use crate::callsite;
use crate::stdlib::{
borrow::Borrow,
fmt,
hash::{Hash, Hasher},
ops::Range,
};
use self::private::ValidLen;
#[derive(Debug)]
pub struct Field {
i: usize,
fields: FieldSet,
}
pub struct FieldSet {
names: &'static [&'static str],
callsite: callsite::Identifier,
}
pub struct ValueSet<'a> {
values: &'a [(&'a Field, Option<&'a (dyn Value + 'a)>)],
fields: &'a FieldSet,
}
#[derive(Debug)]
pub struct Iter {
idxs: Range<usize>,
fields: FieldSet,
}
pub trait Visit {
fn record_i64(&mut self, field: &Field, value: i64) {
self.record_debug(field, &value)
}
fn record_u64(&mut self, field: &Field, value: u64) {
self.record_debug(field, &value)
}
fn record_bool(&mut self, field: &Field, value: bool) {
self.record_debug(field, &value)
}
fn record_str(&mut self, field: &Field, value: &str) {
self.record_debug(field, &value)
}
#[cfg(feature = "std")]
fn record_error(&mut self, field: &Field, value: &(dyn std::error::Error + 'static)) {
self.record_debug(field, &format_args!("{}", value))
}
fn record_debug(&mut self, field: &Field, value: &dyn fmt::Debug);
}
pub trait Value: crate::sealed::Sealed {
fn record(&self, key: &Field, visitor: &mut dyn Visit);
}
#[derive(Clone)]
pub struct DisplayValue<T: fmt::Display>(T);
#[derive(Clone)]
pub struct DebugValue<T: fmt::Debug>(T);
pub fn display<T>(t: T) -> DisplayValue<T>
where
T: fmt::Display,
{
DisplayValue(t)
}
pub fn debug<T>(t: T) -> DebugValue<T>
where
T: fmt::Debug,
{
DebugValue(t)
}
impl<'a, 'b> Visit for fmt::DebugStruct<'a, 'b> {
fn record_debug(&mut self, field: &Field, value: &dyn fmt::Debug) {
self.field(field.name(), value);
}
}
impl<'a, 'b> Visit for fmt::DebugMap<'a, 'b> {
fn record_debug(&mut self, field: &Field, value: &dyn fmt::Debug) {
self.entry(&format_args!("{}", field), value);
}
}
impl<F> Visit for F
where
F: FnMut(&Field, &dyn fmt::Debug),
{
fn record_debug(&mut self, field: &Field, value: &dyn fmt::Debug) {
(self)(field, value)
}
}
macro_rules! impl_values {
( $( $record:ident( $( $whatever:tt)+ ) ),+ ) => {
$(
impl_value!{ $record( $( $whatever )+ ) }
)+
}
}
macro_rules! impl_value {
( $record:ident( $( $value_ty:ty ),+ ) ) => {
$(
impl $crate::sealed::Sealed for $value_ty {}
impl $crate::field::Value for $value_ty {
fn record(
&self,
key: &$crate::field::Field,
visitor: &mut dyn $crate::field::Visit,
) {
visitor.$record(key, *self)
}
}
)+
};
( $record:ident( $( $value_ty:ty ),+ as $as_ty:ty) ) => {
$(
impl $crate::sealed::Sealed for $value_ty {}
impl Value for $value_ty {
fn record(
&self,
key: &$crate::field::Field,
visitor: &mut dyn $crate::field::Visit,
) {
visitor.$record(key, *self as $as_ty)
}
}
)+
};
}
impl_values! {
record_u64(u64),
record_u64(usize, u32, u16, u8 as u64),
record_i64(i64),
record_i64(isize, i32, i16, i8 as i64),
record_bool(bool)
}
impl crate::sealed::Sealed for str {}
impl Value for str {
fn record(&self, key: &Field, visitor: &mut dyn Visit) {
visitor.record_str(key, &self)
}
}
#[cfg(feature = "std")]
impl crate::sealed::Sealed for dyn std::error::Error + 'static {}
#[cfg(feature = "std")]
impl Value for dyn std::error::Error + 'static {
fn record(&self, key: &Field, visitor: &mut dyn Visit) {
visitor.record_error(key, self)
}
}
impl<'a, T: ?Sized> crate::sealed::Sealed for &'a T where T: Value + crate::sealed::Sealed + 'a {}
impl<'a, T: ?Sized> Value for &'a T
where
T: Value + 'a,
{
fn record(&self, key: &Field, visitor: &mut dyn Visit) {
(*self).record(key, visitor)
}
}
impl<'a> crate::sealed::Sealed for fmt::Arguments<'a> {}
impl<'a> Value for fmt::Arguments<'a> {
fn record(&self, key: &Field, visitor: &mut dyn Visit) {
visitor.record_debug(key, self)
}
}
impl<T: fmt::Display> crate::sealed::Sealed for DisplayValue<T> {}
impl<T> Value for DisplayValue<T>
where
T: fmt::Display,
{
fn record(&self, key: &Field, visitor: &mut dyn Visit) {
visitor.record_debug(key, &format_args!("{}", self.0))
}
}
