Add index URLs when provided via uv add --index or --default-index

crates/uv-cli/src/lib.rs

@@ -768,6 +768,10 @@ impl<T> Maybe<T> {
             Maybe::None => None,
         }
     }
+
+    pub fn is_some(&self) -> bool {
+        matches!(self, Maybe::Some(_))
+    }
 }
 
 /// Parse a string into an [`IndexUrl`], mapping the empty string to `None`.

crates/uv-workspace/src/pyproject_mut.rs

@@ -3,7 +3,8 @@ use std::path::Path;
 use std::str::FromStr;
 use std::{fmt, mem};
 use thiserror::Error;
-use toml_edit::{Array, DocumentMut, Item, RawString, Table, TomlError, Value};
+use toml_edit::{Array, ArrayOfTables, DocumentMut, Item, RawString, Table, TomlError, Value};
+use uv_distribution_types::Index;
 use uv_fs::PortablePath;
 use uv_pep440::{Version, VersionSpecifier, VersionSpecifiers};
 use uv_pep508::{ExtraName, MarkerTree, PackageName, Requirement, VersionOrUrl};
@@ -190,6 +191,88 @@ impl PyProjectTomlMut {
         Ok(edit)
     }
 
+    /// Add an [`Index`] to `tool.uv.index`.
+    pub fn add_index(&mut self, index: &Index) -> Result<(), Error> {
+        let existing = self
+            .doc
+            .entry("tool")
+            .or_insert(implicit())
+            .as_table_mut()
+            .ok_or(Error::MalformedSources)?
+            .entry("uv")
+            .or_insert(implicit())
+            .as_table_mut()
+            .ok_or(Error::MalformedSources)?
+            .entry("index")
+            .or_insert(Item::ArrayOfTables(ArrayOfTables::new()))
+            .as_array_of_tables()
+            .ok_or(Error::MalformedSources)?;
+
+        let mut table = Table::new();
+        if let Some(name) = index.name.as_ref() {
+            table.insert("name", toml_edit::value(name.to_string()));
+        } else if let Some(name) = existing
+            .iter()
+            .find(|table| {
+                table
+                    .get("url")
+                    .is_some_and(|url| url.as_str() == Some(index.url.url().as_str()))
+            })
+            .and_then(|existing| existing.get("name"))
+        {
+            // If there's an existing index with the same URL, and a name, preserve the name.
+            table.insert("name", name.clone());
+        }
+        table.insert("url", toml_edit::value(index.url.to_string()));
+        if index.default {
+            table.insert("default", toml_edit::value(true));
+        }
+
+        // Push the item to the table.
+        let mut updated = ArrayOfTables::new();
+        updated.push(table);
+        for table in existing {
+            // If there's another index with the same name, replace it.
+            if table
+                .get("name")
+                .is_some_and(|name| name.as_str() == index.name.as_deref())
+            {
+                continue;
+            }
+
+            // If there's another default index, remove it.
+            if index.default
+                && table
+                    .get("default")
+                    .is_some_and(|default| default.as_bool() == Some(true))
+            {
+                continue;
+            }
+
+            // If there's another index with the same URL, replace it.
+            if table
+                .get("url")
+                .is_some_and(|url| url.as_str() == Some(index.url.url().as_str()))
+            {
+                continue;
+            }
+
+            updated.push(table.clone());
+        }
+        self.doc
+            .entry("tool")
+            .or_insert(implicit())
+            .as_table_mut()
+            .ok_or(Error::MalformedSources)?
+            .entry("uv")
+            .or_insert(implicit())
+            .as_table_mut()
+            .ok_or(Error::MalformedSources)?
+            .insert("index", Item::ArrayOfTables(updated));
+
+        Ok(())
+    }
+
     /// Adds a dependency to `project.optional-dependencies`.
     ///
     /// Returns `true` if the dependency was added, `false` if it was updated.

crates/uv/src/commands/project/add.rs

@@ -18,7 +18,7 @@ use uv_configuration::{
 };
 use uv_dispatch::BuildDispatch;
 use uv_distribution::DistributionDatabase;
-use uv_distribution_types::{UnresolvedRequirement, VersionId};
+use uv_distribution_types::{Index, UnresolvedRequirement, VersionId};
 use uv_fs::Simplified;
 use uv_git::{GitReference, GIT_STORE};
 use uv_normalize::PackageName;
@@ -59,6 +59,7 @@ pub(crate) async fn add(
     editable: Option<bool>,
     dependency_type: DependencyType,
     raw_sources: bool,
+    indexes: Vec<Index>,
     rev: Option<String>,
     tag: Option<String>,
     branch: Option<String>,
@@ -487,6 +488,13 @@ pub(crate) async fn add(
         });
     }
 
+    // Add any indexes that were provided on the command-line.
+    if !raw_sources {
+        for index in indexes {
+            toml.add_index(&index)?;
+        }
+    }
+
     let content = toml.to_string();
 
     // Save the modified `pyproject.toml` or script.

crates/uv/src/lib.rs

@@ -1380,6 +1380,7 @@ async fn run_project(
                 args.editable,
                 args.dependency_type,
                 args.raw_sources,
+                args.indexes,
                 args.rev,
                 args.tag,
                 args.branch,

crates/uv/src/settings.rs

@@ -809,6 +809,7 @@ pub(crate) struct AddSettings {
     pub(crate) script: Option<PathBuf>,
     pub(crate) python: Option<String>,
     pub(crate) refresh: Refresh,
+    pub(crate) indexes: Vec<Index>,
     pub(crate) settings: ResolverInstallerSettings,
 }
 
@@ -847,6 +848,51 @@ impl AddSettings {
             DependencyType::Production
         };
 
+        // Track the `--index` and `--default-index` arguments from the command-line.
+        let indexes = installer
+            .index_args
+            .default_index
+            .clone()
+            .and_then(Maybe::into_option)
+            .into_iter()
+            .chain(
+                installer
+                    .index_args
+                    .index
+                    .clone()
+                    .into_iter()
+                    .flatten()
+                    .filter_map(Maybe::into_option),
+            )
+            .collect::<Vec<_>>();
+
+        // If the user passed an `--index-url` or `--extra-index-url`, warn.
+        if installer
+            .index_args
+            .index_url
+            .as_ref()
+            .is_some_and(Maybe::is_some)
+        {
+            if script.is_some() {
+                warn_user_once!("Indexes specified via `--index-url` will not be persisted to the script; use `--default-index` instead.");
+            } else {
+                warn_user_once!("Indexes specified via `--index-url` will not be persisted to the `pyproject.toml` file; use `--default-index` instead.");
+            }
+        }
+
+        if installer
+            .index_args
+            .extra_index_url
+            .as_ref()
+            .is_some_and(|extra_index_url| extra_index_url.iter().any(Maybe::is_some))
+        {
+            if script.is_some() {
+                warn_user_once!("Indexes specified via `--extra-index-url` will not be persisted to the script; use `--index` instead.");
+            } else {
+                warn_user_once!("Indexes specified via `--extra-index-url` will not be persisted to the `pyproject.toml` file; use `--index` instead.");
+            }
+        }
+
         Self {
             locked,
             frozen,
@@ -864,6 +910,7 @@ impl AddSettings {
             editable: flag(editable, no_editable),
             extras: extra.unwrap_or_default(),
             refresh: Refresh::from(refresh),
+            indexes,
             settings: ResolverInstallerSettings::combine(
                 resolver_installer_options(installer, build),
                 filesystem,