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-rw-r--r--library/alloc/tests/string.rs876
1 files changed, 876 insertions, 0 deletions
diff --git a/library/alloc/tests/string.rs b/library/alloc/tests/string.rs
new file mode 100644
index 000000000..b6836fdc8
--- /dev/null
+++ b/library/alloc/tests/string.rs
@@ -0,0 +1,876 @@
+use std::assert_matches::assert_matches;
+use std::borrow::Cow;
+use std::cell::Cell;
+use std::collections::TryReserveErrorKind::*;
+use std::ops::Bound;
+use std::ops::Bound::*;
+use std::ops::RangeBounds;
+use std::panic;
+use std::str;
+
+pub trait IntoCow<'a, B: ?Sized>
+where
+ B: ToOwned,
+{
+ fn into_cow(self) -> Cow<'a, B>;
+}
+
+impl<'a> IntoCow<'a, str> for String {
+ fn into_cow(self) -> Cow<'a, str> {
+ Cow::Owned(self)
+ }
+}
+
+impl<'a> IntoCow<'a, str> for &'a str {
+ fn into_cow(self) -> Cow<'a, str> {
+ Cow::Borrowed(self)
+ }
+}
+
+#[test]
+fn test_from_str() {
+ let owned: Option<std::string::String> = "string".parse().ok();
+ assert_eq!(owned.as_ref().map(|s| &**s), Some("string"));
+}
+
+#[test]
+fn test_from_cow_str() {
+ assert_eq!(String::from(Cow::Borrowed("string")), "string");
+ assert_eq!(String::from(Cow::Owned(String::from("string"))), "string");
+}
+
+#[test]
+fn test_unsized_to_string() {
+ let s: &str = "abc";
+ let _: String = (*s).to_string();
+}
+
+#[test]
+fn test_from_utf8() {
+ let xs = b"hello".to_vec();
+ assert_eq!(String::from_utf8(xs).unwrap(), String::from("hello"));
+
+ let xs = "ศไทย中华Việt Nam".as_bytes().to_vec();
+ assert_eq!(String::from_utf8(xs).unwrap(), String::from("ศไทย中华Việt Nam"));
+
+ let xs = b"hello\xFF".to_vec();
+ let err = String::from_utf8(xs).unwrap_err();
+ assert_eq!(err.as_bytes(), b"hello\xff");
+ let err_clone = err.clone();
+ assert_eq!(err, err_clone);
+ assert_eq!(err.into_bytes(), b"hello\xff".to_vec());
+ assert_eq!(err_clone.utf8_error().valid_up_to(), 5);
+}
+
+#[test]
+fn test_from_utf8_lossy() {
+ let xs = b"hello";
+ let ys: Cow<'_, str> = "hello".into_cow();
+ assert_eq!(String::from_utf8_lossy(xs), ys);
+
+ let xs = "ศไทย中华Việt Nam".as_bytes();
+ let ys: Cow<'_, str> = "ศไทย中华Việt Nam".into_cow();
+ assert_eq!(String::from_utf8_lossy(xs), ys);
+
+ let xs = b"Hello\xC2 There\xFF Goodbye";
+ assert_eq!(
+ String::from_utf8_lossy(xs),
+ String::from("Hello\u{FFFD} There\u{FFFD} Goodbye").into_cow()
+ );
+
+ let xs = b"Hello\xC0\x80 There\xE6\x83 Goodbye";
+ assert_eq!(
+ String::from_utf8_lossy(xs),
+ String::from("Hello\u{FFFD}\u{FFFD} There\u{FFFD} Goodbye").into_cow()
+ );
+
+ let xs = b"\xF5foo\xF5\x80bar";
+ assert_eq!(
+ String::from_utf8_lossy(xs),
