php_lsp/hover/
parsing.rs

1use php_ast::{NamespaceBody, Stmt, StmtKind, UseKind};
2
3use crate::util::fqn_short_name;
4
5/// Extract the receiver variable from immediately before `->word` or `?->word`
6/// at the cursor's exact column position.  Uses the column rather than
7/// `str::find()` so multiple method calls on the same line are handled
8/// correctly.
9pub fn extract_receiver_var_before_cursor(line: &str, cursor_col_utf16: usize) -> Option<String> {
10    let chars: Vec<char> = line.chars().collect();
11
12    // Convert UTF-16 cursor column to char index.
13    let mut utf16 = 0usize;
14    let mut char_idx = 0usize;
15    for ch in &chars {
16        if utf16 >= cursor_col_utf16 {
17            break;
18        }
19        utf16 += ch.len_utf16();
20        char_idx += 1;
21    }
22
23    // Find the start of the word under the cursor (expand left).
24    let is_word_char = |c: char| c.is_alphanumeric() || c == '_';
25    let mut word_start = char_idx;
26    while word_start > 0 && is_word_char(chars[word_start - 1]) {
27        word_start -= 1;
28    }
29
30    // Check for `?->` (3 chars) or `->` (2 chars) immediately before word_start.
31    let (is_arrow, arrow_end) = if word_start >= 3
32        && chars[word_start - 3] == '?'
33        && chars[word_start - 2] == '-'
34        && chars[word_start - 1] == '>'
35    {
36        (true, word_start - 3)
37    } else if word_start >= 2 && chars[word_start - 2] == '-' && chars[word_start - 1] == '>' {
38        (true, word_start - 2)
39    } else {
40        (false, 0)
41    };
42
43    if !is_arrow {
44        return None;
45    }
46
47    extract_name_from_chars_end(&chars[..arrow_end])
48}
49
50/// Extract the class name from immediately before `::` at the cursor's column.
51pub(crate) fn extract_static_class_before_cursor(
52    line: &str,
53    cursor_col_utf16: usize,
54) -> Option<String> {
55    let chars: Vec<char> = line.chars().collect();
56
57    let mut utf16 = 0usize;
58    let mut char_idx = 0usize;
59    for ch in &chars {
60        if utf16 >= cursor_col_utf16 {
61            break;
62        }
63        utf16 += ch.len_utf16();
64        char_idx += 1;
65    }
66
67    let is_word_char = |c: char| c.is_alphanumeric() || c == '_';
68    let mut word_start = char_idx;
69    while word_start > 0 && is_word_char(chars[word_start - 1]) {
70        word_start -= 1;
71    }
72
73    // For `Class::$prop`, skip the `$` before checking for `::`
74    if word_start > 0 && chars[word_start - 1] == '$' {
75        word_start -= 1;
76    }
77
78    if word_start < 2 || chars[word_start - 2] != ':' || chars[word_start - 1] != ':' {
79        return None;
80    }
81
82    let before_colons = &chars[..word_start - 2];
83    // Class name may contain `\` for FQN; extract the short name (last segment).
84    let is_name_char = |c: char| c.is_alphanumeric() || c == '_' || c == '\\';
85    let end = before_colons.len().saturating_sub(
86        before_colons
87            .iter()
88            .rev()
89            .take_while(|&&c| c == ' ' || c == '\t')
90            .count(),
91    );
92    let mut start = end;
93    while start > 0 && is_name_char(before_colons[start - 1]) {
94        start -= 1;
95    }
96    if start == end {
97        return None;
98    }
99    let full: String = before_colons[start..end].iter().collect();
100    // Return only the last segment so callers get a short name.
101    Some(fqn_short_name(&full).to_owned())
102}
103
104/// Walk backwards through `chars`, skipping whitespace, and return the
105/// identifier (with `$` prefix if present) ending at the last non-space char.
106pub(crate) fn extract_name_from_chars_end(chars: &[char]) -> Option<String> {
107    let is_var_char = |c: char| c.is_alphanumeric() || c == '_' || c == '$';
108    let end = chars.len()
109        - chars
110            .iter()
111            .rev()
112            .take_while(|&&c| c == ' ' || c == '\t')
113            .count();
114    if end == 0 {
115        return None;
116    }
117    let mut start = end;
118    while start > 0 && is_var_char(chars[start - 1]) {
119        start -= 1;
120    }
121    if start == end {
122        return None;
123    }
124    let name: String = chars[start..end].iter().collect();
125    if name.starts_with('$') && name.len() > 1 {
126        Some(name)
127    } else if !name.is_empty() && !name.starts_with('$') {
128        // Plain identifier (e.g. `$obj->getUser()->name` — the inner result):
129        // treat as a non-variable receiver; callers handle the `$` lookup.
130        Some(format!("${}", name))
131    } else {
132        None
133    }
134}
135
136/// Resolve a use-import alias to the short class name.
137///
138/// Given `use App\Foo as Bar`, hovering on `Bar` anywhere in the file should
139/// resolve to `Foo` so the declaration lookup succeeds.
140pub fn resolve_use_alias(stmts: &[Stmt<'_, '_>], word: &str) -> Option<String> {
141    for stmt in stmts {
142        match &stmt.kind {
143            StmtKind::Use(u) if u.kind == UseKind::Normal => {
144                for item in u.uses.iter() {
145                    if let Some(alias) = item.alias
146                        && alias == word
147                    {
148                        let fqn = item.name.to_string_repr();
149                        let short = fqn_short_name(&fqn).to_owned();
150                        return Some(short);
151                    }
152                }
153            }
154            StmtKind::Namespace(ns) => {
155                if let NamespaceBody::Braced(inner) = &ns.body
156                    && let Some(s) = resolve_use_alias(&inner.stmts, word)
157                {
158                    return Some(s);
159                }
160            }
161            _ => {}
162        }
163    }
164    None
165}
php_lsp/hover/parsing.rs

php_lsp/hover/
parsing.rs
