Store the registered lints in the Session

Author: Keegan McAllister

src/librustc/driver/driver.rs

@@ -79,8 +79,12 @@ pub fn compile_input(sess: Session,
                                                  &sess);
             let id = link::find_crate_id(krate.attrs.as_slice(),
                                          outputs.out_filestem.as_slice());
-            let (expanded_crate, ast_map) =
-                phase_2_configure_and_expand(&sess, krate, &id);
+            let (expanded_crate, ast_map)
+                = match phase_2_configure_and_expand(&sess, krate, &id) {
+                    None => return,
+                    Some(p) => p,
+                };
+
             (outputs, expanded_crate, ast_map)
         };
         write_out_deps(&sess, input, &outputs, &expanded_crate);
@@ -173,10 +177,12 @@ pub fn phase_1_parse_input(sess: &Session, cfg: ast::CrateConfig, input: &Input)
 /// syntax expansion, secondary `cfg` expansion, synthesis of a test
 /// harness if one is to be provided and injection of a dependency on the
 /// standard library and prelude.
+///
+/// Returns `None` if we're aborting after handling -W help.
 pub fn phase_2_configure_and_expand(sess: &Session,
                                     mut krate: ast::Crate,
                                     crate_id: &CrateId)
-                                    -> (ast::Crate, syntax::ast_map::Map) {
+                                    -> Option<(ast::Crate, syntax::ast_map::Map)> {
     let time_passes = sess.time_passes();
 
     *sess.crate_types.borrow_mut() = collect_crate_types(sess, krate.attrs.as_slice());
@@ -212,6 +218,17 @@ pub fn phase_2_configure_and_expand(sess: &Session,
 
     let Registry { syntax_exts, .. } = registry;
 
+    // Process command line flags for lints.
+    // Do this here because we will have lint plugins eventually.
+    if sess.opts.describe_lints {
+        super::describe_lints(&*sess.lint_store.borrow());
+        return None;
+    }
+    sess.lint_store.borrow_mut().process_command_line(sess);
+
+    // Abort if there are errors from lint processing or a plugin registrar.
+    sess.abort_if_errors();
+
     krate = time(time_passes, "expansion", (krate, macros, syntax_exts),
         |(krate, macros, syntax_exts)| {
             // Windows dlls do not have rpaths, so they don't know how to find their
@@ -254,7 +271,7 @@ pub fn phase_2_configure_and_expand(sess: &Session,
         krate.encode(&mut json).unwrap();
     }
 
-    (krate, map)
+    Some((krate, map))
 }
 
 pub struct CrateAnalysis {
@@ -631,9 +648,11 @@ pub fn pretty_print_input(sess: Session,
 
     let (krate, ast_map, is_expanded) = match ppm {
         PpmExpanded | PpmExpandedIdentified | PpmTyped | PpmFlowGraph(_) => {
-            let (krate, ast_map) = phase_2_configure_and_expand(&sess,
-                                                                krate,
-                                                                &id);
+            let (krate, ast_map)
+                = match phase_2_configure_and_expand(&sess, krate, &id) {
+                    None => return,
+                    Some(p) => p,
+                };
             (krate, Some(ast_map), true)
         }
         _ => (krate, None, false)

src/librustc/driver/mod.rs

@@ -13,6 +13,7 @@ pub use syntax::diagnostic;
 use back::link;
 use driver::driver::{Input, FileInput, StrInput};
 use driver::session::{Session, build_session};
+use lint::Lint;
 use lint;
 use metadata;
 
@@ -48,15 +49,18 @@ fn run_compiler(args: &[String]) {
         Some(matches) => matches,
         None => return
     };
-
     let sopts = config::build_session_options(&matches);
-    if sopts.describe_lints {
-        describe_lints();
-        return;
-    }
 
     let (input, input_file_path) = match matches.free.len() {
-        0u => early_error("no input filename given"),
+        0u => {
+            if sopts.describe_lints {
+                let mut ls = lint::LintStore::new();
+                ls.register_builtin(None);
+                describe_lints(&ls);
+                return;
+            }
+            early_error("no input filename given");
+        }
         1u => {
             let ifile = matches.free.get(0).as_slice();
             if ifile == "-" {
@@ -128,43 +132,56 @@ Additional help:
                              config::optgroups().as_slice()));
 }
 
-fn describe_lints() {
+fn describe_lints(lint_store: &lint::LintStore) {
     println!("
 Available lint options:
     -W <foo>           Warn about <foo>
     -A <foo>           Allow <foo>
     -D <foo>           Deny <foo>
     -F <foo>           Forbid <foo> (deny, and deny all overrides)
+
 ");
 
