Skip to content

Expand intersection reduction division strategy down to 3-member intersections #59425

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 3 commits into from
Aug 14, 2024
Merged

Expand intersection reduction division strategy down to 3-member intersections #59425

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
60cde2d
Expand divide and conquer intersection construction heuristic
weswigham Jul 25, 2024
d9d8c77
How in the world was this avoiding reentrancy before? Chance?
weswigham Jul 25, 2024
9fdf7d5
Comment update
weswigham Aug 1, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 2 additions & 2 deletions src/compiler/checker.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -18117,8 +18117,8 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
removeFromEach(typeSet, TypeFlags.Null);
result = getUnionType([getIntersectionType(typeSet, flags), nullType], UnionReduction.Literal, aliasSymbol, aliasTypeArguments);
}
else if (typeSet.length >= 4) {
// When we have four or more constituents, some of which are unions, we employ a "divide and conquer" strategy
else if (typeSet.length >= 3 && types.length > 2) {
// When we have three or more constituents, more than two inputs (to head off infinite reexpansion), some of which are unions, we employ a "divide and conquer" strategy
// where A & B & C & D is processed as (A & B) & (C & D). Since intersections of unions often produce far smaller
// unions of intersections than the full cartesian product (due to some intersections becoming `never`), this can
// dramatically reduce the overall work.
Expand Down
85 changes: 85 additions & 0 deletions tests/baselines/reference/pickOfLargeObjectUnionWorks.js
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,85 @@
//// [tests/cases/compiler/pickOfLargeObjectUnionWorks.ts] ////

//// [pickOfLargeObjectUnionWorks.ts]
interface HTMLDataAttributes {
[data: `data-${string}`]: unknown
}

interface Base {
id: string;
prop01: string;
prop02: string;
prop03: string;
prop04: string;
prop05: string;
prop06: string;
prop07: string;
prop08: string;
prop09: string;
prop10: string;
prop11: string;
prop12: string;
prop13: string;
prop14: string;
prop15: string;
prop16: string;
prop17: string;
prop18: string;
prop19: string;
prop20: string;
prop21: string;
prop22: string;
prop23: string;
prop24: string;
prop25: string;
prop26: string;
prop27: string;
prop28: string;
prop29: string;
prop30: string;
prop31: string;
prop32: string;
prop33: string;
prop34: string;
prop35: string;
prop36: string;
prop37: string;
}

interface A extends Base, HTMLDataAttributes {
a1: string;
a2: string;
a3: string;
a4: string;
a5: string;
a6: string;
a7: string;
a8: string;
}

interface B extends Base, HTMLDataAttributes {
b1: string;
b2: string;
b3: string;
b4: string;
b5: string;
b6: string;
b7: string;
b8: string;
}

interface C extends Base, HTMLDataAttributes {
c1: string;
c2: string;
c3: string;
c4: string;
c5: string;
c6: string;
c7: string;
c8: string;
}

const xyz: Pick<A | B | C, 'id'> = {id: 'id'}
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

the heuristic doesn't apply for A | B, right?

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

So this heuristic is for intersections - the way it applies here is to the key types within the mapped type. Before normalization, we construct keyof A & keyof B & keyof C which are all unions of many things - and this lets us construct it as (keyof A & keyof B) & keyof C instead, so when we see that keyof A & keyof B just becomes keyof Base (essentially), we know we can do keyof Base & keyof C without exponential blowup exceeding our limits.

Definitely doesn't apply to two element intersections, though - there's no set of comparisons to divide up.

A notable thing to say is that we attempt to do literal reduction of the intersection before the pairwise breakdown, since we can do literal-only intersection combinations in linear time (we just look for literals common to every intersected union, since them intersected with one another is always never), so this more complete division is only critical for keyof types that contain pattern literal index signatures, like in this test.


//// [pickOfLargeObjectUnionWorks.js]
var xyz = { id: 'id' };
226 changes: 226 additions & 0 deletions tests/baselines/reference/pickOfLargeObjectUnionWorks.symbols
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,226 @@
//// [tests/cases/compiler/pickOfLargeObjectUnionWorks.ts] ////

=== pickOfLargeObjectUnionWorks.ts ===
interface HTMLDataAttributes {
>HTMLDataAttributes : Symbol(HTMLDataAttributes, Decl(pickOfLargeObjectUnionWorks.ts, 0, 0))

