feat(compiler): support unary operators for more accurate type checking (#37918)
Prior to this change, the unary + and - operators would be parsed as `x - 0` and `0 - x` respectively. The runtime semantics of these expressions are equivalent, however they may introduce inaccurate template type checking errors as the literal type is lost, for example: ```ts @Component({ template: `<button [disabled]="isAdjacent(-1)"></button>` }) export class Example { isAdjacent(direction: -1 | 1): boolean { return false; } } ``` would incorrectly report a type-check error: > error TS2345: Argument of type 'number' is not assignable to parameter of type '-1 | 1'. Additionally, the translated expression for the unary + operator would be considered as arithmetic expression with an incompatible left-hand side: > error TS2362: The left-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type. To resolve this issues, the implicit transformation should be avoided. This commit adds a new unary AST node to represent these expressions, allowing for more accurate type-checking. Fixes #20845 Fixes #36178 PR Close #37918
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@ -1656,7 +1656,7 @@ Reference "#a" is defined several times ("<div #a></div><div [ERROR ->]#a></div>
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expect(humanizeTplAst(parse('<div *ngIf="-1">', [ngIf]))).toEqual([
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[EmbeddedTemplateAst],
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[DirectiveAst, ngIf],
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[BoundDirectivePropertyAst, 'ngIf', '0 - 1'],
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[BoundDirectivePropertyAst, 'ngIf', '-1'],
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[ElementAst, 'div'],
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]);
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});
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