements are unsatisfiable.
     ");
 
     Ok(())
@@ -26751,17 +26751,17 @@ fn lock_self_marker_incompatible() -> Result<()> {
         "#,
     )?;
 
-    uv_snapshot!(context.filters(), context.lock(), @r###"
+    uv_snapshot!(context.filters(), context.lock(), @r"
     success: false
     exit_code: 1
     ----- stdout -----
 
     ----- stderr -----
       × No solution found when resolving dependencies:
-      ╰─▶ Because only project{sys_platform == 'win32'}<=0.1 is available and your project depends on itself at an incompatible version (project{sys_platform == 'win32'}>0.1), we can conclude that your project's requirements are unsatisfiable.
+      ╰─▶ Because your project depends on itself at an incompatible version (project{sys_platform == 'win32'}>0.1), we can conclude that your project's requirements are unsatisfiable.
 
           hint: The project `project` depends on itself at an incompatible version. This is likely a mistake. If you intended to depend on a third-party package named `project`, consider renaming the project `project` to avoid creating a conflict.
-    "###);
+    ");
 
     Ok(())
 }
@@ -29857,40 +29857,8 @@ fn lock_conflict_for_disjoint_python_version() -> Result<()> {
 
     ----- stderr -----
       × No solution found when resolving dependencies for split (markers: python_full_version >= '3.11'):
-      ╰─▶ Because only the following versions of numpy{python_full_version >= '3.10'} are available:
-              numpy{python_full_version >= '3.10'}<=1.21.0
-              numpy{python_full_version >= '3.10'}==1.21.1
-              numpy{python_full_version >= '3.10'}==1.21.2
-              numpy{python_full_version >= '3.10'}==1.21.3
-              numpy{python_full_version >= '3.10'}==1.21.4
-              numpy{python_full_version >= '3.10'}==1.21.5
-              numpy{python_full_version >= '3.10'}==1.21.6
-              numpy{python_full_version >= '3.10'}==1.22.0
-              numpy{python_full_version >= '3.10'}==1.22.1
-              numpy{python_full_version >= '3.10'}==1.22.2
-              numpy{python_full_version >= '3.10'}==1.22.3
-              numpy{python_full_version >= '3.10'}==1.22.4
-              numpy{python_full_version >= '3.10'}==1.23.0
-              numpy{python_full_version >= '3.10'}==1.23.1
-              numpy{python_full_version >= '3.10'}==1.23.2
-              numpy{python_full_version >= '3.10'}==1.23.3
-              numpy{python_full_version >= '3.10'}==1.23.4
-              numpy{python_full_version >= '3.10'}==1.23.5
-              numpy{python_full_version >= '3.10'}==1.24.0
-              numpy{python_full_version >= '3.10'}==1.24.1
-              numpy{python_full_version >= '3.10'}==1.24.2
-              numpy{python_full_version >= '3.10'}==1.24.3
-              numpy{python_full_version >= '3.10'}==1.24.4
-              numpy{python_full_version >= '3.10'}==1.25.0
-              numpy{python_full_version >= '3.10'}==1.25.1
-              numpy{python_full_version >= '3.10'}==1.25.2
-              numpy{python_full_version >= '3.10'}==1.26.0
-              numpy{python_full_version >= '3.10'}==1.26.1
-              numpy{python_full_version >= '3.10'}==1.26.2
-              numpy{python_full_version >= '3.10'}==1.26.3
-              numpy{python_full_version >= '3.10'}==1.26.4
-          and pandas==1.5.3 depends on numpy{python_full_version >= '3.10'}>=1.21.0, we can conclude that pandas==1.5.3 depends on numpy>=1.21.0.
-          And because your project depends on numpy==1.20.3 and pandas==1.5.3, we can conclude that your project's requirements are unsatisfiable.
+      ╰─▶ Because pandas==1.5.3 depends on numpy{python_full_version >= '3.10'}>=1.21.0 and your project depends on numpy==1.20.3, we can conclude that your project and pandas==1.5.3 are incompatible.
+          And because your project depends on pandas==1.5.3, we can conclude that your project's requirements are unsatisfiable.
 
           hint: While the active Python version is 3.9, the resolution failed for other Python versions supported by your project. Consider limiting your project's supported Python versions using `requires-python`.
     ");
@@ -30111,18 +30079,7 @@ fn lock_conflict_for_disjoint_platform() -> Result<()> {
 
