rust-analyzer/crates/ra_hir/src/function.rs
2019-01-06 01:13:31 +01:00

248 lines
7.6 KiB
Rust

mod scope;
use std::{
cmp::{max, min},
sync::Arc,
};
use ra_db::Cancelable;
use ra_syntax::{
TextRange, TextUnit,
ast::{self, AstNode, DocCommentsOwner, NameOwner},
};
use crate::{DefId, DefKind, HirDatabase, ty::InferenceResult, Module, Crate, impl_block::ImplBlock, expr::{Body, BodySyntaxMapping}, type_ref::{TypeRef, Mutability}, Name};
pub use self::scope::{FnScopes, ScopesWithSyntaxMapping};
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct Function {
def_id: DefId,
}
impl Function {
pub(crate) fn new(def_id: DefId) -> Function {
Function { def_id }
}
pub fn def_id(&self) -> DefId {
self.def_id
}
pub fn syntax(&self, db: &impl HirDatabase) -> ast::FnDefNode {
let def_loc = self.def_id.loc(db);
assert!(def_loc.kind == DefKind::Function);
let syntax = db.file_item(def_loc.source_item_id);
ast::FnDef::cast(syntax.borrowed()).unwrap().owned()
}
pub fn body(&self, db: &impl HirDatabase) -> Cancelable<Arc<Body>> {
db.body_hir(self.def_id)
}
pub fn body_syntax_mapping(&self, db: &impl HirDatabase) -> Cancelable<Arc<BodySyntaxMapping>> {
db.body_syntax_mapping(self.def_id)
}
pub fn scopes(&self, db: &impl HirDatabase) -> Cancelable<ScopesWithSyntaxMapping> {
let scopes = db.fn_scopes(self.def_id)?;
let syntax_mapping = db.body_syntax_mapping(self.def_id)?;
Ok(ScopesWithSyntaxMapping {
scopes,
syntax_mapping,
})
}
pub fn signature(&self, db: &impl HirDatabase) -> Arc<FnSignature> {
db.fn_signature(self.def_id)
}
pub fn signature_info(&self, db: &impl HirDatabase) -> Option<FnSignatureInfo> {
let syntax = self.syntax(db);
FnSignatureInfo::new(syntax.borrowed())
}
pub fn infer(&self, db: &impl HirDatabase) -> Cancelable<Arc<InferenceResult>> {
db.infer(self.def_id)
}
pub fn module(&self, db: &impl HirDatabase) -> Cancelable<Module> {
self.def_id.module(db)
}
pub fn krate(&self, db: &impl HirDatabase) -> Cancelable<Option<Crate>> {
self.def_id.krate(db)
}
/// The containing impl block, if this is a method.
pub fn impl_block(&self, db: &impl HirDatabase) -> Cancelable<Option<ImplBlock>> {
self.def_id.impl_block(db)
}
}
/// The declared signature of a function.
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct FnSignature {
args: Vec<TypeRef>,
ret_type: TypeRef,
}
impl FnSignature {
pub fn args(&self) -> &[TypeRef] {
&self.args
}
pub fn ret_type(&self) -> &TypeRef {
&self.ret_type
}
}
pub(crate) fn fn_signature(db: &impl HirDatabase, def_id: DefId) -> Arc<FnSignature> {
let func = Function::new(def_id);
let syntax = func.syntax(db);
let node = syntax.borrowed();
let mut args = Vec::new();
if let Some(param_list) = node.param_list() {
if let Some(self_param) = param_list.self_param() {
let self_type = if let Some(type_ref) = self_param.type_ref() {
TypeRef::from_ast(type_ref)
} else {
let self_type = TypeRef::Path(Name::self_type().into());
match self_param.flavor() {
ast::SelfParamFlavor::Owned => self_type,
ast::SelfParamFlavor::Ref => {
TypeRef::Reference(Box::new(self_type), Mutability::Shared)
}
ast::SelfParamFlavor::MutRef => {
TypeRef::Reference(Box::new(self_type), Mutability::Mut)
}
}
};
args.push(self_type);
}
for param in param_list.params() {
let type_ref = TypeRef::from_ast_opt(param.type_ref());
args.push(type_ref);
}
}
let ret_type = if let Some(type_ref) = node.ret_type().and_then(|rt| rt.type_ref()) {
TypeRef::from_ast(type_ref)
} else {
TypeRef::unit()
};
let sig = FnSignature { args, ret_type };
Arc::new(sig)
}
#[derive(Debug, Clone)]
pub struct FnSignatureInfo {
pub name: String,
pub label: String,
pub ret_type: Option<String>,
pub params: Vec<String>,
pub doc: Option<String>,
}
impl FnSignatureInfo {
fn new(node: ast::FnDef) -> Option<Self> {
let name = node.name()?.text().to_string();
let mut doc = None;
// Strip the body out for the label.
let mut label: String = if let Some(body) = node.body() {
let body_range = body.syntax().range();
let label: String = node
.syntax()
.children()
.filter(|child| !child.range().is_subrange(&body_range))
.map(|node| node.text().to_string())
.collect();
label
} else {
node.syntax().text().to_string()
};
if let Some((comment_range, docs)) = FnSignatureInfo::extract_doc_comments(node) {
let comment_range = comment_range
.checked_sub(node.syntax().range().start())
.unwrap();
let start = comment_range.start().to_usize();
let end = comment_range.end().to_usize();
// Remove the comment from the label
label.replace_range(start..end, "");
// Massage markdown
let mut processed_lines = Vec::new();
let mut in_code_block = false;
for line in docs.lines() {
if line.starts_with("```") {
in_code_block = !in_code_block;
}
let line = if in_code_block && line.starts_with("```") && !line.contains("rust") {
"```rust".into()
} else {
line.to_string()
};
processed_lines.push(line);
}
if !processed_lines.is_empty() {
doc = Some(processed_lines.join("\n"));
}
}
let params = FnSignatureInfo::param_list(node);
let ret_type = node.ret_type().map(|r| r.syntax().text().to_string());
Some(FnSignatureInfo {
name,
ret_type,
params,
label: label.trim().to_owned(),
doc,
})
}
fn extract_doc_comments(node: ast::FnDef) -> Option<(TextRange, String)> {
if node.doc_comments().count() == 0 {
return None;
}
let comment_text = node.doc_comment_text();
let (begin, end) = node
.doc_comments()
.map(|comment| comment.syntax().range())
.map(|range| (range.start().to_usize(), range.end().to_usize()))
.fold((std::usize::MAX, std::usize::MIN), |acc, range| {
(min(acc.0, range.0), max(acc.1, range.1))
});
let range = TextRange::from_to(TextUnit::from_usize(begin), TextUnit::from_usize(end));
Some((range, comment_text))
}
fn param_list(node: ast::FnDef) -> Vec<String> {
let mut res = vec![];
if let Some(param_list) = node.param_list() {
if let Some(self_param) = param_list.self_param() {
res.push(self_param.syntax().text().to_string())
}
// Maybe use param.pat here? See if we can just extract the name?
//res.extend(param_list.params().map(|p| p.syntax().text().to_string()));
res.extend(
param_list
.params()
.filter_map(|p| p.pat())
.map(|pat| pat.syntax().text().to_string()),
);
}
res
}
}