Extend nodeOuterHtml to all node types

digitallyinduced · Nov 4, 2021 · 5994969 · 5994969
1 parent 951141e
commit 5994969
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Showing 3 changed files with 21 additions and 2 deletions.
diff --git a/IHP/ServerSideComponent/HtmlDiff.hs b/IHP/ServerSideComponent/HtmlDiff.hs
@@ -73,7 +73,7 @@ diffNodes' path Children { children = oldChildren } Children { children = newChi
             patchElements (new:nextNewNode:newRest) (old:oldRest) !index | (not $ new `isNodeEqIgnoringPosition` old) && (old `isNodeEqIgnoringPosition` nextNewNode) = [ CreateNode { html = nodeOuterHtml new ?newHtml, path = (index:path) } ] <> (patchElements (newRest) (oldRest) (index + 2)) -- [A, C <old>] -> [A, B <new>, C <nextNewNode>]
             patchElements (new:newRest) (old:nextOld:oldRest) !index | (not $ new `isNodeEqIgnoringPosition` old) && (new `isNodeEqIgnoringPosition` nextOld) = [ DeleteNode { node = old, path = (index:path) } ] <> (patchElements (newRest) (oldRest) (index + 1)) -- [A, B <old>, C <nextOldNode> ] -> [A, C <new>]
             patchElements (new:newRest) (old:oldRest) !index = (diffNodes' (index:path) old new) <> (patchElements newRest oldRest (index + 1))
-            patchElements (new:newRest) oldRest !index = [ CreateNode { html = nodeOuterHtml new ?newHtml, path = (index:path) } ] <> (patchElements newRest oldRest (index + 1))
+            patchElements (new:newRest) [] !index = [ CreateNode { html = nodeOuterHtml new ?newHtml, path = (index:path) } ] <> (patchElements newRest [] (index + 1))
             patchElements [] (old:oldRest) !index = [ DeleteNode { node = old, path = (index:path) } ] <> (patchElements [] oldRest (index + 1))
             patchElements [] [] _ = []
         in
@@ -108,10 +108,19 @@ diffAttributes old new = addOrUpdateAttributes <> deleteAttributes
         matchAttribute :: [Attribute] -> Attribute -> Maybe Attribute
         matchAttribute attributes Attribute { attributeName } = find (\Attribute { attributeName = attributeName' } -> attributeName == attributeName' ) attributes
 
+-- | Grabs the entire HTML string corresponding to the node boundaries.
+--
+-- Node boundaries are only stored for 'Node'. Other nodes ('TextNode', etc) don't store start/end offset, so we render
+-- them by ourselves.
 nodeOuterHtml :: Node -> Text -> Text
 nodeOuterHtml Node { startOffset, endOffset } html = html
         |> Text.drop startOffset
         |> Text.take (endOffset - startOffset)
+-- Assuming chars are already escaped, because that's what HSX produces
+nodeOuterHtml TextNode { textContent } _ = textContent
+nodeOuterHtml PreEscapedTextNode { textContent } _ = textContent
+nodeOuterHtml Children { children } html = mconcat $ map (`nodeOuterHtml` html) children
+nodeOuterHtml CommentNode { comment } _ = "<!--" <> comment <> "-->"
 
 isNodeEqIgnoringPosition :: Node -> Node -> Bool
 isNodeEqIgnoringPosition a@(Node {}) b@(Node {}) = (a { startOffset = 0, endOffset = 0 }) == (b { startOffset = 0, endOffset = 0 })

diff --git a/IHP/ServerSideComponent/HtmlParser.hs b/IHP/ServerSideComponent/HtmlParser.hs
@@ -22,7 +22,7 @@ data Attribute = Attribute
     } deriving (Eq, Show)
 
 data Node = Node { tagName :: !Text, attributes :: ![Attribute], children :: ![Node], startOffset :: Int, endOffset :: Int }
-    | TextNode { textContent :: !Text }
+    | TextNode { textContent :: !Text } -- ^ Note: doesn't unescape chars like &lt;
     | PreEscapedTextNode { textContent :: !Text } -- ^ Used in @script@ or @style@ bodies
     | Children { children :: ![Node] }
     | CommentNode { comment :: !Text }

diff --git a/Test/ServerSideComponent/HtmlDiffSpec.hs b/Test/ServerSideComponent/HtmlDiffSpec.hs
@@ -55,6 +55,16 @@ tests = do
                     let expected = [UpdatePreEscapedTextNode { textContent = "alert(2)", path = [] }]
                     result `shouldBe` expected
 
+                it "should insert text and comment nodes (#1192)" do
+                    let a = Node {tagName = "span", attributes = [], children = [], startOffset = 0, endOffset = 0}
+                    let b = Node {tagName = "span", attributes = [], children = [TextNode {textContent = "string"}, CommentNode {comment = "test"}], startOffset = 0, endOffset = 0}
+                    let result = diffNodes a b
+                    let expected = 
+                            [ CreateNode {html = "string", path = [0]}
+                            , CreateNode {html = "<!--test-->", path = [1]}
+                            ]
+                    result `shouldBe` expected
+
                 it "should replace nodes if the tag name is different" do
                     let a = Node { tagName = "a", attributes = [Attribute { attributeName = "href", attributeValue = "#" }], children = [ TextNode { textContent = "hello" } ], startOffset = 0, endOffset = 0 }
                     let b = Node { tagName = "div", attributes = [Attribute { attributeName = "class", attributeValue = "d-block" }], children = [], startOffset = 0, endOffset = 0 }