Source code
Revision control
Copy as Markdown
Other Tools
use crate::bytecode_offset::BytecodeOffset;
use crate::gcthings::GCThingIndex;
/// Maps to js::ScopeNote in m-c/js/src/vm//JSScript.h.
#[derive(Debug)]
pub struct ScopeNote {
pub index: GCThingIndex,
pub start: BytecodeOffset,
pub end: BytecodeOffset,
pub parent: Option<ScopeNoteIndex>,
}
impl ScopeNote {
fn new(index: GCThingIndex, start: BytecodeOffset, parent: Option<ScopeNoteIndex>) -> Self {
Self {
index,
start: start.clone(),
end: start,
parent,
}
}
}
/// Index into ScopeNoteList.notes.
#[derive(Debug, Clone, Copy)]
pub struct ScopeNoteIndex {
index: usize,
}
impl ScopeNoteIndex {
fn new(index: usize) -> Self {
Self { index }
}
}
impl From<ScopeNoteIndex> for usize {
fn from(index: ScopeNoteIndex) -> usize {
index.index
}
}
/// List of scope notes.
///
/// Maps to JSScript::scopeNotes() in js/src/vm/JSScript.h.
pub struct ScopeNoteList {
notes: Vec<ScopeNote>,
}
impl ScopeNoteList {
pub fn new() -> Self {
Self { notes: Vec::new() }
}
pub fn enter_scope(
&mut self,
index: GCThingIndex,
offset: BytecodeOffset,
parent: Option<ScopeNoteIndex>,
) -> ScopeNoteIndex {
let note_index = self.notes.len();
self.notes.push(ScopeNote::new(index, offset, parent));
ScopeNoteIndex::new(note_index)
}
pub fn get_scope_hole_gcthing_index(&self, scope_note_index: &ScopeNoteIndex) -> GCThingIndex {
self.notes
.get(scope_note_index.index)
.expect("Scope note should exist")
.index
}
pub fn leave_scope(&mut self, index: ScopeNoteIndex, offset: BytecodeOffset) {
self.notes[usize::from(index)].end = offset;
}
}
impl From<ScopeNoteList> for Vec<ScopeNote> {
fn from(list: ScopeNoteList) -> Vec<ScopeNote> {
list.notes
}
}