RUST-1992 Introduce the &CStr and CString types for keys and regular expressions
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abr-egn
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&CStr and CString types for regular expressions&CStr and CString types for keys and regular expressions
| doc_buf.append("number", 12).unwrap(); | ||
| doc_buf.append("bool", false).unwrap(); | ||
| doc_buf.append("nu", RawBson::Null).unwrap(); | ||
| doc_buf.append(cstr!("a"), "key"); |
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This really is the whole story in this one line - the failure point has been shifted from writing bytes to the document buffer (append and everything that used it) to constructing the string, and that in turn can now be done either at run-time or at compile-time if it's just a literal.
| ("a key", RawBson::String("a value".to_string())), | ||
| ("an objectid", RawBson::ObjectId(oid)), | ||
| ("a date", RawBson::DateTime(dt)), | ||
| (cstr!("a key"), RawBson::String("a value".to_string())), |
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Building from a key-value list is one place where the repeated cstr! is more of a hassle; I could potentially see providing a convenience try_from_iter method that accepts &str keys and returns a Result (i.e. like this used to be).
| // Insert the current entry followed by trailing comma. | ||
| (@object $object:ident [$($key:tt)+] ($value:expr) , $($rest:tt)*) => { | ||
| $object.append(($($key)+), $value).expect("invalid bson value"); | ||
| // Insert the current entry with followed by trailing comma, with a key literal. |
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I tweaked the behavior of rawdoc! a bit here - now if the key is a literal it'll be implicitly wrapped in cstr! so it gets compile-time validated, otherwise it'll be assumed to be an expression that evaluates to a valid key and passed on to append (as before). The main difference here is that now this macro can no longer panic :)
| } | ||
| } | ||
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| impl<B: BindRawBsonRef> FromIterator<B> for RawArrayBuf { |
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This gets to be a real impl again 🎉
| @@ -256,7 +256,13 @@ impl<'a> RawBsonRef<'a> { | |||
| RawBsonRef::Boolean(b) => RawBson::Boolean(b), | |||
| RawBsonRef::Null => RawBson::Null, | |||
| RawBsonRef::RegularExpression(re) => { | |||
| RawBson::RegularExpression(Regex::new(re.pattern, re.options)) | |||
| let mut chars: Vec<_> = re.options.as_str().chars().collect(); | |||
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This doesn't use Regex::from_strings because it's coming from already-validated data, so it can skip the extra validation step that would add.
RUST-1992
This introduces the
&CStrandCStringtypes; these are zero-overhead equivalents to&strandStringthat witness that the text contain no zero bytes. These types are used to enforce that zero-byte checking is done for regular expressions and value keys at construction time (i.e. load or user input) rather than at encoding, which means (a) errors will happen closer to the root cause and (b) the encoding machinery can be simplified.The new types are made fairly easy to work with via implementation of a swath of standard library traits and a
cstr!macro that checks at compile-time if a given string literal is valid and errors with a friendly message if not.