134     /// Supplied bytes contain an interior `NUL`.
137     /// Supplied bytes are not terminated by `NUL`.
148 /// A string that is guaranteed to have exactly one `NUL` byte, which is at the
156     /// Returns the length of this string excluding `NUL`.
162     /// Returns the length of this string with `NUL`.
174     /// Returns `true` if the string only includes `NUL`.
184     /// `ptr` must be a valid pointer to a `NUL`-terminated C string, and it must
190         // to a `NUL`-terminated C string.  in from_char_ptr()
194         // SAFETY: As `len` is returned by `strlen`, `bytes` does not contain interior `NUL`.  in from_char_ptr()
195         // As we have added 1 to `len`, the last byte is known to be `NUL`.  in from_char_ptr()
201     /// The provided slice must be `NUL`-terminated, does not contain any
202     /// interior `NUL` bytes.
228     /// `bytes` *must* end with a `NUL` byte, and should only have a single
229     /// `NUL` byte (or the string will be truncated).
241     /// `bytes` *must* end with a `NUL` byte, and should only have a single
242     /// `NUL` byte (or the string will be truncated).
255     /// Convert the string to a byte slice without the trailing `NUL` byte.
261     /// Convert the string to a byte slice containing the trailing `NUL` byte.
323         // INVARIANT: This doesn't introduce or remove NUL bytes in the C  in make_ascii_lowercase()
338         // INVARIANT: This doesn't introduce or remove NUL bytes in the C  in make_ascii_uppercase()
503 /// The string literal should not contain any `NUL` bytes.
518             Err(_) => panic!("string contains interior NUL"),
768 /// An owned string that is guaranteed to have exactly one `NUL` byte, which is at the end.
774 /// The string is always `NUL`-terminated and contains no other `NUL` bytes.
788 /// // This fails because it has an embedded `NUL` byte.
799         // Calculate the size needed (formatted string plus `NUL` terminator).  in try_from_fmt()
816         // Check that there are no `NUL` bytes before the end.  in try_from_fmt()
818         // (which the minimum buffer size) and is non-zero (we wrote at least the `NUL` terminator)  in try_from_fmt()
825         // INVARIANT: We wrote the `NUL` terminator and checked above that no other `NUL` bytes  in try_from_fmt()
835         // SAFETY: The type invariants guarantee that the string is `NUL`-terminated and that no  in deref()
836         // other `NUL` bytes exist.  in deref()
843         // SAFETY: A `CString` is always NUL-terminated and contains no other  in deref_mut()
844         // NUL bytes.  in deref_mut()