Oct 23, 2025 · Oct 23, 2025
diff --git a/packages/scope-manager/src/scope/ScopeBase.ts b/packages/scope-manager/src/scope/ScopeBase.ts
 } from '../referencer/Reference';
 import { Variable } from '../variable';
 import { ScopeType } from './ScopeType';
 import { ImplicitLibVariable } from '../variable/ImplicitLibVariable';

 /**
 * Test if scope is strict
    }
    // variable exists on the scope

    // implicit lib variables should always be resolved statically
    if (variable instanceof ImplicitLibVariable) {
      return true;
    }

    // in module mode, we can statically resolve everything, regardless of its decl type
    if (scopeManager.isModule()) {
      return true;
          : nameOrVariable;
      set.set(name, variable);
      variables.push(variable);
    } else if (
      variable instanceof ImplicitLibVariable &&
      nameOrVariable instanceof ImplicitLibVariable
    ) {
      variable.isTypeVariable ||= nameOrVariable.isTypeVariable;
      variable.isValueVariable ||= nameOrVariable.isValueVariable;
    }

    if (def) {
diff --git a/packages/scope-manager/src/variable/ImplicitLibVariable.ts b/packages/scope-manager/src/variable/ImplicitLibVariable.ts
  /**
   * `true` if the variable is valid in a type context, false otherwise
   */
  publicreadonlyisTypeVariable: boolean;
  public isTypeVariable: boolean;

  /**
   * `true` if the variable is valid in a value context, false otherwise
   */
  publicreadonlyisValueVariable: boolean;
  public isValueVariable: boolean;

  public constructor(
    scope: Scope,
diff --git a/packages/scope-manager/tests/lib.test.ts b/packages/scope-manager/tests/lib.test.ts
      });
    }).toThrow('invalid+lib');
  });

  it('should merge duplicate variable definitions with different properties', () => {
    // taken from https://github.com/eslint/eslint/pull/19695/files#diff-a82bd73f60a34f613614f30df6bbb802c8d9294735b8f9ffe8e7a8ce5d51629aR3841
    const { scopeManager } = parseAndAnalyze(
      'Object; Boolean; String; Math; Date; Array; Map; Set;',
      {
        lib: ['es2015'],
      },
    );

    const variables = scopeManager.variables;
    const globalVariables = variables.filter(
      v =>
        v.name === 'Object' ||
        v.name === 'Boolean' ||
        v.name === 'String' ||
        v.name === 'Math' ||
        v.name === 'Date' ||
        v.name === 'Array' ||
        v.name === 'Map' ||
        v.name === 'Set',
    );
    expect(globalVariables).toHaveLength(8);

    for (const globalVariable of globalVariables) {
      expect(globalVariable.references).toHaveLength(1);
    }
  });
 });
Original file line number	Diff line number	Diff line change
Expand Up		@@ -21,6 +21,7 @@ import {
		} from '../referencer/Reference';
		import { Variable } from '../variable';
		import { ScopeType } from './ScopeType';
		import { ImplicitLibVariable } from '../variable/ImplicitLibVariable';

		/**
		* Test if scope is strict
Expand DownExpand Up		@@ -325,6 +326,11 @@ export abstract class ScopeBase<
		}
		// variable exists on the scope

		// implicit lib variables should always be resolved statically
		if (variable instanceof ImplicitLibVariable) {
		return true;
		}

		// in module mode, we can statically resolve everything, regardless of its decl type
		if (scopeManager.isModule()) {
		return true;
Expand DownExpand Up		@@ -390,6 +396,12 @@ export abstract class ScopeBase<
		: nameOrVariable;
		set.set(name, variable);
		variables.push(variable);
		} else if (
		variable instanceof ImplicitLibVariable &&
		nameOrVariable instanceof ImplicitLibVariable
		) {
		variable.isTypeVariable \|\|= nameOrVariable.isTypeVariable;
		variable.isValueVariable \|\|= nameOrVariable.isValueVariable;
		}

		if (def) {
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -25,12 +25,12 @@ export class ImplicitLibVariable
		/**
		* `true` if the variable is valid in a type context, false otherwise
		*/
		publicreadonlyisTypeVariable: boolean;
		public isTypeVariable: boolean;

		/**
		* `true` if the variable is valid in a value context, false otherwise
		*/
		publicreadonlyisValueVariable: boolean;
		public isValueVariable: boolean;

		public constructor(
		scope: Scope,
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -126,4 +126,32 @@ describe('implicit lib definitions', () => {
		});
		}).toThrow('invalid+lib');
		});

		it('should merge duplicate variable definitions with different properties', () => {
		// taken from https://github.com/eslint/eslint/pull/19695/files#diff-a82bd73f60a34f613614f30df6bbb802c8d9294735b8f9ffe8e7a8ce5d51629aR3841
		const { scopeManager } = parseAndAnalyze(
		'Object; Boolean; String; Math; Date; Array; Map; Set;',
		{
		lib: ['es2015'],
		},
		);

		const variables = scopeManager.variables;
		const globalVariables = variables.filter(
		v =>
		v.name === 'Object' \|\|
		v.name === 'Boolean' \|\|
		v.name === 'String' \|\|
		v.name === 'Math' \|\|
		v.name === 'Date' \|\|
		v.name === 'Array' \|\|
		v.name === 'Map' \|\|
		v.name === 'Set',
		);
		expect(globalVariables).toHaveLength(8);

		for (const globalVariable of globalVariables) {
		expect(globalVariable.references).toHaveLength(1);
		}
		});
		});