Add @s.defaultWith

packages/rescript-schema-ppx/README.md

@@ -124,10 +124,10 @@ Specifies custom schema for the type.
 
 ```rescript
 @schema
-type url = @s.matches(S.string->S.String.url) string
+type t = @s.matches(S.string->S.String.url) string
 
 // Generated by PPX ⬇️
-let urlSchema = S.string->S.String.url
+let schema = S.string->S.String.url
 ```
 
 ### `@s.default('value)`
@@ -138,8 +138,22 @@ Wraps the type expression schema into an option with the provided default value.
 
 ```rescript
 @schema
-type stringWithDefault = @s.default("Unknown") string
+type t = @s.default("Unknown") string
 
 // Generated by PPX ⬇️
-let stringWithDefaultSchema = S.option(S.string)->S.Option.getOr("Unknown")
+let schema = S.option(S.string)->S.Option.getOr("Unknown")
+```
+
+### `@s.defaultWith(unit => 'value)`
+
+**Applies to**: type expressions
+
+Wraps the type expression schema into an option with callback to get the default value.
+
+```rescript
+@schema
+type t = @s.defaultWith(() => []) array<string>
+
+// Generated by PPX ⬇️
+let schema = S.option(S.array(S.string))->S.Option.getOrWith(() => [])
 ```

packages/rescript-schema-ppx/src/ppx/Structure.ml

@@ -173,6 +173,15 @@ and generateCoreTypeSchemaExpression {ptyp_desc; ptyp_loc; ptyp_attributes} =
         S.Option.getOr (S.option [%e schema_expression]) [%e default_value]]
     | Error s -> fail ptyp_loc s
   in
+  let schema_expression =
+    match getAttributeByName ptyp_attributes "s.defaultWith" with
+    | Ok None -> schema_expression
+    | Ok (Some attribute) ->
+      let default_cb = getExpressionFromPayload attribute in
+      [%expr
+        S.Option.getOrWith (S.option [%e schema_expression]) [%e default_cb]]
+    | Error s -> fail ptyp_loc s
+  in
   schema_expression
 
 let generateTypeDeclarationSchemaExpression type_declaration =

packages/tests/src/ppx/Ppx_Example_test.bs.mjs

@@ -38,22 +38,33 @@ Ava("Main example", (function (t) {
                 }), undefined);
       }));
 
-var urlSchema = S$RescriptSchema.$$String.url(S$RescriptSchema.string, undefined);
+var matchesSchema = S$RescriptSchema.$$String.url(S$RescriptSchema.string, undefined);
 
 Ava("@s.matches", (function (t) {
-        U.assertEqualSchemas(t, urlSchema, S$RescriptSchema.$$String.url(S$RescriptSchema.string, undefined), undefined);
+        U.assertEqualSchemas(t, matchesSchema, S$RescriptSchema.$$String.url(S$RescriptSchema.string, undefined), undefined);
       }));
 
-var stringWithDefaultSchema = S$RescriptSchema.$$Option.getOr(S$RescriptSchema.option(S$RescriptSchema.string), "Unknown");
+var defaultSchema = S$RescriptSchema.$$Option.getOr(S$RescriptSchema.option(S$RescriptSchema.string), "Unknown");
 
 Ava("@s.default", (function (t) {
-        U.assertEqualSchemas(t, stringWithDefaultSchema, S$RescriptSchema.$$Option.getOr(S$RescriptSchema.option(S$RescriptSchema.string), "Unknown"), undefined);
+        U.assertEqualSchemas(t, defaultSchema, S$RescriptSchema.$$Option.getOr(S$RescriptSchema.option(S$RescriptSchema.string), "Unknown"), undefined);
+      }));
+
+var defaultWithSchema = S$RescriptSchema.$$Option.getOrWith(S$RescriptSchema.option(S$RescriptSchema.array(S$RescriptSchema.string)), (function () {
+        return [];
+      }));
+
+Ava("@s.defaultWith", (function (t) {
+        U.assertEqualSchemas(t, defaultWithSchema, S$RescriptSchema.$$Option.getOrWith(S$RescriptSchema.option(S$RescriptSchema.array(S$RescriptSchema.string)), (function () {
+                    return [];
+                  })), undefined);
       }));
 
 export {
   ratingSchema ,
   filmSchema ,
-  urlSchema ,
-  stringWithDefaultSchema ,
+  matchesSchema ,
+  defaultSchema ,
+  defaultWithSchema ,
 }
 /* ratingSchema Not a pure module */

packages/tests/src/ppx/Ppx_Example_test.res

@@ -44,13 +44,22 @@ test("Main example", t => {
 })
 
 @schema
-type url = @s.matches(S.string->S.String.url) string
+type matches = @s.matches(S.string->S.String.url) string
 test("@s.matches", t => {
-  t->assertEqualSchemas(urlSchema, S.string->S.String.url)
+  t->assertEqualSchemas(matchesSchema, S.string->S.String.url)
 })
 
 @schema
-type stringWithDefault = @s.default("Unknown") string
+type default = @s.default("Unknown") string
 test("@s.default", t => {
-  t->assertEqualSchemas(stringWithDefaultSchema, S.option(S.string)->S.Option.getOr("Unknown"))
+  t->assertEqualSchemas(defaultSchema, S.option(S.string)->S.Option.getOr("Unknown"))
+})
+
+@schema
+type defaultWith = @s.defaultWith(() => []) array<string>
+test("@s.defaultWith", t => {
+  t->assertEqualSchemas(
+    defaultWithSchema,
+    S.option(S.array(S.string))->S.Option.getOrWith(() => []),
+  )
 })

packages/tests/src/utils/U.bs.mjs

@@ -43,23 +43,15 @@ function cleanUpSchema(schema) {
   Object.entries(schema).forEach(function (param) {
         var value = param[1];
         var key = param[0];
-        switch (key) {
-          case "f" :
-          case "i" :
-          case "n" :
-          case "op" :
-          case "opa" :
-          case "os" :
-          case "p" :
-          case "s" :
-              return ;
-          default:
-            if (typeof value === "object" && value !== null) {
-              $$new[key] = cleanUpSchema(value);
-            } else {
-              $$new[key] = value;
-            }
-            return ;
+        if (key === "i" || typeof value === "function") {
+          return ;
+        } else {
+          if (typeof value === "object" && value !== null) {
+            $$new[key] = cleanUpSchema(value);
+          } else {
+            $$new[key] = value;
+          }
+          return ;
         }
       });
   return $$new;

packages/tests/src/utils/U.res

@@ -36,9 +36,11 @@ let rec cleanUpSchema = schema => {
   ->Dict.toArray
   ->Array.forEach(((key, value)) => {
     switch key {
-    | "s" | "p" | "i" | "f" | "n" | "os" | "op" | "opa" => ()
+    | "i" => ()
     | _ =>
-      if typeof(value) === #object && value !== %raw(`null`) {
+      if typeof(value) === #function {
+        ()
+      } else if typeof(value) === #object && value !== %raw(`null`) {
         new->Dict.set(
           key,
           cleanUpSchema(value->(magic: unknown => S.t<'a>))->(magic: S.t<'a> => unknown),