add union type test to baselines

Author: danvk

tests/baselines/reference/inferTypePredicates.errors.txt

@@ -275,4 +275,13 @@ inferTypePredicates.ts(205,7): error TS2741: Property 'z' is missing in type 'C1
     } else {
       let t: never = str;  // should OK
     }
+    
+    // infer a union type
+    function isNumOrStr(x: unknown) {
+      return (typeof x === "number" || typeof x === "string");
+    }
+    declare let unk: unknown;
+    if (isNumOrStr(unk)) {
+      let t: number | string = unk;  // should ok
+    }
 

tests/baselines/reference/inferTypePredicates.js

@@ -232,6 +232,15 @@ if (isStringFromUnknown(str)) {
 } else {
   let t: never = str;  // should OK
 }
+
+// infer a union type
+function isNumOrStr(x: unknown) {
+  return (typeof x === "number" || typeof x === "string");
+}
+declare let unk: unknown;
+if (isNumOrStr(unk)) {
+  let t: number | string = unk;  // should ok
+}
 
 
 //// [inferTypePredicates.js]
@@ -443,3 +452,10 @@ if (isStringFromUnknown(str)) {
 else {
     var t = str; // should OK
 }
+// infer a union type
+function isNumOrStr(x) {
+    return (typeof x === "number" || typeof x === "string");
+}
+if (isNumOrStr(unk)) {
+    var t = unk; // should ok
+}

tests/baselines/reference/inferTypePredicates.symbols

@@ -659,3 +659,24 @@ if (isStringFromUnknown(str)) {
 >str : Symbol(str, Decl(inferTypePredicates.ts, 216, 11))
 }
 
+// infer a union type
+function isNumOrStr(x: unknown) {
+>isNumOrStr : Symbol(isNumOrStr, Decl(inferTypePredicates.ts, 230, 1))
+>x : Symbol(x, Decl(inferTypePredicates.ts, 233, 20))
+
+  return (typeof x === "number" || typeof x === "string");
+>x : Symbol(x, Decl(inferTypePredicates.ts, 233, 20))
+>x : Symbol(x, Decl(inferTypePredicates.ts, 233, 20))
+}
+declare let unk: unknown;
+>unk : Symbol(unk, Decl(inferTypePredicates.ts, 236, 11))
+
+if (isNumOrStr(unk)) {
+>isNumOrStr : Symbol(isNumOrStr, Decl(inferTypePredicates.ts, 230, 1))
+>unk : Symbol(unk, Decl(inferTypePredicates.ts, 236, 11))
+
+  let t: number | string = unk;  // should ok
+>t : Symbol(t, Decl(inferTypePredicates.ts, 238, 5))
+>unk : Symbol(unk, Decl(inferTypePredicates.ts, 236, 11))
+}
+

tests/baselines/reference/inferTypePredicates.types

@@ -854,3 +854,33 @@ if (isStringFromUnknown(str)) {
 >str : never
 }
 
+// infer a union type
+function isNumOrStr(x: unknown) {
+>isNumOrStr : (x: unknown) => x is string | number
+>x : unknown
+
+  return (typeof x === "number" || typeof x === "string");
+>(typeof x === "number" || typeof x === "string") : boolean
+>typeof x === "number" || typeof x === "string" : boolean
+>typeof x === "number" : boolean
+>typeof x : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>x : unknown
+>"number" : "number"
+>typeof x === "string" : boolean
+>typeof x : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>x : unknown
+>"string" : "string"
+}
+declare let unk: unknown;
+>unk : unknown
+
+if (isNumOrStr(unk)) {
+>isNumOrStr(unk) : boolean
+>isNumOrStr : (x: unknown) => x is string | number
+>unk : unknown
+
+  let t: number | string = unk;  // should ok
+>t : string | number
+>unk : string | number
+}
+