Restrict type of BigInt argument

PiperOrigin-RevId: 324305274

Author: JohnLuck77

src/com/google/javascript/jscomp/testing/TestExternsBuilder.java

@@ -61,7 +61,7 @@ private static final String lines(String... lines) {
       lines(
           "/** ",
           " * @constructor",
-          " * @param {*} arg",
+          " * @param {bigint|number|string} arg",
           " * @return {bigint}",
           " */",
           "function BigInt(arg) {}",

src/com/google/javascript/rhino/jstype/JSTypeRegistry.java

@@ -615,10 +615,14 @@ private void initializeBuiltInTypes() {
     registerNativeType(JSTypeNative.PROMISE_FUNCTION_TYPE, promiseFunctionType);
     registerNativeType(JSTypeNative.PROMISE_TYPE, promiseFunctionType.getInstanceType());
 
+    // (bigint,number,string)
+    JSType bigintNumberString = createUnionType(bigIntType, numberType, stringType);
+    registerNativeType(BIGINT_NUMBER_STRING, bigintNumberString);
+
     // BigInt
     FunctionType bigIntObjectFunctionType =
         nativeConstructorBuilder("BigInt")
-            .withParameters(createParameters(allType))
+            .withParameters(createParameters(bigintNumberString))
             .withReturnType(bigIntType)
             .build();
     bigIntObjectFunctionType.getPrototype(); // Force initialization
@@ -742,10 +746,6 @@ private void initializeBuiltInTypes() {
     JSType bigintNumberObject = createUnionType(bigIntObjectType, numberObjectType);
     registerNativeType(BIGINT_NUMBER_OBJECT, bigintNumberObject);
 
-    // (bigint,number,string)
-    JSType bigintNumberString = createUnionType(bigIntType, numberType, stringType);
-    registerNativeType(BIGINT_NUMBER_STRING, bigintNumberString);
-
     // (Bigint,Number,String)
     JSType bigintNumberStringObject =
         createUnionType(bigIntObjectType, numberObjectType, stringObjectType);

test/com/google/javascript/jscomp/TypeCheckTest.java

@@ -23728,6 +23728,17 @@ public void testStrictNumericOperators10() {
             "required: number"));
   }
 
+  @Test
+  public void testBigIntArgument() {
+    testTypes("BigInt(1)");
+    testTypes(
+        "BigInt({})",
+        lines(
+            "actual parameter 1 of BigInt does not match formal parameter",
+            "found   : {}",
+            "required: (bigint|number|string)"));
+  }
+
   @Test
   public void testBigIntOperators_increment() {
     testTypes("const x = 1n; x++;");