[data: `data-${string}`]: unknown
>data : Symbol(data, Decl(pickOfLargeObjectUnionWorks.ts, 1, 5))
}

interface Base {
>Base : Symbol(Base, Decl(pickOfLargeObjectUnionWorks.ts, 2, 1))

id: string;
>id : Symbol(Base.id, Decl(pickOfLargeObjectUnionWorks.ts, 4, 16))

prop01: string;
>prop01 : Symbol(Base.prop01, Decl(pickOfLargeObjectUnionWorks.ts, 5, 15))

prop02: string;
>prop02 : Symbol(Base.prop02, Decl(pickOfLargeObjectUnionWorks.ts, 6, 19))

prop03: string;
>prop03 : Symbol(Base.prop03, Decl(pickOfLargeObjectUnionWorks.ts, 7, 19))

prop04: string;
>prop04 : Symbol(Base.prop04, Decl(pickOfLargeObjectUnionWorks.ts, 8, 19))

prop05: string;
>prop05 : Symbol(Base.prop05, Decl(pickOfLargeObjectUnionWorks.ts, 9, 19))

prop06: string;
>prop06 : Symbol(Base.prop06, Decl(pickOfLargeObjectUnionWorks.ts, 10, 19))

prop07: string;
>prop07 : Symbol(Base.prop07, Decl(pickOfLargeObjectUnionWorks.ts, 11, 19))

prop08: string;
>prop08 : Symbol(Base.prop08, Decl(pickOfLargeObjectUnionWorks.ts, 12, 19))

prop09: string;
>prop09 : Symbol(Base.prop09, Decl(pickOfLargeObjectUnionWorks.ts, 13, 19))

prop10: string;
>prop10 : Symbol(Base.prop10, Decl(pickOfLargeObjectUnionWorks.ts, 14, 19))

prop11: string;
>prop11 : Symbol(Base.prop11, Decl(pickOfLargeObjectUnionWorks.ts, 15, 19))

prop12: string;
>prop12 : Symbol(Base.prop12, Decl(pickOfLargeObjectUnionWorks.ts, 16, 19))

prop13: string;
>prop13 : Symbol(Base.prop13, Decl(pickOfLargeObjectUnionWorks.ts, 17, 19))

prop14: string;
>prop14 : Symbol(Base.prop14, Decl(pickOfLargeObjectUnionWorks.ts, 18, 19))

prop15: string;
>prop15 : Symbol(Base.prop15, Decl(pickOfLargeObjectUnionWorks.ts, 19, 19))

prop16: string;
>prop16 : Symbol(Base.prop16, Decl(pickOfLargeObjectUnionWorks.ts, 20, 19))

prop17: string;
>prop17 : Symbol(Base.prop17, Decl(pickOfLargeObjectUnionWorks.ts, 21, 19))

prop18: string;
>prop18 : Symbol(Base.prop18, Decl(pickOfLargeObjectUnionWorks.ts, 22, 19))

prop19: string;
>prop19 : Symbol(Base.prop19, Decl(pickOfLargeObjectUnionWorks.ts, 23, 19))

prop20: string;
>prop20 : Symbol(Base.prop20, Decl(pickOfLargeObjectUnionWorks.ts, 24, 19))

prop21: string;
>prop21 : Symbol(Base.prop21, Decl(pickOfLargeObjectUnionWorks.ts, 25, 19))

prop22: string;
>prop22 : Symbol(Base.prop22, Decl(pickOfLargeObjectUnionWorks.ts, 26, 19))

prop23: string;
>prop23 : Symbol(Base.prop23, Decl(pickOfLargeObjectUnionWorks.ts, 27, 19))

prop24: string;
>prop24 : Symbol(Base.prop24, Decl(pickOfLargeObjectUnionWorks.ts, 28, 19))

prop25: string;
>prop25 : Symbol(Base.prop25, Decl(pickOfLargeObjectUnionWorks.ts, 29, 19))

prop26: string;
>prop26 : Symbol(Base.prop26, Decl(pickOfLargeObjectUnionWorks.ts, 30, 19))

prop27: string;
>prop27 : Symbol(Base.prop27, Decl(pickOfLargeObjectUnionWorks.ts, 31, 19))

prop28: string;
>prop28 : Symbol(Base.prop28, Decl(pickOfLargeObjectUnionWorks.ts, 32, 19))

prop29: string;
>prop29 : Symbol(Base.prop29, Decl(pickOfLargeObjectUnionWorks.ts, 33, 19))

prop30: string;
>prop30 : Symbol(Base.prop30, Decl(pickOfLargeObjectUnionWorks.ts, 34, 19))

prop31: string;
>prop31 : Symbol(Base.prop31, Decl(pickOfLargeObjectUnionWorks.ts, 35, 19))

prop32: string;
>prop32 : Symbol(Base.prop32, Decl(pickOfLargeObjectUnionWorks.ts, 36, 19))

prop33: string;
>prop33 : Symbol(Base.prop33, Decl(pickOfLargeObjectUnionWorks.ts, 37, 19))

prop34: string;
>prop34 : Symbol(Base.prop34, Decl(pickOfLargeObjectUnionWorks.ts, 38, 19))

prop35: string;
>prop35 : Symbol(Base.prop35, Decl(pickOfLargeObjectUnionWorks.ts, 39, 19))

prop36: string;
>prop36 : Symbol(Base.prop36, Decl(pickOfLargeObjectUnionWorks.ts, 40, 19))

prop37: string;
>prop37 : Symbol(Base.prop37, Decl(pickOfLargeObjectUnionWorks.ts, 41, 19))
}

