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Less template literal and string literal reduction #56165

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8e76d16
naive perf change
PranavSenthilnathan Oct 17, 2023
fc09243
update tests/baselines
PranavSenthilnathan Oct 27, 2023
339d83e
Merge branch 'main' of https://github.com/microsoft/TypeScript into p…
PranavSenthilnathan Oct 27, 2023
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2 changes: 1 addition & 1 deletion src/compiler/checker.ts
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Expand Up @@ -16960,7 +16960,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
if (includes & (TypeFlags.Enum | TypeFlags.Literal | TypeFlags.UniqueESSymbol | TypeFlags.TemplateLiteral | TypeFlags.StringMapping) || includes & TypeFlags.Void && includes & TypeFlags.Undefined) {
removeRedundantLiteralTypes(typeSet, includes, !!(unionReduction & UnionReduction.Subtype));
}
if (includes & TypeFlags.StringLiteral && includes & TypeFlags.TemplateLiteral) {
if (unionReduction === UnionReduction.Subtype && (includes & TypeFlags.StringLiteral && includes & TypeFlags.TemplateLiteral)) {
removeStringLiteralsMatchedByTemplateLiterals(typeSet);
}
if (unionReduction === UnionReduction.Subtype) {
Expand Down
2 changes: 1 addition & 1 deletion tests/baselines/reference/templateLiteralTypes3.types
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Expand Up @@ -599,5 +599,5 @@ function ft1<T extends string>(t: T, u: Uppercase<T>, u1: Uppercase<`1.${T}.3`>,
// Repro from #52685

type Boom = 'abc' | 'def' | `a${string}` | Lowercase<string>;
>Boom : `a${string}` | Lowercase<string> | "def"
>Boom : "abc" | `a${string}` | Lowercase<string> | "def"

17 changes: 12 additions & 5 deletions tests/baselines/reference/templateLiteralTypesPatterns.errors.txt
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Expand Up @@ -55,10 +55,11 @@ templateLiteralTypesPatterns.ts(129,9): error TS2345: Argument of type '"1.1e-10
templateLiteralTypesPatterns.ts(140,1): error TS2322: Type '`a${string}`' is not assignable to type '`a${number}`'.
templateLiteralTypesPatterns.ts(141,1): error TS2322: Type '"bno"' is not assignable to type '`a${any}`'.
templateLiteralTypesPatterns.ts(160,7): error TS2322: Type '"anything"' is not assignable to type '`${number} ${number}`'.
templateLiteralTypesPatterns.ts(211,5): error TS2345: Argument of type '"abcTest"' is not assignable to parameter of type '`${`a${string}` & `${string}a`}Test`'.
templateLiteralTypesPatterns.ts(178,5): error TS2403: Subsequent variable declarations must have the same type. Variable 'bb' must be of type '`${number}`', but here has type '`${number}` | "0"'.
templateLiteralTypesPatterns.ts(214,5): error TS2345: Argument of type '"abcTest"' is not assignable to parameter of type '`${`a${string}` & `${string}a`}Test`'.


==== templateLiteralTypesPatterns.ts (58 errors) ====
==== templateLiteralTypesPatterns.ts (59 errors) ====
type RequiresLeadingSlash = `/${string}`;

// ok
Expand Down Expand Up @@ -342,12 +343,18 @@ templateLiteralTypesPatterns.ts(211,5): error TS2345: Argument of type '"abcTest

// Remove string literals from unions with matching template literals

let t1: `foo${string}` | 'foo1' | '1foo'; // `foo${string}` | '1foo'
let t2: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo'; // `foo${string}` | '1foo' | 'xfoo'
let t3: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo' | `${number}foo`; // `foo${string}` | xfoo' | `${number}foo`
declare let t1: `foo${string}` | 'foo1' | '1foo';
let c1 = true ? t1 : t1; // `foo${string}` | '1foo'
declare let t2: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo';
let c2 = true ? t2 : t2; // `foo${string}` | '1foo' | 'xfoo'
declare let t3: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo' | `${number}foo`;
let c3 = true ? t3 : t3; // `foo${string}` | xfoo' | `${number}foo`

var bb: `${number}`;
var bb: `${number}` | '0';
~~
!!! error TS2403: Subsequent variable declarations must have the same type. Variable 'bb' must be of type '`${number}`', but here has type '`${number}` | "0"'.
!!! related TS6203 templateLiteralTypesPatterns.ts:177:5: 'bb' was also declared here.

