Avoid always rebuilding dynamic metadata (#5206)

## Summary

I don't think that "always reinstall" is tenable for `uv run`. My
perspective on this is that if you want "always reinstall", you can now
set it persistently in your `pyproject.toml` or `uv.toml`.

As a smaller change, we could instead disable this _only_ for the
Project API.

Closes https://github.com/astral-sh/uv/issues/4946.

Cargo.lock

@@ -4867,11 +4867,9 @@ dependencies = [
  "rayon",
  "rustc-hash 2.0.0",
  "same-file",
- "serde",
  "tempfile",
  "thiserror",
  "tokio",
- "toml",
  "tracing",
  "url",
  "uv-cache",

crates/uv-installer/Cargo.toml

@@ -39,11 +39,9 @@ futures = { workspace = true }
 rayon = { workspace = true }
 rustc-hash = { workspace = true }
 same-file = { workspace = true }
-serde = { workspace = true }
 tempfile = { workspace = true }
 thiserror = { workspace = true }
 tokio = { workspace = true }
-toml = { workspace = true }
 tracing = { workspace = true }
 url = { workspace = true }
 walkdir = { workspace = true }

crates/uv-installer/src/plan.rs

@@ -123,9 +123,6 @@ impl<'a> Planner<'a> {
                             RequirementSatisfaction::OutOfDate => {
                                 debug!("Requirement installed, but not fresh: {distribution}");
                             }
-                            RequirementSatisfaction::Dynamic => {
-                                debug!("Requirement installed, but dynamic: {distribution}");
-                            }
                         }
                         reinstalls.push(distribution.clone());
                     }

crates/uv-installer/src/satisfies.rs

@@ -1,9 +1,6 @@
 use std::fmt::Debug;
-use std::path::Path;
 
-use anyhow::Result;
 use same_file::is_same_file;
-use serde::Deserialize;
 use tracing::{debug, trace};
 use url::Url;
 
@@ -17,14 +14,16 @@ pub(crate) enum RequirementSatisfaction {
     Mismatch,
     Satisfied,
     OutOfDate,
-    Dynamic,
 }
 
 impl RequirementSatisfaction {
     /// Returns true if a requirement is satisfied by an installed distribution.
     ///
     /// Returns an error if IO fails during a freshness check for a local path.
-    pub(crate) fn check(distribution: &InstalledDist, source: &RequirementSource) -> Result<Self> {
+    pub(crate) fn check(
+        distribution: &InstalledDist,
+        source: &RequirementSource,
+    ) -> anyhow::Result<Self> {
         trace!(
             "Comparing installed with source: {:?} {:?}",
             distribution,
@@ -250,59 +249,8 @@ impl RequirementSatisfaction {
                     return Ok(Self::OutOfDate);
                 }
 
-                // Does the package have dynamic metadata?
-                if is_dynamic(requested_path) {
-                    trace!("Dependency is dynamic");
-                    return Ok(Self::Dynamic);
-                }
-
                 Ok(Self::Satisfied)
             }
         }
     }
 }
-
-/// Returns `true` if the source tree at the given path contains dynamic metadata.
-fn is_dynamic(path: &Path) -> bool {
-    // If there's no `pyproject.toml`, we assume it's dynamic.
-    let Ok(contents) = fs_err::read_to_string(path.join("pyproject.toml")) else {
-        return true;
-    };
-    let Ok(pyproject_toml) = toml::from_str::<PyProjectToml>(&contents) else {
-        return true;
-    };
-    // If `[project]` is not present, we assume it's dynamic.
-    let Some(project) = pyproject_toml.project else {
-        // ...unless it appears to be a Poetry project.
-        return pyproject_toml
-            .tool
-            .map_or(true, |tool| tool.poetry.is_none());
-    };
-    // `[project.dynamic]` must be present and non-empty.
-    project.dynamic.is_some_and(|dynamic| !dynamic.is_empty())
-}
-
-/// A pyproject.toml as specified in PEP 517.
-#[derive(Deserialize, Debug)]
-#[serde(rename_all = "kebab-case")]
-struct PyProjectToml {
-    project: Option<Project>,
-    tool: Option<Tool>,
-}
-
-#[derive(Deserialize, Debug)]
-#[serde(rename_all = "kebab-case")]
-struct Project {
-    dynamic: Option<Vec<String>>,
-}
-
-#[derive(Deserialize, Debug)]
-struct Tool {
-    poetry: Option<ToolPoetry>,
-}
-
-#[derive(Deserialize, Debug)]
-struct ToolPoetry {
-    #[allow(dead_code)]
-    name: Option<String>,
-}

