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pnkfelix/lint.rs

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lint.rs
// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use driver::session;
use middle::ty;
use middle::pat_util;
use util::ppaux::{ty_to_str};
use std::cmp;
use std::hashmap::HashMap;
use std::i16;
use std::i32;
use std::i64;
use std::i8;
use std::u16;
use std::u32;
use std::u64;
use std::u8;
use extra::smallintmap::SmallIntMap;
use syntax::ast_map;
use syntax::attr;
use syntax::attr::AttrMetaMethods;
use syntax::codemap::span;
use syntax::codemap;
use syntax::parse::token;
use syntax::{ast, oldvisit, ast_util, visit};
use syntax::visit::{Visitor,fn_kind};
use syntax::ast::{expr,item,fn_decl,Block,NodeId,stmt,Local,TypeMethod};
use syntax::ast::{trait_method};
/**
* A 'lint' check is a kind of miscellaneous constraint that a user _might_
* want to enforce, but might reasonably want to permit as well, on a
* module-by-module basis. They contrast with static constraints enforced by
* other phases of the compiler, which are generally required to hold in order
* to compile the program at all.
*
* The lint checking is all consolidated into one pass which runs just before
* translation to LLVM bytecode. Throughout compilation, lint warnings can be
* added via the `add_lint` method on the Session structure. This requires a
* span and an id of the node that the lint is being added to. The lint isn't
* actually emitted at that time because it is unknown what the actual lint
* level at that location is.
*
* To actually emit lint warnings/errors, a separate pass is used just before
* translation. A context keeps track of the current state of all lint levels.
* Upon entering a node of the ast which can modify the lint settings, the
* previous lint state is pushed onto a stack and the ast is then recursed upon.
* As the ast is traversed, this keeps track of the current lint level for all
* lint attributes.
*
* At each node of the ast which can modify lint attributes, all known lint
* passes are also applied. Each lint pass is an oldvisit::vt<()> structure.
* The visitors are constructed via the lint_*() functions below. There are
* also some lint checks which operate directly on ast nodes (such as
* @ast::item), and those are organized as check_item_*(). Each visitor added
* to the lint context is modified to stop once it reaches a node which could
* alter the lint levels. This means that everything is looked at once and
* only once by every lint pass.
*
* With this all in place, to add a new lint warning, all you need to do is to
* either invoke `add_lint` on the session at the appropriate time, or write a
* lint pass in this module which is just an ast visitor. The context used when
* traversing the ast has a `span_lint` method which only needs the span of the
* item that's being warned about.
*/
#[deriving(Clone, Eq)]
pub enum lint {
ctypes,
unused_imports,
unnecessary_qualification,
while_true,
path_statement,
unrecognized_lint,
non_camel_case_types,
non_uppercase_statics,
type_limits,
unused_unsafe,
managed_heap_memory,
owned_heap_memory,
heap_memory,
unused_variable,
dead_assignment,
unused_mut,
unnecessary_allocation,
missing_doc,
unreachable_code,
warnings,
}
pub fn level_to_str(lv: level) -> &'static str {
match lv {
allow => "allow",
warn => "warn",
deny => "deny",
forbid => "forbid"
}
}
#[deriving(Clone, Eq, Ord)]
pub enum level {
allow, warn, deny, forbid
}
#[deriving(Clone, Eq)]
pub struct LintSpec {
lint: lint,
desc: &'static str,
default: level
}
impl Ord for LintSpec {
fn lt(&self, other: &LintSpec) -> bool { self.default < other.default }
}
pub type LintDict = HashMap<&'static str, LintSpec>;
enum AttributedNode<'self> {
Item(@ast::item),
Method(&'self ast::method),
Crate(@ast::Crate),
}
#[deriving(Eq)]
enum LintSource {
Node(span),
Default,
CommandLine
}
static lint_table: &'static [(&'static str, LintSpec)] = &[
("ctypes",
LintSpec {
lint: ctypes,
desc: "proper use of std::libc types in foreign modules",
default: warn
}),
("unused_imports",
LintSpec {
lint: unused_imports,
desc: "imports that are never used",
default: warn
}),
("unnecessary_qualification",
LintSpec {
lint: unnecessary_qualification,
desc: "detects unnecessarily qualified names",
default: allow
}),
("while_true",
LintSpec {
lint: while_true,
desc: "suggest using loop { } instead of while(true) { }",
default: warn
}),
("path_statement",
LintSpec {
lint: path_statement,
desc: "path statements with no effect",
default: warn
}),
("unrecognized_lint",
LintSpec {
lint: unrecognized_lint,
desc: "unrecognized lint attribute",
default: warn
}),
("non_camel_case_types",
LintSpec {
lint: non_camel_case_types,
desc: "types, variants and traits should have camel case names",
default: allow
}),
("non_uppercase_statics",
LintSpec {
lint: non_uppercase_statics,
desc: "static constants should have uppercase identifiers",
default: allow
}),
("managed_heap_memory",
LintSpec {
lint: managed_heap_memory,
desc: "use of managed (@ type) heap memory",
default: allow
}),
("owned_heap_memory",
LintSpec {
lint: owned_heap_memory,
desc: "use of owned (~ type) heap memory",
default: allow
}),
("heap_memory",
LintSpec {
lint: heap_memory,
desc: "use of any (~ type or @ type) heap memory",
default: allow
}),
("type_limits",
LintSpec {
lint: type_limits,
desc: "comparisons made useless by limits of the types involved",
default: warn
}),
("unused_unsafe",
LintSpec {
lint: unused_unsafe,
desc: "unnecessary use of an `unsafe` block",
default: warn
}),
("unused_variable",
LintSpec {
lint: unused_variable,
desc: "detect variables which are not used in any way",
default: warn
}),
("dead_assignment",
LintSpec {
lint: dead_assignment,
desc: "detect assignments that will never be read",
default: warn
}),
("unused_mut",
LintSpec {
lint: unused_mut,
desc: "detect mut variables which don't need to be mutable",
default: warn
}),
("unnecessary_allocation",
LintSpec {
lint: unnecessary_allocation,
desc: "detects unnecessary allocations that can be eliminated",
default: warn
}),
("missing_doc",
LintSpec {
lint: missing_doc,
desc: "detects missing documentation for public members",
default: allow
}),
("unreachable_code",
LintSpec {
lint: unreachable_code,
desc: "detects unreachable code",
default: warn
}),
("warnings",
LintSpec {
lint: warnings,
desc: "mass-change the level for lints which produce warnings",
default: warn
}),
];
/*
Pass names should not contain a '-', as the compiler normalizes
'-' to '_' in command-line flags
*/
pub fn get_lint_dict() -> LintDict {
let mut map = HashMap::new();
for &(k, v) in lint_table.iter() {
map.insert(k, v);
}
return map;
}
enum AnyVisitor {
// This is a pair so every visitor can visit every node. When a lint pass
// is registered, another visitor is created which stops at all items
// which can alter the attributes of the ast. This "item stopping visitor"
// is the second element of the pair, while the original visitor is the
// first element. This means that when visiting a node, the original
// recursive call can use the original visitor's method, although the
// recursing visitor supplied to the method is the item stopping visitor.
OldVisitor(@mut SubitemStoppableVisitor, @mut SubitemStoppableVisitor),
NewVisitor(@mut visit::Visitor<()>),
}
struct Context {
// All known lint modes (string versions)
dict: @LintDict,
// Current levels of each lint warning
curr: SmallIntMap<(level, LintSource)>,
// context we're checking in (used to access fields like sess)
tcx: ty::ctxt,
// Just a simple flag if we're currently recursing into a trait
// implementation. This is only used by the lint_missing_doc() pass
in_trait_impl: bool,
// Another flag for doc lint emissions. Does some parent of the current node
// have the doc(hidden) attribute? Treating this as allow(missing_doc) would
// play badly with forbid(missing_doc) when it shouldn't.
doc_hidden: bool,
// When recursing into an attributed node of the ast which modifies lint
// levels, this stack keeps track of the previous lint levels of whatever
// was modified.
lint_stack: ~[(lint, level, LintSource)],
// Each of these visitors represents a lint pass. A number of the lint
// attributes are registered by adding a visitor to iterate over the ast.