// Normalize `${string}` to just string

Expand Down
16 changes: 9 additions & 7 deletions tests/baselines/reference/templateLiteralTypesPatterns.js
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Expand Up @@ -170,9 +170,12 @@ var aa: '0' & `${number}`;

// Remove string literals from unions with matching template literals

let t1: `foo${string}` | 'foo1' | '1foo'; // `foo${string}` | '1foo'
let t2: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo'; // `foo${string}` | '1foo' | 'xfoo'
let t3: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo' | `${number}foo`; // `foo${string}` | xfoo' | `${number}foo`
declare let t1: `foo${string}` | 'foo1' | '1foo';
let c1 = true ? t1 : t1; // `foo${string}` | '1foo'
declare let t2: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo';
let c2 = true ? t2 : t2; // `foo${string}` | '1foo' | 'xfoo'
declare let t3: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo' | `${number}foo`;
let c3 = true ? t3 : t3; // `foo${string}` | xfoo' | `${number}foo`

var bb: `${number}`;
var bb: `${number}` | '0';
Expand Down Expand Up @@ -337,10 +340,9 @@ var exampleGood = "1 2"; // ok
// Repro from #41161
var aa;
var aa;
// Remove string literals from unions with matching template literals
var t1; // `foo${string}` | '1foo'
var t2; // `foo${string}` | '1foo' | 'xfoo'
var t3; // `foo${string}` | xfoo' | `${number}foo`
var c1 = true ? t1 : t1; // `foo${string}` | '1foo'
var c2 = true ? t2 : t2; // `foo${string}` | '1foo' | 'xfoo'
var c3 = true ? t3 : t3; // `foo${string}` | xfoo' | `${number}foo`
var bb;
var bb;
function ff1(x) {
Expand Down
119 changes: 67 additions & 52 deletions tests/baselines/reference/templateLiteralTypesPatterns.symbols
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Expand Up @@ -405,110 +405,125 @@ var aa: '0' & `${number}`;

// Remove string literals from unions with matching template literals

let t1: `foo${string}` | 'foo1' | '1foo'; // `foo${string}` | '1foo'
>t1 : Symbol(t1, Decl(templateLiteralTypesPatterns.ts, 169, 3))
declare let t1: `foo${string}` | 'foo1' | '1foo';
>t1 : Symbol(t1, Decl(templateLiteralTypesPatterns.ts, 169, 11))

let t2: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo'; // `foo${string}` | '1foo' | 'xfoo'
>t2 : Symbol(t2, Decl(templateLiteralTypesPatterns.ts, 170, 3))
let c1 = true ? t1 : t1; // `foo${string}` | '1foo'
>c1 : Symbol(c1, Decl(templateLiteralTypesPatterns.ts, 170, 3))
>t1 : Symbol(t1, Decl(templateLiteralTypesPatterns.ts, 169, 11))
>t1 : Symbol(t1, Decl(templateLiteralTypesPatterns.ts, 169, 11))

let t3: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo' | `${number}foo`; // `foo${string}` | xfoo' | `${number}foo`
>t3 : Symbol(t3, Decl(templateLiteralTypesPatterns.ts, 171, 3))
declare let t2: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo';
>t2 : Symbol(t2, Decl(templateLiteralTypesPatterns.ts, 171, 11))

