util: add default_value_vec for defaults without LengthReadable#4507

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Merged
TheBlueMatt merged 1 commit into from
Apr 1, 2026
Merged

util: add default_value_vec for defaults without LengthReadable #4507

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86 changes: 85 additions & 1 deletion lightning/src/util/ser_macros.rs
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Original file line numberDiff line numberDiff line change
Expand Up@@ -21,6 +21,9 @@ macro_rules! _encode_tlv {
($stream: expr, $type: expr, $field: expr, (default_value, $default: expr) $(, $self: ident)?) => {
$crate::_encode_tlv!($stream, $type, $field, required)
};
($stream: expr, $type: expr, $field: expr, (default_value_vec, $default: expr) $(, $self: ident)?) => {
$crate::_encode_tlv!($stream, $type, $field, required_vec)
};
($stream: expr, $type: expr, $field: expr, (static_value, $value: expr) $(, $self: ident)?) => {
let _ = &$field; // Ensure we "use" the $field
};
Expand DownExpand Up@@ -200,6 +203,9 @@ macro_rules! _get_varint_length_prefixed_tlv_length {
($len: expr, $type: expr, $field: expr, (default_value, $default: expr) $(, $self: ident)?) => {
$crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required)
};
($len: expr, $type: expr, $field: expr, (default_value_vec, $default: expr) $(, $self: ident)?) => {
$crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required_vec)
};
($len: expr, $type: expr, $field: expr, (static_value, $value: expr) $(, $self: ident)?) => {};
($len: expr, $type: expr, $field: expr, required $(, $self: ident)?) => {
BigSize($type).write(&mut $len).expect("No in-memory data may fail to serialize");
Expand DownExpand Up@@ -301,6 +307,15 @@ macro_rules! _check_decoded_tlv_order {
$field = $default.into();
}
}};
($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (default_value_vec, $default: expr)) => {{
$crate::_check_decoded_tlv_order!(
$last_seen_type,
$typ,
$type,
$field,
(default_value, $default)
);
}};
($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (static_value, $value: expr)) => {};
($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, required) => {{
// Note that $type may be 0 making the second comparison always false
Expand DownExpand Up@@ -372,6 +387,9 @@ macro_rules! _check_missing_tlv {
$field = $default.into();
}
}};
($last_seen_type: expr, $type: expr, $field: ident, (default_value_vec, $default: expr)) => {{
$crate::_check_missing_tlv!($last_seen_type, $type, $field, (default_value, $default));
}};
($last_seen_type: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
$field = $value;
};
Expand DownExpand Up@@ -440,6 +458,10 @@ macro_rules! _decode_tlv {
($outer_reader: expr, $reader: expr, $field: ident, (default_value, $default: expr)) => {{
$crate::_decode_tlv!($outer_reader, $reader, $field, required)
}};
($outer_reader: expr, $reader: expr, $field: ident, (default_value_vec, $default: expr)) => {{
let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::LengthReadable::read_from_fixed_length_buffer(&mut $reader)?;
$field = $crate::util::ser::RequiredWrapper(Some(f.0));
}};
($outer_reader: expr, $reader: expr, $field: ident, (static_value, $value: expr)) => {{
}};
($outer_reader: expr, $reader: expr, $field: ident, required) => {{
Expand DownExpand Up@@ -854,6 +876,9 @@ macro_rules! _init_tlv_based_struct_field {
($field: ident, (default_value, $default: expr)) => {
$field.0.unwrap()
};
($field: ident, (default_value_vec, $default: expr)) => {
$crate::_init_tlv_based_struct_field!($field, (default_value, $default))
};
($field: ident, (static_value, $value: expr)) => {
$field
};
Expand DownExpand Up@@ -905,6 +930,9 @@ macro_rules! _init_tlv_field_var {
($field: ident, (default_value, $default: expr)) => {
let mut $field = $crate::util::ser::RequiredWrapper(None);
};
($field: ident, (default_value_vec, $default: expr)) => {
$crate::_init_tlv_field_var!($field, (default_value, $default));
};
($field: ident, (static_value, $value: expr)) => {
let $field;
};
Expand DownExpand Up@@ -1007,6 +1035,9 @@ macro_rules! _decode_and_build {
///
/// If `$fieldty` is `required`, then `$field` is a required field that is not an [`Option`] nor a [`Vec`].
/// If `$fieldty` is `(default_value, $default)`, then `$field` will be set to `$default` if not present.
/// If `$fieldty` is `(default_value_vec, $default)`, then `$field` is a [`Vec`] which will be set to `$default`
/// if not present. Elements are serialized individually without a count prefix (like `required_vec`).
/// The TLV is always written, even if the vec is empty (matching `default_value` behavior).
/// If `$fieldty` is `(static_value, $static)`, then `$field` will be set to `$static`.
/// If `$fieldty` is `option`, then `$field` is optional field.
/// If `$fieldty` is `upgradable_option`, then `$field` is optional and read via [`MaybeReadable`].
Expand All@@ -1019,7 +1050,7 @@ macro_rules! _decode_and_build {
/// `Some`. When reading, an optional field of type `$ty` is read, and after all TLV fields are
/// read, the `$read` closure is called with the `Option<&$ty>` value. The `$read` closure should
/// return a `Result<(), DecodeError>`. Legacy field values can be used in later
/// `default_value` or `static_value` fields by referring to the value by name.
/// `default_value`, `default_value_vec`, or `static_value` fields by referring to the value by name.
/// If `$fieldty` is `(custom, $ty, $read, $write)` then, when writing, the same behavior as
/// `legacy`, above is used. When reading, if a TLV is present, it is read as `$ty` and the
/// `$read` method is called with `Some(decoded_$ty_object)`. If no TLV is present, the field
Expand DownExpand Up@@ -1956,6 +1987,59 @@ mod tests {
assert_eq!(read, ExpandedField { new_field: (42, 0) });
}