// Others operate directly on @ast::item structures (or similar). Finally,
// others still are added to the Session object via `add_lint`, and these
// are all passed with the lint_session visitor.
visitors: ~[AnyVisitor],
}
impl Context {
fn get_level(&self, lint: lint) -> level {
match self.curr.find(&(lint as uint)) {
Some(&(lvl, _)) => lvl,
None => allow
}
}
fn get_source(&self, lint: lint) -> LintSource {
match self.curr.find(&(lint as uint)) {
Some(&(_, src)) => src,
None => Default
}
}
fn set_level(&mut self, lint: lint, level: level, src: LintSource) {
if level == allow {
self.curr.remove(&(lint as uint));
} else {
self.curr.insert(lint as uint, (level, src));
}
}
fn lint_to_str(&self, lint: lint) -> &'static str {
for (k, v) in self.dict.iter() {
if v.lint == lint {
return *k;
}
}
fail!("unregistered lint %?", lint);
}
fn span_lint(&self, lint: lint, span: span, msg: &str) {
let (level, src) = match self.curr.find(&(lint as uint)) {
None => { return }
Some(&(warn, src)) => (self.get_level(warnings), src),
Some(&pair) => pair,
};
if level == allow { return }
let mut note = None;
let msg = match src {
Default | CommandLine => {
fmt!("%s [-%c %s%s]", msg, match level {
warn => 'W', deny => 'D', forbid => 'F',
allow => fail!()
}, self.lint_to_str(lint).replace("_", "-"),
if src == Default { " (default)" } else { "" })
},
Node(src) => {
note = Some(src);
msg.to_str()
}
};
match level {
warn => { self.tcx.sess.span_warn(span, msg); }
deny | forbid => { self.tcx.sess.span_err(span, msg); }
allow => fail!(),
}
for &span in note.iter() {
self.tcx.sess.span_note(span, "lint level defined here");
}
}
/**
* Merge the lints specified by any lint attributes into the
* current lint context, call the provided function, then reset the
* lints in effect to their previous state.
*/
fn with_lint_attrs(@mut self, attrs: &[ast::Attribute], f: &fn()) {
// Parse all of the lint attributes, and then add them all to the
// current dictionary of lint information. Along the way, keep a history
// of what we changed so we can roll everything back after invoking the
// specified closure
let mut pushed = 0u;
do each_lint(self.tcx.sess, attrs) |meta, level, lintname| {
match self.dict.find_equiv(&lintname) {
None => {
self.span_lint(
unrecognized_lint,
meta.span,
fmt!("unknown `%s` attribute: `%s`",
level_to_str(level), lintname));
}
Some(lint) => {
let lint = lint.lint;
let now = self.get_level(lint);
if now == forbid && level != forbid {
self.tcx.sess.span_err(meta.span,
fmt!("%s(%s) overruled by outer forbid(%s)",
level_to_str(level),
lintname, lintname));
} else if now != level {
let src = self.get_source(lint);
self.lint_stack.push((lint, now, src));
pushed += 1;
self.set_level(lint, level, Node(meta.span));
}
}
}
true
};
// detect doc(hidden)
let mut doc_hidden = do attrs.iter().any |attr| {
"doc" == attr.name() &&
match attr.meta_item_list() {
Some(l) => attr::contains_name(l, "hidden"),
None => false // not of the form #[doc(...)]
}
};
if doc_hidden && !self.doc_hidden {
self.doc_hidden = true;
} else {
doc_hidden = false;
}
f();
// rollback
if doc_hidden && self.doc_hidden {
self.doc_hidden = false;
}
do pushed.times {
let (lint, lvl, src) = self.lint_stack.pop();
self.set_level(lint, lvl, src);
}
}
fn add_oldvisit_lint<V:Clone+SubitemStoppableVisitor>(&mut self, v: @mut V) {
let v = OldVisitor(v.clone() as @mut SubitemStoppableVisitor,
item_stopping_visitor(v) as @mut SubitemStoppableVisitor);
self.visitors.push(v);
}
fn add_lint(&mut self, v: @mut visit::Visitor<()>) {
self.visitors.push(NewVisitor(v));
}
fn process(@mut self, n: AttributedNode) {
// see comment of the `visitors` field in the struct for why there's a
// pair instead of just one visitor.
match n {
Item(it) => {
for visitor in self.visitors.iter() {
match *visitor {
OldVisitor(orig, stopping) => {
orig.visit_item_action(it, self);
visit::walk_item(stopping as @mut Visitor<@mut Context>, it, self);
}
NewVisitor(new_visitor) => {
let mut new_visitor = new_visitor;
new_visitor.visit_item(it, ());
}
}
}
}
Crate(c) => {
for visitor in self.visitors.iter() {
match *visitor {
OldVisitor(_, stopping) => {
visit::walk_crate(stopping as @mut Visitor<@mut Contxt>, c, self)
}
NewVisitor(new_visitor) => {
let mut new_visitor = new_visitor;
visit::walk_crate(&mut new_visitor, c, ())
}
}
}
}
// Can't use oldvisit::visit_method_helper because the
// item_stopping_visitor has overridden visit_fn(&fk_method(... ))
// to be a no-op, so manually invoke visit_fn.
Method(m) => {
for visitor in self.visitors.iter() {
match *visitor {
OldVisitor(orig, stopping) => {
let fk = ast::fk_method(m.ident,
&m.generics,
m);
orig.visit_fn_action(&fk,
&m.decl,
&m.body,
m.span,
m.id,
self);
visit::walk_fn(stopping, &fk,
&m.decl,
&m.body,
m.span,
m.id,
self);
}
NewVisitor(new_visitor) => {
let fk = ast::fk_method(m.ident,
&m.generics,
m);
let mut new_visitor = new_visitor;
new_visitor.visit_fn(&fk,
&m.decl,
&m.body,
m.span,
m.id,
())
}
}
}
}
}
}
}
pub fn each_lint(sess: session::Session,
attrs: &[ast::Attribute],
f: &fn(@ast::MetaItem, level, @str) -> bool) -> bool {
let xs = [allow, warn, deny, forbid];
for &level in xs.iter() {
let level_name = level_to_str(level);
for attr in attrs.iter().filter(|m| level_name == m.name()) {
let meta = attr.node.value;
let metas = match meta.node {
ast::MetaList(_, ref metas) => metas,
_ => {
sess.span_err(meta.span, "malformed lint attribute");
loop;
}
};
for meta in metas.iter() {
match meta.node {
ast::MetaWord(lintname) => {
if !f(*meta, level, lintname) {
return false;
}
}
_ => {
sess.span_err(meta.span, "malformed lint attribute");
}
}
}
}
}
true
}
trait SubitemStoppableVisitor : Visitor<@mut Context> {
fn item_stopped_variant() -> Self;
fn is_running_on_items(&mut self) -> bool;
fn visit_item_action(&mut self, i:@item, e:@mut Context) {
// fill in with particular action without recursion if desired
}
fn visit_fn_action(&mut self, fk:&fn_kind, fd:&fn_decl,
b:&Block, s:span, n:NodeId, e:@mut Context) {
// fill in with particular action without recursion if desired
}
fn OVERRIDE_visit_item(&mut self, i:@item, e:@mut Context) {
if self.is_running_on_items() {
self.visit_item_action(i, e);
visit::walk_item(self, i, e);
}
}
fn OVERRIDE_visit_fn(&mut self, fk:&fn_kind, fd:&fn_decl,
b:&Block, s:span, n:NodeId, e:@mut Context) {
if self.is_running_on_items() {
self.visit_fn_action(fk, fd, b, s, n, e);
visit::walk_fn(self, fk, fd, b, s, n, e);
}
}
}
// Take a visitor, and modify it so that it will not proceed past subitems.
// This is used to make the simple visitors used for the lint passes
// not traverse into subitems, since that is handled by the outer
// lint visitor.