let c2 = true ? t2 : t2; // `foo${string}` | '1foo' | 'xfoo'
>c2 : Symbol(c2, Decl(templateLiteralTypesPatterns.ts, 172, 3))
>t2 : Symbol(t2, Decl(templateLiteralTypesPatterns.ts, 171, 11))
>t2 : Symbol(t2, Decl(templateLiteralTypesPatterns.ts, 171, 11))

declare let t3: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo' | `${number}foo`;
>t3 : Symbol(t3, Decl(templateLiteralTypesPatterns.ts, 173, 11))

let c3 = true ? t3 : t3; // `foo${string}` | xfoo' | `${number}foo`
>c3 : Symbol(c3, Decl(templateLiteralTypesPatterns.ts, 174, 3))
>t3 : Symbol(t3, Decl(templateLiteralTypesPatterns.ts, 173, 11))
>t3 : Symbol(t3, Decl(templateLiteralTypesPatterns.ts, 173, 11))

var bb: `${number}`;
>bb : Symbol(bb, Decl(templateLiteralTypesPatterns.ts, 173, 3), Decl(templateLiteralTypesPatterns.ts, 174, 3))
>bb : Symbol(bb, Decl(templateLiteralTypesPatterns.ts, 176, 3), Decl(templateLiteralTypesPatterns.ts, 177, 3))

var bb: `${number}` | '0';
>bb : Symbol(bb, Decl(templateLiteralTypesPatterns.ts, 173, 3), Decl(templateLiteralTypesPatterns.ts, 174, 3))
>bb : Symbol(bb, Decl(templateLiteralTypesPatterns.ts, 176, 3), Decl(templateLiteralTypesPatterns.ts, 177, 3))

// Normalize `${string}` to just string

type T2S<A extends string, B extends string> = `${A}${B}`;
>T2S : Symbol(T2S, Decl(templateLiteralTypesPatterns.ts, 174, 26))
>A : Symbol(A, Decl(templateLiteralTypesPatterns.ts, 178, 9))
>B : Symbol(B, Decl(templateLiteralTypesPatterns.ts, 178, 26))
>A : Symbol(A, Decl(templateLiteralTypesPatterns.ts, 178, 9))
>B : Symbol(B, Decl(templateLiteralTypesPatterns.ts, 178, 26))
>T2S : Symbol(T2S, Decl(templateLiteralTypesPatterns.ts, 177, 26))
>A : Symbol(A, Decl(templateLiteralTypesPatterns.ts, 181, 9))
>B : Symbol(B, Decl(templateLiteralTypesPatterns.ts, 181, 26))
>A : Symbol(A, Decl(templateLiteralTypesPatterns.ts, 181, 9))
>B : Symbol(B, Decl(templateLiteralTypesPatterns.ts, 181, 26))

type S10 = `${string}`; // string
>S10 : Symbol(S10, Decl(templateLiteralTypesPatterns.ts, 178, 58))
>S10 : Symbol(S10, Decl(templateLiteralTypesPatterns.ts, 181, 58))

type S11 = `${string}${string}${string}`; // string
>S11 : Symbol(S11, Decl(templateLiteralTypesPatterns.ts, 180, 23))
>S11 : Symbol(S11, Decl(templateLiteralTypesPatterns.ts, 183, 23))

type S12 = T2S<string, string>; // string
>S12 : Symbol(S12, Decl(templateLiteralTypesPatterns.ts, 181, 41))
>T2S : Symbol(T2S, Decl(templateLiteralTypesPatterns.ts, 174, 26))
>S12 : Symbol(S12, Decl(templateLiteralTypesPatterns.ts, 184, 41))
>T2S : Symbol(T2S, Decl(templateLiteralTypesPatterns.ts, 177, 26))

