mirror of
https://github.com/jfmengels/elm-review.git
synced 2024-11-05 05:31:12 +03:00
126 lines
2.7 KiB
Elm
126 lines
2.7 KiB
Elm
module NoListLiteralsConcat exposing (rule)
|
|
|
|
{-|
|
|
|
|
@docs rule
|
|
|
|
-}
|
|
|
|
import Elm.Syntax.Expression as Expression exposing (Expression)
|
|
import Elm.Syntax.Node as Node exposing (Node)
|
|
import Elm.Syntax.Range exposing (Range)
|
|
import Review.Rule as Rule exposing (Error, Rule)
|
|
|
|
|
|
{-| Reports when an operation on lists could be simplified to a single literal list.
|
|
|
|
config =
|
|
[ NoListLiteralsConcat.rule
|
|
]
|
|
|
|
|
|
## Fail
|
|
|
|
_ =
|
|
[ 1, 2, 3 ] ++ [ 4, mysteryNumber, 6 ]
|
|
|
|
_ =
|
|
List.concat
|
|
[ [ 1, 2, 3 ]
|
|
, [ 4, mysteryNumber, 6 ]
|
|
]
|
|
|
|
_ =
|
|
List.concat
|
|
[ [ 1, 2, 3 ]
|
|
]
|
|
|
|
_ =
|
|
1 :: [ 2, 3 ]
|
|
|
|
_ =
|
|
[] ++ list
|
|
|
|
_ =
|
|
list ++ []
|
|
|
|
|
|
## Success
|
|
|
|
_ =
|
|
[ 1, 2, 3, 4, mysteryNumber, 6 ]
|
|
|
|
_ =
|
|
[ 1, 2, 3 ] ++ list ++ [ 4, mysteryNumber, 6 ]
|
|
|
|
_ =
|
|
List.concat
|
|
[ [ 1, 2, 3 ]
|
|
, list
|
|
, [ 4, mysteryNumber, 6 ]
|
|
]
|
|
|
|
|
|
## Try it out
|
|
|
|
You can try this rule out by running the following command:
|
|
|
|
```bash
|
|
elm-review --template jfmengels/elm-review-simplification/example --rules NoListLiteralsConcat
|
|
```
|
|
|
|
-}
|
|
rule : Rule
|
|
rule =
|
|
Rule.newModuleRuleSchema "NoListLiteralsConcat" ()
|
|
|> Rule.withSimpleExpressionVisitor expressionVisitor
|
|
|> Rule.fromModuleRuleSchema
|
|
|
|
|
|
error : Range -> Error {}
|
|
error range =
|
|
Rule.error
|
|
{ message = "Expression could be simplified to be a single List"
|
|
, details = [ "Try moving all the elements into a single list." ]
|
|
}
|
|
range
|
|
|
|
|
|
expressionVisitor : Node Expression -> List (Error {})
|
|
expressionVisitor node =
|
|
case Node.value node of
|
|
Expression.OperatorApplication "++" _ (Node.Node _ (Expression.ListExpr _)) (Node.Node _ (Expression.ListExpr _)) ->
|
|
[ error (Node.range node) ]
|
|
|
|
Expression.OperatorApplication "++" _ (Node.Node range (Expression.ListExpr [])) _ ->
|
|
[ error range ]
|
|
|
|
Expression.OperatorApplication "++" _ _ (Node.Node range (Expression.ListExpr [])) ->
|
|
[ error range ]
|
|
|
|
Expression.OperatorApplication "::" _ _ (Node.Node _ (Expression.ListExpr _)) ->
|
|
[ error (Node.range node) ]
|
|
|
|
Expression.Application [ Node.Node _ (Expression.FunctionOrValue [ "List" ] "concat"), Node.Node _ (Expression.ListExpr list) ] ->
|
|
if List.length list < 2 then
|
|
[ error (Node.range node) ]
|
|
|
|
else if List.all isListLiteral list then
|
|
[ error (Node.range node) ]
|
|
|
|
else
|
|
[]
|
|
|
|
_ ->
|
|
[]
|
|
|
|
|
|
isListLiteral : Node Expression -> Bool
|
|
isListLiteral node =
|
|
case Node.value node of
|
|
Expression.ListExpr _ ->
|
|
True
|
|
|
|
_ ->
|
|
False
|