fn item_stopping_visitor<V:SubitemStoppableVisitor>(outer: @mut V) -> @mut V {
@mut outer.item_stopped_variant()
}
struct WhileTrueLintVisitor { stopping_on_items: bool }
impl SubitemStoppableVisitor for WhileTrueLintVisitor {
fn is_running_on_items(&mut self) -> bool { !self.stopping_on_items }
fn item_stopped_variant() -> WhileTrueLintVisitor {
WhileTrueLintVisitor { stopping_on_items: true }
}
}
impl Visitor<@mut Context> for WhileTrueLintVisitor {
fn visit_item(&mut self, i:@item, e:@mut Context) {
self.OVERRIDE_visit_item(i, e);
}
fn visit_fn(&mut self, fk:&fn_kind, fd:&fn_decl,
b:&Block, s:span, n:NodeId, e:@mut Context) {
self.OVERRIDE_visit_fn(fk, fd, b, s, n, e);
}
fn visit_expr(&mut self, e:@expr, cx:@mut Context) {
match e.node {
ast::expr_while(cond, _) => {
match cond.node {
ast::expr_lit(@codemap::spanned {
node: ast::lit_bool(true), _}) =>
{
cx.span_lint(while_true, e.span,
"denote infinite loops with \
loop { ... }");
}
_ => ()
}
}
_ => ()
}
visit::walk_expr(self, e, cx);
}
}
fn lint_while_true() -> WhileTrueLintVisitor {
WhileTrueLintVisitor{ stopping_on_items: false }
}
struct TypeLimitsLintVisitor;
impl Visitor<@mut Context> for TypeLimitsLintVisitor {
fn visit_expr(&mut self, e:@expr, cx:@mut Context) {
match e.node {
ast::expr_binary(_, ref binop, l, r) => {
if self.is_comparison(*binop)
&& !self.check_limits(cx, *binop, l, r) {
cx.span_lint(type_limits, e.span,
"comparison is useless due to type limits");
}
}
_ => ()
}
visit::walk_expr(self, e, cx);
}
}
impl TypeLimitsLintVisitor {
fn is_valid<T:cmp::Ord>(&mut self, binop: ast::binop, v: T,
min: T, max: T) -> bool {
match binop {
ast::lt => v <= max,
ast::le => v < max,
ast::gt => v >= min,
ast::ge => v > min,
ast::eq | ast::ne => v >= min && v <= max,
_ => fail!()
}
}
fn rev_binop(&mut self, binop: ast::binop) -> ast::binop {
match binop {
ast::lt => ast::gt,
ast::le => ast::ge,
ast::gt => ast::lt,
ast::ge => ast::le,
_ => binop
}
}
// for int & uint, be conservative with the warnings, so that the
// warnings are consistent between 32- and 64-bit platforms
fn int_ty_range(&mut self, int_ty: ast::int_ty) -> (i64, i64) {
match int_ty {
ast::ty_i => (i64::min_value, i64::max_value),
ast::ty_char => (u32::min_value as i64, u32::max_value as i64),
ast::ty_i8 => (i8::min_value as i64, i8::max_value as i64),
ast::ty_i16 => (i16::min_value as i64, i16::max_value as i64),
ast::ty_i32 => (i32::min_value as i64, i32::max_value as i64),
ast::ty_i64 => (i64::min_value, i64::max_value)
}
}
fn uint_ty_range(&mut self, uint_ty: ast::uint_ty) -> (u64, u64) {
match uint_ty {
ast::ty_u => (u64::min_value, u64::max_value),
ast::ty_u8 => (u8::min_value as u64, u8::max_value as u64),
ast::ty_u16 => (u16::min_value as u64, u16::max_value as u64),
ast::ty_u32 => (u32::min_value as u64, u32::max_value as u64),
ast::ty_u64 => (u64::min_value, u64::max_value)
}
}
fn check_limits(&mut self, cx: &Context,
binop: ast::binop,
l: @ast::expr,
r: @ast::expr)
-> bool {
let (lit, expr, swap) = match (&l.node, &r.node) {
(&ast::expr_lit(_), _) => (l, r, true),
(_, &ast::expr_lit(_)) => (r, l, false),
_ => return true
};
// Normalize the binop so that the literal is always on the RHS in
// the comparison
let norm_binop = if swap {
self.rev_binop(binop)
} else {
binop
};
match ty::get(ty::expr_ty(cx.tcx, expr)).sty {
ty::ty_int(int_ty) => {
let (min, max) = self.int_ty_range(int_ty);
let lit_val: i64 = match lit.node {
ast::expr_lit(@li) => match li.node {
ast::lit_int(v, _) => v,
ast::lit_uint(v, _) => v as i64,
ast::lit_int_unsuffixed(v) => v,
_ => return true
},
_ => fail!()
};
self.is_valid(norm_binop, lit_val, min, max)
}
ty::ty_uint(uint_ty) => {
let (min, max): (u64, u64) = self.uint_ty_range(uint_ty);
let lit_val: u64 = match lit.node {
ast::expr_lit(@li) => match li.node {
ast::lit_int(v, _) => v as u64,
ast::lit_uint(v, _) => v,
ast::lit_int_unsuffixed(v) => v as u64,
_ => return true
},
_ => fail!()
};
self.is_valid(norm_binop, lit_val, min, max)
}
_ => true
}
}
fn is_comparison(&mut self, binop: ast::binop) -> bool {
match binop {
ast::eq | ast::lt | ast::le |
ast::ne | ast::ge | ast::gt => true,
_ => false
}
}
}
fn lint_type_limits() -> TypeLimitsLintVisitor {
TypeLimitsLintVisitor
}
fn check_item_ctypes(cx: &Context, it: &ast::item) {
fn check_ty(cx: &Context, ty: &ast::Ty) {
match ty.node {
ast::ty_path(_, _, id) => {
match cx.tcx.def_map.get_copy(&id) {
ast::def_prim_ty(ast::ty_int(ast::ty_i)) => {
cx.span_lint(ctypes, ty.span,
"found rust type `int` in foreign module, while \
libc::c_int or libc::c_long should be used");
}
ast::def_prim_ty(ast::ty_uint(ast::ty_u)) => {
cx.span_lint(ctypes, ty.span,
"found rust type `uint` in foreign module, while \
libc::c_uint or libc::c_ulong should be used");
}
_ => ()
}
}
ast::ty_ptr(ref mt) => { check_ty(cx, mt.ty) }
_ => ()
}
}
fn check_foreign_fn(cx: &Context, decl: &ast::fn_decl) {
for input in decl.inputs.iter() {
check_ty(cx, &input.ty);
}
check_ty(cx, &decl.output)
}
match it.node {
ast::item_foreign_mod(ref nmod) if !nmod.abis.is_intrinsic() => {
for ni in nmod.items.iter() {
match ni.node {
ast::foreign_item_fn(ref decl, _) => {
check_foreign_fn(cx, decl);
}
ast::foreign_item_static(ref t, _) => { check_ty(cx, t); }
}
}
}
_ => {/* nothing to do */ }
}
}
fn check_type_for_lint(cx: &Context, lint: lint, span: span, ty: ty::t) {
if cx.get_level(lint) == allow { return }
let mut n_box = 0;
let mut n_uniq = 0;
ty::fold_ty(cx.tcx, ty, |t| {
match ty::get(t).sty {
ty::ty_box(_) => n_box += 1,
ty::ty_uniq(_) => n_uniq += 1,
_ => ()
};
t
});
if n_uniq > 0 && lint != managed_heap_memory {
let s = ty_to_str(cx.tcx, ty);
let m = ~"type uses owned (~ type) pointers: " + s;
cx.span_lint(lint, span, m);
}
if n_box > 0 && lint != owned_heap_memory {
let s = ty_to_str(cx.tcx, ty);
let m = ~"type uses managed (@ type) pointers: " + s;
cx.span_lint(lint, span, m);
}
}
fn check_type(cx: &Context, span: span, ty: ty::t) {
let xs = [managed_heap_memory, owned_heap_memory, heap_memory];
for lint in xs.iter() {
check_type_for_lint(cx, *lint, span, ty);
}
}
fn check_item_heap(cx: &Context, it: &ast::item) {
match it.node {
ast::item_fn(*) |
ast::item_ty(*) |
ast::item_enum(*) |
ast::item_struct(*) => check_type(cx, it.span,
ty::node_id_to_type(cx.tcx,
it.id)),
_ => ()
}
// If it's a struct, we also have to check the fields' types
match it.node {
ast::item_struct(struct_def, _) => {
for struct_field in struct_def.fields.iter() {
check_type(cx, struct_field.span,
ty::node_id_to_type(cx.tcx,
struct_field.node.id));
}
}
_ => ()
}
}
struct HeapLintVisitor { stopping_on_items: bool }
impl SubitemStoppableVisitor for HeapLintVisitor {
fn is_running_on_items(&mut self) -> bool { !self.stopping_on_items }
