fix: tolerate search hits without snippet metadata

Treat DocSearch highlight and snippet payloads as optional crawler fields before reading nested content. This keeps the custom hit renderer from crashing when Algolia returns plain hits without _snippetResult.

Author: jderochervlk

__tests__/Search_.test.res

@@ -220,6 +220,36 @@ test("getContentHtml prefers crawler snippet markup over plain content", async (
   )
 })
 
+test(
+  "getContentHtml falls back to plain content when crawler hit has no snippet result",
+  async () => {
+    let hit: DocSearch.docSearchHit = Obj.magic(
+      Dict.fromArray([
+        ("objectID", "crawler-hit"),
+        ("content", "map(array, fn) returns a new array."),
+        ("url", "https://rescript-lang.org/docs/manual/api/stdlib/array/#value-map"),
+        ("type", "content"),
+        (
+          "hierarchy",
+          Obj.magic(
+            Dict.fromArray([
+              ("lvl0", Obj.magic("Array")),
+              ("lvl1", Obj.magic("map")),
+              ("lvl2", Obj.magic(Nullable.null)),
+              ("lvl3", Obj.magic(Nullable.null)),
+              ("lvl4", Obj.magic(Nullable.null)),
+              ("lvl5", Obj.magic(Nullable.null)),
+              ("lvl6", Obj.magic(Nullable.null)),
+            ]),
+          ),
+        ),
+      ]),
+    )
+
+    expect(Search.getContentHtml(hit))->toEqual(Some("map(array, fn) returns a new array."))
+  },
+)
+
 // ---------------------------------------------------------------------------
 // isChildHit
 // ---------------------------------------------------------------------------

src/bindings/DocSearch.res

@@ -50,8 +50,8 @@ type docSearchHit = {
   // Additional field for deprecation information
   deprecated: option<string>,
   // NOTE: docsearch need these two fields to highlight results
-  _highlightResult: highlightResult,
-  _snippetResult: snippetResult,
+  _highlightResult?: highlightResult,
+  _snippetResult?: snippetResult,
 }
 type transformItems = array<docSearchHit>
 

src/components/Search.res

@@ -112,7 +112,10 @@ let markTitlePrefix = (title: string, markedText: string): string => {
 }
 
 let getSnippetContent = (hit: DocSearch.docSearchHit): option<string> =>
-  hit._snippetResult.content->highlightedValue
+  switch hit._snippetResult {
+  | Some(snippetResult) => snippetResult.content->highlightedValue
+  | None => None
+  }
 
 let getApiTitle = (hit: DocSearch.docSearchHit): option<string> => {
   if hit.url->String.includes("/docs/manual/api/") {
@@ -131,7 +134,10 @@ let getApiTitle = (hit: DocSearch.docSearchHit): option<string> => {
 }
 
 let getHighlightedTitle = (hit: DocSearch.docSearchHit): string => {
-  let highlightedHierarchy = hit._highlightResult.hierarchy->Nullable.toOption
+  let highlightedHierarchy =
+    hit._highlightResult->Option.flatMap(highlightResult =>
+      highlightResult.hierarchy->Nullable.toOption
+    )
   let highlightedTitleWithMarkup = highlightedHierarchy->Option.flatMap(hierarchy =>
     switch hit.type_ {
     | Lvl0 | Lvl1 => None