LibJS: Implement ECMA-402 BigInt.prototype.toLocaleString

2 files changed, 95 insertions, 1 deletions

diff --git a/Userland/Libraries/LibJS/Runtime/BigIntPrototype.cpp b/Userland/Libraries/LibJS/Runtime/BigIntPrototype.cpp
index d2e2092111..ff1ef54b53 100644
--- a/Userland/Libraries/LibJS/Runtime/BigIntPrototype.cpp
+++ b/Userland/Libraries/LibJS/Runtime/BigIntPrototype.cpp
@@ -6,11 +6,14 @@
 
 #include <AK/Function.h>
 #include <AK/TypeCasts.h>
+#include <LibJS/Runtime/AbstractOperations.h>
 #include <LibJS/Runtime/BigIntObject.h>
 #include <LibJS/Runtime/BigIntPrototype.h>
 #include <LibJS/Runtime/Completion.h>
 #include <LibJS/Runtime/Error.h>
 #include <LibJS/Runtime/GlobalObject.h>
+#include <LibJS/Runtime/Intl/NumberFormat.h>
+#include <LibJS/Runtime/Intl/NumberFormatConstructor.h>
 
 namespace JS {
 
@@ -61,9 +64,21 @@ JS_DEFINE_NATIVE_FUNCTION(BigIntPrototype::to_string)
 }
 
 // 21.2.3.2 BigInt.prototype.toLocaleString ( [ reserved1 [ , reserved2 ] ] ), https://tc39.es/ecma262/#sec-bigint.prototype.tolocalestring
+// 19.3.1 BigInt.prototype.toLocaleString ( [ locales [ , options ] ] ), https://tc39.es/ecma402/#sup-bigint.prototype.tolocalestring
 JS_DEFINE_NATIVE_FUNCTION(BigIntPrototype::to_locale_string)
 {
-    return to_string(vm, global_object);
+    auto locales = vm.argument(0);
+    auto options = vm.argument(1);
+
+    // 1. Let x be ? thisBigIntValue(this value).
+    auto* bigint = TRY(this_bigint_value(global_object, vm.this_value(global_object)));
+
+    // 2. Let numberFormat be ? Construct(%NumberFormat%, « locales, options »).
+    auto* number_format = static_cast<Intl::NumberFormat*>(TRY(construct(global_object, *global_object.intl_number_format_constructor(), locales, options)));
+
+    // 3. Return ? FormatNumeric(numberFormat, x).
+    auto formatted = Intl::format_numeric(global_object, *number_format, bigint);
+    return js_string(vm, move(formatted));
 }
 