+ String::from("\u{FFFD}foo\u{FFFD}\u{FFFD}bar").into_cow()
+ );
+
+ let xs = b"\xF1foo\xF1\x80bar\xF1\x80\x80baz";
+ assert_eq!(
+ String::from_utf8_lossy(xs),
+ String::from("\u{FFFD}foo\u{FFFD}bar\u{FFFD}baz").into_cow()
+ );
+
+ let xs = b"\xF4foo\xF4\x80bar\xF4\xBFbaz";
+ assert_eq!(
+ String::from_utf8_lossy(xs),
+ String::from("\u{FFFD}foo\u{FFFD}bar\u{FFFD}\u{FFFD}baz").into_cow()
+ );
+
+ let xs = b"\xF0\x80\x80\x80foo\xF0\x90\x80\x80bar";
+ assert_eq!(
+ String::from_utf8_lossy(xs),
+ String::from("\u{FFFD}\u{FFFD}\u{FFFD}\u{FFFD}foo\u{10000}bar").into_cow()
+ );
+
+ // surrogates
+ let xs = b"\xED\xA0\x80foo\xED\xBF\xBFbar";
+ assert_eq!(
+ String::from_utf8_lossy(xs),
+ String::from("\u{FFFD}\u{FFFD}\u{FFFD}foo\u{FFFD}\u{FFFD}\u{FFFD}bar").into_cow()
+ );
+}
+
+#[test]
+fn test_from_utf16() {
+ let pairs = [
+ (
+ String::from("𐍅𐌿𐌻𐍆𐌹𐌻𐌰\n"),
+ vec![
+ 0xd800, 0xdf45, 0xd800, 0xdf3f, 0xd800, 0xdf3b, 0xd800, 0xdf46, 0xd800, 0xdf39,
+ 0xd800, 0xdf3b, 0xd800, 0xdf30, 0x000a,
+ ],
+ ),
+ (
+ String::from("𐐒𐑉𐐮𐑀𐐲𐑋 𐐏𐐲𐑍\n"),
+ vec![
+ 0xd801, 0xdc12, 0xd801, 0xdc49, 0xd801, 0xdc2e, 0xd801, 0xdc40, 0xd801, 0xdc32,
+ 0xd801, 0xdc4b, 0x0020, 0xd801, 0xdc0f, 0xd801, 0xdc32, 0xd801, 0xdc4d, 0x000a,
+ ],
+ ),
+ (
+ String::from("𐌀𐌖𐌋𐌄𐌑𐌉·𐌌𐌄𐌕𐌄𐌋𐌉𐌑\n"),
+ vec![
+ 0xd800, 0xdf00, 0xd800, 0xdf16, 0xd800, 0xdf0b, 0xd800, 0xdf04, 0xd800, 0xdf11,
+ 0xd800, 0xdf09, 0x00b7, 0xd800, 0xdf0c, 0xd800, 0xdf04, 0xd800, 0xdf15, 0xd800,
+ 0xdf04, 0xd800, 0xdf0b, 0xd800, 0xdf09, 0xd800, 0xdf11, 0x000a,
+ ],
+ ),
+ (
+ String::from("𐒋𐒘𐒈𐒑𐒛𐒒 𐒕𐒓 𐒈𐒚𐒍 𐒏𐒜𐒒𐒖𐒆 𐒕𐒆\n"),
+ vec![
+ 0xd801, 0xdc8b, 0xd801, 0xdc98, 0xd801, 0xdc88, 0xd801, 0xdc91, 0xd801, 0xdc9b,
+ 0xd801, 0xdc92, 0x0020, 0xd801, 0xdc95, 0xd801, 0xdc93, 0x0020, 0xd801, 0xdc88,
+ 0xd801, 0xdc9a, 0xd801, 0xdc8d, 0x0020, 0xd801, 0xdc8f, 0xd801, 0xdc9c, 0xd801,
+ 0xdc92, 0xd801, 0xdc96, 0xd801, 0xdc86, 0x0020, 0xd801, 0xdc95, 0xd801, 0xdc86,
+ 0x000a,
+ ],
+ ),
+ // Issue #12318, even-numbered non-BMP planes
+ (String::from("\u{20000}"), vec![0xD840, 0xDC00]),
+ ];
+
+ for p in &pairs {
+ let (s, u) = (*p).clone();
+ let s_as_utf16 = s.encode_utf16().collect::<Vec<u16>>();
+ let u_as_string = String::from_utf16(&u).unwrap();
+
+ assert!(core::char::decode_utf16(u.iter().cloned()).all(|r| r.is_ok()));
+ assert_eq!(s_as_utf16, u);
+
+ assert_eq!(u_as_string, s);
+ assert_eq!(String::from_utf16_lossy(&u), s);
+
+ assert_eq!(String::from_utf16(&s_as_utf16).unwrap(), s);
+ assert_eq!(u_as_string.encode_utf16().collect::<Vec<u16>>(), u);
+ }
+}
+
+#[test]
+fn test_utf16_invalid() {
+ // completely positive cases tested above.