impl<T: fmt::Display> fmt::Debug for DisplayValue<T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "{}", self.0)
}
}
impl<T: fmt::Debug> crate::sealed::Sealed for DebugValue<T> {}
impl<T: fmt::Debug> Value for DebugValue<T>
where
T: fmt::Debug,
{
fn record(&self, key: &Field, visitor: &mut dyn Visit) {
visitor.record_debug(key, &self.0)
}
}
impl<T: fmt::Debug> fmt::Debug for DebugValue<T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "{:?}", self.0)
}
}
impl Field {
#[inline]
pub fn callsite(&self) -> callsite::Identifier {
self.fields.callsite()
}
pub fn name(&self) -> &'static str {
self.fields.names[self.i]
}
}
impl fmt::Display for Field {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.pad(self.name())
}
}
impl AsRef<str> for Field {
fn as_ref(&self) -> &str {
self.name()
}
}
impl PartialEq for Field {
fn eq(&self, other: &Self) -> bool {
self.callsite() == other.callsite() && self.i == other.i
}
}
impl Eq for Field {}
impl Hash for Field {
fn hash<H>(&self, state: &mut H)
where
H: Hasher,
{
self.callsite().hash(state);
self.i.hash(state);
}
}
impl Clone for Field {
fn clone(&self) -> Self {
Field {
i: self.i,
fields: FieldSet {
names: self.fields.names,
callsite: self.fields.callsite(),
},
}
}
}
impl FieldSet {
pub const fn new(names: &'static [&'static str], callsite: callsite::Identifier) -> Self {
Self { names, callsite }
}
pub(crate) fn callsite(&self) -> callsite::Identifier {
callsite::Identifier(self.callsite.0)
}
pub fn field<Q: ?Sized>(&self, name: &Q) -> Option<Field>
where
Q: Borrow<str>,
{
let name = &name.borrow();
self.names.iter().position(|f| f == name).map(|i| Field {
i,
fields: FieldSet {
names: self.names,
callsite: self.callsite(),
},
})
}
pub fn contains(&self, field: &Field) -> bool {
field.callsite() == self.callsite() && field.i <= self.len()
}
pub fn iter(&self) -> Iter {
let idxs = 0..self.len();
Iter {
idxs,
fields: FieldSet {
names: self.names,
callsite: self.callsite(),
},
}
}
#[doc(hidden)]
pub fn value_set<'v, V>(&'v self, values: &'v V) -> ValueSet<'v>
where
V: ValidLen<'v>,
{
ValueSet {
fields: self,
values: &values.borrow()[..],
}
}
#[inline]
pub fn len(&self) -> usize {
self.names.len()
}
#[inline]
pub fn is_empty(&self) -> bool {
self.names.is_empty()
}
}
impl<'a> IntoIterator for &'a FieldSet {
type IntoIter = Iter;
type Item = Field;
#[inline]
fn into_iter(self) -> Self::IntoIter {
self.iter()
}
}
impl fmt::Debug for FieldSet {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("FieldSet")
.field("names", &self.names)
.field("callsite", &self.callsite)
.finish()
}
}
impl fmt::Display for FieldSet {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_set()
.entries(self.names.iter().map(display))
.finish()
}
}
impl Iterator for Iter {
type Item = Field;
fn next(&mut self) -> Option<Field> {
let i = self.idxs.next()?;
Some(Field {
i,
fields: FieldSet {
names: self.fields.names,
callsite: self.fields.callsite(),
},
})
}
}
impl<'a> ValueSet<'a> {
#[inline]
pub fn callsite(&self) -> callsite::Identifier {
self.fields.callsite()
}
pub(crate) fn record(&self, visitor: &mut dyn Visit) {
let my_callsite = self.callsite();
for (field, value) in self.values {
if field.callsite() != my_callsite {
continue;
}
if let Some(value) = value {
value.record(field, visitor);
}
}
}
pub(crate) fn contains(&self, field: &Field) -> bool {
field.callsite() == self.callsite()
&& self
.values
.iter()
.any(|(key, val)| *key == field && val.is_some())
}
pub(crate) fn is_empty(&self) -> bool {
let my_callsite = self.callsite();
self.values
.iter()
.all(|(key, val)| val.is_none() || key.callsite() != my_callsite)
}
pub(crate) fn field_set(&self) -> &FieldSet {
self.fields
}
}
impl<'a> fmt::Debug for ValueSet<'a> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
self.values
.iter()
.fold(&mut f.debug_struct("ValueSet"), |dbg, (key, v)| {
if let Some(val) = v {
val.record(key, dbg);
}
dbg
})
