uv init should not create nested workspace (#5293)

## Summary

Resolves #5251

crates/uv-workspace/src/workspace.rs

@@ -62,6 +62,8 @@ pub struct Workspace {
     ///
     /// This table is overridden by the project sources.
     sources: BTreeMap<PackageName, Source>,
+    /// The `pyproject.toml` of the workspace root.
+    pyproject_toml: PyProjectToml,
 }
 
 impl Workspace {
@@ -323,6 +325,11 @@ impl Workspace {
         &self.sources
     }
 
+    /// The `pyproject.toml` of the workspace.
+    pub fn pyproject_toml(&self) -> &PyProjectToml {
+        &self.pyproject_toml
+    }
+
     /// Collect the workspace member projects from the `members` and `excludes` entries.
     async fn collect_members(
         workspace_root: PathBuf,
@@ -440,6 +447,7 @@ impl Workspace {
         }
         let workspace_sources = workspace_pyproject_toml
             .tool
+            .clone()
             .and_then(|tool| tool.uv)
             .and_then(|uv| uv.sources)
             .unwrap_or_default();
@@ -451,6 +459,7 @@ impl Workspace {
             lock_path,
             packages: workspace_members,
             sources: workspace_sources,
+            pyproject_toml: workspace_pyproject_toml,
         })
     }
 }
@@ -753,6 +762,7 @@ impl ProjectWorkspace {
                     // There may be package sources, but we don't need to duplicate them into the
                     // workspace sources.
                     sources: BTreeMap::default(),
+                    pyproject_toml: project_pyproject_toml.clone(),
                 },
             });
         };
@@ -1150,7 +1160,15 @@ mod tests {
                 "pyproject_toml": "[PYPROJECT_TOML]"
               }
             },
-            "sources": {}
+            "sources": {},
+            "pyproject_toml": {
+              "project": {
+                "name": "bird-feeder",
+                "requires-python": ">=3.12",
+                "optional-dependencies": null
+              },
+              "tool": null
+            }
           }
         }
         "###);
@@ -1186,7 +1204,15 @@ mod tests {
                     "pyproject_toml": "[PYPROJECT_TOML]"
                   }
                 },
-                "sources": {}
+                "sources": {},
+                "pyproject_toml": {
+                  "project": {
+                    "name": "bird-feeder",
+                    "requires-python": ">=3.12",
+                    "optional-dependencies": null
+                  },
+                  "tool": null
+                }
               }
             }
             "###);
@@ -1244,6 +1270,33 @@ mod tests {
                     "workspace": true,
                     "editable": null
                   }
+                },
+                "pyproject_toml": {
+                  "project": {
+                    "name": "albatross",
+                    "requires-python": ">=3.12",
+                    "optional-dependencies": null
+                  },
+                  "tool": {
+                    "uv": {
+                      "sources": {
+                        "bird-feeder": {
+                          "workspace": true,
+                          "editable": null
+                        }
+                      },
+                      "workspace": {
+                        "members": [
+                          "packages/*"
+                        ],
+                        "exclude": null
+                      },
+                      "managed": null,
+                      "dev-dependencies": null,
+                      "override-dependencies": null,
+                      "constraint-dependencies": null
+                    }
+                  }
                 }
               }
             }
@@ -1298,7 +1351,25 @@ mod tests {
                     "pyproject_toml": "[PYPROJECT_TOML]"
                   }
                 },
-                "sources": {}
+                "sources": {},
+                "pyproject_toml": {
+                  "project": null,
+                  "tool": {
+                    "uv": {
+                      "sources": null,
+                      "workspace": {
+                        "members": [
+                          "packages/*"
+                        ],
+                        "exclude": null
+                      },
+                      "managed": null,
+                      "dev-dependencies": null,
+                      "override-dependencies": null,
+                      "constraint-dependencies": null
+                    }
+                  }
+                }
               }
             }
             "###);
@@ -1333,7 +1404,15 @@ mod tests {
                     "pyproject_toml": "[PYPROJECT_TOML]"
                   }
                 },
-                "sources": {}
+                "sources": {},
+                "pyproject_toml": {
+                  "project": {
+                    "name": "albatross",
+                    "requires-python": ">=3.12",
+                    "optional-dependencies": null
+                  },
+                  "tool": null
+                }
               }
             }
             "###);