 // 21.2.3.4 BigInt.prototype.valueOf ( ), https://tc39.es/ecma262/#sec-bigint.prototype.valueof
diff --git a/Userland/Libraries/LibJS/Tests/builtins/BigInt/BigInt.prototype.toLocaleString.js b/Userland/Libraries/LibJS/Tests/builtins/BigInt/BigInt.prototype.toLocaleString.js
index d7b8b3484a..0fd1692292 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/BigInt/BigInt.prototype.toLocaleString.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/BigInt/BigInt.prototype.toLocaleString.js
@@ -8,3 +8,82 @@ test("calling with non-BigInt |this|", () => {
         BigInt.prototype.toLocaleString.call("foo");
     }).toThrowWithMessage(TypeError, "Not an object of type BigInt");
 });
+
+test("default", () => {
+    expect(1n.toLocaleString("en")).toBe("1");
+    expect(12n.toLocaleString("en")).toBe("12");
+    expect(123n.toLocaleString("en")).toBe("123");
+    expect(123456789123456789123456789123456789n.toLocaleString("en")).toBe(
+        "123,456,789,123,456,789,123,456,789,123,456,789"
+    );
+
+    const ar = new Intl.NumberFormat("ar");
+    expect(1n.toLocaleString("ar")).toBe("\u0661");
+    expect(12n.toLocaleString("ar")).toBe("\u0661\u0662");
+    expect(123n.toLocaleString("ar")).toBe("\u0661\u0662\u0663");
+    expect(123456789123456789123456789123456789n.toLocaleString("ar")).toBe(
+        "\u0661\u0662\u0663\u066c\u0664\u0665\u0666\u066c\u0667\u0668\u0669\u066c\u0661\u0662\u0663\u066c\u0664\u0665\u0666\u066c\u0667\u0668\u0669\u066c\u0661\u0662\u0663\u066c\u0664\u0665\u0666\u066c\u0667\u0668\u0669\u066c\u0661\u0662\u0663\u066c\u0664\u0665\u0666\u066c\u0667\u0668\u0669"
+    );
+});
+
+test("integer digits", () => {
+    expect(1n.toLocaleString("en", { minimumIntegerDigits: 2 })).toBe("01");
+    expect(12n.toLocaleString("en", { minimumIntegerDigits: 2 })).toBe("12");
+    expect(123n.toLocaleString("en", { minimumIntegerDigits: 2 })).toBe("123");
+
+    expect(1n.toLocaleString("ar", { minimumIntegerDigits: 2 })).toBe("\u0660\u0661");
+    expect(12n.toLocaleString("ar", { minimumIntegerDigits: 2 })).toBe("\u0661\u0662");
+    expect(123n.toLocaleString("ar", { minimumIntegerDigits: 2 })).toBe("\u0661\u0662\u0663");
+});
+
+test("significant digits", () => {
+    expect(
+        1n.toLocaleString("en", { minimumSignificantDigits: 4, maximumSignificantDigits: 6 })
+    ).toBe("1.000");
+    expect(
+        12n.toLocaleString("en", { minimumSignificantDigits: 4, maximumSignificantDigits: 6 })
+    ).toBe("12.00");
+    expect(
+        123n.toLocaleString("en", { minimumSignificantDigits: 4, maximumSignificantDigits: 6 })
+    ).toBe("123.0");
+    expect(
+        1234n.toLocaleString("en", { minimumSignificantDigits: 4, maximumSignificantDigits: 6 })
+    ).toBe("1,234");
+    expect(
+        12345n.toLocaleString("en", { minimumSignificantDigits: 4, maximumSignificantDigits: 6 })
+    ).toBe("12,345");
+    expect(
+        123456n.toLocaleString("en", { minimumSignificantDigits: 4, maximumSignificantDigits: 6 })
+    ).toBe("123,456");
+    expect(
+        1234567n.toLocaleString("en", { minimumSignificantDigits: 4, maximumSignificantDigits: 6 })
+    ).toBe("1,234,570");
+    expect(
+        1234561n.toLocaleString("en", { minimumSignificantDigits: 4, maximumSignificantDigits: 6 })
+    ).toBe("1,234,560");
+
+    expect(
+        1n.toLocaleString("ar", { minimumSignificantDigits: 4, maximumSignificantDigits: 6 })
+    ).toBe("\u0661\u066b\u0660\u0660\u0660");
+    expect(
+        12n.toLocaleString("ar", { minimumSignificantDigits: 4, maximumSignificantDigits: 6 })
+    ).toBe("\u0661\u0662\u066b\u0660\u0660");
+    expect(
+        123n.toLocaleString("ar", { minimumSignificantDigits: 4, maximumSignificantDigits: 6 })
+    ).toBe("\u0661\u0662\u0663\u066b\u0660");
+    expect(
+        1234n.toLocaleString("ar", { minimumSignificantDigits: 4, maximumSignificantDigits: 6 })
+    ).toBe("\u0661\u066c\u0662\u0663\u0664");
+    expect(
+        12345n.toLocaleString("ar", { minimumSignificantDigits: 4, maximumSignificantDigits: 6 })
+    ).toBe("\u0661\u0662\u066c\u0663\u0664\u0665");
+    expect(
+        123456n.toLocaleString("ar", { minimumSignificantDigits: 4, maximumSignificantDigits: 6 })
+    ).toBe("\u0661\u0662\u0663\u066c\u0664\u0665\u0666");
+    expect(
+        1234567n.toLocaleString("ar", { minimumSignificantDigits: 4, maximumSignificantDigits: 6 })
+    ).toBe("\u0661\u066c\u0662\u0663\u0664\u066c\u0665\u0667\u0660");
+    expect(
+        1234561n.toLocaleString("ar", { minimumSignificantDigits: 4, maximumSignificantDigits: 6 })
+    ).toBe("\u0661\u066c\u0662\u0663\u0664\u066c\u0665\u0666\u0660");
+});