.field("callsite", &self.callsite())
.finish()
}
}
impl<'a> fmt::Display for ValueSet<'a> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
self.values
.iter()
.fold(&mut f.debug_map(), |dbg, (key, v)| {
if let Some(val) = v {
val.record(key, dbg);
}
dbg
})
.finish()
}
}
mod private {
use super::*;
pub trait ValidLen<'a>: Borrow<[(&'a Field, Option<&'a (dyn Value + 'a)>)]> {}
}
macro_rules! impl_valid_len {
( $( $len:tt ),+ ) => {
$(
impl<'a> private::ValidLen<'a> for
[(&'a Field, Option<&'a (dyn Value + 'a)>); $len] {}
)+
}
}
impl_valid_len! {
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,
21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32
}
#[cfg(test)]
mod test {
use super::*;
use crate::metadata::{Kind, Level, Metadata};
use crate::stdlib::{borrow::ToOwned, string::String};
struct TestCallsite1;
static TEST_CALLSITE_1: TestCallsite1 = TestCallsite1;
static TEST_META_1: Metadata<'static> = metadata! {
name: "field_test1",
target: module_path!(),
level: Level::INFO,
fields: &["foo", "bar", "baz"],
callsite: &TEST_CALLSITE_1,
kind: Kind::SPAN,
};
impl crate::callsite::Callsite for TestCallsite1 {
fn set_interest(&self, _: crate::subscriber::Interest) {
unimplemented!()
}
fn metadata(&self) -> &Metadata<'_> {
&TEST_META_1
}
}
struct TestCallsite2;
static TEST_CALLSITE_2: TestCallsite2 = TestCallsite2;
static TEST_META_2: Metadata<'static> = metadata! {
name: "field_test2",
target: module_path!(),
level: Level::INFO,
fields: &["foo", "bar", "baz"],
callsite: &TEST_CALLSITE_2,
kind: Kind::SPAN,
};
impl crate::callsite::Callsite for TestCallsite2 {
fn set_interest(&self, _: crate::subscriber::Interest) {
unimplemented!()
}
fn metadata(&self) -> &Metadata<'_> {
&TEST_META_2
}
}
#[test]
fn value_set_with_no_values_is_empty() {
let fields = TEST_META_1.fields();
let values = &[
(&fields.field("foo").unwrap(), None),
(&fields.field("bar").unwrap(), None),
(&fields.field("baz").unwrap(), None),
];
let valueset = fields.value_set(values);
assert!(valueset.is_empty());
}
#[test]
fn empty_value_set_is_empty() {
let fields = TEST_META_1.fields();
let valueset = fields.value_set(&[]);
assert!(valueset.is_empty());
}
#[test]
fn value_sets_with_fields_from_other_callsites_are_empty() {
let fields = TEST_META_1.fields();
let values = &[
(&fields.field("foo").unwrap(), Some(&1 as &dyn Value)),
(&fields.field("bar").unwrap(), Some(&2 as &dyn Value)),
(&fields.field("baz").unwrap(), Some(&3 as &dyn Value)),
];
let valueset = TEST_META_2.fields().value_set(values);
assert!(valueset.is_empty())
}
#[test]
fn sparse_value_sets_are_not_empty() {
let fields = TEST_META_1.fields();
let values = &[
(&fields.field("foo").unwrap(), None),
(&fields.field("bar").unwrap(), Some(&57 as &dyn Value)),
(&fields.field("baz").unwrap(), None),
];
let valueset = fields.value_set(values);
assert!(!valueset.is_empty());
}
#[test]
fn fields_from_other_callsets_are_skipped() {
let fields = TEST_META_1.fields();
let values = &[
(&fields.field("foo").unwrap(), None),
(
&TEST_META_2.fields().field("bar").unwrap(),
Some(&57 as &dyn Value),
),
(&fields.field("baz").unwrap(), None),
];
struct MyVisitor;
impl Visit for MyVisitor {
fn record_debug(&mut self, field: &Field, _: &dyn (crate::stdlib::fmt::Debug)) {
assert_eq!(field.callsite(), TEST_META_1.callsite())
}
}
let valueset = fields.value_set(values);
valueset.record(&mut MyVisitor);
}
#[test]
fn record_debug_fn() {
let fields = TEST_META_1.fields();
let values = &[
(&fields.field("foo").unwrap(), Some(&1 as &dyn Value)),
(&fields.field("bar").unwrap(), Some(&2 as &dyn Value)),
(&fields.field("baz").unwrap(), Some(&3 as &dyn Value)),
];
let valueset = fields.value_set(values);
let mut result = String::new();
valueset.record(&mut |_: &Field, value: &dyn fmt::Debug| {
use crate::stdlib::fmt::Write;
write!(&mut result, "{:?}", value).unwrap();
});
assert_eq!(result, "123".to_owned());
}
}