crates/uv-installer/src/site_packages.rs

@@ -311,9 +311,7 @@ impl SitePackages {
                         distribution,
                         entry.requirement.source().as_ref(),
                     )? {
-                        RequirementSatisfaction::Mismatch
-                        | RequirementSatisfaction::OutOfDate
-                        | RequirementSatisfaction::Dynamic => {
+                        RequirementSatisfaction::Mismatch | RequirementSatisfaction::OutOfDate => {
                             return Ok(SatisfiesResult::Unsatisfied(entry.requirement.to_string()))
                         }
                         RequirementSatisfaction::Satisfied => {}
@@ -323,8 +321,7 @@ impl SitePackages {
                     for constraint in constraints.get(&distribution.name()).into_iter().flatten() {
                         match RequirementSatisfaction::check(distribution, &constraint.source)? {
                             RequirementSatisfaction::Mismatch
-                            | RequirementSatisfaction::OutOfDate
-                            | RequirementSatisfaction::Dynamic => {
+                            | RequirementSatisfaction::OutOfDate => {
                                 return Ok(SatisfiesResult::Unsatisfied(
                                     entry.requirement.to_string(),
                                 ))

crates/uv/tests/pip_install.rs

@@ -3051,10 +3051,10 @@ requires-python = ">=3.8"
 }
 
 #[test]
-fn invalidate_editable_dynamic() -> Result<()> {
+fn editable_dynamic() -> Result<()> {
     let context = TestContext::new("3.12");
 
-    // Create an editable package with dynamic metadata
+    // Create an editable package with dynamic metadata.
     let editable_dir = context.temp_dir.child("editable");
     editable_dir.create_dir_all()?;
     let pyproject_toml = editable_dir.child("pyproject.toml");
@@ -3092,7 +3092,7 @@ dependencies = {file = ["requirements.txt"]}
     "###
     );
 
-    // Re-installing should re-install.
+    // Re-installing should not re-install, as we don't special-case dynamic metadata.
     uv_snapshot!(context.filters(), context.pip_install()
         .arg("--editable")
         .arg(editable_dir.path()), @r###"
@@ -3101,35 +3101,7 @@ dependencies = {file = ["requirements.txt"]}
     ----- stdout -----
 
     ----- stderr -----
-    Resolved 4 packages in [TIME]
-    Prepared 1 package in [TIME]
-    Uninstalled 1 package in [TIME]
-    Installed 1 package in [TIME]
-     - example==0.1.0 (from file://[TEMP_DIR]/editable)
-     + example==0.1.0 (from file://[TEMP_DIR]/editable)
-    "###
-    );
-
-    // Modify the requirements.
-    requirements_txt.write_str("anyio==3.7.1")?;
-
-    // Re-installing should update the package.
-    uv_snapshot!(context.filters(), context.pip_install()
-        .arg("--editable")
-        .arg(editable_dir.path()), @r###"
-    success: true
-    exit_code: 0
-    ----- stdout -----
-
-    ----- stderr -----
-    Resolved 4 packages in [TIME]
-    Prepared 2 packages in [TIME]
-    Uninstalled 2 packages in [TIME]
-    Installed 2 packages in [TIME]
-     - anyio==4.0.0
-     + anyio==3.7.1
-     - example==0.1.0 (from file://[TEMP_DIR]/editable)
-     + example==0.1.0 (from file://[TEMP_DIR]/editable)
+    Audited 1 package in [TIME]
     "###
     );