Add `--upgrade` support to `pip install` (#1379)

Adds support for `--upgrade` — similar to `--reinstall`.

Closes https://github.com/astral-sh/uv/issues/1391

crates/uv-installer/src/plan.rs

@@ -467,4 +467,9 @@ impl Reinstall {
     pub fn is_none(&self) -> bool {
         matches!(self, Self::None)
     }
+
+    /// Returns `true` if all packages should be reinstalled.
+    pub fn is_all(&self) -> bool {
+        matches!(self, Self::All)
+    }
 }

crates/uv/src/commands/pip_compile.rs

@@ -425,6 +425,11 @@ impl Upgrade {
         }
     }
 
+    /// Returns `true` if no packages should be upgraded.
+    pub(crate) fn is_none(&self) -> bool {
+        matches!(self, Self::None)
+    }
+
     /// Returns `true` if all packages should be upgraded.
     pub(crate) fn is_all(&self) -> bool {
         matches!(self, Self::All)

crates/uv/src/commands/pip_install.rs

@@ -1,4 +1,6 @@
+use std::collections::HashSet;
 use std::fmt::Write;
+
 use std::path::Path;
 
 use anstream::eprint;
@@ -38,6 +40,8 @@ use crate::commands::{elapsed, ChangeEvent, ChangeEventKind, ExitStatus};
 use crate::printer::Printer;
 use crate::requirements::{ExtrasSpecification, RequirementsSource, RequirementsSpecification};
 
+use super::Upgrade;
+
 /// Install packages into the current environment.
 #[allow(clippy::too_many_arguments)]
 pub(crate) async fn pip_install(
@@ -48,6 +52,7 @@ pub(crate) async fn pip_install(
     resolution_mode: ResolutionMode,
     prerelease_mode: PreReleaseMode,
     dependency_mode: DependencyMode,
+    upgrade: Upgrade,
     index_locations: IndexLocations,
     reinstall: &Reinstall,
     link_mode: LinkMode,
@@ -115,7 +120,10 @@ pub(crate) async fn pip_install(
     // If the requirements are already satisfied, we're done. Ideally, the resolver would be fast
     // enough to let us remove this check. But right now, for large environments, it's an order of
     // magnitude faster to validate the environment than to resolve the requirements.
-    if reinstall.is_none() && site_packages.satisfies(&requirements, &editables, &constraints)? {
+    if reinstall.is_none()
+        && upgrade.is_none()
+        && site_packages.satisfies(&requirements, &editables, &constraints)?
+    {
         let num_requirements = requirements.len() + editables.len();
         let s = if num_requirements == 1 { "" } else { "s" };
         writeln!(
@@ -206,6 +214,7 @@ pub(crate) async fn pip_install(
         &editables,
         &site_packages,
         reinstall,
+        &upgrade,
         &interpreter,
         tags,
         markers,
@@ -378,6 +387,7 @@ async fn resolve(
     editables: &[BuiltEditable],
     site_packages: &SitePackages<'_>,
     reinstall: &Reinstall,
+    upgrade: &Upgrade,
     interpreter: &Interpreter,
     tags: &Tags,
     markers: &MarkerEnvironment,
@@ -390,14 +400,25 @@ async fn resolve(
 ) -> Result<ResolutionGraph, Error> {
     let start = std::time::Instant::now();
 
-    // Respect preferences from the existing environments.
+    let preferences = if upgrade.is_all() || reinstall.is_all() {
-    let preferences: Vec<Requirement> = match reinstall {
+        vec![]
-        Reinstall::All => vec![],
+    } else {
-        Reinstall::None => site_packages.requirements().collect(),
+        // Combine upgrade and reinstall lists
-        Reinstall::Packages(packages) => site_packages
+        let mut exclusions: HashSet<&PackageName> = if let Reinstall::Packages(packages) = reinstall
+        {
+            HashSet::from_iter(packages)
+        } else {
+            HashSet::default()
+        };
+        if let Upgrade::Packages(packages) = upgrade {
+            exclusions.extend(packages);
+        };
+
+        // Prefer current site packages, unless in the upgrade or reinstall lists
+        site_packages
             .requirements()
-            .filter(|requirement| !packages.contains(&requirement.name))
+            .filter(|requirement| !exclusions.contains(&requirement.name))
-            .collect(),
+            .collect()
     };
 
     // Map the editables to their metadata.

crates/uv/src/main.rs

@@ -470,6 +470,14 @@ struct PipInstallArgs {
     #[clap(long, conflicts_with = "extra")]
     all_extras: bool,
 