fn item_stopped_variant() -> HeapLintVisitor {
HeapLintVisitor { stopping_on_items: true }
}
}
impl Visitor<@mut Context> for HeapLintVisitor {
fn visit_item(&mut self, i:@item, e:@mut Context) {
self.OVERRIDE_visit_item(i, e);
}
fn visit_fn(&mut self, fk:&fn_kind, fd:&fn_decl,
b:&Block, s:span, n:NodeId, e:@mut Context) {
self.OVERRIDE_visit_fn(fk, fd, b, s, n, e);
}
fn visit_expr(&mut self, e:@expr, cx:@mut Context) {
let ty = ty::expr_ty(cx.tcx, e);
check_type(cx, e.span, ty);
visit::walk_expr(self, e, cx);
}
}
fn lint_heap() -> HeapLintVisitor {
HeapLintVisitor { stopping_on_items: false }
}
struct PathStatementLintVisitor {
stopping_on_items: bool
}
impl Visitor<@mut Context> for PathStatementLintVisitor {
fn visit_item(&mut self, i:@item, e:@mut Context) {
self.OVERRIDE_visit_item(i, e);
}
fn visit_fn(&mut self, fk:&fn_kind, fd:&fn_decl,
b:&Block, s:span, n:NodeId, e:@mut Context) {
self.OVERRIDE_visit_fn(fk, fd, b, s, n, e);
}
fn visit_stmt(&mut self, s:@stmt, cx:@mut Context) {
match s.node {
ast::stmt_semi(
@ast::expr { node: ast::expr_path(_), _ },
_
) => {
cx.span_lint(path_statement, s.span,
"path statement with no effect");
}
_ => ()
}
visit::walk_stmt(s, cx);
}
}
fn lint_path_statement() -> PathStatementLintVisitor {
PathStatementLintVisitor{ stopping_on_items: false }
}
fn check_item_non_camel_case_types(cx: &Context, it: &ast::item) {
fn is_camel_case(cx: ty::ctxt, ident: ast::ident) -> bool {
let ident = cx.sess.str_of(ident);
assert!(!ident.is_empty());
let ident = ident.trim_chars(&'_');
// start with a non-lowercase letter rather than non-uppercase
// ones (some scripts don't have a concept of upper/lowercase)
!ident.char_at(0).is_lowercase() &&
!ident.contains_char('_')
}
fn check_case(cx: &Context, sort: &str, ident: ast::ident, span: span) {
if !is_camel_case(cx.tcx, ident) {
cx.span_lint(
non_camel_case_types, span,
fmt!("%s `%s` should have a camel case identifier",
sort, cx.tcx.sess.str_of(ident)));
}
}
match it.node {
ast::item_ty(*) | ast::item_struct(*) => {
check_case(cx, "type", it.ident, it.span)
}
ast::item_trait(*) => {
check_case(cx, "trait", it.ident, it.span)
}
ast::item_enum(ref enum_definition, _) => {
check_case(cx, "type", it.ident, it.span);
for variant in enum_definition.variants.iter() {
check_case(cx, "variant", variant.node.name, variant.span);
}
}
_ => ()
}
}
fn check_item_non_uppercase_statics(cx: &Context, it: &ast::item) {
match it.node {
// only check static constants
ast::item_static(_, ast::m_imm, _) => {
let s = cx.tcx.sess.str_of(it.ident);
// check for lowercase letters rather than non-uppercase
// ones (some scripts don't have a concept of
// upper/lowercase)
if s.iter().any(|c| c.is_lowercase()) {
cx.span_lint(non_uppercase_statics, it.span,
"static constant should have an uppercase identifier");
}
}
_ => {}
}
}
struct UnusedUnsafeLintVisitor { stopping_on_items: bool }
impl SubitemStoppableVisitor for UnusedUnsafeLintVisitor {
fn is_running_on_items(&mut self) -> bool { !self.stopping_on_items }
fn item_stopped_variant() -> UnusedUnsafeLintVisitor {
UnusedUnsafeLintVisitor { stopping_on_items: true }
}
}
impl Visitor<@mut Context> for UnusedUnsafeLintVisitor {
fn visit_item(&mut self, i:@item, e:@mut Context) {
self.OVERRIDE_visit_item(i, e);
}
fn visit_fn(&mut self, fk:&fn_kind, fd:&fn_decl,
b:&Block, s:span, n:NodeId, e:@mut Context) {
self.OVERRIDE_visit_fn(fk, fd, b, s, n, e);
}
fn visit_expr(&mut self, e:@expr, cx:@mut Context) {
match e.node {
ast::expr_block(ref blk) if blk.rules == ast::UnsafeBlock => {
if !cx.tcx.used_unsafe.contains(&blk.id) {
cx.span_lint(unused_unsafe, blk.span,
"unnecessary `unsafe` block");
}
}
_ => ()
}
visit::walk_expr(e, cx);
}
}
fn lint_unused_unsafe() -> UnusedUnsafeLintVisitor {
UnusedUnsafeLintVisitor{ stopping_on_items: false }
}
struct UnusedMutLintVisitor { stopping_on_items: bool }
impl SubitemStoppableVisitor for UnusedMutLintVisitor {
fn item_stopped_variant() -> UnusedMutLintVisitor {
UnusedMutLintVisitor{ stopping_on_items: true }
}
fn is_running_on_items(&mut self) -> bool { !self.stopping_on_items }
fn visit_fn_action(&mut self, a:&fn_kind, fd:&fn_decl,
b:&Block, c:span, d:NodeId, cx:@mut Context) {
self.visit_fn_decl(cx, fd);
visit::walk_fn(self, a, fd, b, c, d, cx);
}
}
impl Visitor<@mut Context> for UnusedMutLintVisitor {
fn visit_local(&mut self, l:@Local, cx:@mut Context) {
if l.is_mutbl {
self.check_pat(cx, l.pat);
}
visit::walk_local(self, l, cx);
}
fn visit_item(&mut self, i:@item, e:@mut Context) {
self.OVERRIDE_visit_item(i, e);
}
fn visit_ty_method(&mut self, tm:&TypeMethod, cx:@mut Context) {
self.visit_fn_decl(cx, &tm.decl);
visit::walk_ty_method(self, tm, cx);
}
fn visit_trait_method(&mut self, tm:&trait_method, cx:@mut Context) {
match *tm {
ast::required(ref tm) => self.visit_fn_decl(cx, &tm.decl),
ast::provided(m) => self.visit_fn_decl(cx, &m.decl)
}
visit::walk_trait_method(self, tm, cx);
}
}
impl UnusedMutLintVisitor {
fn check_pat(&mut self, cx: &Context, p: @ast::pat) {
let mut used = false;
let mut bindings = 0;
do pat_util::pat_bindings(cx.tcx.def_map, p) |_, id, _, _| {
used = used || cx.tcx.used_mut_nodes.contains(&id);
bindings += 1;
}
if !used {
let msg = if bindings == 1 {
"variable does not need to be mutable"
} else {
"variables do not need to be mutable"
};
cx.span_lint(unused_mut, p.span, msg);
}
}
fn visit_fn_decl(&mut self, cx: &Context, fd: &ast::fn_decl) {
for arg in fd.inputs.iter() {
if arg.is_mutbl {
self.check_pat(cx, arg.pat);
}
}
}
}
fn lint_unused_mut() -> UnusedMutLintVisitor {
UnusedMutLintVisitor{ stopping_on_items: false }
}
fn lint_session(cx: @mut Context) -> @mut visit::Visitor<()> {
ast_util::id_visitor(|id| {
match cx.tcx.sess.lints.pop(&id) {
None => {},
Some(l) => {
for (lint, span, msg) in l.move_iter() {
cx.span_lint(lint, span, msg)
}
}
}
}, false)
}
struct UnnecessaryAllocationLintVisitor { stopping_on_items: bool }
impl SubitemStoppableVisitor for UnnecessaryAllocationLintVisitor {
fn is_running_on_items(&mut self) -> bool { !self.stopping_on_items }
fn item_stopped_variant() -> UnnecessaryAllocationLintVisitor {
UnnecessaryAllocationLintVisitor { stopping_on_items: true }
}
}
impl Visitor<@mut Context> for UnnecessaryAllocationLintVisitor {
fn visit_item(&mut self, i:@item, e:@mut Context) {
self.OVERRIDE_visit_item(i, e);
}
fn visit_fn(&mut self, fk:&fn_kind, fd:&fn_decl,
b:&Block, s:span, n:NodeId, e:@mut Context) {
self.OVERRIDE_visit_fn(fk, fd, b, s, n, e);
}
fn visit_expr(&mut self, e:@expr, cx:@mut Context) {
self.check(cx, e);
visit::walk_expr(self, e, cx);
}
}
impl UnnecessaryAllocationLintVisitor {
// Warn if string and vector literals with sigils are immediately borrowed.