+ // lead + eof
+ assert!(String::from_utf16(&[0xD800]).is_err());
+ // lead + lead
+ assert!(String::from_utf16(&[0xD800, 0xD800]).is_err());
+
+ // isolated trail
+ assert!(String::from_utf16(&[0x0061, 0xDC00]).is_err());
+
+ // general
+ assert!(String::from_utf16(&[0xD800, 0xd801, 0xdc8b, 0xD800]).is_err());
+}
+
+#[test]
+fn test_from_utf16_lossy() {
+ // completely positive cases tested above.
+ // lead + eof
+ assert_eq!(String::from_utf16_lossy(&[0xD800]), String::from("\u{FFFD}"));
+ // lead + lead
+ assert_eq!(String::from_utf16_lossy(&[0xD800, 0xD800]), String::from("\u{FFFD}\u{FFFD}"));
+
+ // isolated trail
+ assert_eq!(String::from_utf16_lossy(&[0x0061, 0xDC00]), String::from("a\u{FFFD}"));
+
+ // general
+ assert_eq!(
+ String::from_utf16_lossy(&[0xD800, 0xd801, 0xdc8b, 0xD800]),
+ String::from("\u{FFFD}𐒋\u{FFFD}")
+ );
+}
+
+#[test]
+fn test_push_bytes() {
+ let mut s = String::from("ABC");
+ unsafe {
+ let mv = s.as_mut_vec();
+ mv.extend_from_slice(&[b'D']);
+ }
+ assert_eq!(s, "ABCD");
+}
+
+#[test]
+fn test_push_str() {
+ let mut s = String::new();
+ s.push_str("");
+ assert_eq!(&s[0..], "");
+ s.push_str("abc");
+ assert_eq!(&s[0..], "abc");
+ s.push_str("ประเทศไทย中华Việt Nam");
+ assert_eq!(&s[0..], "abcประเทศไทย中华Việt Nam");
+}
+
+#[test]
+fn test_add_assign() {
+ let mut s = String::new();
+ s += "";
+ assert_eq!(s.as_str(), "");
+ s += "abc";
+ assert_eq!(s.as_str(), "abc");
+ s += "ประเทศไทย中华Việt Nam";
+ assert_eq!(s.as_str(), "abcประเทศไทย中华Việt Nam");
+}
+
+#[test]
+fn test_push() {
+ let mut data = String::from("ประเทศไทย中");
+ data.push('华');
+ data.push('b'); // 1 byte
+ data.push('¢'); // 2 byte
+ data.push('€'); // 3 byte
+ data.push('𤭢'); // 4 byte
+ assert_eq!(data, "ประเทศไทย中华b¢€𤭢");
+}
+
+#[test]
+fn test_pop() {
+ let mut data = String::from("ประเทศไทย中华b¢€𤭢");
+ assert_eq!(data.pop().unwrap(), '𤭢'); // 4 bytes
+ assert_eq!(data.pop().unwrap(), '€'); // 3 bytes
+ assert_eq!(data.pop().unwrap(), '¢'); // 2 bytes
+ assert_eq!(data.pop().unwrap(), 'b'); // 1 bytes
+ assert_eq!(data.pop().unwrap(), '华');
+ assert_eq!(data, "ประเทศไทย中");
+}
+
+#[test]
+fn test_split_off_empty() {
+ let orig = "Hello, world!";
+ let mut split = String::from(orig);
+ let empty: String = split.split_off(orig.len());
+ assert!(empty.is_empty());
+}
+
+#[test]
+#[should_panic]
+fn test_split_off_past_end() {
+ let orig = "Hello, world!";
+ let mut split = String::from(orig);
+ let _ = split.split_off(orig.len() + 1);
+}
+
+#[test]
+#[should_panic]
+fn test_split_off_mid_char() {
+ let mut shan = String::from("山");
+ let _broken_mountain = shan.split_off(1);
+}
+
+#[test]
+fn test_split_off_ascii() {
+ let mut ab = String::from("ABCD");
+ let orig_capacity = ab.capacity();
+ let cd = ab.split_off(2);
+ assert_eq!(ab, "AB");
+ assert_eq!(cd, "CD");
+ assert_eq!(ab.capacity(), orig_capacity);
+}
+
+#[test]
