ruff/crates/ruff_python_parser/tests/snapshots/valid_syntax@expressions__attribute.py.snap
Ibraheem Ahmed c9dff5c7d5
[ty] AST garbage collection (#18482)
## Summary

Garbage collect ASTs once we are done checking a given file. Queries
with a cross-file dependency on the AST will reparse the file on demand.
This reduces ty's peak memory usage by ~20-30%.

The primary change of this PR is adding a `node_index` field to every
AST node, that is assigned by the parser. `ParsedModule` can use this to
create a flat index of AST nodes any time the file is parsed (or
reparsed). This allows `AstNodeRef` to simply index into the current
instance of the `ParsedModule`, instead of storing a pointer directly.

The indices are somewhat hackily (using an atomic integer) assigned by
the `parsed_module` query instead of by the parser directly. Assigning
the indices in source-order in the (recursive) parser turns out to be
difficult, and collecting the nodes during semantic indexing is
impossible as `SemanticIndex` does not hold onto a specific
`ParsedModuleRef`, which the pointers in the flat AST are tied to. This
means that we have to do an extra AST traversal to assign and collect
the nodes into a flat index, but the small performance impact (~3% on
cold runs) seems worth it for the memory savings.

Part of https://github.com/astral-sh/ty/issues/214.
2025-06-13 08:40:11 -04:00

268 lines
12 KiB
Text

---
source: crates/ruff_python_parser/tests/fixtures.rs
input_file: crates/ruff_python_parser/resources/valid/expressions/attribute.py
---
## AST
```
Module(
ModModule {
node_index: AtomicNodeIndex(..),
range: 0..90,
body: [
Expr(
StmtExpr {
node_index: AtomicNodeIndex(..),
range: 0..10,
value: Attribute(
ExprAttribute {
node_index: AtomicNodeIndex(..),
range: 0..10,
value: Name(
ExprName {
node_index: AtomicNodeIndex(..),
range: 0..5,
id: Name("value"),
ctx: Load,
},
),
attr: Identifier {
id: Name("attr"),
range: 6..10,
node_index: AtomicNodeIndex(..),
},
ctx: Load,
},
),
},
),
Expr(
StmtExpr {
node_index: AtomicNodeIndex(..),
range: 11..23,
value: Call(
ExprCall {
node_index: AtomicNodeIndex(..),
range: 11..23,
func: Attribute(
ExprAttribute {
node_index: AtomicNodeIndex(..),
range: 11..21,
value: Name(
ExprName {
node_index: AtomicNodeIndex(..),
range: 11..16,
id: Name("value"),
ctx: Load,
},
),
attr: Identifier {
id: Name("attr"),
range: 17..21,
node_index: AtomicNodeIndex(..),
},
ctx: Load,
},
),
arguments: Arguments {
range: 21..23,
node_index: AtomicNodeIndex(..),
args: [],
keywords: [],
},
},
),
},
),
Expr(
StmtExpr {
node_index: AtomicNodeIndex(..),
range: 24..36,
value: Attribute(
ExprAttribute {
node_index: AtomicNodeIndex(..),
range: 24..36,
value: Call(
ExprCall {
node_index: AtomicNodeIndex(..),
range: 24..31,
func: Name(
ExprName {
node_index: AtomicNodeIndex(..),
range: 24..29,
id: Name("value"),
ctx: Load,
},
),
arguments: Arguments {
range: 29..31,
node_index: AtomicNodeIndex(..),
args: [],
keywords: [],
},
},
),
attr: Identifier {
id: Name("attr"),
range: 32..36,
node_index: AtomicNodeIndex(..),
},
ctx: Load,
},
),
},
),
Expr(
StmtExpr {
node_index: AtomicNodeIndex(..),
range: 37..55,
value: Attribute(
ExprAttribute {
node_index: AtomicNodeIndex(..),
range: 37..55,
value: Call(
ExprCall {
node_index: AtomicNodeIndex(..),
range: 37..51,
func: Attribute(
ExprAttribute {
node_index: AtomicNodeIndex(..),
range: 37..49,
value: Call(
ExprCall {
node_index: AtomicNodeIndex(..),
range: 37..44,
func: Name(
ExprName {
node_index: AtomicNodeIndex(..),
range: 37..42,
id: Name("value"),
ctx: Load,
},
),
arguments: Arguments {
range: 42..44,
node_index: AtomicNodeIndex(..),
args: [],
keywords: [],
},
},
),
attr: Identifier {
id: Name("attr"),
range: 45..49,
node_index: AtomicNodeIndex(..),
},
ctx: Load,
},
),
arguments: Arguments {
range: 49..51,
node_index: AtomicNodeIndex(..),
args: [],
keywords: [],
},
},
),
attr: Identifier {
id: Name("foo"),
range: 52..55,
node_index: AtomicNodeIndex(..),
},
ctx: Load,
},
),
},
),
Expr(
StmtExpr {
node_index: AtomicNodeIndex(..),
range: 56..70,
value: Attribute(
ExprAttribute {
node_index: AtomicNodeIndex(..),
range: 56..70,
value: Attribute(
ExprAttribute {
node_index: AtomicNodeIndex(..),
range: 56..66,
value: Name(
ExprName {
node_index: AtomicNodeIndex(..),
range: 56..61,
id: Name("value"),
ctx: Load,
},
),
attr: Identifier {
id: Name("attr"),
range: 62..66,
node_index: AtomicNodeIndex(..),
},
ctx: Load,
},
),
attr: Identifier {
id: Name("foo"),
range: 67..70,
node_index: AtomicNodeIndex(..),
},
ctx: Load,
},
),
},
),
Expr(
StmtExpr {
node_index: AtomicNodeIndex(..),
range: 71..89,
value: Attribute(
ExprAttribute {
node_index: AtomicNodeIndex(..),
range: 71..89,
value: Call(
ExprCall {
node_index: AtomicNodeIndex(..),
range: 71..85,
func: Attribute(
ExprAttribute {
node_index: AtomicNodeIndex(..),
range: 71..83,
value: Name(
ExprName {
node_index: AtomicNodeIndex(..),
range: 72..77,
id: Name("value"),
ctx: Load,
},
),
attr: Identifier {
id: Name("attr"),
range: 79..83,
node_index: AtomicNodeIndex(..),
},
ctx: Load,
},
),
arguments: Arguments {
range: 83..85,
node_index: AtomicNodeIndex(..),
args: [],
keywords: [],
},
},
),
attr: Identifier {
id: Name("foo"),
range: 86..89,
node_index: AtomicNodeIndex(..),
},
ctx: Load,
},
),
},
),
],
},
)
```