// Those can have the sigil removed.
fn check(&mut self, cx: &Context, e: &ast::expr) {
match e.node {
ast::expr_vstore(e2, ast::expr_vstore_uniq) |
ast::expr_vstore(e2, ast::expr_vstore_box) => {
match e2.node {
ast::expr_lit(@codemap::spanned{
node: ast::lit_str(*), _}) |
ast::expr_vec(*) => {}
_ => return
}
}
_ => return
}
match cx.tcx.adjustments.find_copy(&e.id) {
Some(@ty::AutoDerefRef(ty::AutoDerefRef {
autoref: Some(ty::AutoBorrowVec(*)), _ })) => {
cx.span_lint(unnecessary_allocation,
e.span, "unnecessary allocation, the sigil can be \
removed");
}
_ => ()
}
}
}
fn lint_unnecessary_allocations() -> UnnecessaryAllocationLintVisitor {
UnnecessaryAllocationLintVisitor{ stopping_on_items: false }
}
struct MissingDocLintVisitor { stopping_on_items: bool }
impl SubitemStoppableVisitor for MissingDocLintVisitor {
fn is_running_on_items(&mut self) -> bool { !self.stopping_on_items }
fn item_stopped_variant() -> MissingDocLintVisitor {
MissingDocLintVisitor { stopping_on_items: true }
}
fn visit_fn_action(&mut self, fk:&fn_kind, d:&fn_decl,
b:&Block, sp:span, id:NodeId, cx:@mut Context) {
// Only warn about explicitly public methods. Soon implicit
// public-ness will hopefully be going away.
match *fk {
ast::fk_method(_, _, m) if m.vis == ast::public => {
// If we're in a trait implementation, no need to duplicate
// documentation
if !cx.in_trait_impl {
self.check_attrs(cx, m.attrs, sp,
"missing documentation for a method");
}
}
_ => {}
}
}
fn visit_item_action(&mut self, it:@item, cx:@mut Context) {
match it.node {
// Go ahead and match the fields here instead of using
// visit_struct_field while we have access to the enclosing
// struct's visibility
ast::item_struct(sdef, _) if it.vis == ast::public => {
self.check_attrs(cx, it.attrs, it.span,
"missing documentation for a struct");
for field in sdef.fields.iter() {
match field.node.kind {
ast::named_field(_, vis) if vis != ast::private => {
self.check_attrs(cx, field.node.attrs, field.span,
"missing documentation for a field");
}
ast::unnamed_field | ast::named_field(*) => {}
}
}
}
ast::item_trait(*) if it.vis == ast::public => {
self.check_attrs(cx, it.attrs, it.span,
"missing documentation for a trait");
}
ast::item_fn(*) if it.vis == ast::public => {
self.check_attrs(cx, it.attrs, it.span,
"missing documentation for a function");
}
_ => {}
}
}
}
impl Visitor<@mut Context> for MissingDocLintVisitor {
fn visit_item(&mut self, i:@item, e:@mut Context) {
self.OVERRIDE_visit_item(i, e);
}
fn visit_fn(&mut self, fk:&fn_kind, fd:&fn_decl,
b:&Block, s:span, n:NodeId, e:@mut Context) {
self.OVERRIDE_visit_fn(fk, fd, b, s, n, e);
}
fn visit_ty_method(&mut self, m:&TypeMethod, cx:@mut Context) {
// All ty_method objects are linted about because they're part of a
// trait (no visibility)
self.check_attrs(cx, m.attrs, m.span,
"missing documentation for a method");
visit::walk_ty_method(self, m, cx);
}
}
impl MissingDocLintVisitor {
fn check_attrs(&mut self,
cx: @mut Context,
attrs: &[ast::Attribute],
sp: span,
msg: &str) {
// If we're building a test harness, then warning about documentation is
// probably not really relevant right now
if cx.tcx.sess.opts.test { return }
// If we have doc(hidden), nothing to do
if cx.doc_hidden { return }
// If we're documented, nothing to do
if attrs.iter().any(|a| a.node.is_sugared_doc) { return }
// otherwise, warn!
cx.span_lint(missing_doc, sp, msg);
}
}
fn lint_missing_doc() -> MissingDocLintVisitor {
MissingDocLintVisitor { stopping_on_items: false }
}
struct LintCheckVisitor;
impl Visitor<@mut Context> for LintCheckVisitor {
fn visit_item(&mut self, it:@item, cx: @mut Context) {
do cx.with_lint_attrs(it.attrs) {
match it.node {
ast::item_impl(_, Some(*), _, _) => {
cx.in_trait_impl = true;
}
_ => {}
}
check_item_ctypes(cx, it);
check_item_non_camel_case_types(cx, it);
check_item_non_uppercase_statics(cx, it);
check_item_heap(cx, it);
cx.process(Item(it));
visit::walk_item(self, it, cx);
cx.in_trait_impl = false;
}
}
fn visit_fn(&mut self, fk:&fn_kind, decl:&fn_decl,
body:&Block, span:span, id:NodeId, cx:@mut Context) {
match *fk {
ast::fk_method(_, _, m) => {
do cx.with_lint_attrs(m.attrs) {
cx.process(Method(m));
visit::walk_fn(self,
fk,
decl,
body,
span,
id,
cx);
}
}
_ => {
visit::walk_fn(self,
fk,
decl,
body,
span,
id,
cx);
}
}
}
}
pub fn check_crate(tcx: ty::ctxt, crate: @ast::Crate) {
let cx = @mut Context {
dict: @get_lint_dict(),
curr: SmallIntMap::new(),
tcx: tcx,
lint_stack: ~[],
visitors: ~[],
in_trait_impl: false,
doc_hidden: false,
};
// Install defaults.
for (_, spec) in cx.dict.iter() {
cx.set_level(spec.lint, spec.default, Default);
}
// Install command-line options, overriding defaults.
for &(lint, level) in tcx.sess.opts.lint_opts.iter() {
cx.set_level(lint, level, CommandLine);
}
// Register each of the lint passes with the context
cx.add_oldvisit_lint(lint_while_true());
cx.add_oldvisit_lint(lint_path_statement());
cx.add_oldvisit_lint(lint_heap());
cx.add_oldvisit_lint(lint_type_limits());
cx.add_oldvisit_lint(lint_unused_unsafe());
cx.add_oldvisit_lint(lint_unused_mut());
cx.add_oldvisit_lint(lint_unnecessary_allocations());
cx.add_oldvisit_lint(lint_missing_doc());
cx.add_lint(lint_session(cx));
// Actually perform the lint checks (iterating the ast)
do cx.with_lint_attrs(crate.attrs) {
cx.process(Crate(crate));
let visitor = LintCheckVisitor;
visit::walk_crate(&mut visitor, crate, cx);
}
// If we missed any lints added to the session, then there's a bug somewhere
// in the iteration code.
for (id, v) in tcx.sess.lints.iter() {
for t in v.iter() {
match *t {
(lint, span, ref msg) =>
tcx.sess.span_bug(span, fmt!("unprocessed lint %? at %s: \
%s",
lint,
ast_map::node_id_to_str(
tcx.items,
*id,
token::get_ident_interner()),
*msg))
}
}
}
tcx.sess.abort_if_errors();
}
Raw
vist.rs
// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use ast::*;
use ast;
use codemap::span;
use parse;
use opt_vec;
use opt_vec::OptVec;
pub use ast::fn_kind;
// Context-passing AST walker. Each overridden visit method has full control
// over what happens with its node, it can do its own traversal of the node's
// children (potentially passing in different contexts to each), call
// visit::visit_* to apply the default traversal algorithm (again, it can
// override the context), or prevent deeper traversal by doing nothing.
//
// Note: it is an important invariant that the default visitor walks the body
// of a function in "execution order" (more concretely, reverse post-order
// with respect to the CFG implied by the AST), meaning that if AST node A may
// execute before AST node B, then A is visited first. The borrow checker in
// particular relies on this property.