+fn test_split_off_unicode() {
+ let mut nihon = String::from("日本語");
+ let orig_capacity = nihon.capacity();
+ let go = nihon.split_off("日本".len());
+ assert_eq!(nihon, "日本");
+ assert_eq!(go, "語");
+ assert_eq!(nihon.capacity(), orig_capacity);
+}
+
+#[test]
+fn test_str_truncate() {
+ let mut s = String::from("12345");
+ s.truncate(5);
+ assert_eq!(s, "12345");
+ s.truncate(3);
+ assert_eq!(s, "123");
+ s.truncate(0);
+ assert_eq!(s, "");
+
+ let mut s = String::from("12345");
+ let p = s.as_ptr();
+ s.truncate(3);
+ s.push_str("6");
+ let p_ = s.as_ptr();
+ assert_eq!(p_, p);
+}
+
+#[test]
+fn test_str_truncate_invalid_len() {
+ let mut s = String::from("12345");
+ s.truncate(6);
+ assert_eq!(s, "12345");
+}
+
+#[test]
+#[should_panic]
+fn test_str_truncate_split_codepoint() {
+ let mut s = String::from("\u{FC}"); // ü
+ s.truncate(1);
+}
+
+#[test]
+fn test_str_clear() {
+ let mut s = String::from("12345");
+ s.clear();
+ assert_eq!(s.len(), 0);
+ assert_eq!(s, "");
+}
+
+#[test]
+fn test_str_add() {
+ let a = String::from("12345");
+ let b = a + "2";
+ let b = b + "2";
+ assert_eq!(b.len(), 7);
+ assert_eq!(b, "1234522");
+}
+
+#[test]
+fn remove() {
+ let mut s = "ศไทย中华Việt Nam; foobar".to_string();
+ assert_eq!(s.remove(0), 'ศ');
+ assert_eq!(s.len(), 33);
+ assert_eq!(s, "ไทย中华Việt Nam; foobar");
+ assert_eq!(s.remove(17), 'ệ');
+ assert_eq!(s, "ไทย中华Vit Nam; foobar");
+}
+
+#[test]
+#[should_panic]
+fn remove_bad() {
+ "ศ".to_string().remove(1);
+}
+
+#[test]
+fn test_remove_matches() {
+ let mut s = "abc".to_string();
+
+ s.remove_matches('b');
+ assert_eq!(s, "ac");
+ s.remove_matches('b');
+ assert_eq!(s, "ac");
+
+ let mut s = "abcb".to_string();
+
+ s.remove_matches('b');
+ assert_eq!(s, "ac");
+
+ let mut s = "ศไทย中华Việt Nam; foobarศ".to_string();
+ s.remove_matches('ศ');
+ assert_eq!(s, "ไทย中华Việt Nam; foobar");
+
+ let mut s = "".to_string();
+ s.remove_matches("");
+ assert_eq!(s, "");
+
+ let mut s = "aaaaa".to_string();
+ s.remove_matches('a');
+ assert_eq!(s, "");
+}
+
+#[test]
+fn test_retain() {
+ let mut s = String::from("α_β_γ");
+
+ s.retain(|_| true);
+ assert_eq!(s, "α_β_γ");
+
+ s.retain(|c| c != '_');
+ assert_eq!(s, "αβγ");
+
+ s.retain(|c| c != 'β');
+ assert_eq!(s, "αγ");
+
+ s.retain(|c| c == 'α');
+ assert_eq!(s, "α");
+
+ s.retain(|_| false);
+ assert_eq!(s, "");
+
+ let mut s = String::from("0è0");
+ let _ = panic::catch_unwind(panic::AssertUnwindSafe(|| {
+ let mut count = 0;
+ s.retain(|_| {
+ count += 1;
+ match count {
+ 1 => false,
+ 2 => true,
+ _ => panic!(),
+ }
+ });
+ }));
+ assert!(std::str::from_utf8(s.as_bytes()).is_ok());
+}
+
+#[test]
+fn insert() {
+ let mut s = "foobar".to_string();
+ s.insert(0, 'ệ');
+ assert_eq!(s, "ệfoobar");
+ s.insert(6, 'ย');
+ assert_eq!(s, "ệfooยbar");
+}
+
+#[test]
+#[should_panic]
+fn insert_bad1() {
+ "".to_string().insert(1, 't');
+}
+#[test]
+#[should_panic]
