Make Cid.to_string only return string or fail

ipld/lib/cid.ml

···
 let to_string cid =
   match Multibase.encode `Base32 (Bytes.to_string cid.bytes) with
   | Ok str ->
-      Ok str
+      str
   | Error (`Msg msg) ->
-      Error msg
+      failwith msg
   | Error (`Unsupported t) ->
-      Error
+      failwith
         (Printf.sprintf "Unsupported multibase %s"
            (Multibase.Encoding.to_string t) )
 
···
   Buffer.add_bytes buf cid.bytes ;
   Buffer.to_bytes buf
 
-let compare a b =
-  match [to_string a; to_string b] with
-  | [Ok a; Ok b] ->
-      String.compare a b
-  | _ ->
-      failwith "CID comparison failed"
+let as_cid str = Result.get_ok @@ of_string str
 
-let equal a b =
-  match [to_string a; to_string b] with
-  | [Ok a; Ok b] ->
-      String.equal a b
-  | _ ->
-      failwith "CID comparison failed"
+let compare a b = String.compare (to_string a) (to_string b)
+
+let equal a b = String.equal (to_string a) (to_string b)
 
 let hash = Hashtbl.hash

ipld/test/test_cid.ml

···
   Alcotest.(check bytes) "bytes" (bytes_from_list [1; 113; 18; 0]) cid.bytes
 
 let test_create () =
-  let cid = Cid.(create Dcbor (Bytes.of_string "abc")) in
-  let str = Result.get_ok (Cid.to_string cid) in
+  let cid = Cid.(create Dcbor (Bytes.of_string "abc") |> to_string) in
   Alcotest.(check string)
-    "digest" "bafyreif2pall7dybz7vecqka3zo24irdwabwdi4wc55jznaq75q7eaavvu" str
+    "digest" "bafyreif2pall7dybz7vecqka3zo24irdwabwdi4wc55jznaq75q7eaavvu" cid
 
 let test_create_empty_string () =
   let cid = Cid.(create_empty Dcbor) in

ipld/test/test_dag_cbor.ml

···
   | `Link cid ->
       Format.sprintf "%s"
         (stringify_map
-           (StringMap.singleton "$link"
-              (`String (Result.get_ok (Cid.to_string cid))) ) )
+           (StringMap.singleton "$link" (`String (Cid.to_string cid))) )
   | `Null ->
       Format.sprintf "null"
 
