Disallow use of union types in args and return types

daniel-chambers · daniel-chambers · commit 002860d124da · 2024-01-17T15:53:39.000+11:00
diff --git a/ndc-lambda-sdk/src/inference.ts b/ndc-lambda-sdk/src/inference.ts
@@ -306,6 +306,10 @@ function deriveSchemaTypeForTsType(tsType: ts.Type, typePath: TypePathSegment[],
     return new Err([`Class types are not supported, but one was encountered in ${typePathToString(typePath)} (type: ${context.typeChecker.typeToString(tsType)})`]);
   }
 
+  if (tsType.isUnion()) {
+    return new Err([`Union types are not supported, but one was encountered in ${typePathToString(typePath)} (type: ${context.typeChecker.typeToString(tsType)})`]);
+  }
+
   // We don't know how to deal with this type, so just make it an opaque scalar
   const typeName = generateTypeNameFromTypePath(typePath);
   context.scalarTypeDefinitions[typeName] = {};
diff --git a/ndc-lambda-sdk/test/inference/basic-inference/basic-inference.test.ts b/ndc-lambda-sdk/test/inference/basic-inference/basic-inference.test.ts
@@ -499,11 +499,7 @@ describe("basic inference", function() {
 
     assert.deepStrictEqual(schema, {
       compilerDiagnostics: [],
-      functionIssues: {
-        "test": [
-          "Unable to derive an NDC type for function 'test' parameter 'unionWithNull' (type: string | number | null). Assuming that it is a scalar type."
-        ]
-      },
+      functionIssues: {},
       functionsSchema: {
         functions: {
           "test": {
@@ -556,15 +552,6 @@ describe("basic inference", function() {
                   },
                 },
               },
-              {
-                argumentName: "unionWithNull",
-                description: null,
-                type: {
-                  kind: "scalar",
-                  name: "test_arguments_unionWithNull",
-                  type: "named",
-                },
-              },
               {
                 argumentName: "optionalParam",
                 description: null,
@@ -656,7 +643,6 @@ describe("basic inference", function() {
         },
         scalarTypes: {
           String: {},
-          test_arguments_unionWithNull: {},
         },
       }
     })
diff --git a/ndc-lambda-sdk/test/inference/basic-inference/nullable-types.ts b/ndc-lambda-sdk/test/inference/basic-inference/nullable-types.ts
@@ -11,7 +11,6 @@ export function test(
   nullableParam: string | null,
   undefinedParam: string | undefined,
   nullOrUndefinedParam: string | undefined | null,
-  unionWithNull: string | number | null,
   optionalParam?: string
 ): string | null {
   return "test"
diff --git a/ndc-lambda-sdk/test/inference/external-dependencies/external-dependencies.test.ts b/ndc-lambda-sdk/test/inference/external-dependencies/external-dependencies.test.ts
@@ -46,17 +46,7 @@ describe("external dependencies", function() {
 
     assert.deepStrictEqual(schema, {
       compilerDiagnostics: [],
-      functionIssues: {
-        "delete_todos": [
-          "Unable to derive an NDC type for function 'delete_todos' return value (type: string | { error: string; }). Assuming that it is a scalar type."
-        ],
-        "insert_todos": [
-          "Unable to derive an NDC type for function 'insert_todos' return value (type: {} | { id: string; user_id: string; todo: string; created_at: string; } | { message: string; } | { error: string; }). Assuming that it is a scalar type."
-        ],
-        "insert_user": [
-          "Unable to derive an NDC type for function 'insert_user' return value (type: {} | { id: string; name: string; created_at: string; } | { message: string; } | { error: string; }). Assuming that it is a scalar type."
-        ],
-      },
+      functionIssues: {},
       functionsSchema: {
         functions: {
           "insert_user": {
@@ -76,7 +66,7 @@ describe("external dependencies", function() {
             resultType: {
               type: "named",
               kind: "scalar",
-              name: "insert_user_output"
+              name: "JSON"
             }
           },
           "insert_todos": {
@@ -105,7 +95,7 @@ describe("external dependencies", function() {
             resultType: {
               type: "named",
               kind: "scalar",
-              name: "insert_todos_output"
+              name: "JSON"
             }
           },
           "delete_todos": {
@@ -124,18 +114,45 @@ describe("external dependencies", function() {
             ],
             resultType: {
               type: "named",
-              kind: "scalar",
+              kind: "object",
               name: "delete_todos_output"
             }
           },
         },
         scalarTypes: {
           String: {},
-          insert_todos_output: {},
-          insert_user_output: {},
-          delete_todos_output: {},
+          JSON: {}
+        },
+        objectTypes: {
+          "delete_todos_output": {
+            properties: [
+              {
+                propertyName: "error",
+                type: {
+                  nullOrUndefinability: NullOrUndefinability.AcceptsUndefinedOnly,
+                  type: "nullable",
+                  underlyingType: {
+                    kind: "scalar",
+                    name: "String",
+                    type: "named",
+                  }
+                }
+              },
+              {
+                propertyName: "result",
+                type: {
+                  nullOrUndefinability: NullOrUndefinability.AcceptsUndefinedOnly,
+                  type: "nullable",
+                  underlyingType: {
+                    kind: "scalar",
+                    name: "String",
+                    type: "named",
+                  }
+                }
+              }
+            ]
+          }
         },
-        objectTypes: {},
       }
     })
   });
diff --git a/ndc-lambda-sdk/test/inference/external-dependencies/use-postgres-package.ts b/ndc-lambda-sdk/test/inference/external-dependencies/use-postgres-package.ts
@@ -1,4 +1,5 @@
 import { Client } from "node-postgres";
+import * as sdk from "../../../src/schema";
 