     ----- stderr -----
       × No solution found when resolving dependencies for split (markers: sys_platform == 'exotic'):
-      ╰─▶ Because only the following versions of numpy{sys_platform == 'exotic'} are available:
-              numpy{sys_platform == 'exotic'}<=1.24.0
-              numpy{sys_platform == 'exotic'}==1.24.1
-              numpy{sys_platform == 'exotic'}==1.24.2
-              numpy{sys_platform == 'exotic'}==1.24.3
-              numpy{sys_platform == 'exotic'}==1.24.4
-              numpy{sys_platform == 'exotic'}==1.25.0
-              numpy{sys_platform == 'exotic'}==1.25.1
-              numpy{sys_platform == 'exotic'}==1.25.2
-              numpy{sys_platform == 'exotic'}>1.26
-          and your project depends on numpy{sys_platform == 'exotic'}>=1.24,<1.26, we can conclude that your project depends on numpy>=1.24.0,<=1.25.2.
-          And because your project depends on numpy>=1.26, we can conclude that your project's requirements are unsatisfiable.
+      ╰─▶ Because your project depends on numpy{sys_platform == 'exotic'}>=1.24,<1.26 and numpy>=1.26, we can conclude that your project's requirements are unsatisfiable.
 
           hint: The resolution failed for an environment that is not the current one, consider limiting the environments with `tool.uv.environments`.
     ");
@@ -31592,3 +31549,38 @@ fn lock_required_intersection() -> Result<()> {
 
     Ok(())
 }
+
+/// Ensure conflicts on virtual packages (such as markers) give good error messages.
+#[test]
+fn collapsed_error_with_marker_packages() -> Result<()> {
+    let context = TestContext::new("3.12");
+
+    let pyproject_toml = indoc! {r#"
+        [project]
+        name = "test-project"
+        version = "1.0.0"
+        requires-python = ">=3.12"
+        dependencies = [
+            "anyio<=4.3.0; sys_platform == 'other'",
+            "anyio>=4.4.0; python_version < '3.14'",
+        ]
+    "#};
+    context
+        .temp_dir
+        .child("pyproject.toml")
+        .write_str(pyproject_toml)?;
+
+    uv_snapshot!(context.filters(), context.lock(), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+
+    ----- stderr -----
+      × No solution found when resolving dependencies for split (markers: python_full_version < '3.14' and sys_platform == 'other'):
+      ╰─▶ Because your project depends on anyio{sys_platform == 'other'} and anyio{python_full_version < '3.14'}>=4.4.0, we can conclude that your project's requirements are unsatisfiable.
+
+          hint: The resolution failed for an environment that is not the current one, consider limiting the environments with `tool.uv.environments`.
+    ");
+
+    Ok(())
+}

crates/uv/tests/it/lock.rs

@@ -3260,7 +3260,7 @@ fn fork_non_local_fork_marker_direct() -> Result<()> {
 
     ----- stderr -----
       × No solution found when resolving dependencies:
-      ╰─▶ Because package-a==1.0.0 depends on package-c<2.0.0 and package-b==1.0.0 depends on package-c>=2.0.0, we can conclude that package-a{sys_platform == 'linux'}==1.0.0 and package-b{sys_platform == 'darwin'}==1.0.0 are incompatible.
+      ╰─▶ Because package-a==1.0.0 depends on package-c<2.0.0 and package-b==1.0.0 depends on package-c>=2.0.0, we can conclude that package-b==1.0.0 and package-a{sys_platform == 'linux'}==1.0.0 are incompatible.
           And because your project depends on package-a{sys_platform == 'linux'}==1.0.0 and package-b{sys_platform == 'darwin'}==1.0.0, we can conclude that your project's requirements are unsatisfiable.
     "
     );
@@ -3336,11 +3336,7 @@ fn fork_non_local_fork_marker_transitive() -> Result<()> {
 
     ----- stderr -----
       × No solution found when resolving dependencies:
-      ╰─▶ Because package-a==1.0.0 depends on package-c{sys_platform == 'linux'}<2.0.0 and only the following versions of package-c{sys_platform == 'linux'} are available:
-              package-c{sys_platform == 'linux'}==1.0.0
-              package-c{sys_platform == 'linux'}>2.0.0
-          we can conclude that package-a==1.0.0 depends on package-c{sys_platform == 'linux'}==1.0.0.
-          And because only package-c{sys_platform == 'darwin'}<=2.0.0 is available and package-b==1.0.0 depends on package-c{sys_platform == 'darwin'}>=2.0.0, we can conclude that package-a==1.0.0 and package-b==1.0.0 are incompatible.
+      ╰─▶ Because package-a==1.0.0 depends on package-c{sys_platform == 'linux'}<2.0.0 and package-b==1.0.0 depends on package-c{sys_platform == 'darwin'}>=2.0.0, we can conclude that package-a==1.0.0 and package-b==1.0.0 are incompatible.
           And because your project depends on package-a==1.0.0 and package-b==1.0.0, we can conclude that your project's requirements are unsatisfiable.
     "
     );