-    let mut builtin_specs = lint::builtin_lint_specs();
-    builtin_specs.sort_by(|x, y| {
-        match x.default_level.cmp(&y.default_level) {
-            Equal => x.name.cmp(&y.name),
-            r => r,
-        }
-    });
+    fn sort_lints(lints: Vec<(&'static Lint, bool)>) -> Vec<&'static Lint> {
+        let mut lints: Vec<_> = lints.move_iter().map(|(x, _)| x).collect();
+        lints.sort_by(|x: &&Lint, y: &&Lint| {
+            match x.default_level.cmp(&y.default_level) {
+                Equal => x.name.cmp(&y.name),
+                r => r,
+            }
+        });
+        lints
+    }
 
-    // FIXME: What if someone uses combining characters or East Asian fullwidth
-    // characters in a lint name?!?!?
-    let max_name_len = builtin_specs.iter()
+    let (_plugin, builtin) = lint_store.get_lints().partitioned(|&(_, p)| p);
+    // let plugin = sort_lints(plugin);
+    let builtin = sort_lints(builtin);
+
+    // FIXME (#7043): We should use the width in character cells rather than
+    // the number of codepoints.
+    let max_name_len = builtin.iter()
         .map(|&s| s.name.char_len())
         .max().unwrap_or(0);
     let padded = |x: &str| {
-        format!("{}{}", " ".repeat(max_name_len - x.char_len()), x)
+        " ".repeat(max_name_len - x.char_len()).append(x)
     };
 
-    println!("\nAvailable lint checks:\n");
+    println!("Lint checks provided by rustc:\n");
     println!("    {}  {:7.7s}  {}", padded("name"), "default", "meaning");
     println!("    {}  {:7.7s}  {}", padded("----"), "-------", "-------");
-    println!("");
 
-    for spec in builtin_specs.move_iter() {
-        let name = spec.name.replace("_", "-");
-        println!("    {}  {:7.7s}  {}",
-            padded(name.as_slice()), spec.default_level.as_str(), spec.desc);
-    }
-    println!("");
+    let print_lints = |lints: Vec<&Lint>| {
+        for lint in lints.move_iter() {
+            let name = lint.name.replace("_", "-");
+            println!("    {}  {:7.7s}  {}",
+                padded(name.as_slice()), lint.default_level.as_str(), lint.desc);
+        }
+        println!("\n");
+    };
+
+    print_lints(builtin);
+
+    // Describe lint plugins here once they exist.
 }
 
 fn describe_debug_flags() {

src/librustc/driver/session.rs

@@ -43,6 +43,7 @@ pub struct Session {
     // expected to be absolute. `None` means that there is no source file.
     pub local_crate_source_file: Option<Path>,
     pub working_dir: Path,
+    pub lint_store: RefCell<lint::LintStore>,
     pub lints: RefCell<NodeMap<Vec<(lint::LintId, codemap::Span, String)>>>,
     pub node_id: Cell<ast::NodeId>,
     pub crate_types: RefCell<Vec<config::CrateType>>,
@@ -226,7 +227,7 @@ pub fn build_session_(sopts: config::Options,
         }
     );
 
-    Session {
+    let sess = Session {
         targ_cfg: target_cfg,
         opts: sopts,
         cstore: CStore::new(token::get_ident_interner()),
@@ -238,12 +239,16 @@ pub fn build_session_(sopts: config::Options,
         default_sysroot: default_sysroot,
         local_crate_source_file: local_crate_source_file,
         working_dir: os::getcwd(),
+        lint_store: RefCell::new(lint::LintStore::new()),
         lints: RefCell::new(NodeMap::new()),
         node_id: Cell::new(1),
         crate_types: RefCell::new(Vec::new()),
         features: front::feature_gate::Features::new(),
         recursion_limit: Cell::new(64),
-    }
+    };
+
+    sess.lint_store.borrow_mut().register_builtin(Some(&sess));
+    sess
 }
 
 // Seems out of place, but it uses session, so I'm putting it here

src/librustc/lint/builtin.rs

@@ -1517,7 +1517,7 @@ impl LintPass for GatherNodeLevels {
         match it.node {
             ast::ItemEnum(..) => {
                 let lint_id = lint::LintId::of(variant_size_difference);
-                match cx.get_level_source(lint_id) {
+                match cx.lints.get_level_source(lint_id) {
                     lvlsrc @ (lvl, _) if lvl != lint::Allow => {
                         cx.insert_node_level(it.id, lint_id, lvlsrc);
                     },