function ff1(x: `${string}-${string}`) {
>ff1 : Symbol(ff1, Decl(templateLiteralTypesPatterns.ts, 182, 31))
>x : Symbol(x, Decl(templateLiteralTypesPatterns.ts, 184, 13))
>ff1 : Symbol(ff1, Decl(templateLiteralTypesPatterns.ts, 185, 31))
>x : Symbol(x, Decl(templateLiteralTypesPatterns.ts, 187, 13))

let s1 = x && 42; // number
>s1 : Symbol(s1, Decl(templateLiteralTypesPatterns.ts, 185, 7))
>x : Symbol(x, Decl(templateLiteralTypesPatterns.ts, 184, 13))
>s1 : Symbol(s1, Decl(templateLiteralTypesPatterns.ts, 188, 7))
>x : Symbol(x, Decl(templateLiteralTypesPatterns.ts, 187, 13))

let s2 = x || 42; // `${string}-${string}`
>s2 : Symbol(s2, Decl(templateLiteralTypesPatterns.ts, 186, 7))
>x : Symbol(x, Decl(templateLiteralTypesPatterns.ts, 184, 13))
>s2 : Symbol(s2, Decl(templateLiteralTypesPatterns.ts, 189, 7))
>x : Symbol(x, Decl(templateLiteralTypesPatterns.ts, 187, 13))
}

// Repro from #41651

export type Id<TA, TId extends string = string> = `${TId}-${TId}`;
>Id : Symbol(Id, Decl(templateLiteralTypesPatterns.ts, 187, 1))
>TA : Symbol(TA, Decl(templateLiteralTypesPatterns.ts, 191, 15))
>TId : Symbol(TId, Decl(templateLiteralTypesPatterns.ts, 191, 18))
>TId : Symbol(TId, Decl(templateLiteralTypesPatterns.ts, 191, 18))
>TId : Symbol(TId, Decl(templateLiteralTypesPatterns.ts, 191, 18))
>Id : Symbol(Id, Decl(templateLiteralTypesPatterns.ts, 190, 1))
>TA : Symbol(TA, Decl(templateLiteralTypesPatterns.ts, 194, 15))
>TId : Symbol(TId, Decl(templateLiteralTypesPatterns.ts, 194, 18))
>TId : Symbol(TId, Decl(templateLiteralTypesPatterns.ts, 194, 18))
>TId : Symbol(TId, Decl(templateLiteralTypesPatterns.ts, 194, 18))

export class AA {}
>AA : Symbol(AA, Decl(templateLiteralTypesPatterns.ts, 191, 66))
>AA : Symbol(AA, Decl(templateLiteralTypesPatterns.ts, 194, 66))

export abstract class BB {
>BB : Symbol(BB, Decl(templateLiteralTypesPatterns.ts, 193, 18))
>BB : Symbol(BB, Decl(templateLiteralTypesPatterns.ts, 196, 18))

abstract get(id: Id<AA>): void;
>get : Symbol(BB.get, Decl(templateLiteralTypesPatterns.ts, 195, 26))
>id : Symbol(id, Decl(templateLiteralTypesPatterns.ts, 196, 17))
>Id : Symbol(Id, Decl(templateLiteralTypesPatterns.ts, 187, 1))
>AA : Symbol(AA, Decl(templateLiteralTypesPatterns.ts, 191, 66))
>get : Symbol(BB.get, Decl(templateLiteralTypesPatterns.ts, 198, 26))
>id : Symbol(id, Decl(templateLiteralTypesPatterns.ts, 199, 17))
>Id : Symbol(Id, Decl(templateLiteralTypesPatterns.ts, 190, 1))
>AA : Symbol(AA, Decl(templateLiteralTypesPatterns.ts, 194, 66))

