Generate API reference for options documentation (#5072)

## Summary

Generates Markdown from the `OptionsMetadata`, following the same
strategy as in Ruff.

## Test Plan

`cargo dev generate-options-reference`

crates/uv-dev/src/generate_json_schema.rs

@@ -6,7 +6,8 @@ use pretty_assertions::StrComparison;
 use schemars::{schema_for, JsonSchema};
 use serde::Deserialize;
 
-use uv_settings::Options;
+use uv_distribution::pyproject::ToolUv as WorkspaceOptions;
+use uv_settings::Options as SettingsOptions;
 
 use crate::ROOT_DIR;
 
@@ -16,11 +17,11 @@ use crate::ROOT_DIR;
 // The names and docstrings of this struct and the types it contains are used as `title` and
 // `description` in uv.schema.json, see https://github.com/SchemaStore/schemastore/blob/master/editor-features.md#title-as-an-expected-object-type
 /// Metadata and configuration for uv.
-struct ToolUv {
+struct CombinedOptions {
     #[serde(flatten)]
-    options: Options,
+    options: SettingsOptions,
     #[serde(flatten)]
-    dep_spec: uv_distribution::pyproject::ToolUv,
+    workspace: WorkspaceOptions,
 }
 
 #[derive(clap::Args)]
@@ -44,7 +45,7 @@ enum Mode {
 }
 
 pub(crate) fn main(args: &GenerateJsonSchemaArgs) -> Result<()> {
-    let schema = schema_for!(ToolUv);
+    let schema = schema_for!(CombinedOptions);
     let schema_string = serde_json::to_string_pretty(&schema).unwrap();
     let filename = "uv.schema.json";
     let schema_path = PathBuf::from(ROOT_DIR).join(filename);