#[derive(Debug, PartialEq, Eq)]
struct DefaultValueVecStruct {
items: Vec<u32>,
}
impl_writeable_tlv_based!(DefaultValueVecStruct, {
(1, items, (default_value_vec, vec![4, 5, 6])),
});

#[test]
fn test_default_value_vec() {
// Non-empty vec round-trips correctly.
let instance = DefaultValueVecStruct { items: vec![1, 2, 3] };
let encoded = instance.encode();
let decoded: DefaultValueVecStruct = Readable::read(&mut &encoded[..]).unwrap();
assert_eq!(decoded, instance);

// Empty TLV stream falls back to the default.
let empty_encoded = <Vec<u8>>::from_hex("00").unwrap(); // zero-length TLV stream
let decoded: DefaultValueVecStruct = Readable::read(&mut &empty_encoded[..]).unwrap();
assert_eq!(decoded, DefaultValueVecStruct { items: vec![4, 5, 6] });

// Empty vec round-trips to empty vec (TLV is always written).
let empty_vec = DefaultValueVecStruct { items: vec![] };
let encoded = empty_vec.encode();
let decoded: DefaultValueVecStruct = Readable::read(&mut &encoded[..]).unwrap();
assert_eq!(decoded, DefaultValueVecStruct { items: vec![] });
}

#[derive(Debug, PartialEq, Eq)]
struct LegacyToVecStruct {
new_items: Vec<u32>,
}
impl_writeable_tlv_based!(LegacyToVecStruct, {
(0, old_item, (legacy, u32, |_| Ok(()),
|us: &LegacyToVecStruct| us.new_items.first().copied())),
(1, new_items, (default_value_vec,
old_item.map(|v| vec![v]).unwrap_or_default())),
});

#[test]
fn test_default_value_vec_with_legacy_fallback() {
// New format: round-trips via the new TLV.
let instance = LegacyToVecStruct { new_items: vec![10, 20, 30] };
let encoded = instance.encode();
let decoded: LegacyToVecStruct = Readable::read(&mut &encoded[..]).unwrap();
assert_eq!(decoded, instance);

// Old format: only the legacy type-0 field is present, falls back via default expression.
let old_encoded = <Vec<u8>>::from_hex("0600040000002a").unwrap(); // TLV len 6, type 0, len 4, value 42u32
Comment on lines +2037 to +2038

@jkczyzjkczyzMar 31, 2026

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nit: can make another struct for this.

let decoded: LegacyToVecStruct = Readable::read(&mut &old_encoded[..]).unwrap();
assert_eq!(decoded, LegacyToVecStruct { new_items: vec![42] });
}

#[test]
fn required_vec_with_encoding() {
// Ensure that serializing a required vec with a specified encoding will survive a ser round
Expand Down
Loading
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
 blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

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util: add default_value_vec for defaults without LengthReadable#4507

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 Merged

TheBlueMatt
merged 1 commit into

from

Apr 1, 2026
 Merged


util: add default_value_vec for defaults without LengthReadable
#4507
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86 changes: 85 additions & 1 deletion
lightning/src/util/ser_macros.rs

