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
190
191
192
193
194
195
196
|
//! See [`complete_fn_param`].
use hir::HirDisplay;
use ide_db::FxHashMap;
use syntax::{
algo,
ast::{self, HasModuleItem},
match_ast, AstNode, Direction, SyntaxKind, TextRange, TextSize,
};
use crate::{
context::{ParamContext, ParamKind, PatternContext},
CompletionContext, CompletionItem, CompletionItemKind, Completions,
};
// FIXME: Make this a submodule of [`pattern`]
/// Complete repeated parameters, both name and type. For example, if all
/// functions in a file have a `spam: &mut Spam` parameter, a completion with
/// `spam: &mut Spam` insert text/label will be suggested.
///
/// Also complete parameters for closure or local functions from the surrounding defined locals.
pub(crate) fn complete_fn_param(
acc: &mut Completions,
ctx: &CompletionContext<'_>,
pattern_ctx: &PatternContext,
) -> Option<()> {
let (ParamContext { param_list, kind, .. }, impl_) = match pattern_ctx {
PatternContext { param_ctx: Some(kind), impl_, .. } => (kind, impl_),
_ => return None,
};
let comma_wrapper = comma_wrapper(ctx);
let mut add_new_item_to_acc = |label: &str| {
let mk_item = |label: &str, range: TextRange| {
CompletionItem::new(CompletionItemKind::Binding, range, label)
};
let item = match &comma_wrapper {
Some((fmt, range)) => mk_item(&fmt(label), *range),
None => mk_item(label, ctx.source_range()),
};
// Completion lookup is omitted intentionally here.
// See the full discussion: https://github.com/rust-lang/rust-analyzer/issues/12073
item.add_to(acc)
};
match kind {
ParamKind::Function(function) => {
fill_fn_params(ctx, function, param_list, impl_, add_new_item_to_acc);
}
ParamKind::Closure(closure) => {
let stmt_list = closure.syntax().ancestors().find_map(ast::StmtList::cast)?;
params_from_stmt_list_scope(ctx, stmt_list, |name, ty| {
add_new_item_to_acc(&format!("{name}: {ty}"));
});
}
}
Some(())
}
fn fill_fn_params(
ctx: &CompletionContext<'_>,
function: &ast::Fn,
param_list: &ast::ParamList,
impl_: &Option<ast::Impl>,
mut add_new_item_to_acc: impl FnMut(&str),
) {
let mut file_params = FxHashMap::default();
let mut extract_params = |f: ast::Fn| {
f.param_list().into_iter().flat_map(|it| it.params()).for_each(|param| {
if let Some(pat) = param.pat() {
// FIXME: We should be able to turn these into SmolStr without having to allocate a String
let whole_param = param.syntax().text().to_string();
let binding = pat.syntax().text().to_string();
file_params.entry(whole_param).or_insert(binding);
}
});
};
for node in ctx.token.parent_ancestors() {
match_ast! {
match node {
ast::SourceFile(it) => it.items().filter_map(|item| match item {
ast::Item::Fn(it) => Some(it),
_ => None,
}).for_each(&mut extract_params),
ast::ItemList(it) => it.items().filter_map(|item| match item {
ast::Item::Fn(it) => Some(it),
_ => None,
}).for_each(&mut extract_params),
ast::AssocItemList(it) => it.assoc_items().filter_map(|item| match item {
ast::AssocItem::Fn(it) => Some(it),
_ => None,
}).for_each(&mut extract_params),
_ => continue,
}
};
}
if let Some(stmt_list) = function.syntax().parent().and_then(ast::StmtList::cast) {
params_from_stmt_list_scope(ctx, stmt_list, |name, ty| {
file_params.entry(format!("{name}: {ty}")).or_insert(name.to_string());
});
}
remove_duplicated(&mut file_params, param_list.params());
let self_completion_items = ["self", "&self", "mut self", "&mut self"];
if should_add_self_completions(ctx.token.text_range().start(), param_list, impl_) {
self_completion_items.into_iter().for_each(|self_item| add_new_item_to_acc(self_item));
}
file_params.keys().for_each(|whole_param| add_new_item_to_acc(whole_param));
}
fn params_from_stmt_list_scope(
ctx: &CompletionContext<'_>,
stmt_list: ast::StmtList,
mut cb: impl FnMut(hir::Name, String),
) {
let syntax_node = match stmt_list.syntax().last_child() {
Some(it) => it,
None => return,
};
if let Some(scope) =
ctx.sema.scope_at_offset(stmt_list.syntax(), syntax_node.text_range().end())
{
let module = scope.module().into();
scope.process_all_names(&mut |name, def| {
if let hir::ScopeDef::Local(local) = def {
if let Ok(ty) = local.ty(ctx.db).display_source_code(ctx.db, module) {
cb(name, ty);
}
}
});
}
}
fn remove_duplicated(
file_params: &mut FxHashMap<String, String>,
fn_params: ast::AstChildren<ast::Param>,
) {
fn_params.for_each(|param| {
let whole_param = param.syntax().text().to_string();
file_params.remove(&whole_param);
match param.pat() {
// remove suggestions for patterns that already exist
// if the type is missing we are checking the current param to be completed
// in which case this would find itself removing the suggestions due to itself
Some(pattern) if param.ty().is_some() => {
let binding = pattern.syntax().text().to_string();
file_params.retain(|_, v| v != &binding);
}
_ => (),
}
})
}
fn should_add_self_completions(
cursor: TextSize,
param_list: &ast::ParamList,
impl_: &Option<ast::Impl>,
) -> bool {
if impl_.is_none() || param_list.self_param().is_some() {
return false;
}
match param_list.params().next() {
Some(first) => first.pat().map_or(false, |pat| pat.syntax().text_range().contains(cursor)),
None => true,
}
}
fn comma_wrapper(ctx: &CompletionContext<'_>) -> Option<(impl Fn(&str) -> String, TextRange)> {
let param = ctx.token.parent_ancestors().find(|node| node.kind() == SyntaxKind::PARAM)?;
let next_token_kind = {
let t = param.last_token()?.next_token()?;
let t = algo::skip_whitespace_token(t, Direction::Next)?;
t.kind()
};
let prev_token_kind = {
let t = param.first_token()?.prev_token()?;
let t = algo::skip_whitespace_token(t, Direction::Prev)?;
t.kind()
};
let has_trailing_comma =
matches!(next_token_kind, SyntaxKind::COMMA | SyntaxKind::R_PAREN | SyntaxKind::PIPE);
let trailing = if has_trailing_comma { "" } else { "," };
let has_leading_comma =
matches!(prev_token_kind, SyntaxKind::COMMA | SyntaxKind::L_PAREN | SyntaxKind::PIPE);
let leading = if has_leading_comma { "" } else { ", " };
Some((move |label: &_| (format!("{leading}{label}{trailing}")), param.text_range()))
}
|
