Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

fix(eslint-plugin): [strict-boolean-expressions] account for truthy literals #3236

Merged
merged 2 commits into from Apr 5, 2021
Merged

fix(eslint-plugin): [strict-boolean-expressions] account for truthy literals #3236

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
201ac41
fix(eslint-plugin): account for truthy literals in strict-boolean-exp…
Mar 29, 2021
42fae56
feat: accounted for options.allow*
Apr 5, 2021
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
49 changes: 34 additions & 15 deletions packages/eslint-plugin/src/rules/strict-boolean-expressions.ts
View file
Open in desktop
Expand Up @@ -308,8 +308,16 @@ export default util.createRule<Options, MessageId>({
return;
}

// Known edge case: truthy primitives and nullish values are always valid boolean expressions
if (
(options.allowNumber && is('nullish', 'truthy number')) ||
(options.allowString && is('nullish', 'truthy string'))
) {
return;
}

// string
if (is('string')) {
if (is('string') || is('truthy string')) {
if (!options.allowString) {
if (isLogicalNegationExpression(node.parent!)) {
// if (!string)
Expand Down Expand Up @@ -458,7 +466,7 @@ export default util.createRule<Options, MessageId>({
}

// number
if (is('number')) {
if (is('number') || is('truthy number')) {
if (!options.allowNumber) {
if (isArrayLengthExpression(node, typeChecker, parserServices)) {
if (isLogicalNegationExpression(node.parent!)) {
Expand Down Expand Up @@ -701,7 +709,9 @@ export default util.createRule<Options, MessageId>({
| 'nullish'
| 'boolean'
| 'string'
| 'truthy string'
| 'number'
| 'truthy number'
| 'object'
| 'any'
| 'never';
Expand Down Expand Up @@ -731,21 +741,30 @@ export default util.createRule<Options, MessageId>({
variantTypes.add('boolean');
}

if (
types.some(type => tsutils.isTypeFlagSet(type, ts.TypeFlags.StringLike))
) {
variantTypes.add('string');
const strings = types.filter(type =>
tsutils.isTypeFlagSet(type, ts.TypeFlags.StringLike),
);

if (strings.length) {
if (strings.some(type => type.isStringLiteral() && type.value !== '')) {
variantTypes.add('truthy string');
} else {
variantTypes.add('string');
}
}

if (
types.some(type =>
tsutils.isTypeFlagSet(
type,
ts.TypeFlags.NumberLike | ts.TypeFlags.BigIntLike,
),
)
) {
variantTypes.add('number');
const numbers = types.filter(type =>
tsutils.isTypeFlagSet(
type,
ts.TypeFlags.NumberLike | ts.TypeFlags.BigIntLike,
),
);
if (numbers.length) {
if (numbers.some(type => type.isNumberLiteral() && type.value !== 0)) {
variantTypes.add('truthy number');
} else {
variantTypes.add('number');
}
}

if (
Expand Down
51 changes: 51 additions & 0 deletions packages/eslint-plugin/tests/rules/strict-boolean-expressions.test.ts
View file
Open in desktop
Expand Up @@ -133,6 +133,57 @@ if (x) {
tsconfigRootDir: path.join(rootPath, 'unstrict'),
},
},

`
function f(arg: 'a' | null) {
if (arg) console.log(arg);
}
`,
`
function f(arg: 'a' | 'b' | null) {
if (arg) console.log(arg);
}
`,
{
code: `
declare const x: 1 | null;
declare const y: 1;
if (x) {
}
if (y) {
}
`,
options: [
{
allowNumber: true,
},
],
},
`
function f(arg: 1 | null) {
if (arg) console.log(arg);
}
`,
`
function f(arg: 1 | 2 | null) {
if (arg) console.log(arg);
}
`,
{
code: `
declare const x: 'a' | null;
declare const y: 'a';
if (x) {
}
if (y) {
}
`,
options: [
{
allowString: true,
},
],
},
],

invalid: [
Expand Down