···
   | `Array a, `Array b ->
       Array.for_all2 ipld_value_eq a b
   | `Link a, `Link b ->
-      Result.get_ok @@ Cid.to_string a = Result.get_ok @@ Cid.to_string b
+      Cid.to_string a = Cid.to_string b
   | `Null, `Null ->
       true
   | _ ->
···
       |> add "$type" (`String "blob")
       |> add "ref"
            (`Link
-             (Result.get_ok
-                (Cid.of_string
-                   "bafkreic6hvmy3ymbo25wxsvylu77r57uwhtnviu7vmhfsns3ab4xfal5ou" ) )
-             )
+              (Result.get_ok
+                 (Cid.of_string
+                    "bafkreic6hvmy3ymbo25wxsvylu77r57uwhtnviu7vmhfsns3ab4xfal5ou" ) )
+           )
       |> add "mimeType" (`String "image/jpeg")
       |> add "size" (`Integer 645553L) )
   in
···
       empty
       |> add "alt"
            (`String
-             "a photoshopped picture of kit with a microphone. kit is saying \
-              \"meow\"" )
+              "a photoshopped picture of kit with a microphone. kit is saying \
+               \"meow\"" )
       |> add "aspectRatio" (`Map record1_embed_images_0_aspect_ratio)
       |> add "image" (`Map record1_embed_images_0_image) )
   in
···
   Alcotest.(check string)
     "atproto record 1 encodes correctly"
     "bafyreicbb3p4hmtm7iw3k7kiydzqp7qhufq3jdc5sbc4gxa4mxqd6bywba"
-    Cid.(create Dcbor encoded1 |> to_string |> Result.get_ok) ;
+    Cid.(create Dcbor encoded1 |> to_string) ;
   let record2_embed_images_0_aspect_ratio : Dag_cbor.value StringMap.t =
     StringMap.(
       empty |> add "height" (`Integer 2000L) |> add "width" (`Integer 1500L) )
···
       |> add "$type" (`String "blob")
       |> add "ref"
            (`Link
-             ( Result.get_ok
-             @@ Cid.of_string
-                  "bafkreibdqy5qcefkcuvopnkt2tip5wzouscmp6duz377cneknktnsgfewe"
-             ) )
+              ( Result.get_ok
+              @@ Cid.of_string
+                   "bafkreibdqy5qcefkcuvopnkt2tip5wzouscmp6duz377cneknktnsgfewe"
+              ) )
       |> add "mimeType" (`String "image/jpeg")
       |> add "size" (`Integer 531257L) )
   in
···
       empty
       |> add "features"
            (`Array
-             [| `Map
-                  ( StringMap.empty
-                  |> StringMap.add "$type"
-                       (`String "app.bsky.richtext.facet#tag")
-                  |> StringMap.add "tag" (`String "写真") ) |] )
+              [| `Map
+                   ( StringMap.empty
+                   |> StringMap.add "$type"
+                        (`String "app.bsky.richtext.facet#tag")
+                   |> StringMap.add "tag" (`String "写真") ) |] )
       |> add "index"
            (`Map
-             ( StringMap.empty
-             |> StringMap.add "byteEnd" (`Integer 109L)
-             |> StringMap.add "byteStart" (`Integer 100L) ) ) )
+              ( StringMap.empty
+              |> StringMap.add "byteEnd" (`Integer 109L)
+              |> StringMap.add "byteStart" (`Integer 100L) ) ) )
   in
   let record2_facets_1 : Dag_cbor.value StringMap.t =
     StringMap.(
       empty
       |> add "features"
            (`Array
-             [| `Map
-                  ( StringMap.empty
-                  |> StringMap.add "$type"
-                       (`String "app.bsky.richtext.facet#tag")
-                  |> StringMap.add "tag" (`String "日の出") ) |] )
+              [| `Map
+                   ( StringMap.empty
+                   |> StringMap.add "$type"
+                        (`String "app.bsky.richtext.facet#tag")
+                   |> StringMap.add "tag" (`String "日の出") ) |] )
       |> add "index"
            (`Map
-             ( StringMap.empty
-             |> StringMap.add "byteEnd" (`Integer 122L)
-             |> StringMap.add "byteStart" (`Integer 110L) ) ) )
+              ( StringMap.empty
+              |> StringMap.add "byteEnd" (`Integer 122L)
+              |> StringMap.add "byteStart" (`Integer 110L) ) ) )
   in
   let record2_facets_2 : Dag_cbor.value StringMap.t =
     StringMap.(
       empty
       |> add "features"
            (`Array
-             [| `Map
-                  ( StringMap.empty
-                  |> StringMap.add "$type"
-                       (`String "app.bsky.richtext.facet#tag")
-                  |> StringMap.add "tag" (`String "日常") ) |] )
+              [| `Map
+                   ( StringMap.empty
+                   |> StringMap.add "$type"
+                        (`String "app.bsky.richtext.facet#tag")
+                   |> StringMap.add "tag" (`String "日常") ) |] )
       |> add "index"
            (`Map
-             ( StringMap.empty
-             |> StringMap.add "byteEnd" (`Integer 132L)
-             |> StringMap.add "byteStart" (`Integer 123L) ) ) )
+              ( StringMap.empty
+              |> StringMap.add "byteEnd" (`Integer 132L)
+              |> StringMap.add "byteStart" (`Integer 123L) ) ) )
   in
   let record2_facets_3 : Dag_cbor.value StringMap.t =
     StringMap.(
       empty
       |> add "features"
            (`Array
-             [| `Map
-                  ( StringMap.empty
-                  |> StringMap.add "$type"
-                       (`String "app.bsky.richtext.facet#tag")
-                  |> StringMap.add "tag" (`String "キリトリセカイ") ) |] )
+              [| `Map
+                   ( StringMap.empty
+                   |> StringMap.add "$type"
+                        (`String "app.bsky.richtext.facet#tag")
+                   |> StringMap.add "tag" (`String "キリトリセカイ") ) |] )
       |> add "index"
            (`Map
-             ( StringMap.empty
-             |> StringMap.add "byteEnd" (`Integer 157L)
-             |> StringMap.add "byteStart" (`Integer 133L) ) ) )
+              ( StringMap.empty
+              |> StringMap.add "byteEnd" (`Integer 157L)
+              |> StringMap.add "byteStart" (`Integer 133L) ) ) )
   in
   let record2_facets =
     [| `Map record2_facets_0
···
       |> add "langs" (`Array [|`String "ja"|])
       |> add "text"
            (`String
-             "おはようございます☀️\n今日の日の出です\n寒かったけど綺麗でしたよ✨\n\n＃写真\n＃日の出\n＃日常\n＃キリトリセカイ"
-             )
+              "おはようございます☀️\n今日の日の出です\n寒かったけど綺麗でしたよ✨\n\n＃写真\n＃日の出\n＃日常\n＃キリトリセカイ"
+           )
       |> add "embed" (`Map record2_embed)
       |> add "facets" (`Array record2_facets) )
   in
···
   Alcotest.(check string)
     "atproto record 2 encodes correctly"
     "bafyreiarjuvb3oppjnouaiasitt2tekkhhge6qsd4xegutblzgmihmnrhi"
-    Cid.(create Dcbor encoded2 |> to_string |> Result.get_ok)
+    Cid.(create Dcbor encoded2 |> to_string)
 
 let test_invalid_numbers () =
   Alcotest.check_raises "encode rejects out of range positive integer"