Add withModuleDocumentation

src/Review/Rule.elm

@@ -14,7 +14,7 @@ module Review.Rule exposing
     , withFinalModuleEvaluation
     , withElmJsonModuleVisitor, withReadmeModuleVisitor, withDependenciesModuleVisitor
     , ProjectRuleSchema, newProjectRuleSchema, fromProjectRuleSchema, withModuleVisitor, withModuleContext, withModuleContextUsingContextCreator, withElmJsonProjectVisitor, withReadmeProjectVisitor, withDependenciesProjectVisitor, withFinalProjectEvaluation, withContextFromImportedModules
-    , ContextCreator, initContextCreator, withModuleName, withModuleNameNode, withIsInSourceDirectories, withFilePath, withModuleNameLookupTable, withModuleKey, withSourceCodeExtractor, withFullAst
+    , ContextCreator, initContextCreator, withModuleName, withModuleNameNode, withIsInSourceDirectories, withFilePath, withModuleNameLookupTable, withModuleKey, withSourceCodeExtractor, withFullAst, withModuleDocumentation
     , Metadata, withMetadata, moduleNameFromMetadata, moduleNameNodeFromMetadata, isInSourceDirectories
     , Error, error, errorWithFix, ModuleKey, errorForModule, errorForModuleWithFix, ElmJsonKey, errorForElmJson, errorForElmJsonWithFix, ReadmeKey, errorForReadme, errorForReadmeWithFix
     , globalError, configurationError
@@ -227,7 +227,7 @@ first, as they are in practice a simpler version of project rules.
 
 ## Requesting more information
 
-@docs ContextCreator, initContextCreator, withModuleName, withModuleNameNode, withIsInSourceDirectories, withFilePath, withModuleNameLookupTable, withModuleKey, withSourceCodeExtractor, withFullAst
+@docs ContextCreator, initContextCreator, withModuleName, withModuleNameNode, withIsInSourceDirectories, withFilePath, withModuleNameLookupTable, withModuleKey, withSourceCodeExtractor, withFullAst, withModuleDocumentation
 
 
 ### Requesting more information (DEPRECATED)
@@ -5311,6 +5311,28 @@ withFullAst (ContextCreator fn requested) =
         requested
 
 
+{-| Request the module documentation. Modules don't always have a documentation.
+When that is the case, the module documentation will be `Nothing`.
+
+    contextCreator : Rule.ContextCreator () Context
+    contextCreator =
+        Rule.initContextCreator
+            (\moduleDocumentation () ->
+                { moduleDocumentation = moduleDocumentation
+
+                -- ...other fields
+                }
+            )
+            |> Rule.withModuleDocumentation
+
+-}
+withModuleDocumentation : ContextCreator (Maybe (Node String)) (from -> to) -> ContextCreator from to
+withModuleDocumentation (ContextCreator fn requested) =
+    ContextCreator
+        (\data -> fn data (findModuleDocumentation data.ast))
+        requested
+
+
 {-| Request the [module key](#ModuleKey) for this module.
 
     rule : Rule

tests/Review/Rule/WithModuleDocumentationTest.elm

@@ -0,0 +1,66 @@
+module Review.Rule.WithModuleDocumentationTest exposing (all)
+
+import Elm.Syntax.Node as Node exposing (Node)
+import Review.Rule as Rule exposing (Rule)
+import Review.Test
+import Test exposing (Test, test)
+
+
+type alias Context =
+    { moduleDocumentation : Maybe (Node String)
+    }
+
+
+rule : Rule
+rule =
+    Rule.newModuleRuleSchemaUsingContextCreator "TestRule" initContext
+        |> Rule.withModuleDefinitionVisitor
+            (\node context ->
+                ( [ Rule.error
+                        { message =
+                            case context.moduleDocumentation of
+                                Just moduleDocumentation ->
+                                    Node.value moduleDocumentation
+
+                                Nothing ->
+                                    "MISSING DOCUMENTATION"
+                        , details = [ "No details" ]
+                        }
+                        (Node.range node)
+                  ]
+                , context
+                )
+            )
+        |> Rule.fromModuleRuleSchema
+
+
+initContext : Rule.ContextCreator () Context
+initContext =
+    Rule.initContextCreator
+        (\moduleDocumentation _ ->
+            { moduleDocumentation = moduleDocumentation
+            }
+        )
+        |> Rule.withModuleDocumentation
+
+
+all : Test
+all =
+    test "should pass the module documentation if there is one" <|
+        \() ->
+            """module ModuleName exposing (a)
+{-| module documentation
+-}
+
+{-| function doc
+-}
+a = 1
+"""
+                |> Review.Test.run rule
+                |> Review.Test.expectErrors
+                    [ Review.Test.error
+                        { message = "{-| module documentation\n-}"
+                        , details = [ "No details" ]
+                        , under = "module ModuleName exposing (a)"
+                        }
+                    ]