Rewrite explicit-length-check rule (#938)

docs/rules/explicit-length-check.md

@@ -1,61 +1,123 @@
 # Enforce explicitly comparing the `length` property of a value
 
-Enforce explicitly checking the length of a value array in an `if` condition, rather than checking the truthiness of the length, and enforce comparison style.
+Enforce explicitly checking the length of an array in an `if` condition or ternary and enforce the comparison style.
 
-This rule is partly fixable.
+This rule is fixable.
+
+## Zero comparisons
+
+Enforce comparison with `=== 0` when checking for zero length.
 
 ### Fail
 
 ```js
-if (string.length) {}
-if (array.length) {}
-if (!array.length) {}
-if (array.length !== 0) {}
+if (!foo.length) {}
+```
+
+```js
+if (foo.length == 0) {}
+```
+
+```js
+if (foo.length < 1) {}
+```
+
+```js
+if (0 === foo.length) {}
+```
+
+```js
+if (0 == foo.length) {}
+```
+
+```js
+if (1 > foo.length) {}
+```
+
+```js
+// Negative style is forbid too
+if (!(foo.length > 0)) {}
 ```
 
 ### Pass
 
 ```js
-if (string.length > 0) {}
-if (array.length > 0) {}
-if (array.length === 0) {}
+if (foo.length === 0) {}
 ```
 
+```js
+const unicorn = foo.length === 0 ? 1 : 2;
+```
 
-## Zero comparisons
+## Non-zero comparisons
 
-Enforce comparison with `=== 0` when checking for zero length.
+Enforce comparison with `> 0` when checking for non-zero length.
 
 ### Fail
 
 ```js
-if (string.length < 1) {}
+if (foo.length !== 0) {}
+```
+
+```js
+if (foo.length != 0) {}
+```
+
+```js
+if (foo.length >= 1) {}
+```
+
+```js
+if (0 !== foo.length) {}
+```
+
+```js
+if (0 != foo.length) {}
+```
+
+```js
+if (0 < foo.length) {}
+```
+
+```js
+if (1 <= foo.length) {}
+```
+
+```js
+// Negative style is forbid too
+if (!(foo.length === 0)) {}
 ```
 
 ### Pass
 
 ```js
-if (array.length === 0) {}
+if (foo.length > 0) {}
 ```
 
+```js
+const unicorn = foo.length > 0 ? 1 : 2;
+```
 
-## Non-zero comparisons
+### Options
 
 You can define your preferred way of checking non-zero length by providing a `non-zero` option (`greater-than` by default):
 
 ```js
 {
-	'unicorn/explicit-length-check': ['error', {
-		'non-zero': 'not-equal'
-	}]
+	'unicorn/explicit-length-check': [
+		'error',
+		{
+			'non-zero': 'not-equal'
+		}
+	]
 }
 ```
 
 The `non-zero` option can be configured with one of the following:
 
 - `greater-than` (default)
-	- Enforces non-zero to be checked with: `array.length > 0`
+	- Enforces non-zero to be checked with: `foo.length > 0`
 - `not-equal`
-	- Enforces non-zero to be checked with: `array.length !== 0`
+	- Enforces non-zero to be checked with: `foo.length !== 0`
 - `greater-than-or-equal`
-	- Enforces non-zero to be checked with: `array.length >= 1`
+	- Enforces non-zero to be checked with: `foo.length >= 1`

readme.md

@@ -111,7 +111,7 @@ Configure it in `package.json`.
 - [error-message](docs/rules/error-message.md) - Enforce passing a `message` value when creating a built-in error.
 - [escape-case](docs/rules/escape-case.md) - Require escape sequences to use uppercase values. *(fixable)*
 - [expiring-todo-comments](docs/rules/expiring-todo-comments.md) - Add expiration conditions to TODO comments.
-- [explicit-length-check](docs/rules/explicit-length-check.md) - Enforce explicitly comparing the `length` property of a value. *(partly fixable)*
+- [explicit-length-check](docs/rules/explicit-length-check.md) - Enforce explicitly comparing the `length` property of a value. *(fixable)*
 - [filename-case](docs/rules/filename-case.md) - Enforce a case style for filenames.
 - [import-index](docs/rules/import-index.md) - Enforce importing index files with `.`. *(fixable)*
 - [import-style](docs/rules/import-style.md) - Enforce specific import styles per module.