Add rule (Install.Import) to add an import statement for a given modu…

…le in a given module.

s

preview/src/ReviewConfig.elm

@@ -16,19 +16,22 @@ import Install.FieldInTypeAlias
 import Install.Function
 import Install.Initializer
 import Install.TypeVariant
+import Install.Import
 import Review.Rule exposing (Rule)
 
 
 config : List Rule
 config =
-    [ Install.TypeVariant.makeRule "Types" "ToBackend" "CounterReset"
-    , Install.TypeVariant.makeRule "Types" "FrontendMsg" "Reset"
-    , Install.ClauseInCase.init "Frontend" "update" "Reset" "( { model | counter = 0 }, sendToBackend CounterReset )"
-        |> Install.ClauseInCase.withInsertAfter "Increment"
-        |> Install.ClauseInCase.makeRule
-    , Install.ClauseInCase.init "Backend" "updateFromFrontend" "CounterReset" "( { model | counter = 0 }, broadcast (CounterNewValue 0 clientId) )"
-        |> Install.ClauseInCase.makeRule
-    , Install.Function.init [ "Frontend" ] "view" viewFunction |> Install.Function.makeRule
+    [ --Install.TypeVariant.makeRule "Types" "ToBackend" "CounterReset"
+          --, Install.TypeVariant.makeRule "Types" "FrontendMsg" "Reset"
+          --, Install.ClauseInCase.init "Frontend" "update" "Reset" "( { model | counter = 0 }, sendToBackend CounterReset )"
+          --    |> Install.ClauseInCase.withInsertAfter "Increment"
+          --    |> Install.ClauseInCase.makeRule
+          --, Install.ClauseInCase.init "Backend" "updateFromFrontend" "CounterReset" "( { model | counter = 0 }, broadcast (CounterNewValue 0 clientId) )"
+          --    |> Install.ClauseInCase.makeRule
+          --, Install.Function.init [ "Frontend" ] "view" viewFunction |> Install.Function.makeRule
+    --
+     Install.Import.makeRule "Frontend" "Foo.Bar" "add: import module Foo."
     ]
 
 

src/Install/Import.elm

@@ -0,0 +1,83 @@
+module Install.Import exposing (..)
+
+import Elm.Syntax.Import exposing (Import)
+import Elm.Syntax.ModuleName exposing (ModuleName)
+import Elm.Syntax.Node as Node exposing (Node(..))
+import Elm.Syntax.Range as Range exposing (Range)
+import Review.Fix as Fix exposing (Fix)
+import Review.Rule as Rule exposing (Error, Rule)
+import Set exposing (Set)
+
+
+{-| Custom error message to be displayed when running `elm-review --fix` or `elm-review --fix-all`
+-}
+type CustomError
+    = CustomError { message : String, details : List String }
+
+
+{-| Create a rule that adds an import for a given module in a given module. For example:
+
+     Install.Import.makeRule "Frontend" "Foo.Bar" "add: import module Foo."
+
+-}
+makeRule : String -> String -> String -> Rule
+makeRule hostModuleName importedModuleName customErrorMessage =
+    let
+        hostModuleNameList =
+            String.split "." hostModuleName
+
+        importedModuleNameList =
+            String.split "." importedModuleName
+    in
+    Rule.newModuleRuleSchemaUsingContextCreator "Install.Import" initialContext
+        |> Rule.withImportVisitor (importVisitor hostModuleNameList importedModuleNameList)
+        |> Rule.withFinalModuleEvaluation (finalEvaluation hostModuleNameList importedModuleNameList)
+        |> Rule.providesFixesForModuleRule
+        |> Rule.fromModuleRuleSchema
+
+
+type alias Context =
+    { moduleName : ModuleName
+    , moduleWasImported : Bool
+    , lastNodeRange : Range
+    }
+
+
+initialContext : Rule.ContextCreator () Context
+initialContext =
+    Rule.initContextCreator
+        (\moduleName () -> { moduleName = moduleName, moduleWasImported = False, lastNodeRange = Range.empty })
+        |> Rule.withModuleName
+
+
+importVisitor : List String -> List String -> Node Import -> Context -> ( List (Error {}), Context )
+importVisitor hostModuleNameList importedModuleNameList node context =
+    case Node.value node |> .moduleName |> Node.value of
+        currentModuleName ->
+            if currentModuleName == importedModuleNameList && hostModuleNameList == context.moduleName then
+                ( [], { context | moduleWasImported = True, lastNodeRange = Node.range node } )
+
+            else
+                ( [], { context | lastNodeRange = Node.range node } )
+
+
+finalEvaluation : List String -> List String -> Context -> List (Rule.Error {})
+finalEvaluation hostModuleNameList moduleToImport context =
+    let
+        _ =
+            Debug.log "CONTEXT" context
+    in
+    if context.moduleWasImported == False && hostModuleNameList == context.moduleName then
+        fixError moduleToImport context
+
+    else
+        []
+
+
+fixError : List String -> Context -> List (Error {})
+fixError moduleToImport context =
+    [ Rule.errorWithFix
+        { message = "moduleToImport: \"" ++ String.join "." moduleToImport ++ "\"", details = [ "" ] }
+        context.lastNodeRange
+        [ Fix.insertAt { row = context.lastNodeRange.end.row + 1, column = context.lastNodeRange.end.column } ("import " ++ String.join "." moduleToImport) ]
+    ]