update(id: Id<AA>): void {
>update : Symbol(BB.update, Decl(templateLiteralTypesPatterns.ts, 196, 35))
>id : Symbol(id, Decl(templateLiteralTypesPatterns.ts, 197, 11))
>Id : Symbol(Id, Decl(templateLiteralTypesPatterns.ts, 187, 1))
>AA : Symbol(AA, Decl(templateLiteralTypesPatterns.ts, 191, 66))
>update : Symbol(BB.update, Decl(templateLiteralTypesPatterns.ts, 199, 35))
>id : Symbol(id, Decl(templateLiteralTypesPatterns.ts, 200, 11))
>Id : Symbol(Id, Decl(templateLiteralTypesPatterns.ts, 190, 1))
>AA : Symbol(AA, Decl(templateLiteralTypesPatterns.ts, 194, 66))

this.get(id!);
>this.get : Symbol(BB.get, Decl(templateLiteralTypesPatterns.ts, 195, 26))
>this : Symbol(BB, Decl(templateLiteralTypesPatterns.ts, 193, 18))
>get : Symbol(BB.get, Decl(templateLiteralTypesPatterns.ts, 195, 26))
>id : Symbol(id, Decl(templateLiteralTypesPatterns.ts, 197, 11))
>this.get : Symbol(BB.get, Decl(templateLiteralTypesPatterns.ts, 198, 26))
>this : Symbol(BB, Decl(templateLiteralTypesPatterns.ts, 196, 18))
>get : Symbol(BB.get, Decl(templateLiteralTypesPatterns.ts, 198, 26))
>id : Symbol(id, Decl(templateLiteralTypesPatterns.ts, 200, 11))
}
}

// repro from https://github.com/microsoft/TypeScript/issues/54177#issuecomment-1538436654
function conversionTest(groupName: | "downcast" | "dataDowncast" | "editingDowncast" | `${string & {}}Downcast`) {}
>conversionTest : Symbol(conversionTest, Decl(templateLiteralTypesPatterns.ts, 200, 1))
>groupName : Symbol(groupName, Decl(templateLiteralTypesPatterns.ts, 203, 24))
>conversionTest : Symbol(conversionTest, Decl(templateLiteralTypesPatterns.ts, 203, 1))
>groupName : Symbol(groupName, Decl(templateLiteralTypesPatterns.ts, 206, 24))

conversionTest("testDowncast");
>conversionTest : Symbol(conversionTest, Decl(templateLiteralTypesPatterns.ts, 200, 1))
>conversionTest : Symbol(conversionTest, Decl(templateLiteralTypesPatterns.ts, 203, 1))

function conversionTest2(groupName: | "downcast" | "dataDowncast" | "editingDowncast" | `${{} & string}Downcast`) {}
>conversionTest2 : Symbol(conversionTest2, Decl(templateLiteralTypesPatterns.ts, 204, 31))
>groupName : Symbol(groupName, Decl(templateLiteralTypesPatterns.ts, 205, 25))
>conversionTest2 : Symbol(conversionTest2, Decl(templateLiteralTypesPatterns.ts, 207, 31))
>groupName : Symbol(groupName, Decl(templateLiteralTypesPatterns.ts, 208, 25))

conversionTest2("testDowncast");
>conversionTest2 : Symbol(conversionTest2, Decl(templateLiteralTypesPatterns.ts, 204, 31))
>conversionTest2 : Symbol(conversionTest2, Decl(templateLiteralTypesPatterns.ts, 207, 31))

function foo(str: `${`a${string}` & `${string}a`}Test`) {}
>foo : Symbol(foo, Decl(templateLiteralTypesPatterns.ts, 206, 32))
>str : Symbol(str, Decl(templateLiteralTypesPatterns.ts, 208, 13))
>foo : Symbol(foo, Decl(templateLiteralTypesPatterns.ts, 209, 32))
>str : Symbol(str, Decl(templateLiteralTypesPatterns.ts, 211, 13))

foo("abaTest"); // ok
>foo : Symbol(foo, Decl(templateLiteralTypesPatterns.ts, 206, 32))
>foo : Symbol(foo, Decl(templateLiteralTypesPatterns.ts, 209, 32))

foo("abcTest"); // error
>foo : Symbol(foo, Decl(templateLiteralTypesPatterns.ts, 206, 32))
>foo : Symbol(foo, Decl(templateLiteralTypesPatterns.ts, 209, 32))

