Improve open definition check

Author: hojberg

src/Code/CodebaseTree.elm

@@ -326,9 +326,7 @@ viewNamespaceListing viewConfig openDefinitions expandedNamespaceListings (Names
                 ]
 
         hasOpenDefinitions =
-            openDefinitions
-                |> FQNSet.toList
-                |> List.any (\openFqn -> FQN.isSuffixOf name openFqn && not (FQN.equals openFqn name))
+            FQNSet.isPrefixOfAny openDefinitions name
     in
     div [ class "subtree" ]
         [ a

src/Code/FullyQualifiedName.elm

@@ -12,6 +12,7 @@ module Code.FullyQualifiedName exposing
     , fromString
     , fromUrlList
     , fromUrlString
+    , isPrefixOf
     , isRoot
     , isSuffixOf
     , isValidSegmentChar
@@ -293,6 +294,11 @@ isSuffixOf suffixName fqn =
     String.endsWith (toString suffixName) (toString fqn)
 
 
+isPrefixOf : FQN -> FQN -> Bool
+isPrefixOf prefixName fqn =
+    String.startsWith (toString prefixName) (toString fqn)
+
+
 isRoot : FQN -> Bool
 isRoot (FQN segments_) =
     case NEL.toList segments_ of

src/Code/FullyQualifiedNameSet.elm

@@ -5,6 +5,7 @@ module Code.FullyQualifiedNameSet exposing
     , fromReference
     , fromReferenceList
     , insert
+    , isPrefixOfAny
     , member
     , remove
     , singleton
@@ -85,6 +86,17 @@ toList (FQNSet set) =
         |> List.map FQN.fromString
 
 
+isPrefixOfAny : FQNSet -> FQN -> Bool
+isPrefixOfAny (FQNSet set) prefixFqn =
+    set
+        |> Set.toList
+        |> List.map FQN.fromString
+        |> List.any
+            (\item ->
+                FQN.isPrefixOf prefixFqn item && not (FQN.equals item prefixFqn)
+            )
+
+
 toggle : FQN -> FQNSet -> FQNSet
 toggle fqn (FQNSet set) =
     FQNSet (Set.Extra.toggle (FQN.toString fqn) set)

tests/Code/FullyQualifiedNameSetTests.elm

@@ -0,0 +1,27 @@
+module Code.FullyQualifiedNameSetTests exposing (..)
+
+import Code.FullyQualifiedName as FQN exposing (..)
+import Code.FullyQualifiedNameSet as FQNSet exposing (..)
+import Expect
+import List.Nonempty as NEL
+import Test exposing (..)
+
+
+isPrefixOfAny : Test
+isPrefixOfAny =
+    describe "FQNSet.isPrefixOfAny"
+        [ test "returns true when the given FQN is a prefix of any of the members of the set" <|
+            \_ ->
+                let
+                    prefix =
+                        FQN.fromList [ "BlogAuthor" ]
+
+                    set =
+                        FQNSet.fromList
+                            [ FQN.fromList [ "BlogAuthor", "avatar" ]
+                            , FQN.fromList [ "Blog", "view" ]
+                            , FQN.fromList [ "Css", "toText" ]
+                            ]
+                in
+                Expect.equal True (FQNSet.isPrefixOfAny set prefix)
+        ]

tests/Code/FullyQualifiedNameTests.elm

@@ -300,6 +300,36 @@ isSuffixOf =
         ]
 
 
+isPrefixOf : Test
+isPrefixOf =
+    describe "FullyQualifiedName.isPrefixOf"
+        [ test "Returns True when an FQN begin with the provided prefix" <|
+            \_ ->
+                let
+                    prefix =
+                        FQN.fromString "base.List"
+
+                    fqn =
+                        FQN.fromString "base.List.map"
+                in
+                FQN.isPrefixOf prefix fqn
+                    |> Expect.equal True
+                    |> Expect.onFail "is correctly a prefix of"
+        , test "Returns False when an FQN does begin with the provided prefix" <|
+            \_ ->
+                let
+                    prefix =
+                        FQN.fromString "base.Text"
+
+                    fqn =
+                        FQN.fromString "base.List.map"
+                in
+                FQN.isPrefixOf prefix fqn
+                    |> Expect.equal False
+                    |> Expect.onFail "is correctly *not* a prefix of"
+        ]
+
+
 namespaceOf : Test
 namespaceOf =
     describe "FullyQualifiedName.namespaceOf"