+fn insert_bad2() {
+ "ệ".to_string().insert(1, 't');
+}
+
+#[test]
+fn test_slicing() {
+ let s = "foobar".to_string();
+ assert_eq!("foobar", &s[..]);
+ assert_eq!("foo", &s[..3]);
+ assert_eq!("bar", &s[3..]);
+ assert_eq!("oob", &s[1..4]);
+}
+
+#[test]
+fn test_simple_types() {
+ assert_eq!(1.to_string(), "1");
+ assert_eq!((-1).to_string(), "-1");
+ assert_eq!(200.to_string(), "200");
+ assert_eq!(2.to_string(), "2");
+ assert_eq!(true.to_string(), "true");
+ assert_eq!(false.to_string(), "false");
+ assert_eq!(("hi".to_string()).to_string(), "hi");
+}
+
+#[test]
+fn test_vectors() {
+ let x: Vec<i32> = vec![];
+ assert_eq!(format!("{x:?}"), "[]");
+ assert_eq!(format!("{:?}", vec![1]), "[1]");
+ assert_eq!(format!("{:?}", vec![1, 2, 3]), "[1, 2, 3]");
+ assert!(format!("{:?}", vec![vec![], vec![1], vec![1, 1]]) == "[[], [1], [1, 1]]");
+}
+
+#[test]
+fn test_from_iterator() {
+ let s = "ศไทย中华Việt Nam".to_string();
+ let t = "ศไทย中华";
+ let u = "Việt Nam";
+
+ let a: String = s.chars().collect();
+ assert_eq!(s, a);
+
+ let mut b = t.to_string();
+ b.extend(u.chars());
+ assert_eq!(s, b);
+
+ let c: String = [t, u].into_iter().collect();
+ assert_eq!(s, c);
+
+ let mut d = t.to_string();
+ d.extend(vec![u]);
+ assert_eq!(s, d);
+}
+
+#[test]
+fn test_drain() {
+ let mut s = String::from("αβγ");
+ assert_eq!(s.drain(2..4).collect::<String>(), "β");
+ assert_eq!(s, "αγ");
+
+ let mut t = String::from("abcd");
+ t.drain(..0);
+ assert_eq!(t, "abcd");
+ t.drain(..1);
+ assert_eq!(t, "bcd");
+ t.drain(3..);
+ assert_eq!(t, "bcd");
+ t.drain(..);
+ assert_eq!(t, "");
+}
+
+#[test]
+#[should_panic]
+fn test_drain_start_overflow() {
+ let mut s = String::from("abc");
+ s.drain((Excluded(usize::MAX), Included(0)));
+}
+
+#[test]
+#[should_panic]
+fn test_drain_end_overflow() {
+ let mut s = String::from("abc");
+ s.drain((Included(0), Included(usize::MAX)));
+}
+
+#[test]
+fn test_replace_range() {
+ let mut s = "Hello, world!".to_owned();
+ s.replace_range(7..12, "世界");
+ assert_eq!(s, "Hello, 世界!");
+}
+
+#[test]
+#[should_panic]
+fn test_replace_range_char_boundary() {
+ let mut s = "Hello, 世界!".to_owned();
+ s.replace_range(..8, "");
+}
+
+#[test]
+fn test_replace_range_inclusive_range() {
+ let mut v = String::from("12345");
+ v.replace_range(2..=3, "789");
+ assert_eq!(v, "127895");
+ v.replace_range(1..=2, "A");
+ assert_eq!(v, "1A895");
+}
+
+#[test]
+#[should_panic]
+fn test_replace_range_out_of_bounds() {
+ let mut s = String::from("12345");
+ s.replace_range(5..6, "789");
+}
+
+#[test]
+#[should_panic]
+fn test_replace_range_inclusive_out_of_bounds() {
+ let mut s = String::from("12345");
+ s.replace_range(5..=5, "789");
+}
+
+#[test]
+#[should_panic]
+fn test_replace_range_start_overflow() {
+ let mut s = String::from("123");
+ s.replace_range((Excluded(usize::MAX), Included(0)), "");
+}
+
+#[test]
+#[should_panic]