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

@@ -3,12 +3,13 @@ use std::path::PathBuf;
 
 use anyhow::Result;
 use owo_colors::OwoColorize;
+
 use pep508_rs::PackageName;
 use uv_configuration::PreviewMode;
 use uv_fs::Simplified;
 use uv_warnings::warn_user_once;
 use uv_workspace::pyproject_mut::PyProjectTomlMut;
-use uv_workspace::{ProjectWorkspace, WorkspaceError};
+use uv_workspace::{Workspace, WorkspaceError};
 
 use crate::commands::ExitStatus;
 use crate::printer::Printer;
@@ -53,7 +54,7 @@ pub(crate) async fn init(
             .unwrap_or_else(|_| path.simplified().to_path_buf());
 
         anyhow::bail!(
-            "Project is already initialized in {}",
+            "Project is already initialized in `{}`",
             path.display().cyan()
         );
     }
@@ -69,8 +70,9 @@ pub(crate) async fn init(
     let workspace = if isolated {
         None
     } else {
-        match ProjectWorkspace::discover(&path, None).await {
+        // Attempt to find a workspace root.
-            Ok(project) => Some(project),
+        match Workspace::discover(&path, None).await {
+            Ok(workspace) => Some(workspace),
             Err(WorkspaceError::MissingPyprojectToml) => None,
             Err(err) => return Err(err.into()),
         }
@@ -114,25 +116,20 @@ pub(crate) async fn init(
 
     if let Some(workspace) = workspace {
         // Add the package to the workspace.
-        let mut pyproject =
+        let mut pyproject = PyProjectTomlMut::from_toml(workspace.pyproject_toml())?;
-            PyProjectTomlMut::from_toml(workspace.current_project().pyproject_toml())?;
+        pyproject.add_workspace(path.strip_prefix(workspace.install_path())?)?;
-        pyproject.add_workspace(path.strip_prefix(workspace.project_root())?)?;
 
         // Save the modified `pyproject.toml`.
         fs_err::write(
-            workspace.current_project().root().join("pyproject.toml"),
+            workspace.install_path().join("pyproject.toml"),
             pyproject.to_string(),
         )?;
 
         writeln!(
             printer.stderr(),
-            "Adding {} as member of workspace {}",
+            "Adding `{}` as member of workspace `{}`",
             name.cyan(),
-            workspace
+            workspace.install_path().simplified_display().cyan()
-                .workspace()
-                .install_path()
-                .simplified_display()
-                .cyan()
         )?;
     }
 

crates/uv/tests/init.rs

@@ -200,7 +200,7 @@ fn init_workspace() -> Result<()> {
 
     ----- stderr -----
     warning: `uv init` is experimental and may change without warning
-    Adding foo as member of workspace [TEMP_DIR]/
+    Adding `foo` as member of workspace `[TEMP_DIR]/`
     Initialized project `foo`
     "###);
 
@@ -295,7 +295,7 @@ fn init_workspace_relative_sub_package() -> Result<()> {
 
     ----- stderr -----
     warning: `uv init` is experimental and may change without warning
-    Adding foo as member of workspace [TEMP_DIR]/
+    Adding `foo` as member of workspace `[TEMP_DIR]/`
     Initialized project `foo` at `[TEMP_DIR]/foo`
     "###);
 
@@ -391,7 +391,7 @@ fn init_workspace_outside() -> Result<()> {
 
     ----- stderr -----
     warning: `uv init` is experimental and may change without warning
-    Adding foo as member of workspace [TEMP_DIR]/
+    Adding `foo` as member of workspace `[TEMP_DIR]/`
     Initialized project `foo` at `[TEMP_DIR]/foo`
     "###);
 
