no-pipe-impure.md

@angular-eslint/no-pipe-impure

Disallows the declaration of impure pipes

• Type: suggestion

• 💡 Provides suggestions on how to fix issues (https://eslint.org/docs/developer-guide/working-with-rules#providing-suggestions)

Rule Options

The rule does not have any configuration options.

Usage Examples

The following examples are generated automatically from the actual unit tests within the plugin, so you can be assured that their behavior is accurate based on the current commit.

❌ - Toggle examples of incorrect code for this rule

Default Config

{
  "rules": {
    "@angular-eslint/no-pipe-impure": [
      "error"
    ]
  }
}

❌ Invalid Code

@Pipe({
  pure: false
  ~~~~~~~~~~~
})
class Test {}

---

Default Config

{
  "rules": {
    "@angular-eslint/no-pipe-impure": [
      "error"
    ]
  }
}

❌ Invalid Code

@Pipe({
  name: 'test',
  'pure': false,
  ~~~~~~~~~~~~~
})
class Test {}

---

Default Config

{
  "rules": {
    "@angular-eslint/no-pipe-impure": [
      "error"
    ]
  }
}

❌ Invalid Code

@Pipe({
  name: 'test',
  ['pure']: !true
  ~~~~~~~~~~~~~~~
})
class Test {}

---

Default Config

{
  "rules": {
    "@angular-eslint/no-pipe-impure": [
      "error"
    ]
  }
}

❌ Invalid Code

@Pipe({
  name: 'test',
  [`pure`]: false
  ~~~~~~~~~~~~~~~
})
class Test {}

---

✅ - Toggle examples of correct code for this rule

Default Config

{
  "rules": {
    "@angular-eslint/no-pipe-impure": [
      "error"
    ]
  }
}

✅ Valid Code

class Test {}

---

Default Config

{
  "rules": {
    "@angular-eslint/no-pipe-impure": [
      "error"
    ]
  }
}

✅ Valid Code

@Pipe()
class Test {}

---

Default Config

{
  "rules": {
    "@angular-eslint/no-pipe-impure": [
      "error"
    ]
  }
}

✅ Valid Code

@Pipe({})
class Test {}

---

Default Config

{
  "rules": {
    "@angular-eslint/no-pipe-impure": [
      "error"
    ]
  }
}

✅ Valid Code

const options = {};
@Pipe(options)
class Test {}

---

Default Config

{
  "rules": {
    "@angular-eslint/no-pipe-impure": [
      "error"
    ]
  }
}

✅ Valid Code

@Pipe({
  name: 'test',
})
class Test {}

---

Default Config

{
  "rules": {
    "@angular-eslint/no-pipe-impure": [
      "error"
    ]
  }
}

✅ Valid Code

@Pipe({
  pure: true
})
class Test {}

---

Default Config

{
  "rules": {
    "@angular-eslint/no-pipe-impure": [
      "error"
    ]
  }
}

✅ Valid Code

@Pipe({
  'pure': !0,
})
class Test {}

---

Default Config

{
  "rules": {
    "@angular-eslint/no-pipe-impure": [
      "error"
    ]
  }
}

✅ Valid Code

@Pipe({
  ['pure']: !!isPure(),
})
class Test {}

---

Default Config

{
  "rules": {
    "@angular-eslint/no-pipe-impure": [
      "error"
    ]
  }
}

✅ Valid Code

const pure = 'pure';
@Pipe({
  [pure]: false
})
class Test {}

---

Default Config

{
  "rules": {
    "@angular-eslint/no-pipe-impure": [
      "error"
    ]
  }
}

✅ Valid Code

const pure = false;
@Pipe({
  pure,
})
class Test {}

---

Default Config

{
  "rules": {
    "@angular-eslint/no-pipe-impure": [
      "error"
    ]
  }
}

✅ Valid Code

function isPure() {
  return false;
}

@Pipe({
  [`pure`]: isPure(),
})
class Test {}

---

Default Config

{
  "rules": {
    "@angular-eslint/no-pipe-impure": [
      "error"
    ]
  }
}

✅ Valid Code

@NgModule({
  bootstrap: [Foo]
})
class Test {}