interface A extends Base, HTMLDataAttributes {
>A : Symbol(A, Decl(pickOfLargeObjectUnionWorks.ts, 43, 3))
>Base : Symbol(Base, Decl(pickOfLargeObjectUnionWorks.ts, 2, 1))
>HTMLDataAttributes : Symbol(HTMLDataAttributes, Decl(pickOfLargeObjectUnionWorks.ts, 0, 0))

a1: string;
>a1 : Symbol(A.a1, Decl(pickOfLargeObjectUnionWorks.ts, 45, 48))

a2: string;
>a2 : Symbol(A.a2, Decl(pickOfLargeObjectUnionWorks.ts, 46, 15))

a3: string;
>a3 : Symbol(A.a3, Decl(pickOfLargeObjectUnionWorks.ts, 47, 15))

a4: string;
>a4 : Symbol(A.a4, Decl(pickOfLargeObjectUnionWorks.ts, 48, 15))

a5: string;
>a5 : Symbol(A.a5, Decl(pickOfLargeObjectUnionWorks.ts, 49, 15))

a6: string;
>a6 : Symbol(A.a6, Decl(pickOfLargeObjectUnionWorks.ts, 50, 15))

a7: string;
>a7 : Symbol(A.a7, Decl(pickOfLargeObjectUnionWorks.ts, 51, 15))

a8: string;
>a8 : Symbol(A.a8, Decl(pickOfLargeObjectUnionWorks.ts, 52, 15))
}

interface B extends Base, HTMLDataAttributes {
>B : Symbol(B, Decl(pickOfLargeObjectUnionWorks.ts, 54, 3))
>Base : Symbol(Base, Decl(pickOfLargeObjectUnionWorks.ts, 2, 1))
>HTMLDataAttributes : Symbol(HTMLDataAttributes, Decl(pickOfLargeObjectUnionWorks.ts, 0, 0))

b1: string;
>b1 : Symbol(B.b1, Decl(pickOfLargeObjectUnionWorks.ts, 56, 48))

b2: string;
>b2 : Symbol(B.b2, Decl(pickOfLargeObjectUnionWorks.ts, 57, 15))

b3: string;
>b3 : Symbol(B.b3, Decl(pickOfLargeObjectUnionWorks.ts, 58, 15))

b4: string;
>b4 : Symbol(B.b4, Decl(pickOfLargeObjectUnionWorks.ts, 59, 15))

b5: string;
>b5 : Symbol(B.b5, Decl(pickOfLargeObjectUnionWorks.ts, 60, 15))

b6: string;
>b6 : Symbol(B.b6, Decl(pickOfLargeObjectUnionWorks.ts, 61, 15))

b7: string;
>b7 : Symbol(B.b7, Decl(pickOfLargeObjectUnionWorks.ts, 62, 15))

b8: string;
>b8 : Symbol(B.b8, Decl(pickOfLargeObjectUnionWorks.ts, 63, 15))
}

interface C extends Base, HTMLDataAttributes {
>C : Symbol(C, Decl(pickOfLargeObjectUnionWorks.ts, 65, 3))
>Base : Symbol(Base, Decl(pickOfLargeObjectUnionWorks.ts, 2, 1))
>HTMLDataAttributes : Symbol(HTMLDataAttributes, Decl(pickOfLargeObjectUnionWorks.ts, 0, 0))

c1: string;
>c1 : Symbol(C.c1, Decl(pickOfLargeObjectUnionWorks.ts, 67, 48))

c2: string;
>c2 : Symbol(C.c2, Decl(pickOfLargeObjectUnionWorks.ts, 68, 15))

c3: string;
>c3 : Symbol(C.c3, Decl(pickOfLargeObjectUnionWorks.ts, 69, 15))

c4: string;
>c4 : Symbol(C.c4, Decl(pickOfLargeObjectUnionWorks.ts, 70, 15))

c5: string;
>c5 : Symbol(C.c5, Decl(pickOfLargeObjectUnionWorks.ts, 71, 15))

c6: string;
>c6 : Symbol(C.c6, Decl(pickOfLargeObjectUnionWorks.ts, 72, 15))

c7: string;
>c7 : Symbol(C.c7, Decl(pickOfLargeObjectUnionWorks.ts, 73, 15))

c8: string;
>c8 : Symbol(C.c8, Decl(pickOfLargeObjectUnionWorks.ts, 74, 15))
}

const xyz: Pick<A | B | C, 'id'> = {id: 'id'}
>xyz : Symbol(xyz, Decl(pickOfLargeObjectUnionWorks.ts, 78, 7))
>Pick : Symbol(Pick, Decl(lib.es5.d.ts, --, --))
>A : Symbol(A, Decl(pickOfLargeObjectUnionWorks.ts, 43, 3))
>B : Symbol(B, Decl(pickOfLargeObjectUnionWorks.ts, 54, 3))
>C : Symbol(C, Decl(pickOfLargeObjectUnionWorks.ts, 65, 3))
>id : Symbol(id, Decl(pickOfLargeObjectUnionWorks.ts, 78, 38))

Loading