Jan 17, 2022 · Jan 9, 2022 · Jan 9, 2022 · Jan 9, 2022 · Jan 9, 2022 · Jan 11, 2022
diff --git a/packages/type-utils/src/isTypeReadonly.ts b/packages/type-utils/src/isTypeReadonly.ts
  function checkIndexSignature(kind: ts.IndexKind): Readonlyness {
    const indexInfo = checker.getIndexInfoOfType(type, kind);
    if (indexInfo) {
      return indexInfo.isReadonly
        ? Readonlyness.Readonly
        : Readonlyness.Mutable;
      if (!indexInfo.isReadonly) {
        return Readonlyness.Mutable;
      }

      return isTypeReadonlyRecurser(
        checker,
        indexInfo.type,
        options,
        seenTypes,
      );
    }

    return Readonlyness.UnknownType;
  if (properties.length) {
    // ensure the properties are marked as readonly
    for (const property of properties) {
      if (
        !(
          isPropertyReadonlyInType(type, property.getEscapedName(), checker) ||
          (options.treatMethodsAsReadonly &&
            property.valueDeclaration !== undefined &&
            hasSymbol(property.valueDeclaration) &&
            isSymbolFlagSet(
              property.valueDeclaration.symbol,
              ts.SymbolFlags.Method,
            ))
        )
      ) {
        return Readonlyness.Mutable;
      if (options.treatMethodsAsReadonly) {
        if (
          property.valueDeclaration !== undefined &&
          hasSymbol(property.valueDeclaration) &&
          isSymbolFlagSet(
            property.valueDeclaration.symbol,
            ts.SymbolFlags.Method,
          )
        ) {
          continue;
        }

        const declarations = property.getDeclarations();
        const lastDeclaration =
          declarations !== undefined && declarations.length > 0
            ? declarations[declarations.length - 1]
            : undefined;
        if (
          lastDeclaration !== undefined &&
          hasSymbol(lastDeclaration) &&
          isSymbolFlagSet(lastDeclaration.symbol, ts.SymbolFlags.Method)
        ) {
          continue;
        }
      }

      if (isPropertyReadonlyInType(type, property.getEscapedName(), checker)) {
        continue;
      }

      return Readonlyness.Mutable;
    }

    // all properties were readonly
diff --git a/packages/type-utils/tests/isTypeReadonly.test.ts b/packages/type-utils/tests/isTypeReadonly.test.ts
          ])('handles non fully readonly sets and maps', runTests);
        });
      });

      describe('IndexSignature', () => {
        describe('is readonly', () => {
          const runTests = runTestIsReadonly;

          it.each([
            ['type Test = { readonly [key: string]: string };'],
            [
              'type Test = { readonly [key: string]: { readonly foo: readonly string[]; }; };',
            ],
          ])(
            'handles readonly PropertySignature inside a readonly IndexSignature',
            runTests,
          );
        });

        describe('is not readonly', () => {
          const runTests = runTestIsNotReadonly;

          it.each([
            ['type Test = { [key: string]: string };'],
            ['type Test = { readonly [key: string]: { foo: string[]; }; };'],
          ])(
            'handles mutable PropertySignature inside a readonly IndexSignature',
            runTests,
          );
        });
      });
    });

    describe('treatMethodsAsReadonly', () => {
Original file line number	Diff line number	Diff line change
Expand Up		@@ -107,9 +107,16 @@ function isTypeReadonlyObject(
		function checkIndexSignature(kind: ts.IndexKind): Readonlyness {
		const indexInfo = checker.getIndexInfoOfType(type, kind);
		if (indexInfo) {
		return indexInfo.isReadonly
		? Readonlyness.Readonly
		: Readonlyness.Mutable;
		if (!indexInfo.isReadonly) {
		return Readonlyness.Mutable;
		}

		return isTypeReadonlyRecurser(
		checker,
		indexInfo.type,
		options,
		seenTypes,
		);
		}

		return Readonlyness.UnknownType;
Expand All		@@ -119,20 +126,37 @@ function isTypeReadonlyObject(
		if (properties.length) {
		// ensure the properties are marked as readonly
		for (const property of properties) {
		if (
		!(
		isPropertyReadonlyInType(type, property.getEscapedName(), checker) \|\|
		(options.treatMethodsAsReadonly &&
		property.valueDeclaration !== undefined &&
		hasSymbol(property.valueDeclaration) &&
		isSymbolFlagSet(
		property.valueDeclaration.symbol,
		ts.SymbolFlags.Method,
		))
		)
		) {
		return Readonlyness.Mutable;
		if (options.treatMethodsAsReadonly) {
		if (
		property.valueDeclaration !== undefined &&
		hasSymbol(property.valueDeclaration) &&
		isSymbolFlagSet(
		property.valueDeclaration.symbol,
		ts.SymbolFlags.Method,
		)
		) {
		continue;
		}

		const declarations = property.getDeclarations();
		const lastDeclaration =
		declarations !== undefined && declarations.length > 0
		? declarations[declarations.length - 1]
		: undefined;
		if (
		lastDeclaration !== undefined &&
		hasSymbol(lastDeclaration) &&
		isSymbolFlagSet(lastDeclaration.symbol, ts.SymbolFlags.Method)
		) {
		continue;
		}
		}

		if (isPropertyReadonlyInType(type, property.getEscapedName(), checker)) {
		continue;
		}

		return Readonlyness.Mutable;
		}

		// all properties were readonly
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -109,6 +109,34 @@ describe('isTypeReadonly', () => {
		])('handles non fully readonly sets and maps', runTests);
		});
		});

		describe('IndexSignature', () => {
		describe('is readonly', () => {
		const runTests = runTestIsReadonly;

		it.each([
		['type Test = { readonly [key: string]: string };'],
		[
		'type Test = { readonly [key: string]: { readonly foo: readonly string[]; }; };',
		],
		])(
		'handles readonly PropertySignature inside a readonly IndexSignature',
		runTests,
		);
		});

		describe('is not readonly', () => {
		const runTests = runTestIsNotReadonly;

		it.each([
		['type Test = { [key: string]: string };'],
		['type Test = { readonly [key: string]: { foo: string[]; }; };'],
		])(
		'handles mutable PropertySignature inside a readonly IndexSignature',
		runTests,
		);
		});
		});
		});

		describe('treatMethodsAsReadonly', () => {
Expand Down