 const dbConfig = {
   user: "aaysha",
@@ -12,11 +13,7 @@ const dbConfig = {
 
 export async function insert_user(
   user_name: string,
-): Promise<
-  { id: string; name: string; created_at: string } | { message: string } | {
-    error: string;
-  } | {}
-> {
+): Promise<sdk.JSONValue> {
   const client = new Client(dbConfig);
 
   try {
@@ -29,14 +26,14 @@ export async function insert_user(
     if (result && result.rows.length > 0 && result.rows[0]) {
       return result.rows[0];
     } else {
-      return { message: "Insert Failed" };
+      return new sdk.JSONValue({ message: "Insert Failed" });
     }
   } catch (error) {
     console.error("Error:", error);
     if (error != null && typeof error === "object" && "message" in error) {
-      return { error: "Error: " + error.message };
+      return new sdk.JSONValue({ error: "Error: " + error.message });
     } else {
-      return { error: "Unknown error" };
+      return new sdk.JSONValue({ error: "Unknown error" });
     }
   } finally {
     await client.end();
@@ -46,11 +43,7 @@ export async function insert_user(
 export async function insert_todos(
     user_id: string,
     todo: string
-  ): Promise<
-    { id: string; user_id: string; todo: string; created_at: string } | { message: string } | {
-      error: string;
-    } | {}
-  > {
+  ): Promise<sdk.JSONValue> {
     const client = new Client(dbConfig);
 
     try {
@@ -62,7 +55,7 @@ export async function insert_todos(
       })
 
       if (userExistsQuery.rows.length === 0) {
-        return { message: "User not found. Insert Failed" };
+        return new sdk.JSONValue({ message: "User not found. Insert Failed" });
       }
       const result = await client.query({
         text: `INSERT INTO todos(user_id,todo) VALUES ('${user_id}','${todo}') RETURNING *`,
@@ -71,14 +64,14 @@ export async function insert_todos(
       if (result && result.rows.length > 0 && result.rows[0]) {
         return result.rows[0];
       } else {
-        return { message: "Insert Failed" };
+        return new sdk.JSONValue({ message: "Insert Failed" });
       }
     } catch (error) {
       console.error("Error:", error);
       if (error != null && typeof error === "object" && "message" in error) {
-        return { error: "Error: " + error.message };
+        return new sdk.JSONValue({ error: "Error: " + error.message });
       } else {
-        return { error: "Unknown error" };
+        return new sdk.JSONValue({ error: "Unknown error" });
       }
     } finally {
       await client.end();
@@ -88,16 +81,16 @@ export async function insert_todos(
 
   export async function delete_todos(
     todo_id: string
-  ){
+  ): Promise<{ error?: string, result?: string }> {
     const client = new Client(dbConfig);
     try {
       await client.connect();
 
       const result = await client.query({ text: `DELETE FROM todos WHERE id =${todo_id}`})
       if (result.rowCount === 1) {
-        return `Deleted todo with id= ${todo_id} successfully`
+        return { result: `Deleted todo with id= ${todo_id} successfully` }
       } else {
-        return "Deletion unsuccessful"
+        return { result: "Deletion unsuccessful" }
       }
     } catch (error) {
       if (error != null && typeof error === "object" && "message" in error) {
diff --git a/ndc-lambda-sdk/test/inference/unsupported-types/union-types.ts b/ndc-lambda-sdk/test/inference/unsupported-types/union-types.ts
@@ -0,0 +1,9 @@
+type AliasedUnion = string | boolean;
+
+export function unionTypes(
+  numberOrString: number | string,
+  aliasedUnion: AliasedUnion,
+  unionedObjects: { prop1: string } | { prop2: string }
+): string {
+  return ""
+}
diff --git a/ndc-lambda-sdk/test/inference/unsupported-types/unsupported-types.test.ts b/ndc-lambda-sdk/test/inference/unsupported-types/unsupported-types.test.ts
@@ -217,4 +217,26 @@ describe("unsupported types", function() {
       }
     })
   });
+
+  it("union types", function() {
+    const schema = deriveSchema(require.resolve("./union-types.ts"));
+
+    assert.deepStrictEqual(schema, {
+      compilerDiagnostics: [],
+      functionIssues: {
+        "unionTypes": [
+          "Union types are not supported, but one was encountered in function 'unionTypes' parameter 'numberOrString' (type: string | number)",
+          "Union types are not supported, but one was encountered in function 'unionTypes' parameter 'aliasedUnion' (type: AliasedUnion)",
+          "Union types are not supported, but one was encountered in function 'unionTypes' parameter 'unionedObjects' (type: { prop1: string; } | { prop2: string; })"
+        ],
+      },
+      functionsSchema: {
+        scalarTypes: {
+          String: {}
+        },
+        objectTypes: {},
+        functions: {}
+      }
+    })
+  });
 });