pub fn name_of_fn(fk: &fn_kind) -> ident {
match *fk {
fk_item_fn(name, _, _, _) | fk_method(name, _, _) => {
name
}
fk_anon(*) | fk_fn_block(*) => parse::token::special_idents::anon,
}
}
pub fn generics_of_fn(fk: &fn_kind) -> Generics {
match *fk {
fk_item_fn(_, generics, _, _) |
fk_method(_, generics, _) => {
(*generics).clone()
}
fk_anon(*) | fk_fn_block(*) => {
Generics {
lifetimes: opt_vec::Empty,
ty_params: opt_vec::Empty,
}
}
}
}
pub trait Visitor<E:Clone> {
fn visit_mod(&mut self, m:&_mod, _s:span, _n:NodeId, e:E) { walk_mod(self, m, e) }
fn visit_view_item(&mut self, i:&view_item, e:E) { walk_view_item(self, i, e) }
fn visit_foreign_item(&mut self, i:@foreign_item, e:E) { walk_foreign_item(self, i, e) }
fn visit_item(&mut self, i:@item, e:E) { walk_item(self, i, e) }
fn visit_local(&mut self, l:@Local, e:E) { walk_local(self, l, e) }
fn visit_block(&mut self, b:&Block, e:E) { walk_block(self, b, e) }
fn visit_stmt(&mut self, s:@stmt, e:E) { walk_stmt(self, s, e) }
fn visit_arm(&mut self, a:&arm, e:E) { walk_arm(self, a, e) }
fn visit_pat(&mut self, p:@pat, e:E) { walk_pat(self, p, e) }
fn visit_decl(&mut self, d:@decl, e:E) { walk_decl(self, d, e) }
fn visit_expr(&mut self, ex:@expr, e:E) { walk_expr(self, ex, e) }
fn visit_expr_post(&mut self, _ex:@expr, _e:E) { }
fn visit_ty(&mut self, _t:&Ty, _e:E) { }
fn visit_generics(&mut self, g:&Generics, e:E) { walk_generics(self, g, e) }
fn visit_fn(&mut self, fk:&fn_kind, fd:&fn_decl, b:&Block, s:span, n:NodeId, e:E) {
walk_fn(self, fk, fd, b, s, n , e)
}
fn visit_ty_method(&mut self, t:&TypeMethod, e:E) { walk_ty_method(self, t, e) }
fn visit_trait_method(&mut self, t:&trait_method, e:E) { walk_trait_method(self, t, e) }
fn visit_struct_def(&mut self, s:@struct_def, i:ident, g:&Generics, n:NodeId, e:E) {
walk_struct_def(self, s, i, g, n, e)
}
fn visit_struct_field(&mut self, s:@struct_field, e:E) { walk_struct_field(self, s, e) }
}
impl<E:Clone> Visitor<E> for @mut Visitor<E> {
fn visit_mod(&mut self, a:&_mod, b:span, c:NodeId, e:E) {
(*self).visit_mod(a, b, c, e)
}
fn visit_view_item(&mut self, a:&view_item, e:E) {
(*self).visit_view_item(a, e)
}
fn visit_foreign_item(&mut self, a:@foreign_item, e:E) {
(*self).visit_foreign_item(a, e)
}
fn visit_item(&mut self, a:@item, e:E) {
(*self).visit_item(a, e)
}
fn visit_local(&mut self, a:@Local, e:E) {
(*self).visit_local(a, e)
}
fn visit_block(&mut self, a:&Block, e:E) {
(*self).visit_block(a, e)
}
fn visit_stmt(&mut self, a:@stmt, e:E) {
(*self).visit_stmt(a, e)
}
fn visit_arm(&mut self, a:&arm, e:E) {
(*self).visit_arm(a, e)
}
fn visit_pat(&mut self, a:@pat, e:E) {
(*self).visit_pat(a, e)
}
fn visit_decl(&mut self, a:@decl, e:E) {
(*self).visit_decl(a, e)
}
fn visit_expr(&mut self, a:@expr, e:E) {
(*self).visit_expr(a, e)
}
fn visit_expr_post(&mut self, a:@expr, e:E) {
(*self).visit_expr_post(a, e)
}
fn visit_ty(&mut self, a:&Ty, e:E) {
(*self).visit_ty(a, e)
}
fn visit_generics(&mut self, a:&Generics, e:E) {
(*self).visit_generics(a, e)
}
fn visit_fn(&mut self, a:&fn_kind, b:&fn_decl, c:&Block, d:span, f:NodeId, e:E) {
(*self).visit_fn(a, b, c, d, f, e)
}
fn visit_ty_method(&mut self, a:&TypeMethod, e:E) {
(*self).visit_ty_method(a, e)
}
fn visit_trait_method(&mut self, a:&trait_method, e:E) {
(*self).visit_trait_method(a, e)
}
fn visit_struct_def(&mut self, a:@struct_def, b:ident, c:&Generics, d:NodeId, e:E) {
(*self).visit_struct_def(a, b, c, d, e)
}
fn visit_struct_field(&mut self, a:@struct_field, e:E) {
(*self).visit_struct_field(a, e)
}
}
pub fn walk_crate<E:Clone, V:Visitor<E>>(visitor: &mut V, crate: &Crate, env: E) {
visitor.visit_mod(&crate.module, crate.span, CRATE_NODE_ID, env)
}
pub fn walk_mod<E:Clone, V:Visitor<E>>(visitor: &mut V, module: &_mod, env: E) {
for view_item in module.view_items.iter() {
visitor.visit_view_item(view_item, env.clone())
}
for item in module.items.iter() {
visitor.visit_item(*item, env.clone())
}
}
pub fn walk_view_item<E:Clone, V:Visitor<E>>(_: &mut V, _: &view_item, _: E) {
// Empty!
}
pub fn walk_local<E:Clone, V:Visitor<E>>(visitor: &mut V, local: &Local, env: E) {
visitor.visit_pat(local.pat, env.clone());
visitor.visit_ty(&local.ty, env.clone());
match local.init {
None => {}
Some(initializer) => visitor.visit_expr(initializer, env),
}
}
fn walk_trait_ref<E:Clone, V:Visitor<E>>(visitor: &mut V,
trait_ref: &ast::trait_ref,
env: E) {
walk_path(visitor, &trait_ref.path, env)
}
pub fn walk_item<E:Clone, V:Visitor<E>>(visitor: &mut V, item: &item, env: E) {
match item.node {
item_static(ref typ, _, expr) => {
visitor.visit_ty(typ, env.clone());
visitor.visit_expr(expr, env);
}
item_fn(ref declaration, purity, abi, ref generics, ref body) => {
visitor.visit_fn(&fk_item_fn(item.ident, generics, purity, abi),
declaration,
body,
item.span,
item.id,
env)
}
item_mod(ref module) => {
visitor.visit_mod(module, item.span, item.id, env)
}
item_foreign_mod(ref foreign_module) => {
for view_item in foreign_module.view_items.iter() {
visitor.visit_view_item(view_item, env.clone())
}
for foreign_item in foreign_module.items.iter() {
visitor.visit_foreign_item(*foreign_item, env.clone())
}
}
item_ty(ref typ, ref type_parameters) => {
visitor.visit_ty(typ, env.clone());
visitor.visit_generics(type_parameters, env)
}
item_enum(ref enum_definition, ref type_parameters) => {
visitor.visit_generics(type_parameters, env.clone());
walk_enum_def(visitor, enum_definition, type_parameters, env)
}
item_impl(ref type_parameters,
ref trait_references,
ref typ,
ref methods) => {
visitor.visit_generics(type_parameters, env.clone());
for trait_reference in trait_references.iter() {
walk_trait_ref(visitor, trait_reference, env.clone())
}
visitor.visit_ty(typ, env.clone());
for method in methods.iter() {
walk_method_helper(visitor, *method, env.clone())
}
}
item_struct(struct_definition, ref generics) => {
visitor.visit_generics(generics, env.clone());
visitor.visit_struct_def(struct_definition,
item.ident,
generics,
item.id,
env)
}
item_trait(ref generics, ref trait_paths, ref methods) => {
visitor.visit_generics(generics, env.clone());
for trait_path in trait_paths.iter() {
walk_path(visitor, &trait_path.path, env.clone())
}
for method in methods.iter() {
visitor.visit_trait_method(method, env.clone())
}
}
item_mac(ref macro) => walk_mac(visitor, macro, env),
}
}
pub fn walk_enum_def<E:Clone, V:Visitor<E>>(visitor: &mut V,
enum_definition: &ast::enum_def,
generics: &Generics,
env: E) {
for variant in enum_definition.variants.iter() {
match variant.node.kind {
tuple_variant_kind(ref variant_arguments) => {
for variant_argument in variant_arguments.iter() {
visitor.visit_ty(&variant_argument.ty, env.clone())
}
}
struct_variant_kind(struct_definition) => {
visitor.visit_struct_def(struct_definition,
variant.node.name,
generics,
variant.node.id,
env.clone())
}
}
}
}
pub fn skip_ty<E, V:Visitor<E>>(_: &mut V, _: &Ty, _: E) {
// Empty!
