Rollup merge of #98799 - jyn514:rustdoc-lint-help, r=GuillaumeGomez

Fix bug in `rustdoc -Whelp`

Previously, this printed the debugging options, not the lint options,
and only handled `-Whelp`, not `-A/-D/-F`.

This also fixes a few other misc issues:
- Fix `// check-stdout` for UI tests; previously it only worked for run-fail and compile-fail tests
- Add lint headers for tool lints, not just builtin lints

#98533 (comment)

r? ```@GuillaumeGomez```

Author: RalfJung

compiler/rustc_driver/src/lib.rs

@@ -849,10 +849,10 @@ Available lint options:
     };
 
     println!("Lint checks provided by rustc:\n");
-    println!("    {}  {:7.7}  {}", padded("name"), "default", "meaning");
-    println!("    {}  {:7.7}  {}", padded("----"), "-------", "-------");
 
     let print_lints = |lints: Vec<&Lint>| {
+        println!("    {}  {:7.7}  {}", padded("name"), "default", "meaning");
+        println!("    {}  {:7.7}  {}", padded("----"), "-------", "-------");
         for lint in lints {
             let name = lint.name_lower().replace('_', "-");
             println!(
@@ -884,11 +884,15 @@ Available lint options:
     };
 
     println!("Lint groups provided by rustc:\n");
-    println!("    {}  sub-lints", padded("name"));
-    println!("    {}  ---------", padded("----"));
-    println!("    {}  all lints that are set to issue warnings", padded("warnings"));
 
-    let print_lint_groups = |lints: Vec<(&'static str, Vec<LintId>)>| {
+    let print_lint_groups = |lints: Vec<(&'static str, Vec<LintId>)>, all_warnings| {
+        println!("    {}  sub-lints", padded("name"));
+        println!("    {}  ---------", padded("----"));
+
+        if all_warnings {
+            println!("    {}  all lints that are set to issue warnings", padded("warnings"));
+        }
+
         for (name, to) in lints {
             let name = name.to_lowercase().replace('_', "-");
             let desc = to
@@ -901,7 +905,7 @@ Available lint options:
         println!("\n");
     };
 
-    print_lint_groups(builtin_groups);
+    print_lint_groups(builtin_groups, true);
 
     match (loaded_plugins, plugin.len(), plugin_groups.len()) {
         (false, 0, _) | (false, _, 0) => {
@@ -916,7 +920,7 @@ Available lint options:
             }
             if g > 0 {
                 println!("Lint groups provided by plugins loaded by this crate:\n");
-                print_lint_groups(plugin_groups);
+                print_lint_groups(plugin_groups, false);
             }
         }
     }

src/librustdoc/config.rs

@@ -353,11 +353,7 @@ impl Options {
             print_flag_list("-C", config::CG_OPTIONS);
             return Err(0);
         }
-        let w_flags = matches.opt_strs("W");
-        if w_flags.iter().any(|x| *x == "help") {
-            print_flag_list("-W", config::DB_OPTIONS);
-            return Err(0);
-        }
+
         if matches.opt_strs("passes") == ["list"] {
             println!("Available passes for running rustdoc:");
             for pass in passes::PASSES {
@@ -439,15 +435,19 @@ impl Options {
             return Err(0);
         }
 
-        if matches.free.is_empty() {
+        let (lint_opts, describe_lints, lint_cap) = get_cmd_lint_options(matches, error_format);
+
+        let input = PathBuf::from(if describe_lints {
+            "" // dummy, this won't be used
+        } else if matches.free.is_empty() {
             diag.struct_err("missing file operand").emit();
             return Err(1);
-        }
-        if matches.free.len() > 1 {
+        } else if matches.free.len() > 1 {
             diag.struct_err("too many file operands").emit();
             return Err(1);
-        }
-        let input = PathBuf::from(&matches.free[0]);
+        } else {
+            &matches.free[0]
+        });
 
         let libs = matches
             .opt_strs("L")
@@ -698,8 +698,6 @@ impl Options {
         let with_examples = matches.opt_strs("with-examples");
         let call_locations = crate::scrape_examples::load_call_locations(with_examples, &diag)?;
 
-        let (lint_opts, describe_lints, lint_cap) = get_cmd_lint_options(matches, error_format);
-
         Ok(Options {
             input,
             proc_macro_crate,

src/librustdoc/lib.rs

@@ -75,7 +75,7 @@ use std::env::{self, VarError};
 use std::io;
 use std::process;
 
-use rustc_driver::{abort_on_err, describe_lints};
+use rustc_driver::abort_on_err;
 use rustc_errors::ErrorGuaranteed;
 use rustc_interface::interface;
 use rustc_middle::ty::TyCtxt;
@@ -770,15 +770,24 @@ fn main_options(options: config::Options) -> MainResult {
     let config = core::create_config(options);
 
     interface::create_compiler_and_run(config, |compiler| {
-        compiler.enter(|queries| {
-            let sess = compiler.session();
+        let sess = compiler.session();
 
-            if sess.opts.describe_lints {
-                let (_, lint_store) = &*queries.register_plugins()?.peek();
-                describe_lints(sess, lint_store, true);
-                return Ok(());
-            }
+        if sess.opts.describe_lints {
+            let mut lint_store = rustc_lint::new_lint_store(
+                sess.opts.debugging_opts.no_interleave_lints,
+                sess.unstable_options(),
+            );
+            let registered_lints = if let Some(register_lints) = compiler.register_lints() {
+                register_lints(sess, &mut lint_store);
+                true
+            } else {
+                false
+            };
+            rustc_driver::describe_lints(sess, &lint_store, registered_lints);
+            return Ok(());
+        }
 
+        compiler.enter(|queries| {
             // We need to hold on to the complete resolver, so we cause everything to be
             // cloned for the analysis passes to use. Suboptimal, but necessary in the
             // current architecture.