You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
99 lines
2.6 KiB
99 lines
2.6 KiB
# import/namespace |
|
|
|
Enforces names exist at the time they are dereferenced, when imported as a full namespace (i.e. `import * as foo from './foo'; foo.bar();` will report if `bar` is not exported by `./foo`.). |
|
|
|
Will report at the import declaration if there are _no_ exported names found. |
|
|
|
Also, will report for computed references (i.e. `foo["bar"]()`). |
|
|
|
Reports on assignment to a member of an imported namespace. |
|
|
|
Note: for packages, the plugin will find exported names |
|
from [`jsnext:main`], if present in `package.json`. |
|
Redux's npm module includes this key, and thereby is lintable, for example. |
|
|
|
A module path that is [ignored] or not [unambiguously an ES module] will not be reported when imported. |
|
|
|
[ignored]: ../README.md#importignore |
|
[unambiguously an ES module]: https://github.com/bmeck/UnambiguousJavaScriptGrammar |
|
|
|
## Rule Details |
|
|
|
Currently, this rule does not check for possible |
|
redefinition of the namespace in an intermediate scope. Adherence to the ESLint |
|
`no-shadow` rule for namespaces will prevent this from being a problem. |
|
|
|
For [ES7], reports if an exported namespace would be empty (no names exported from the referenced module.) |
|
|
|
Given: |
|
```js |
|
// @module ./named-exports |
|
export const a = 1 |
|
const b = 2 |
|
export { b } |
|
|
|
const c = 3 |
|
export { c as d } |
|
|
|
export class ExportedClass { } |
|
|
|
// ES7 |
|
export * as deep from './deep' |
|
``` |
|
and: |
|
```js |
|
// @module ./deep |
|
export const e = "MC2" |
|
``` |
|
|
|
See what is valid and reported: |
|
|
|
```js |
|
// @module ./foo |
|
import * as names from './named-exports' |
|
|
|
function great() { |
|
return names.a + names.b // so great https://youtu.be/ei7mb8UxEl8 |
|
} |
|
|
|
function notGreat() { |
|
doSomethingWith(names.c) // Reported: 'c' not found in imported namespace 'names'. |
|
|
|
const { a, b, c } = names // also reported, only for 'c' |
|
} |
|
|
|
// also tunnels through re-exported namespaces! |
|
function deepTrouble() { |
|
doSomethingWith(names.deep.e) // fine |
|
doSomethingWith(names.deep.f) // Reported: 'f' not found in deeply imported namespace 'names.deep'. |
|
} |
|
|
|
``` |
|
|
|
### Options |
|
|
|
#### `allowComputed` |
|
|
|
Defaults to `false`. When false, will report the following: |
|
|
|
```js |
|
/*eslint import/namespace: [2, { allowComputed: false }]*/ |
|
import * as a from './a' |
|
|
|
function f(x) { |
|
return a[x] // Unable to validate computed reference to imported namespace 'a'. |
|
} |
|
``` |
|
|
|
When set to `true`, the above computed namespace member reference is allowed, but |
|
still can't be statically analyzed any further. |
|
|
|
## Further Reading |
|
|
|
- Lee Byron's [ES7] export proposal |
|
- [`import/ignore`] setting |
|
- [`jsnext:main`](Rollup) |
|
|
|
[ES7]: https://github.com/leebyron/ecmascript-more-export-from |
|
[`import/ignore`]: ../../README.md#importignore |
|
[`jsnext:main`]: https://github.com/rollup/rollup/wiki/jsnext:main
|
|
|