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

//! Looks for items missing (or incorrectly having) doctests.
//!
//! This pass is overloaded and runs two different lints.
//!
//! - MISSING_DOC_CODE_EXAMPLES: this lint is **UNSTABLE** and looks for public items missing doctests.
//! - PRIVATE_DOC_TESTS: this lint is **STABLE** and looks for private items with doctests.

use super::Pass;
use crate::clean;
use crate::clean::*;
use crate::core::DocContext;
use crate::html::markdown::{find_testable_code, ErrorCodes, Ignore, LangString};
use crate::visit::DocVisitor;
use crate::visit_ast::inherits_doc_hidden;
use rustc_hir as hir;
use rustc_middle::lint::LintLevelSource;
use rustc_session::lint;
use rustc_span::symbol::sym;

pub(crate) const CHECK_DOC_TEST_VISIBILITY: Pass = Pass {
    name: "check_doc_test_visibility",
    run: check_doc_test_visibility,
    description: "run various visibility-related lints on doctests",
};

struct DocTestVisibilityLinter<'a, 'tcx> {
    cx: &'a mut DocContext<'tcx>,
}

pub(crate) fn check_doc_test_visibility(krate: Crate, cx: &mut DocContext<'_>) -> Crate {
    let mut coll = DocTestVisibilityLinter { cx };
    coll.visit_crate(&krate);
    krate
}

impl<'a, 'tcx> DocVisitor for DocTestVisibilityLinter<'a, 'tcx> {
    fn visit_item(&mut self, item: &Item) {
        let dox = item.attrs.collapsed_doc_value().unwrap_or_default();

        look_for_tests(self.cx, &dox, item);

        self.visit_item_recur(item)
    }
}

pub(crate) struct Tests {
    pub(crate) found_tests: usize,
}

impl crate::doctest::Tester for Tests {
    fn add_test(&mut self, _: String, config: LangString, _: usize) {
        if config.rust && config.ignore == Ignore::None {
            self.found_tests += 1;
        }
    }
}

pub(crate) fn should_have_doc_example(cx: &DocContext<'_>, item: &clean::Item) -> bool {
    if !cx.cache.access_levels.is_public(item.item_id.expect_def_id())
        || matches!(
            *item.kind,
            clean::StructFieldItem(_)
                | clean::VariantItem(_)
                | clean::AssocConstItem(..)
                | clean::AssocTypeItem(..)
                | clean::TypedefItem(_)
                | clean::StaticItem(_)
                | clean::ConstantItem(_)
                | clean::ExternCrateItem { .. }
                | clean::ImportItem(_)
                | clean::PrimitiveItem(_)
                | clean::KeywordItem
                // check for trait impl
                | clean::ImplItem(box clean::Impl { trait_: Some(_), .. })
        )
    {
        return false;
    }

    // The `expect_def_id()` should be okay because `local_def_id_to_hir_id`
    // would presumably panic if a fake `DefIndex` were passed.
    let hir_id = cx.tcx.hir().local_def_id_to_hir_id(item.item_id.expect_def_id().expect_local());

    // check if parent is trait impl
    if let Some(parent_hir_id) = cx.tcx.hir().find_parent_node(hir_id) {
        if let Some(parent_node) = cx.tcx.hir().find(parent_hir_id) {
            if matches!(
                parent_node,
                hir::Node::Item(hir::Item {
                    kind: hir::ItemKind::Impl(hir::Impl { of_trait: Some(_), .. }),
                    ..
                })
            ) {
                return false;
            }
        }
    }

    if cx.tcx.hir().attrs(hir_id).lists(sym::doc).has_word(sym::hidden)
        || inherits_doc_hidden(cx.tcx, hir_id)
        || cx.tcx.hir().span(hir_id).in_derive_expansion()
    {
        return false;
    }
    let (level, source) = cx.tcx.lint_level_at_node(crate::lint::MISSING_DOC_CODE_EXAMPLES, hir_id);
    level != lint::Level::Allow || matches!(source, LintLevelSource::Default)
}

pub(crate) fn look_for_tests<'tcx>(cx: &DocContext<'tcx>, dox: &str, item: &Item) {
    let Some(hir_id) = DocContext::as_local_hir_id(cx.tcx, item.item_id)
    else {
        // If non-local, no need to check anything.
        return;
    };

    let mut tests = Tests { found_tests: 0 };

    find_testable_code(dox, &mut tests, ErrorCodes::No, false, None);

    if tests.found_tests == 0 && cx.tcx.features().rustdoc_missing_doc_code_examples {
        if should_have_doc_example(cx, item) {
            debug!("reporting error for {:?} (hir_id={:?})", item, hir_id);
            let sp = item.attr_span(cx.tcx);
            cx.tcx.struct_span_lint_hir(
                crate::lint::MISSING_DOC_CODE_EXAMPLES,
                hir_id,
                sp,
                |lint| {
                    lint.build("missing code example in this documentation").emit();
                },
            );
        }
    } else if tests.found_tests > 0
        && !cx.cache.access_levels.is_exported(item.item_id.expect_def_id())
    {
        cx.tcx.struct_span_lint_hir(
            crate::lint::PRIVATE_DOC_TESTS,
            hir_id,
            item.attr_span(cx.tcx),
            |lint| {
                lint.build("documentation test in private item").emit();
            },
        );
    }
}