+fn test_replace_range_end_overflow() {
+ let mut s = String::from("456");
+ s.replace_range((Included(0), Included(usize::MAX)), "");
+}
+
+#[test]
+fn test_replace_range_empty() {
+ let mut s = String::from("12345");
+ s.replace_range(1..2, "");
+ assert_eq!(s, "1345");
+}
+
+#[test]
+fn test_replace_range_unbounded() {
+ let mut s = String::from("12345");
+ s.replace_range(.., "");
+ assert_eq!(s, "");
+}
+
+#[test]
+fn test_replace_range_evil_start_bound() {
+ struct EvilRange(Cell<bool>);
+
+ impl RangeBounds<usize> for EvilRange {
+ fn start_bound(&self) -> Bound<&usize> {
+ Bound::Included(if self.0.get() {
+ &1
+ } else {
+ self.0.set(true);
+ &0
+ })
+ }
+ fn end_bound(&self) -> Bound<&usize> {
+ Bound::Unbounded
+ }
+ }
+
+ let mut s = String::from("🦀");
+ s.replace_range(EvilRange(Cell::new(false)), "");
+ assert_eq!(Ok(""), str::from_utf8(s.as_bytes()));
+}
+
+#[test]
+fn test_replace_range_evil_end_bound() {
+ struct EvilRange(Cell<bool>);
+
+ impl RangeBounds<usize> for EvilRange {
+ fn start_bound(&self) -> Bound<&usize> {
+ Bound::Included(&0)
+ }
+ fn end_bound(&self) -> Bound<&usize> {
+ Bound::Excluded(if self.0.get() {
+ &3
+ } else {
+ self.0.set(true);
+ &4
+ })
+ }
+ }
+
+ let mut s = String::from("🦀");
+ s.replace_range(EvilRange(Cell::new(false)), "");
+ assert_eq!(Ok(""), str::from_utf8(s.as_bytes()));
+}
+
+#[test]
+fn test_extend_ref() {
+ let mut a = "foo".to_string();
+ a.extend(&['b', 'a', 'r']);
+
+ assert_eq!(&a, "foobar");
+}
+
+#[test]
+fn test_into_boxed_str() {
+ let xs = String::from("hello my name is bob");
+ let ys = xs.into_boxed_str();
+ assert_eq!(&*ys, "hello my name is bob");
+}
+
+#[test]
+fn test_reserve_exact() {
+ // This is all the same as test_reserve
+
+ let mut s = String::new();
+ assert_eq!(s.capacity(), 0);
+
+ s.reserve_exact(2);
+ assert!(s.capacity() >= 2);
+
+ for _i in 0..16 {
+ s.push('0');
+ }
+
+ assert!(s.capacity() >= 16);
+ s.reserve_exact(16);
+ assert!(s.capacity() >= 32);
+
+ s.push('0');
+
+ s.reserve_exact(16);
+ assert!(s.capacity() >= 33)
+}
+
+#[test]
+#[cfg_attr(miri, ignore)] // Miri does not support signalling OOM
+#[cfg_attr(target_os = "android", ignore)] // Android used in CI has a broken dlmalloc
+fn test_try_reserve() {
+ // These are the interesting cases:
+ // * exactly isize::MAX should never trigger a CapacityOverflow (can be OOM)
+ // * > isize::MAX should always fail
+ // * On 16/32-bit should CapacityOverflow
+ // * On 64-bit should OOM
+ // * overflow may trigger when adding `len` to `cap` (in number of elements)
+ // * overflow may trigger when multiplying `new_cap` by size_of::<T> (to get bytes)
+
+ const MAX_CAP: usize = isize::MAX as usize;
+ const MAX_USIZE: usize = usize::MAX;
+
+ // On 16/32-bit, we check that allocations don't exceed isize::MAX,
+ // on 64-bit, we assume the OS will give an OOM for such a ridiculous size.