}
pub fn walk_ty<E:Clone, V:Visitor<E>>(visitor: &mut V, typ: &Ty, env: E) {
match typ.node {
ty_box(ref mutable_type) | ty_uniq(ref mutable_type) |
ty_vec(ref mutable_type) | ty_ptr(ref mutable_type) |
ty_rptr(_, ref mutable_type) => {
visitor.visit_ty(mutable_type.ty, env)
}
ty_tup(ref tuple_element_types) => {
for tuple_element_type in tuple_element_types.iter() {
visitor.visit_ty(tuple_element_type, env.clone())
}
}
ty_closure(ref function_declaration) => {
for argument in function_declaration.decl.inputs.iter() {
visitor.visit_ty(&argument.ty, env.clone())
}
visitor.visit_ty(&function_declaration.decl.output, env.clone());
for bounds in function_declaration.bounds.iter() {
walk_ty_param_bounds(visitor, bounds, env.clone())
}
}
ty_bare_fn(ref function_declaration) => {
for argument in function_declaration.decl.inputs.iter() {
visitor.visit_ty(&argument.ty, env.clone())
}
visitor.visit_ty(&function_declaration.decl.output, env.clone())
}
ty_path(ref path, ref bounds, _) => {
walk_path(visitor, path, env.clone());
for bounds in bounds.iter() {
walk_ty_param_bounds(visitor, bounds, env.clone())
}
}
ty_fixed_length_vec(ref mutable_type, expression) => {
visitor.visit_ty(mutable_type.ty, env.clone());
visitor.visit_expr(expression, env)
}
ty_nil | ty_bot | ty_mac(_) | ty_infer => ()
}
}
pub fn walk_path<E:Clone, V:Visitor<E>>(visitor: &mut V, path: &Path, env: E) {
for typ in path.types.iter() {
visitor.visit_ty(typ, env.clone())
}
}
pub fn walk_pat<E:Clone, V:Visitor<E>>(visitor: &mut V, pattern: &pat, env: E) {
match pattern.node {
pat_enum(ref path, ref children) => {
walk_path(visitor, path, env.clone());
for children in children.iter() {
for child in children.iter() {
visitor.visit_pat(*child, env.clone())
}
}
}
pat_struct(ref path, ref fields, _) => {
walk_path(visitor, path, env.clone());
for field in fields.iter() {
visitor.visit_pat(field.pat, env.clone())
}
}
pat_tup(ref tuple_elements) => {
for tuple_element in tuple_elements.iter() {
visitor.visit_pat(*tuple_element, env.clone())
}
}
pat_box(subpattern) |
pat_uniq(subpattern) |
pat_region(subpattern) => {
visitor.visit_pat(subpattern, env)
}
pat_ident(_, ref path, ref optional_subpattern) => {
walk_path(visitor, path, env.clone());
match *optional_subpattern {
None => {}
Some(subpattern) => visitor.visit_pat(subpattern, env),
}
}
pat_lit(expression) => visitor.visit_expr(expression, env),
pat_range(lower_bound, upper_bound) => {
visitor.visit_expr(lower_bound, env.clone());
visitor.visit_expr(upper_bound, env)
}
pat_wild => (),
pat_vec(ref prepattern, ref slice_pattern, ref postpatterns) => {
for prepattern in prepattern.iter() {
visitor.visit_pat(*prepattern, env.clone())
}
for slice_pattern in slice_pattern.iter() {
visitor.visit_pat(*slice_pattern, env.clone())
}
for postpattern in postpatterns.iter() {
visitor.visit_pat(*postpattern, env.clone())
}
}
}
}
pub fn walk_foreign_item<E:Clone, V:Visitor<E>>(visitor: &mut V,
foreign_item: &foreign_item,
env: E) {
match foreign_item.node {
foreign_item_fn(ref function_declaration, ref generics) => {
walk_fn_decl(visitor, function_declaration, env.clone());
visitor.visit_generics(generics, env)
}
foreign_item_static(ref typ, _) => visitor.visit_ty(typ, env),
}
}
pub fn walk_ty_param_bounds<E:Clone, V:Visitor<E>>(visitor: &mut V,
bounds: &OptVec<TyParamBound>,
env: E) {
for bound in bounds.iter() {
match *bound {
TraitTyParamBound(ref typ) => {
walk_trait_ref(visitor, typ, env.clone())
}
RegionTyParamBound => {}
}
}
}
pub fn walk_generics<E:Clone, V:Visitor<E>>(visitor: &mut V,
generics: &Generics,
env: E) {
for type_parameter in generics.ty_params.iter() {
walk_ty_param_bounds(visitor, &type_parameter.bounds, env.clone())
}
}
pub fn walk_fn_decl<E:Clone, V:Visitor<E>>(visitor: &mut V,
function_declaration: &fn_decl,
env: E) {
for argument in function_declaration.inputs.iter() {
visitor.visit_pat(argument.pat, env.clone());
visitor.visit_ty(&argument.ty, env.clone())
}
visitor.visit_ty(&function_declaration.output, env)
}
// Note: there is no visit_method() method in the visitor, instead override
// visit_fn() and check for fk_method(). I named this visit_method_helper()
// because it is not a default impl of any method, though I doubt that really
// clarifies anything. - Niko
pub fn walk_method_helper<E:Clone, V:Visitor<E>>(visitor: &mut V,
method: &method,
env: E) {
visitor.visit_fn(&fk_method(method.ident, &method.generics, method),
&method.decl,
&method.body,
method.span,
method.id,
env)
}
pub fn walk_fn<E:Clone, V:Visitor<E>>(visitor: &mut V,
function_kind: &fn_kind,
function_declaration: &fn_decl,
function_body: &Block,
_: span,
_: NodeId,
env: E) {
walk_fn_decl(visitor, function_declaration, env.clone());
let generics = generics_of_fn(function_kind);
visitor.visit_generics(&generics, env.clone());
visitor.visit_block(function_body, env)
}
pub fn walk_ty_method<E:Clone, V:Visitor<E>>(visitor: &mut V,
method_type: &TypeMethod,
env: E) {
for argument_type in method_type.decl.inputs.iter() {
visitor.visit_ty(&argument_type.ty, env.clone())
}
visitor.visit_generics(&method_type.generics, env.clone());
visitor.visit_ty(&method_type.decl.output, env.clone())
}
pub fn walk_trait_method<E:Clone, V:Visitor<E>>(visitor: &mut V,
trait_method: &trait_method,
env: E) {
match *trait_method {
required(ref method_type) => {
visitor.visit_ty_method(method_type, env)
}
provided(method) => walk_method_helper(visitor, method, env),
}
}
pub fn walk_struct_def<E:Clone, V:Visitor<E>>(visitor: &mut V,
struct_definition: @struct_def,
_: ast::ident,
_: &Generics,
_: NodeId,
env: E) {
for field in struct_definition.fields.iter() {
visitor.visit_struct_field(*field, env.clone())
}
}
pub fn walk_struct_field<E:Clone, V:Visitor<E>>(visitor: &mut V,
struct_field: &struct_field,
env: E) {
visitor.visit_ty(&struct_field.node.ty, env)
}
pub fn walk_block<E:Clone, V:Visitor<E>>(visitor: &mut V, block: &Block, env: E) {
for view_item in block.view_items.iter() {
visitor.visit_view_item(view_item, env.clone())
}
for statement in block.stmts.iter() {
visitor.visit_stmt(*statement, env.clone())
}
walk_expr_opt(visitor, block.expr, env)
}
pub fn walk_stmt<E:Clone, V:Visitor<E>>(visitor: &mut V, statement: &stmt, env: E) {
match statement.node {
stmt_decl(declaration, _) => visitor.visit_decl(declaration, env),
stmt_expr(expression, _) | stmt_semi(expression, _) => {
visitor.visit_expr(expression, env)
}
stmt_mac(ref macro, _) => walk_mac(visitor, macro, env),
}
}
pub fn walk_decl<E:Clone, V:Visitor<E>>(visitor: &mut V, declaration: &decl, env: E) {
match declaration.node {
decl_local(ref local) => visitor.visit_local(*local, env),
decl_item(item) => visitor.visit_item(item, env),
}
}
pub fn walk_expr_opt<E:Clone, V:Visitor<E>>(visitor: &mut V,
optional_expression: Option<@expr>,
env: E) {
match optional_expression {
None => {}
Some(expression) => visitor.visit_expr(expression, env),
}
}
pub fn walk_exprs<E:Clone, V:Visitor<E>>(visitor: &mut V,
expressions: &[@expr],
env: E) {
for expression in expressions.iter() {
visitor.visit_expr(*expression, env.clone())
}
}
pub fn walk_mac<E, V:Visitor<E>>(_: &mut V, _: &mac, _: E) {
// Empty!
