Add Exception import when needed.

generator/dead-code-review/src/Pages/Review/DeadCodeEliminateData.elm

@@ -7,6 +7,7 @@ import Elm.Syntax.Expression as Expression exposing (Expression)
 import Elm.Syntax.Import exposing (Import)
 import Elm.Syntax.ModuleName exposing (ModuleName)
 import Elm.Syntax.Node as Node exposing (Node)
+import Elm.Syntax.Range exposing (Range)
 import Review.Fix
 import Review.ModuleNameLookupTable as ModuleNameLookupTable exposing (ModuleNameLookupTable)
 import Review.Rule as Rule exposing (Error, Rule)
@@ -15,6 +16,7 @@ import Review.Rule as Rule exposing (Error, Rule)
 type alias Context =
     { lookupTable : ModuleNameLookupTable
     , importContext : Dict (List String) ImportContext
+    , firstImport : Maybe Range
     }
 
 
@@ -66,15 +68,39 @@ rule =
         |> Rule.withExpressionEnterVisitor expressionVisitor
         |> Rule.withDeclarationEnterVisitor declarationVisitor
         |> Rule.withImportVisitor importVisitor
+        |> Rule.withFinalModuleEvaluation finalEvaluation
         |> Rule.fromModuleRuleSchema
 
 
+finalEvaluation : Context -> List (Rule.Error {})
+finalEvaluation context =
+    case Dict.get [ "Exception" ] context.importContext of
+        Nothing ->
+            let
+                importAddRange : { start : { row : Int, column : Int }, end : { row : Int, column : Int } }
+                importAddRange =
+                    context.firstImport |> Maybe.withDefault { start = { row = 0, column = 0 }, end = { row = 0, column = 0 } }
+            in
+            [ Rule.errorWithFix
+                { message = "Codemod"
+                , details = [ "" ]
+                }
+                importAddRange
+                [ Review.Fix.insertAt importAddRange.end "\nimport Exception\n"
+                ]
+            ]
+
+        _ ->
+            []
+
+
 initialContext : Rule.ContextCreator () Context
 initialContext =
     Rule.initContextCreator
         (\lookupTable () ->
             { lookupTable = lookupTable
             , importContext = Dict.empty
+            , firstImport = Nothing
             }
         )
         |> Rule.withModuleNameLookupTable
@@ -91,6 +117,7 @@ importVisitor node context =
     , { context
         | importContext =
             context.importContext |> Dict.insert key value
+        , firstImport = context.firstImport |> Maybe.withDefault (Node.range node) |> Just
       }
     )
 

generator/dead-code-review/tests/Pages/Review/DeadCodeEliminateDataTest.elm

@@ -15,6 +15,7 @@ all =
 import Server.Request as Request
 
 import BackendTask exposing (BackendTask)
+import Exception
 import RouteBuilder exposing (Page, StaticPayload, single)
 import Pages.PageUrl exposing (PageUrl)
 import Pages.Url
@@ -69,6 +70,7 @@ data =
 import Server.Request as Request
 
 import BackendTask exposing (BackendTask)
+import Exception
 import RouteBuilder exposing (Page, StaticPayload, single)
 import Pages.PageUrl exposing (PageUrl)
 import Pages.Url
@@ -113,6 +115,7 @@ data =
                 """module Route.Index exposing (Data, Model, Msg, route)
 
 import Server.Request as Request
+import Exception
 import BackendTask as DS
 import RouteBuilder exposing (Page, StaticPayload, single)
 import Pages.PageUrl exposing (PageUrl)
@@ -166,6 +169,7 @@ data =
                                 """module Route.Index exposing (Data, Model, Msg, route)
 
 import Server.Request as Request
+import Exception
 import BackendTask as DS
 import RouteBuilder exposing (Page, StaticPayload, single)
 import Pages.PageUrl exposing (PageUrl)
@@ -213,6 +217,7 @@ data =
 import Server.Request as Request
 
 import BackendTask exposing (BackendTask)
+import Exception
 import RouteBuilder exposing (Page, StaticPayload)
 import Pages.PageUrl exposing (PageUrl)
 import Pages.Url
@@ -267,6 +272,7 @@ data =
 import Server.Request as Request
 
 import BackendTask exposing (BackendTask)
+import Exception
 import RouteBuilder exposing (Page, StaticPayload)
 import Pages.PageUrl exposing (PageUrl)
 import Pages.Url
@@ -312,6 +318,7 @@ data =
                 """module Route.Login exposing (Data, Model, Msg, route)
 
 import Server.Request as Request
+import Exception
 
 type alias Model =
     {}
@@ -348,6 +355,7 @@ route =
                                 """module Route.Login exposing (Data, Model, Msg, route)
 
 import Server.Request as Request
+import Exception
 
 type alias Model =
     {}
@@ -382,6 +390,7 @@ route =
                                 """module Route.Login exposing (Data, Model, Msg, route)
 
 import Server.Request as Request
+import Exception
 
 type alias Model =
     {}
@@ -410,6 +419,7 @@ route =
                 """module Route.Login exposing (Data, Model, Msg, route)
 
 import Server.Request
+import Exception
 
 type alias Model =
     {}
@@ -446,6 +456,7 @@ route =
                                 """module Route.Login exposing (Data, Model, Msg, route)
 
 import Server.Request
+import Exception
 
 type alias Model =
     {}
@@ -480,6 +491,7 @@ route =
                                 """module Route.Login exposing (Data, Model, Msg, route)
 
 import Server.Request
+import Exception
 
 type alias Model =
     {}
@@ -508,6 +520,7 @@ route =
                 """module Route.Login exposing (Data, Model, Msg, route)
 
 import Server.Request as Request
+import Exception
 
 type alias Model =
     {}
@@ -536,6 +549,7 @@ route =
                 """module Route.Index exposing (Data, Model, Msg, route)
 
 import Server.Request as Request
+import Exception
 
 import BackendTask exposing (BackendTask)
 import RouteBuilder exposing (Page, StaticPayload)
@@ -583,6 +597,7 @@ data =
                 """module Shared exposing (Data, Model, Msg, template)
 
 import Server.Request as Request
+import Exception
 
 import Browser.Navigation
 import BackendTask
@@ -633,6 +648,7 @@ type alias Model =
                                 """module Shared exposing (Data, Model, Msg, template)
 
 import Server.Request as Request
+import Exception
 
 import Browser.Navigation
 import BackendTask