BREAKING(yargs): fix InferredOptionType inference (DefinitelyTyped#52624

) * fix(yargs): fix type inference of InferredOptionType * test(yargs): add test using default and demandOption together
pragdave · May 18, 2021 · 293f8fa · 293f8fa
1 parent 3107a07
commit 293f8fa
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Showing 2 changed files with 22 additions and 4 deletions.
diff --git a/types/yargs/index.d.ts b/types/yargs/index.d.ts
@@ -781,14 +781,20 @@ declare namespace yargs {
     type ToNumber<T> = (Exclude<T, undefined> extends any[] ? number[] : number) | Extract<T, undefined>;
 
     type InferredOptionType<O extends Options | PositionalOptions> =
+        O extends (
+            | { required: string | true }
+            | { require: string | true }
+            | { demand: string | true }
+            | { demandOption: string | true }
+        ) ?
+        Exclude<InferredOptionTypeInner<O>, undefined> :
+        InferredOptionTypeInner<O>;
+
+    type InferredOptionTypeInner<O extends Options | PositionalOptions> =
         O extends { default: any, coerce: (arg: any) => infer T } ? T :
         O extends { default: infer D } ? D :
         O extends { type: "count" } ? number :
         O extends { count: true } ? number :
-        O extends { required: string | true } ? RequiredOptionType<O> :
-        O extends { require: string | true } ? RequiredOptionType<O> :
-        O extends { demand: string | true } ? RequiredOptionType<O> :
-        O extends { demandOption: string | true } ? RequiredOptionType<O> :
         RequiredOptionType<O> | undefined;
 
     type RequiredOptionType<O extends Options | PositionalOptions> =

diff --git a/types/yargs/yargs-tests.ts b/types/yargs/yargs-tests.ts
@@ -1050,6 +1050,18 @@ function Argv$inferRequiredOptionTypes() {
 
     // $ExpectType (string | number)[]
     yargs.option("x", { array: true, demandOption: true }).argv.x;
+
+    // $ExpectType string
+    yargs.option("x", { default: "default" as string | undefined, demandOption: true }).argv.x;
+
+    // $ExpectType string
+    yargs.option("x", { default: "default" as string | undefined, demand: true }).argv.x;
+
+    // $ExpectType string
+    yargs.option("x", { default: "default" as string | undefined, require: true }).argv.x;
+
+    // $ExpectType string
+    yargs.option("x", { default: "default" as string | undefined, required: true }).argv.x;
 }
 
 function Argv$inferMultipleOptionTypes() {