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
/// Dead-code detector (M18).
///
/// After Pass 2 has recorded all method/property/function references into the
/// codebase, this analyzer walks every class and reports:
///
/// - `UnusedMethod` — private method that is never called
/// - `UnusedProperty` — private property that is never read
/// - `UnusedFunction` — non-public free function that is never called
///
/// Magic methods (`__construct`, `__destruct`, `__toString`, etc.) and
/// constructors are excluded because they are called implicitly.
use mir_codebase::storage::Visibility;
use mir_codebase::Codebase;
use mir_issues::{Issue, IssueKind, Location, Severity};
use crate::stubs::StubVfs;
// Magic PHP methods that are invoked implicitly — never flag these as unused.
const MAGIC_METHODS: &[&str] = &[
"__construct",
"__destruct",
"__call",
"__callstatic",
"__get",
"__set",
"__isset",
"__unset",
"__sleep",
"__wakeup",
"__serialize",
"__unserialize",
"__tostring",
"__invoke",
"__set_state",
"__clone",
"__debuginfo",
];
pub struct DeadCodeAnalyzer<'a> {
codebase: &'a Codebase,
}
impl<'a> DeadCodeAnalyzer<'a> {
pub fn new(codebase: &'a Codebase) -> Self {
Self { codebase }
}
pub fn analyze(&self) -> Vec<Issue> {
let mut issues = Vec::new();
// --- Private methods / properties on classes ---
for entry in self.codebase.classes.iter() {
let cls = entry.value();
let fqcn = cls.fqcn.as_ref();
for (method_name, method) in &cls.own_methods {
if method.visibility != Visibility::Private {
continue;
}
let name = method_name.as_ref();
if MAGIC_METHODS.contains(&name) {
continue;
}
if !self.codebase.is_method_referenced(fqcn, name) {
let (file, line) = location_from_storage(&method.location);
issues.push(Issue::new(
IssueKind::UnusedMethod {
class: fqcn.to_string(),
method: name.to_string(),
},
Location {
file,
line,
line_end: line,
col_start: 0,
col_end: 0,
},
));
}
}
for (prop_name, prop) in &cls.own_properties {
if prop.visibility != Visibility::Private {
continue;
}
let name = prop_name.as_ref();
if !self.codebase.is_property_referenced(fqcn, name) {
let (file, line) = location_from_storage(&prop.location);
issues.push(Issue::new(
IssueKind::UnusedProperty {
class: fqcn.to_string(),
property: name.to_string(),
},
Location {
file,
line,
line_end: line,
col_start: 0,
col_end: 0,
},
));
}
}
}
// --- Non-referenced free functions ---
let stub_vfs = StubVfs::new();
for entry in self.codebase.functions.iter() {
let func = entry.value();
let fqn = func.fqn.as_ref();
// Skip PHP built-in and extension functions loaded from stubs —
// they are not user-defined dead code.
if let Some(loc) = &func.location {
if stub_vfs.is_stub_file(loc.file.as_ref()) {
continue;
}
}
if !self.codebase.is_function_referenced(fqn) {
let (file, line) = location_from_storage(&func.location);
issues.push(Issue::new(
IssueKind::UnusedFunction {
name: func.short_name.to_string(),
},
Location {
file,
line,
line_end: line,
col_start: 0,
col_end: 0,
},
));
}
}
// Downgrade all dead-code issues to Info
for issue in &mut issues {
issue.severity = Severity::Info;
}
issues
}
}
fn location_from_storage(
loc: &Option<mir_codebase::storage::Location>,
) -> (std::sync::Arc<str>, u32) {
match loc {
Some(l) => (l.file.clone(), 1), // byte offset → line mapping not available here
None => (std::sync::Arc::from("<unknown>"), 1),
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::project::ProjectAnalyzer;
#[test]
fn builtin_functions_not_flagged_as_unused() {
// The dead-code pass must not produce UnusedFunction for PHP built-ins
// (strlen, array_map, etc.) even when they are never called in user code.
// This test bypasses the fixture runner's file-path filter to verify the
// fix directly on the DeadCodeAnalyzer output.
let analyzer = ProjectAnalyzer::new();
analyzer.load_stubs();
let issues = DeadCodeAnalyzer::new(analyzer.codebase()).analyze();
let builtin_false_positives: Vec<_> = issues
.iter()
.filter(|i| {
matches!(&i.kind, IssueKind::UnusedFunction { name } if
matches!(name.as_str(), "strlen" | "array_map" | "json_encode" | "preg_match")
)
})
.collect();
assert!(
builtin_false_positives.is_empty(),
"Expected no UnusedFunction for PHP builtins, got: {:?}",
builtin_false_positives
.iter()
.map(|i| i.kind.message())
.collect::<Vec<_>>()
);
}
}