@@ -556,3 +556,171 @@ fn init_workspace_isolated() -> Result<()> {
 
     Ok(())
 }
+
+#[test]
+fn init_nested_workspace() -> Result<()> {
+    let context = TestContext::new("3.12");
+
+    let pyproject_toml = context.temp_dir.child("pyproject.toml");
+    pyproject_toml.write_str(indoc! {
+        r#"
+        [project]
+        name = "project"
+        version = "0.1.0"
+        requires-python = ">=3.12"
+        "#,
+    })?;
+
+    // Create a child from the workspace root.
+    let child = context.temp_dir.join("foo");
+    uv_snapshot!(context.filters(), context.init().current_dir(&context.temp_dir).arg(&child), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    warning: `uv init` is experimental and may change without warning
+    Adding `foo` as member of workspace `[TEMP_DIR]/`
+    Initialized project `foo` at `[TEMP_DIR]/foo`
+    "###);
+
+    // Create a grandchild from the child directory.
+    uv_snapshot!(context.filters(), context.init().current_dir(&child).arg("bar"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    warning: `uv init` is experimental and may change without warning
+    Adding `bar` as member of workspace `[TEMP_DIR]/`
+    Initialized project `bar` at `[TEMP_DIR]/foo/bar`
+    "###);
+
+    let workspace = fs_err::read_to_string(pyproject_toml)?;
+    insta::with_settings!({
+        filters => context.filters(),
+    }, {
+        assert_snapshot!(
+            workspace, @r###"
+        [project]
+        name = "project"
+        version = "0.1.0"
+        requires-python = ">=3.12"
+
+        [tool.uv.workspace]
+        members = ["foo", "foo/bar"]
+        "###
+        );
+    });
+
+    let pyproject = fs_err::read_to_string(child.join("pyproject.toml"))?;
+    insta::with_settings!({
+        filters => context.filters(),
+    }, {
+        assert_snapshot!(
+            pyproject, @r###"
+        [project]
+        name = "foo"
+        version = "0.1.0"
+        description = "Add your description here"
+        readme = "README.md"
+        dependencies = []
+
+        [tool.uv]
+        dev-dependencies = []
+        "###
+        );
+    });
+
+    Ok(())
+}
+
+/// Run `uv init` from within a workspace with an explicit root.
+#[test]
+fn init_explicit_workspace() -> Result<()> {
+    let context = TestContext::new("3.12");
+
+    let pyproject_toml = context.temp_dir.child("pyproject.toml");
+    pyproject_toml.write_str(indoc! {
+        r#"
+        [project]
+        name = "project"
+        version = "0.1.0"
+        requires-python = ">=3.12"
+
+        [tool.uv.workspace]
+        members = []
+        "#,
+    })?;
+
+    let child = context.temp_dir.join("foo");
+    uv_snapshot!(context.filters(), context.init().current_dir(&context.temp_dir).arg(&child), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    warning: `uv init` is experimental and may change without warning
+    Adding `foo` as member of workspace `[TEMP_DIR]/`
+    Initialized project `foo` at `[TEMP_DIR]/foo`
+    "###);
+
+    let workspace = fs_err::read_to_string(context.temp_dir.join("pyproject.toml"))?;
+    insta::with_settings!({
+        filters => context.filters(),
+    }, {
+        assert_snapshot!(
+            workspace, @r###"
+        [project]
+        name = "project"
+        version = "0.1.0"
+        requires-python = ">=3.12"
+
+        [tool.uv.workspace]
+        members = ["foo"]
+        "###
+        );
+    });
+
+    Ok(())
+}
+
+/// Run `uv init` from within a virtual workspace.
+#[test]
+fn init_virtual_workspace() -> Result<()> {
+    let context = TestContext::new("3.12");
+
+    let pyproject_toml = context.temp_dir.child("pyproject.toml");
+    pyproject_toml.write_str(indoc! {
+        r"
+        [tool.uv.workspace]
+        members = []
+        ",
+    })?;
+
+    let child = context.temp_dir.join("foo");
+    uv_snapshot!(context.filters(), context.init().current_dir(&context.temp_dir).arg(&child), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    warning: `uv init` is experimental and may change without warning
+    Adding `foo` as member of workspace `[TEMP_DIR]/`
+    Initialized project `foo` at `[TEMP_DIR]/foo`
+    "###);
+
+    let workspace = fs_err::read_to_string(context.temp_dir.join("pyproject.toml"))?;
+    insta::with_settings!({
+        filters => context.filters(),
+    }, {
+        assert_snapshot!(
+            workspace, @r###"
+        [tool.uv.workspace]
+        members = ["foo"]
+        "###
+        );
+    });
+
+    Ok(())
+}