+ // Any platform that succeeds for these requests is technically broken with
+ // ptr::offset because LLVM is the worst.
+ let guards_against_isize = usize::BITS < 64;
+
+ {
+ // Note: basic stuff is checked by test_reserve
+ let mut empty_string: String = String::new();
+
+ // Check isize::MAX doesn't count as an overflow
+ if let Err(CapacityOverflow) = empty_string.try_reserve(MAX_CAP).map_err(|e| e.kind()) {
+ panic!("isize::MAX shouldn't trigger an overflow!");
+ }
+ // Play it again, frank! (just to be sure)
+ if let Err(CapacityOverflow) = empty_string.try_reserve(MAX_CAP).map_err(|e| e.kind()) {
+ panic!("isize::MAX shouldn't trigger an overflow!");
+ }
+
+ if guards_against_isize {
+ // Check isize::MAX + 1 does count as overflow
+ assert_matches!(
+ empty_string.try_reserve(MAX_CAP + 1).map_err(|e| e.kind()),
+ Err(CapacityOverflow),
+ "isize::MAX + 1 should trigger an overflow!"
+ );
+
+ // Check usize::MAX does count as overflow
+ assert_matches!(
+ empty_string.try_reserve(MAX_USIZE).map_err(|e| e.kind()),
+ Err(CapacityOverflow),
+ "usize::MAX should trigger an overflow!"
+ );
+ } else {
+ // Check isize::MAX + 1 is an OOM
+ assert_matches!(
+ empty_string.try_reserve(MAX_CAP + 1).map_err(|e| e.kind()),
+ Err(AllocError { .. }),
+ "isize::MAX + 1 should trigger an OOM!"
+ );
+
+ // Check usize::MAX is an OOM
+ assert_matches!(
+ empty_string.try_reserve(MAX_USIZE).map_err(|e| e.kind()),
+ Err(AllocError { .. }),
+ "usize::MAX should trigger an OOM!"
+ );
+ }
+ }
+
+ {
+ // Same basic idea, but with non-zero len
+ let mut ten_bytes: String = String::from("0123456789");
+
+ if let Err(CapacityOverflow) = ten_bytes.try_reserve(MAX_CAP - 10).map_err(|e| e.kind()) {
+ panic!("isize::MAX shouldn't trigger an overflow!");
+ }
+ if let Err(CapacityOverflow) = ten_bytes.try_reserve(MAX_CAP - 10).map_err(|e| e.kind()) {
+ panic!("isize::MAX shouldn't trigger an overflow!");
+ }
+ if guards_against_isize {
+ assert_matches!(
+ ten_bytes.try_reserve(MAX_CAP - 9).map_err(|e| e.kind()),
+ Err(CapacityOverflow),
+ "isize::MAX + 1 should trigger an overflow!"
+ );
+ } else {
+ assert_matches!(
+ ten_bytes.try_reserve(MAX_CAP - 9).map_err(|e| e.kind()),
+ Err(AllocError { .. }),
+ "isize::MAX + 1 should trigger an OOM!"
