1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189

use std::time::Instant;

use rnode::VisitWith;
use stc_ts_ast_rnode::{RBlockStmt, RBool, RDecl, RExpr, RExprStmt, RForStmt, RModuleItem, RStmt, RTsExprWithTypeArgs, RTsLit, RWithStmt};
use stc_ts_errors::{DebugExt, ErrorKind};
use stc_ts_types::{LitType, Type};
use stc_utils::{dev_span, stack};
use swc_common::{Spanned, DUMMY_SP};
use swc_ecma_utils::Value::Known;
use tracing::{trace, warn};

use self::return_type::LoopBreakerFinder;
use crate::{
    analyzer::{scope::ScopeKind, util::ResultExt, Analyzer},
    validator,
    validator::ValidateWith,
};

mod ambient_decl;
mod loops;
pub(crate) mod return_type;
mod try_catch;
mod var_decl;

#[validator]
impl Analyzer<'_, '_> {
    fn validate(&mut self, i: &RModuleItem) {
        let _stack = stack::start(100);

        i.visit_children_with(self);

        Ok(())
    }
}

#[validator]
impl Analyzer<'_, '_> {
    fn validate(&mut self, s: &RStmt) {
        let span = s.span();
        let line_col = self.line_col(span);

        let _tracing = dev_span!("Stmt", line_col = &*line_col);

        warn!("Statement start");
        let start = Instant::now();

        if self.rule().always_strict && !self.rule().allow_unreachable_code && self.ctx.in_unreachable {
            if !matches!(s, RStmt::Decl(RDecl::TsInterface(..) | RDecl::TsTypeAlias(..))) {
                self.storage.report(ErrorKind::UnreachableCode { span: s.span() }.into());
            }
        }

        let old_in_conditional = self.scope.return_values.in_conditional;
        self.scope.return_values.in_conditional |= matches!(s, RStmt::If(_) | RStmt::Switch(_));

        s.visit_children_with(self);

        self.scope.return_values.in_conditional = old_in_conditional;

        let end = Instant::now();

        warn!(
            kind = "perf",
            op = "validate (Stmt)",
            "({}): Statement validation done. (time = {:?}",
            line_col,
            end - start
        );

        Ok(())
    }
}

impl Analyzer<'_, '_> {
    fn check_for_infinite_loop(&mut self, test: &Type, body: &RStmt) {
        trace!("Checking for infinite loop");

        // Of `s` is always executed and we enter infinite loop, return type should be
        // never
        if !self.scope.return_values.in_conditional {
            let mut v = LoopBreakerFinder { found: false };
            body.visit_with(&mut v);
            let has_break = v.found;
            if !has_break {
                if let Known(v) = test.as_bool() {
                    self.ctx.in_unreachable = true;
                }
            }
        }
    }
}

#[validator]
impl Analyzer<'_, '_> {
    fn validate(&mut self, node: &RForStmt) {
        node.init.visit_with(self);

        let test = try_opt!(node.test.validate_with_default(self));
        let always_true = Type::Lit(LitType {
            span: node.span,
            lit: RTsLit::Bool(RBool {
                span: DUMMY_SP,
                value: true,
            }),
            metadata: Default::default(),
            tracker: Default::default(),
        });

        node.update.visit_with(self);
        node.body.validate_with(self)?;

        self.check_for_infinite_loop(test.as_ref().unwrap_or(&always_true), &node.body);

        Ok(())
    }
}

/// NOTE: We does **not** dig into with statements.
#[validator]
impl Analyzer<'_, '_> {
    fn validate(&mut self, s: &RWithStmt) {
        self.storage.report(ErrorKind::WithStmtNotSupported { span: s.span }.into());

        s.obj.visit_with(self);

        Ok(())
    }
}

#[validator]
impl Analyzer<'_, '_> {
    fn validate(&mut self, s: &RBlockStmt) {
        self.with_child(ScopeKind::Block, Default::default(), |analyzer| {
            s.stmts.visit_with(analyzer);
            Ok(())
        })?;

        Ok(())
    }
}

impl Analyzer<'_, '_> {
    /// Validate that parent interfaces are all resolved.
    pub(super) fn resolve_parent_interfaces(&mut self, parents: &[RTsExprWithTypeArgs], is_for_interface: bool) {
        let _tracing = dev_span!("resolve_parent_interfaces");

        if self.config.is_builtin {
            return;
        }

        for parent in parents {
            // Verify parent interface
            let res: Result<_, _> = try {
                let type_args = try_opt!(parent.type_args.validate_with(self));
                let span = parent.span;

                self.report_error_for_unresolved_type(span, &parent.expr, type_args.as_ref())
                    .convert_err(|err| match err {
                        ErrorKind::TypeNotFound {
                            name,
                            ctxt,
                            type_args,
                            span,
                        } if is_for_interface => ErrorKind::NotExtendableType { span },
                        _ => err,
                    })?;
            };

            res.report(&mut self.storage);
        }
    }
}

#[validator]
impl Analyzer<'_, '_> {
    fn validate(&mut self, node: &RExprStmt) {
        let preserve_cond_facts = !matches!(&*node.expr, RExpr::Call(..));

        let prev_cond_facts = self.cur_facts.clone();

        node.expr.visit_with(self);

        if preserve_cond_facts {
            self.cur_facts = prev_cond_facts;
        }

        Ok(())
    }
}