}
pub fn walk_expr<E:Clone, V:Visitor<E>>(visitor: &mut V, expression: @expr, env: E) {
match expression.node {
expr_vstore(subexpression, _) => {
visitor.visit_expr(subexpression, env.clone())
}
expr_vec(ref subexpressions, _) => {
walk_exprs(visitor, *subexpressions, env.clone())
}
expr_repeat(element, count, _) => {
visitor.visit_expr(element, env.clone());
visitor.visit_expr(count, env.clone())
}
expr_struct(ref path, ref fields, optional_base) => {
walk_path(visitor, path, env.clone());
for field in fields.iter() {
visitor.visit_expr(field.expr, env.clone())
}
walk_expr_opt(visitor, optional_base, env.clone())
}
expr_tup(ref subexpressions) => {
for subexpression in subexpressions.iter() {
visitor.visit_expr(*subexpression, env.clone())
}
}
expr_call(callee_expression, ref arguments, _) => {
for argument in arguments.iter() {
visitor.visit_expr(*argument, env.clone())
}
visitor.visit_expr(callee_expression, env.clone())
}
expr_method_call(_, callee, _, ref types, ref arguments, _) => {
walk_exprs(visitor, *arguments, env.clone());
for typ in types.iter() {
visitor.visit_ty(typ, env.clone())
}
visitor.visit_expr(callee, env.clone())
}
expr_binary(_, _, left_expression, right_expression) => {
visitor.visit_expr(left_expression, env.clone());
visitor.visit_expr(right_expression, env.clone())
}
expr_addr_of(_, subexpression) |
expr_unary(_, _, subexpression) |
expr_do_body(subexpression) => {
visitor.visit_expr(subexpression, env.clone())
}
expr_lit(_) => {}
expr_cast(subexpression, ref typ) => {
visitor.visit_expr(subexpression, env.clone());
visitor.visit_ty(typ, env.clone())
}
expr_if(head_expression, ref if_block, optional_else) => {
visitor.visit_expr(head_expression, env.clone());
visitor.visit_block(if_block, env.clone());
walk_expr_opt(visitor, optional_else, env.clone())
}
expr_while(subexpression, ref block) => {
visitor.visit_expr(subexpression, env.clone());
visitor.visit_block(block, env.clone())
}
expr_for_loop(pattern, subexpression, ref block) => {
visitor.visit_pat(pattern, env.clone());
visitor.visit_expr(subexpression, env.clone());
visitor.visit_block(block, env.clone())
}
expr_loop(ref block, _) => visitor.visit_block(block, env.clone()),
expr_match(subexpression, ref arms) => {
visitor.visit_expr(subexpression, env.clone());
for arm in arms.iter() {
visitor.visit_arm(arm, env.clone())
}
}
expr_fn_block(ref function_declaration, ref body) => {
visitor.visit_fn(&fk_fn_block,
function_declaration,
body,
expression.span,
expression.id,
env.clone())
}
expr_block(ref block) => visitor.visit_block(block, env.clone()),
expr_assign(left_hand_expression, right_hand_expression) => {
visitor.visit_expr(right_hand_expression, env.clone());
visitor.visit_expr(left_hand_expression, env.clone())
}
expr_assign_op(_, _, left_expression, right_expression) => {
visitor.visit_expr(right_expression, env.clone());
visitor.visit_expr(left_expression, env.clone())
}
expr_field(subexpression, _, ref types) => {
visitor.visit_expr(subexpression, env.clone());
for typ in types.iter() {
visitor.visit_ty(typ, env.clone())
}
}
expr_index(_, main_expression, index_expression) => {
visitor.visit_expr(main_expression, env.clone());
visitor.visit_expr(index_expression, env.clone())
}
expr_path(ref path) => walk_path(visitor, path, env.clone()),
expr_self | expr_break(_) | expr_again(_) => {}
expr_ret(optional_expression) => {
walk_expr_opt(visitor, optional_expression, env.clone())
}
expr_log(level, subexpression) => {
visitor.visit_expr(level, env.clone());
visitor.visit_expr(subexpression, env.clone());
}
expr_mac(ref macro) => walk_mac(visitor, macro, env.clone()),
expr_paren(subexpression) => {
visitor.visit_expr(subexpression, env.clone())
}
expr_inline_asm(ref assembler) => {
for &(_, input) in assembler.inputs.iter() {
visitor.visit_expr(input, env.clone())
}
for &(_, output) in assembler.outputs.iter() {
visitor.visit_expr(output, env.clone())
}
}
}
visitor.visit_expr_post(expression, env.clone())
}
pub fn walk_arm<E:Clone, V:Visitor<E>>(visitor: &mut V, arm: &arm, env: E) {
for pattern in arm.pats.iter() {
visitor.visit_pat(*pattern, env.clone())
}
walk_expr_opt(visitor, arm.guard, env.clone());
visitor.visit_block(&arm.body, env)
}
// Simpler, non-context passing interface. Always walks the whole tree, simply
// calls the given functions on the nodes.
pub trait SimpleVisitor {
fn visit_mod(&mut self, &_mod, span, NodeId);
fn visit_view_item(&mut self, &view_item);
fn visit_foreign_item(&mut self, @foreign_item);
fn visit_item(&mut self, @item);
fn visit_local(&mut self, @Local);
fn visit_block(&mut self, &Block);
fn visit_stmt(&mut self, @stmt);
fn visit_arm(&mut self, &arm);
fn visit_pat(&mut self, @pat);
fn visit_decl(&mut self, @decl);
fn visit_expr(&mut self, @expr);
fn visit_expr_post(&mut self, @expr);
fn visit_ty(&mut self, &Ty);
fn visit_generics(&mut self, &Generics);
fn visit_fn(&mut self, &fn_kind, &fn_decl, &Block, span, NodeId);
fn visit_ty_method(&mut self, &TypeMethod);
fn visit_trait_method(&mut self, &trait_method);
fn visit_struct_def(&mut self, @struct_def, ident, &Generics, NodeId);
fn visit_struct_field(&mut self, @struct_field);
fn visit_struct_method(&mut self, @method);
}
pub struct SimpleVisitorVisitor {
simple_visitor: @mut SimpleVisitor,
}
impl Visitor<()> for SimpleVisitorVisitor {
fn visit_mod(&mut self,
module: &_mod,
span: span,
node_id: NodeId,
env: ()) {
self.simple_visitor.visit_mod(module, span, node_id);
walk_mod(self, module, env)
}
fn visit_view_item(&mut self, view_item: &view_item, env: ()) {
self.simple_visitor.visit_view_item(view_item);
walk_view_item(self, view_item, env)
}
fn visit_foreign_item(&mut self, foreign_item: @foreign_item, env: ()) {
self.simple_visitor.visit_foreign_item(foreign_item);
walk_foreign_item(self, foreign_item, env)
}
fn visit_item(&mut self, item: @item, env: ()) {
self.simple_visitor.visit_item(item);
walk_item(self, item, env)
}
fn visit_local(&mut self, local: @Local, env: ()) {
self.simple_visitor.visit_local(local);
walk_local(self, local, env)
}
fn visit_block(&mut self, block: &Block, env: ()) {
self.simple_visitor.visit_block(block);
walk_block(self, block, env)
}
fn visit_stmt(&mut self, statement: @stmt, env: ()) {
self.simple_visitor.visit_stmt(statement);
walk_stmt(self, statement, env)
}
fn visit_arm(&mut self, arm: &arm, env: ()) {
self.simple_visitor.visit_arm(arm);
walk_arm(self, arm, env)
}
fn visit_pat(&mut self, pattern: @pat, env: ()) {
self.simple_visitor.visit_pat(pattern);
walk_pat(self, pattern, env)
}
fn visit_decl(&mut self, declaration: @decl, env: ()) {
self.simple_visitor.visit_decl(declaration);
walk_decl(self, declaration, env)
}
fn visit_expr(&mut self, expression: @expr, env: ()) {
self.simple_visitor.visit_expr(expression);
walk_expr(self, expression, env)
}
fn visit_expr_post(&mut self, expression: @expr, _: ()) {
self.simple_visitor.visit_expr_post(expression)
}
fn visit_ty(&mut self, typ: &Ty, env: ()) {
self.simple_visitor.visit_ty(typ);
walk_ty(self, typ, env)
}
fn visit_generics(&mut self, generics: &Generics, env: ()) {
self.simple_visitor.visit_generics(generics);
walk_generics(self, generics, env)
}
fn visit_fn(&mut self,
function_kind: &fn_kind,
function_declaration: &fn_decl,
block: &Block,
span: span,
node_id: NodeId,
env: ()) {
self.simple_visitor.visit_fn(function_kind,
function_declaration,
block,
span,
node_id);
walk_fn(self,
function_kind,
function_declaration,
block,
span,
node_id,
env)
}
fn visit_ty_method(&mut self, method_type: &TypeMethod, env: ()) {
self.simple_visitor.visit_ty_method(method_type);
walk_ty_method(self, method_type, env)
}
fn visit_trait_method(&mut self, trait_method: &trait_method, env: ()) {
self.simple_visitor.visit_trait_method(trait_method);
walk_trait_method(self, trait_method, env)
}
fn visit_struct_def(&mut self,
struct_definition: @struct_def,
identifier: ident,
generics: &Generics,
node_id: NodeId,
env: ()) {
self.simple_visitor.visit_struct_def(struct_definition,
identifier,
generics,
node_id);
walk_struct_def(self,
struct_definition,
identifier,
generics,
node_id,
env)
}
fn visit_struct_field(&mut self, struct_field: @struct_field, env: ()) {
self.simple_visitor.visit_struct_field(struct_field);
walk_struct_field(self, struct_field, env)
}
}
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