From 0c6bcac9978fc6a2b4dd27a681fb5dfabc890b1f Mon Sep 17 00:00:00 2001
From: George Roman <30772943+georgeroman@users.noreply.github.com>
Date: Fri, 16 Oct 2020 12:54:51 +0300
Subject: [PATCH] Support more number literals in BigInt's from string
 constructor (#880)

---
 boa/src/builtins/bigint/conversions.rs | 24 +++++++++++++++++++-----
 boa/src/builtins/bigint/tests.rs       |  4 ++++
 2 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/boa/src/builtins/bigint/conversions.rs b/boa/src/builtins/bigint/conversions.rs
index 88494ad0a5..6cdb1f14f2 100644
--- a/boa/src/builtins/bigint/conversions.rs
+++ b/boa/src/builtins/bigint/conversions.rs
@@ -14,15 +14,29 @@ impl BigInt {
     ///
     /// [spec]: https://tc39.es/ecma262/#sec-stringtobigint
     #[inline]
-    pub(crate) fn from_string(string: &str, _ctx: &mut Context) -> Result<Self, Value> {
-        if string.is_empty() {
+    pub(crate) fn from_string(string: &str, context: &mut Context) -> Result<Self, Value> {
+        if string.trim().is_empty() {
             return Ok(BigInt::from(0));
         }
 
-        match num_bigint::BigInt::from_str(string) {
-            Ok(bigint) => Ok(Self(bigint)),
-            _ => panic!("SyntaxError: cannot convert {} to a BigInt", string),
+        let mut radix = 10;
+        let mut string = string;
+        if string.starts_with("0b") || string.starts_with("0B") {
+            radix = 2;
+            string = &string[2..];
+        }
+        if string.starts_with("0x") || string.starts_with("0X") {
+            radix = 16;
+            string = &string[2..];
         }
+        if string.starts_with("0o") || string.starts_with("0O") {
+            radix = 8;
+            string = &string[2..];
+        }
+
+        BigInt::from_string_radix(string, radix).ok_or_else(|| {
+            context.construct_syntax_error(format!("cannot convert {} to a BigInt", string))
+        })
     }
 
     /// Converts a string to a BigInt with the specified radix.
diff --git a/boa/src/builtins/bigint/tests.rs b/boa/src/builtins/bigint/tests.rs
index 0a7f21113c..0fdf2e52df 100644
--- a/boa/src/builtins/bigint/tests.rs
+++ b/boa/src/builtins/bigint/tests.rs
@@ -133,6 +133,7 @@ fn bigint_function_conversion_from_string() {
     let mut engine = Context::new();
 
     assert_eq!(forward(&mut engine, "BigInt('')"), "0n");
+    assert_eq!(forward(&mut engine, "BigInt('   ')"), "0n");
     assert_eq!(
         forward(&mut engine, "BigInt('200000000000000000')"),
         "200000000000000000n"
@@ -141,6 +142,9 @@ fn bigint_function_conversion_from_string() {
         forward(&mut engine, "BigInt('1000000000000000000000000000000000')"),
         "1000000000000000000000000000000000n"
     );
+    assert_eq!(forward(&mut engine, "BigInt('0b1111')"), "15n");
+    assert_eq!(forward(&mut engine, "BigInt('0o70')"), "56n");
+    assert_eq!(forward(&mut engine, "BigInt('0xFF')"), "255n");
 }
 
 #[test]