useValidTypeof (since v1.0.0)
Diagnostic Category: lint/suspicious/useValidTypeof
Sources:
- Same as:
valid-typeof
This rule verifies the result of typeof $expr unary expressions is being compared to valid values, either string literals containing valid type names or other typeof expressions
Examples
Section titled ExamplesInvalid
Section titled Invalidtypeof foo === "strnig"code-block.js:1:16 lint/suspicious/useValidTypeof ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
✖ Invalid `typeof` comparison value
> 1 │ typeof foo === "strnig"
│ ^^^^^^^^
2 │
ℹ not a valid type name
typeof foo == "undefimed"code-block.js:1:15 lint/suspicious/useValidTypeof ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
✖ Invalid `typeof` comparison value
> 1 │ typeof foo == "undefimed"
│ ^^^^^^^^^^^
2 │
ℹ not a valid type name
typeof bar != "nunber"code-block.js:1:15 lint/suspicious/useValidTypeof ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
✖ Invalid `typeof` comparison value
> 1 │ typeof bar != "nunber"
│ ^^^^^^^^
2 │
ℹ not a valid type name
typeof bar !== "fucntion"code-block.js:1:16 lint/suspicious/useValidTypeof ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
✖ Invalid `typeof` comparison value
> 1 │ typeof bar !== "fucntion"
│ ^^^^^^^^^^
2 │
ℹ not a valid type name
typeof foo === undefinedcode-block.js:1:16 lint/suspicious/useValidTypeof FIXABLE ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
✖ Invalid `typeof` comparison value
> 1 │ typeof foo === undefined
│ ^^^^^^^^^
2 │
ℹ not a string literal
ℹ Unsafe fix: Compare the result of `typeof` with a valid type name
1 │ typeof·foo·===·"undefined"
│ + +
typeof bar == Objectcode-block.js:1:15 lint/suspicious/useValidTypeof FIXABLE ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
✖ Invalid `typeof` comparison value
> 1 │ typeof bar == Object
│ ^^^^^^
2 │
ℹ not a string literal
ℹ Unsafe fix: Compare the result of `typeof` with a valid type name
1 │ - typeof·bar·==·Object
1 │ + typeof·bar·==·"object"
2 2 │
typeof foo === bazcode-block.js:1:16 lint/suspicious/useValidTypeof ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
✖ Invalid `typeof` comparison value
> 1 │ typeof foo === baz
│ ^^^
2 │
ℹ not a string literal
typeof foo == 5code-block.js:1:15 lint/suspicious/useValidTypeof ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
✖ Invalid `typeof` comparison value
> 1 │ typeof foo == 5
│ ^
2 │
ℹ not a string literal
typeof foo == -5code-block.js:1:15 lint/suspicious/useValidTypeof ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
✖ Invalid `typeof` comparison value
> 1 │ typeof foo == -5
│ ^^
2 │
ℹ not a string literal
Valid
Section titled Validtypeof foo === "string"typeof bar == "undefined"typeof bar === typeof qux