33 changes: 27 additions & 6 deletions tests/baselines/reference/templateLiteralTypesPatterns.types
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Expand Up @@ -560,14 +560,35 @@ var aa: '0' & `${number}`;

// Remove string literals from unions with matching template literals

let t1: `foo${string}` | 'foo1' | '1foo'; // `foo${string}` | '1foo'
>t1 : `foo${string}` | "1foo"
declare let t1: `foo${string}` | 'foo1' | '1foo';
>t1 : `foo${string}` | "foo1" | "1foo"

let t2: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo'; // `foo${string}` | '1foo' | 'xfoo'
>t2 : `foo${string}` | "1foo" | "xfoo"
let c1 = true ? t1 : t1; // `foo${string}` | '1foo'
>c1 : `foo${string}` | "1foo"
>true ? t1 : t1 : `foo${string}` | "1foo"
>true : true
>t1 : `foo${string}` | "foo1" | "1foo"
>t1 : `foo${string}` | "foo1" | "1foo"

declare let t2: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo';
>t2 : `foo${string}` | "foo1" | "1foo" | "foofoo" | "foox" | "xfoo"

let c2 = true ? t2 : t2; // `foo${string}` | '1foo' | 'xfoo'
>c2 : `foo${string}` | "1foo" | "xfoo"
>true ? t2 : t2 : `foo${string}` | "1foo" | "xfoo"
>true : true
>t2 : `foo${string}` | "foo1" | "1foo" | "foofoo" | "foox" | "xfoo"
>t2 : `foo${string}` | "foo1" | "1foo" | "foofoo" | "foox" | "xfoo"

declare let t3: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo' | `${number}foo`;
>t3 : `foo${string}` | "foo1" | "1foo" | "foofoo" | "foox" | "xfoo" | `${number}foo`

let t3: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo' | `${number}foo`; // `foo${string}` | xfoo' | `${number}foo`
>t3 : `foo${string}` | "xfoo" | `${number}foo`
let c3 = true ? t3 : t3; // `foo${string}` | xfoo' | `${number}foo`
>c3 : `foo${string}` | "xfoo" | `${number}foo`
>true ? t3 : t3 : `foo${string}` | "xfoo" | `${number}foo`
>true : true
>t3 : `foo${string}` | "foo1" | "1foo" | "foofoo" | "foox" | "xfoo" | `${number}foo`
>t3 : `foo${string}` | "foo1" | "1foo" | "foofoo" | "foox" | "xfoo" | `${number}foo`

var bb: `${number}`;
>bb : `${number}`
Expand Down
9 changes: 6 additions & 3 deletions tests/cases/conformance/types/literal/templateLiteralTypesPatterns.ts
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Expand Up @@ -168,9 +168,12 @@ var aa: '0' & `${number}`;

// Remove string literals from unions with matching template literals

let t1: `foo${string}` | 'foo1' | '1foo'; // `foo${string}` | '1foo'
let t2: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo'; // `foo${string}` | '1foo' | 'xfoo'
let t3: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo' | `${number}foo`; // `foo${string}` | xfoo' | `${number}foo`
declare let t1: `foo${string}` | 'foo1' | '1foo';
let c1 = true ? t1 : t1; // `foo${string}` | '1foo'
declare let t2: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo';
let c2 = true ? t2 : t2; // `foo${string}` | '1foo' | 'xfoo'
declare let t3: `foo1` | '1foo' | 'foofoo' | `foo${string}` | 'foox' | 'xfoo' | `${number}foo`;
let c3 = true ? t3 : t3; // `foo${string}` | xfoo' | `${number}foo`

var bb: `${number}`;
var bb: `${number}` | '0';
Expand Down