crates/uv-dev/src/generate_options_reference.rs

@@ -0,0 +1,221 @@
+//! Generate a Markdown-compatible listing of configuration options for `pyproject.toml`.
+//!
+//! Based on: <https://github.com/astral-sh/ruff/blob/dc8db1afb08704ad6a788c497068b01edf8b460d/crates/ruff_dev/src/generate_options.rs>
+use std::fmt::Write;
+
+use itertools::Itertools;
+use schemars::JsonSchema;
+use serde::Deserialize;
+
+use uv_distribution::pyproject::ToolUv as WorkspaceOptions;
+use uv_macros::OptionsMetadata;
+use uv_options_metadata::{OptionField, OptionSet, OptionsMetadata, Visit};
+use uv_settings::Options as SettingsOptions;
+
+#[derive(Deserialize, JsonSchema, OptionsMetadata)]
+#[serde(deny_unknown_fields)]
+#[allow(dead_code)]
+// The names and docstrings of this struct and the types it contains are used as `title` and
+// `description` in uv.schema.json, see https://github.com/SchemaStore/schemastore/blob/master/editor-features.md#title-as-an-expected-object-type
+/// Metadata and configuration for uv.
+struct CombinedOptions {
+    #[serde(flatten)]
+    options: SettingsOptions,
+    #[serde(flatten)]
+    workspace: WorkspaceOptions,
+}
+
+pub(crate) fn generate() -> String {
+    let mut output = String::new();
+
+    generate_set(
+        &mut output,
+        Set::Global(CombinedOptions::metadata()),
+        &mut Vec::new(),
+    );
+
+    output
+}
+
+fn generate_set(output: &mut String, set: Set, parents: &mut Vec<Set>) {
+    match &set {
+        Set::Global(_) => {
+            output.push_str("### Global\n");
+        }
+        Set::Named { name, .. } => {
+            let title = parents
+                .iter()
+                .filter_map(|set| set.name())
+                .chain(std::iter::once(name.as_str()))
+                .join(".");
+            writeln!(output, "#### `{title}`\n").unwrap();
+
+            if let Some(documentation) = set.metadata().documentation() {
+                output.push_str(documentation);
+                output.push('\n');
+                output.push('\n');
+            }
+        }
+    }
+
+    let mut visitor = CollectOptionsVisitor::default();
+    set.metadata().record(&mut visitor);
+
+    let (mut fields, mut sets) = (visitor.fields, visitor.groups);
+
+    fields.sort_unstable_by(|(name, _), (name2, _)| name.cmp(name2));
+    sets.sort_unstable_by(|(name, _), (name2, _)| name.cmp(name2));
+
+    parents.push(set);
+
+    // Generate the fields.
+    for (name, field) in &fields {
+        emit_field(output, name, field, parents.as_slice());
+        output.push_str("---\n\n");
+    }
+
+    // Generate all the sub-sets.
+    for (set_name, sub_set) in &sets {
+        generate_set(
+            output,
+            Set::Named {
+                name: set_name.to_string(),
+                set: *sub_set,
+            },
+            parents,
+        );
+    }
+
+    parents.pop();
+}
+
+enum Set {
+    Global(OptionSet),
+    Named { name: String, set: OptionSet },
+}
+
+impl Set {
+    fn name(&self) -> Option<&str> {
+        match self {
+            Set::Global(_) => None,
+            Set::Named { name, .. } => Some(name),
+        }
+    }
+
+    fn metadata(&self) -> &OptionSet {
+        match self {
+            Set::Global(set) => set,
+            Set::Named { set, .. } => set,
+        }
+    }
+}
+
+fn emit_field(output: &mut String, name: &str, field: &OptionField, parents: &[Set]) {
+    let header_level = if parents.is_empty() { "####" } else { "#####" };
+    let parents_anchor = parents.iter().filter_map(|parent| parent.name()).join("_");
+
+    if parents_anchor.is_empty() {
+        output.push_str(&format!(
+            "{header_level} [`{name}`](#{name}) {{: #{name} }}\n"
+        ));
+    } else {
+        output.push_str(&format!(
+            "{header_level} [`{name}`](#{parents_anchor}_{name}) {{: #{parents_anchor}_{name} }}\n"
+        ));
+
+        // the anchor used to just be the name, but now it's the group name
+        // for backwards compatibility, we need to keep the old anchor
+        output.push_str(&format!("<span id=\"{name}\"></span>\n"));
+    }
+
+    output.push('\n');
+
+    if let Some(deprecated) = &field.deprecated {
+        output.push_str("!!! warning \"Deprecated\"\n");
+        output.push_str("    This option has been deprecated");
+
+        if let Some(since) = deprecated.since {
+            write!(output, " in {since}").unwrap();
+        }
+
+        output.push('.');
+
+        if let Some(message) = deprecated.message {
+            writeln!(output, " {message}").unwrap();
+        }
+
+        output.push('\n');
+    }
+
+    output.push_str(field.doc);
+    output.push_str("\n\n");
+    output.push_str(&format!("**Default value**: `{}`\n", field.default));
+    output.push('\n');
+    output.push_str(&format!("**Type**: `{}`\n", field.value_type));
+    output.push('\n');
+    output.push_str("**Example usage**:\n\n");
+    output.push_str(&format_tab(
+        "pyproject.toml",
+        &format_header(field.scope, parents, ConfigurationFile::PyprojectToml),
+        field.example,
+    ));
+    output.push_str(&format_tab(
+        "uv.toml",
+        &format_header(field.scope, parents, ConfigurationFile::UvToml),
+        field.example,
+    ));
+    output.push('\n');
+}
+
+fn format_tab(tab_name: &str, header: &str, content: &str) -> String {
+    format!(
+        "=== \"{}\"\n\n    ```toml\n    {}\n{}\n    ```\n",
+        tab_name,
+        header,
+        textwrap::indent(content, "    ")
+    )
+}
+
+/// Format the TOML header for the example usage for a given option.
+///
+/// For example: `[tool.uv.pip]`.
+fn format_header(scope: Option<&str>, parents: &[Set], configuration: ConfigurationFile) -> String {
+    let tool_parent = match configuration {
+        ConfigurationFile::PyprojectToml => Some("tool.uv"),
+        ConfigurationFile::UvToml => None,
+    };
+
+    let header = tool_parent
+        .into_iter()
+        .chain(parents.iter().filter_map(|parent| parent.name()))
+        .chain(scope)
+        .join(".");
+
+    if header.is_empty() {
+        String::new()
+    } else {
+        format!("[{header}]")
+    }
+}
+
+#[derive(Debug, Copy, Clone)]
+enum ConfigurationFile {
+    PyprojectToml,
+    UvToml,
+}
+
+#[derive(Default)]
+struct CollectOptionsVisitor {
+    groups: Vec<(String, OptionSet)>,
+    fields: Vec<(String, OptionField)>,
+}
+
+impl Visit for CollectOptionsVisitor {
+    fn record_set(&mut self, name: &str, group: OptionSet) {
+        self.groups.push((name.to_owned(), group));
+    }
+
+    fn record_field(&mut self, name: &str, field: OptionField) {
+        self.fields.push((name.to_owned(), field));
+    }
+}

crates/uv-dev/src/main.rs

@@ -44,6 +44,7 @@ mod build;
 mod clear_compile;
 mod compile;
 mod generate_json_schema;
+mod generate_options_reference;
 mod render_benchmarks;
 mod wheel_metadata;
 
@@ -61,6 +62,8 @@ enum Cli {
     ClearCompile(ClearCompileArgs),
     /// Generate JSON schema for the TOML configuration file.
     GenerateJSONSchema(GenerateJsonSchemaArgs),
+    /// Generate the options reference for the documentation.
+    GenerateOptionsReference,
     #[cfg(feature = "render")]
     /// Render the benchmarks.
     RenderBenchmarks(RenderBenchmarksArgs),
@@ -78,6 +81,7 @@ async fn run() -> Result<()> {
         Cli::Compile(args) => compile::compile(args).await?,
         Cli::ClearCompile(args) => clear_compile::clear_compile(&args)?,
         Cli::GenerateJSONSchema(args) => generate_json_schema::main(&args)?,
+        Cli::GenerateOptionsReference => println!("{}", generate_options_reference::generate()),
         #[cfg(feature = "render")]
         Cli::RenderBenchmarks(args) => render_benchmarks::render_benchmarks(&args)?,
     }