+    /// Allow package upgrades.
+    #[clap(long)]
+    upgrade: bool,
+
+    /// Allow upgrade of a specific package.
+    #[clap(long)]
+    upgrade_package: Vec<PackageName>,
+
     /// Reinstall all packages, regardless of whether they're already installed.
     #[clap(long, alias = "force-reinstall")]
     reinstall: bool,
@@ -935,6 +943,7 @@ async fn run() -> Result<ExitStatus> {
                 ExtrasSpecification::Some(&args.extra)
             };
             let reinstall = Reinstall::from_args(args.reinstall, args.reinstall_package);
+            let upgrade = Upgrade::from_args(args.upgrade, args.upgrade_package);
             let no_binary = NoBinary::from_args(args.no_binary);
             let no_build = NoBuild::from_args(args.only_binary, args.no_build);
             let dependency_mode = if args.no_deps {
@@ -950,6 +959,7 @@ async fn run() -> Result<ExitStatus> {
                 args.resolution,
                 args.prerelease,
                 dependency_mode,
+                upgrade,
                 index_urls,
                 &reinstall,
                 args.link_mode,

crates/uv/tests/pip_install.rs

@@ -160,7 +160,7 @@ fn install_requirements_txt() -> Result<()> {
 
 /// Respect installed versions when resolving.
 #[test]
-fn respect_installed() -> Result<()> {
+fn respect_installed_and_reinstall() -> Result<()> {
     let context = TestContext::new("3.12");
 
     // Install Flask.
@@ -268,6 +268,29 @@ fn respect_installed() -> Result<()> {
     "###
     );
 
+    // Re-install Flask. We should install even though the version is current
+    let requirements_txt = context.temp_dir.child("requirements.txt");
+    requirements_txt.touch()?;
+    requirements_txt.write_str("Flask")?;
+
+    uv_snapshot!(filters, command(&context)
+        .arg("-r")
+        .arg("requirements.txt")
+        .arg("--reinstall-package")
+        .arg("Flask")
+        .arg("--strict"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    Resolved 7 packages in [TIME]
+    Installed 1 package in [TIME]
+     - flask==3.0.0
+     + flask==3.0.0
+    "###
+    );
+
     Ok(())
 }
 
@@ -894,3 +917,98 @@ fn no_deps() {
 
     context.assert_command("import flask").failure();
 }
+
+/// Upgrade a package.
+#[test]
+fn install_upgrade() {
+    let context = TestContext::new("3.12");
+
+    // Install an old version of anyio and httpcore.
+    uv_snapshot!(command(&context)
+        .arg("anyio==3.6.2")
+        .arg("httpcore==0.16.3")
+        .arg("--strict"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    Resolved 6 packages in [TIME]
+    Downloaded 6 packages in [TIME]
+    Installed 6 packages in [TIME]
+     + anyio==3.6.2
+     + certifi==2023.11.17
+     + h11==0.14.0
+     + httpcore==0.16.3
+     + idna==3.4
+     + sniffio==1.3.0
+    "###
+    );
+
+    context.assert_command("import anyio").success();
+
+    // Upgrade anyio.
+    uv_snapshot!(command(&context)
+        .arg("anyio")
+        .arg("--upgrade-package")
+        .arg("anyio"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    Resolved 3 packages in [TIME]
+    Downloaded 1 package in [TIME]
+    Installed 1 package in [TIME]
+     - anyio==3.6.2
+     + anyio==4.0.0
+    "###
+    );
+
+    // Upgrade anyio again, should not reinstall.
+    uv_snapshot!(command(&context)
+        .arg("anyio")
+        .arg("--upgrade-package")
+        .arg("anyio"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    Resolved 3 packages in [TIME]
+    Audited 3 packages in [TIME]
+    "###
+    );
+
+    // Install httpcore, request anyio upgrade should not reinstall
+    uv_snapshot!(command(&context)
+        .arg("httpcore")
+        .arg("--upgrade-package")
+        .arg("anyio"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    Resolved 6 packages in [TIME]
+    Audited 6 packages in [TIME]
+    "###
+    );
+
+    // Upgrade httpcore with global flag
+    uv_snapshot!(command(&context)
+        .arg("httpcore")
+        .arg("--upgrade"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    Resolved 3 packages in [TIME]
+    Downloaded 1 package in [TIME]
+    Installed 1 package in [TIME]
+     - httpcore==0.16.3
+     + httpcore==1.0.2
+    "###
+    );
+}