Jan 28, 2024 · Jan 16, 2024 · Jan 16, 2024 · Jan 24, 2024 · Jan 24, 2024 · Jan 24, 2024
diff --git a/packages/eslint-plugin/src/rules/prefer-nullish-coalescing.ts b/packages/eslint-plugin/src/rules/prefer-nullish-coalescing.ts
  getTypeFlags,
  isLogicalOrOperator,
  isNodeEqual,
  isNullableType,
  isNullLiteral,
  isTypeFlagSet,
  isUndefinedIdentifier,
  nullThrows,
  NullThrowsReasons,
      ): void {
        const tsNode = parserServices.esTreeNodeToTSNodeMap.get(node);
        const type = checker.getTypeAtLocation(tsNode.left);
        if (!isNullableType(type)) {
        if (!isTypeFlagSet(type, ts.TypeFlags.Null | ts.TypeFlags.Undefined)) {
          return;
        }

diff --git a/packages/eslint-plugin/tests/rules/prefer-nullish-coalescing.test.ts b/packages/eslint-plugin/tests/rules/prefer-nullish-coalescing.test.ts
      `,
      options: [{ ignorePrimitives: true }],
    })),
    `
      declare const x: any;
      declare const y: number;
      x || y;
    `,
    `
      declare const x: unknown;
      declare const y: number;
      x || y;
    `,
    `
      declare const x: never;
      declare const y: number;
      x || y;
    `,
  ],
  invalid: [
    ...nullishTypeInvalidTest((nullish, type) => ({
Original file line number	Diff line number	Diff line change
Expand Up		@@ -10,8 +10,8 @@ import {
		getTypeFlags,
		isLogicalOrOperator,
		isNodeEqual,
		isNullableType,
		isNullLiteral,
		isTypeFlagSet,
		isUndefinedIdentifier,
		nullThrows,
		NullThrowsReasons,
Expand DownExpand Up		@@ -309,7 +309,7 @@ export default createRule<Options, MessageIds>({
		): void {
		const tsNode = parserServices.esTreeNodeToTSNodeMap.get(node);
		const type = checker.getTypeAtLocation(tsNode.left);
		if (!isNullableType(type)) {
		if (!isTypeFlagSet(type, ts.TypeFlags.Null \| ts.TypeFlags.Undefined)) {
Copy link Member JoshuaKGoldbergJan 24, 2024 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. @Josh-Cena threading#8262 (comment): I'm good with this solution 👍 I wonder though, shouldn't we recommend switching to nullish coalescing for any/unknown too, with an option to turn that off, just like primitives? Because any/unknown are also nullable, it doesn't make no sense to use nullish coalescing. Hmm, good question. I think if the type is explicitly not known then it'd be risky to suggest making any concrete changes to its handling. I'd be in support of this as an opt-in in for v6 andmaybe an opt-out for v7.
		return;
		}

Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -222,6 +222,21 @@ x \|\| y;
		`,
		options: [{ ignorePrimitives: true }],
		})),
		`
		declare const x: any;
		declare const y: number;
		x \|\| y;
		`,
		`
		declare const x: unknown;
		declare const y: number;
		x \|\| y;
		`,
		`
		declare const x: never;
		declare const y: number;
		x \|\| y;
		`,
auvred marked this conversation as resolved. Show resolvedHide resolved
		],
		invalid: [
		...nullishTypeInvalidTest((nullish, type) => ({
Expand Down