add --signed flag for binary into int conversions (#11902)

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# Description
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- adds a `--signed` flag to `into int` to allow parsing binary values as
signed integers, the integer size depends on the length of the binary
value

# User-Facing Changes
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helps us keep track of breaking changes. -->
- attempting to convert binary values larger than 8 bytes into integers
now throws an error, with or without `--signed`

# Tests + Formatting
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- wrote 3 tests and 1 example for `into int --signed` usage
- added an example for unsigned binary `into int`

# After Submitting
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- will add examples from this PR to `into int` documentation

crates/nu-command/tests/commands/conversions/into/int.rs

@@ -23,3 +23,21 @@ fn convert_into_int_big_endian() {
     let actual = nu!(r#"0x[01 00 00 00 00 00 00 00] | into int --endian big"#);
     assert_eq!(actual.out, "72057594037927936");
 }
+
+#[test]
+fn convert_into_signed_int_little_endian() {
+    let actual = nu!(r#"0x[ff 00 00 00 00 00 00 00] | into int --endian little --signed"#);
+    assert_eq!(actual.out, "255");
+
+    let actual = nu!(r#"0x[00 00 00 00 00 00 00 ff] | into int --endian little --signed"#);
+    assert_eq!(actual.out, "-72057594037927936");
+}
+
+#[test]
+fn convert_into_signed_int_big_endian() {
+    let actual = nu!(r#"0x[00 00 00 00 00 00 00 ff] | into int --endian big"#);
+    assert_eq!(actual.out, "255");
+
+    let actual = nu!(r#"0x[ff 00 00 00 00 00 00 00] | into int --endian big"#);
+    assert_eq!(actual.out, "-72057594037927936");
+}

crates/nu-command/tests/commands/into_int.rs

@@ -31,6 +31,41 @@ fn into_int_binary() {
     assert!(actual.out.contains("16843009"));
 }
 
+#[test]
+fn into_int_binary_signed() {
+    let actual = nu!("echo 0x[f0] | into int --signed");
+
+    assert!(actual.out.contains("-16"));
+}
+
+#[test]
+fn into_int_binary_back_and_forth() {
+    let actual = nu!("echo 0x[f0] | into int | into binary | to nuon");
+
+    assert!(actual.out.contains("0x[F000000000000000]"));
+}
+
+#[test]
+fn into_int_binary_signed_back_and_forth() {
+    let actual = nu!("echo 0x[f0] | into int --signed | into binary | to nuon");
+
+    assert!(actual.out.contains("0x[F0FFFFFFFFFFFFFF]"));
+}
+
+#[test]
+fn into_int_binary_empty() {
+    let actual = nu!("echo 0x[] | into int");
+
+    assert!(actual.out.contains('0'))
+}
+
+#[test]
+fn into_int_binary_signed_empty() {
+    let actual = nu!("echo 0x[] | into int --signed");
+
+    assert!(actual.out.contains('0'))
+}
+
 #[test]
 #[ignore]
 fn into_int_datetime1() {