+ );
+ }
+ // Should always overflow in the add-to-len
+ assert_matches!(
+ ten_bytes.try_reserve(MAX_USIZE).map_err(|e| e.kind()),
+ Err(CapacityOverflow),
+ "usize::MAX should trigger an overflow!"
+ );
+ }
+}
+
+#[test]
+#[cfg_attr(miri, ignore)] // Miri does not support signalling OOM
+#[cfg_attr(target_os = "android", ignore)] // Android used in CI has a broken dlmalloc
+fn test_try_reserve_exact() {
+ // This is exactly the same as test_try_reserve with the method changed.
+ // See that test for comments.
+
+ const MAX_CAP: usize = isize::MAX as usize;
+ const MAX_USIZE: usize = usize::MAX;
+
+ let guards_against_isize = usize::BITS < 64;
+
+ {
+ let mut empty_string: String = String::new();
+
+ if let Err(CapacityOverflow) = empty_string.try_reserve_exact(MAX_CAP).map_err(|e| e.kind())
+ {
+ panic!("isize::MAX shouldn't trigger an overflow!");
+ }
+ if let Err(CapacityOverflow) = empty_string.try_reserve_exact(MAX_CAP).map_err(|e| e.kind())
+ {
+ panic!("isize::MAX shouldn't trigger an overflow!");
+ }
+
+ if guards_against_isize {
+ assert_matches!(
+ empty_string.try_reserve_exact(MAX_CAP + 1).map_err(|e| e.kind()),
+ Err(CapacityOverflow),
+ "isize::MAX + 1 should trigger an overflow!"
+ );
+
+ assert_matches!(
+ empty_string.try_reserve_exact(MAX_USIZE).map_err(|e| e.kind()),
+ Err(CapacityOverflow),
+ "usize::MAX should trigger an overflow!"
+ );
+ } else {
+ assert_matches!(
+ empty_string.try_reserve_exact(MAX_CAP + 1).map_err(|e| e.kind()),
+ Err(AllocError { .. }),
+ "isize::MAX + 1 should trigger an OOM!"
+ );
+
+ assert_matches!(
+ empty_string.try_reserve_exact(MAX_USIZE).map_err(|e| e.kind()),
+ Err(AllocError { .. }),
+ "usize::MAX should trigger an OOM!"
+ );
+ }
+ }
+
+ {
+ let mut ten_bytes: String = String::from("0123456789");
+
+ if let Err(CapacityOverflow) =
+ ten_bytes.try_reserve_exact(MAX_CAP - 10).map_err(|e| e.kind())
+ {
+ panic!("isize::MAX shouldn't trigger an overflow!");
+ }
+ if let Err(CapacityOverflow) =
+ ten_bytes.try_reserve_exact(MAX_CAP - 10).map_err(|e| e.kind())
+ {
+ panic!("isize::MAX shouldn't trigger an overflow!");
+ }
+ if guards_against_isize {
+ assert_matches!(
+ ten_bytes.try_reserve_exact(MAX_CAP - 9).map_err(|e| e.kind()),
+ Err(CapacityOverflow),
+ "isize::MAX + 1 should trigger an overflow!"
+ );
+ } else {
+ assert_matches!(
+ ten_bytes.try_reserve_exact(MAX_CAP - 9).map_err(|e| e.kind()),
+ Err(AllocError { .. }),
+ "isize::MAX + 1 should trigger an OOM!"
+ );
+ }
+ assert_matches!(
+ ten_bytes.try_reserve_exact(MAX_USIZE).map_err(|e| e.kind()),
+ Err(CapacityOverflow),
+ "usize::MAX should trigger an overflow!"
+ );
+ }
+}
+
+#[test]
+fn test_from_char() {
+ assert_eq!(String::from('a'), 'a'.to_string());
+ let s: String = 'x'.into();
+ assert_eq!(s, 'x'.to_string());
+}
+
+#[test]
+fn test_str_concat() {
+ let a: String = "hello".to_string();
+ let b: String = "world".to_string();
+ let s: String = format!("{a}{b}");
+ assert_eq!(s.as_bytes()[9], 'd' as u8);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-02 02:41:03 +0000