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -21,6 +21,9 @@ macro_rules! _encode_tlv {
	($stream: expr, $type: expr, $field: expr, (default_value, $default: expr) $(, $self: ident)?) => {
 $crate::_encode_tlv!($stream, $type, $field, required)
	};
	($stream: expr, $type: expr, $field: expr, (default_value_vec, $default: expr) $(, $self: ident)?) => {
 $crate::_encode_tlv!($stream, $type, $field, required_vec)
	};
	($stream: expr, $type: expr, $field: expr, (static_value, $value: expr) $(, $self: ident)?) => {
 let _ = &$field; // Ensure we "use" the $field
	};
Expand DownExpand Up@@ -200,6 +203,9 @@ macro_rules! _get_varint_length_prefixed_tlv_length {
	($len: expr, $type: expr, $field: expr, (default_value, $default: expr) $(, $self: ident)?) => {
 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required)
	};
	($len: expr, $type: expr, $field: expr, (default_value_vec, $default: expr) $(, $self: ident)?) => {
 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required_vec)
	};
	($len: expr, $type: expr, $field: expr, (static_value, $value: expr) $(, $self: ident)?) => {};
	($len: expr, $type: expr, $field: expr, required $(, $self: ident)?) => {
 BigSize($type).write(&mut $len).expect("No in-memory data may fail to serialize");
Expand DownExpand Up@@ -301,6 +307,15 @@ macro_rules! _check_decoded_tlv_order {
 $field = $default.into();
 }
	}};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 $crate::_check_decoded_tlv_order!(
 $last_seen_type,
 $typ,
 $type,
 $field,
 (default_value, $default)
 );
	}};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (static_value, $value: expr)) => {};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, required) => {{
 // Note that $type may be 0 making the second comparison always false
Expand DownExpand Up@@ -372,6 +387,9 @@ macro_rules! _check_missing_tlv {
 $field = $default.into();
 }
	}};
	($last_seen_type: expr, $type: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 $crate::_check_missing_tlv!($last_seen_type, $type, $field, (default_value, $default));
	}};
	($last_seen_type: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
 $field = $value;
	};
Expand DownExpand Up@@ -440,6 +458,10 @@ macro_rules! _decode_tlv {
	($outer_reader: expr, $reader: expr, $field: ident, (default_value, $default: expr)) => {{
 $crate::_decode_tlv!($outer_reader, $reader, $field, required)
	}};
	($outer_reader: expr, $reader: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::LengthReadable::read_from_fixed_length_buffer(&mut $reader)?;
 $field = $crate::util::ser::RequiredWrapper(Some(f.0));
	}};
	($outer_reader: expr, $reader: expr, $field: ident, (static_value, $value: expr)) => {{
	}};
	($outer_reader: expr, $reader: expr, $field: ident, required) => {{
Expand DownExpand Up@@ -854,6 +876,9 @@ macro_rules! _init_tlv_based_struct_field {
	($field: ident, (default_value, $default: expr)) => {
 $field.0.unwrap()
	};
	($field: ident, (default_value_vec, $default: expr)) => {
 $crate::_init_tlv_based_struct_field!($field, (default_value, $default))
	};
	($field: ident, (static_value, $value: expr)) => {
 $field
	};
Expand DownExpand Up@@ -905,6 +930,9 @@ macro_rules! _init_tlv_field_var {
	($field: ident, (default_value, $default: expr)) => {
 let mut $field = $crate::util::ser::RequiredWrapper(None);
	};
	($field: ident, (default_value_vec, $default: expr)) => {
 $crate::_init_tlv_field_var!($field, (default_value, $default));
	};
	($field: ident, (static_value, $value: expr)) => {
 let $field;
	};
Expand DownExpand Up@@ -1007,6 +1035,9 @@ macro_rules! _decode_and_build {
///
/// If `$fieldty` is `required`, then `$field` is a required field that is not an [`Option`] nor a [`Vec`].
/// If `$fieldty` is `(default_value, $default)`, then `$field` will be set to `$default` if not present.
/// If `$fieldty` is `(default_value_vec, $default)`, then `$field` is a [`Vec`] which will be set to `$default`
/// if not present. Elements are serialized individually without a count prefix (like `required_vec`).
/// The TLV is always written, even if the vec is empty (matching `default_value` behavior).
/// If `$fieldty` is `(static_value, $static)`, then `$field` will be set to `$static`.
/// If `$fieldty` is `option`, then `$field` is optional field.
/// If `$fieldty` is `upgradable_option`, then `$field` is optional and read via [`MaybeReadable`].
Expand All@@ -1019,7 +1050,7 @@ macro_rules! _decode_and_build {
/// `Some`. When reading, an optional field of type `$ty` is read, and after all TLV fields are
/// read, the `$read` closure is called with the `Option<&$ty>` value. The `$read` closure should
/// return a `Result<(), DecodeError>`. Legacy field values can be used in later
/// `default_value` or `static_value` fields by referring to the value by name.
/// `default_value`, `default_value_vec`, or `static_value` fields by referring to the value by name.
/// If `$fieldty` is `(custom, $ty, $read, $write)` then, when writing, the same behavior as
/// `legacy`, above is used. When reading, if a TLV is present, it is read as `$ty` and the
/// `$read` method is called with `Some(decoded_$ty_object)`. If no TLV is present, the field
Expand DownExpand Up@@ -1956,6 +1987,59 @@ mod tests {
 assert_eq!(read, ExpandedField { new_field: (42, 0) });
	}

	#[derive(Debug, PartialEq, Eq)]
	struct DefaultValueVecStruct {
 items: Vec<u32>,
	}
	impl_writeable_tlv_based!(DefaultValueVecStruct, {
 (1, items, (default_value_vec, vec![4, 5, 6])),
	});

	#[test]
	fn test_default_value_vec() {
 // Non-empty vec round-trips correctly.
 let instance = DefaultValueVecStruct { items: vec![1, 2, 3] };
 let encoded = instance.encode();
 let decoded: DefaultValueVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, instance);

 // Empty TLV stream falls back to the default.
 let empty_encoded = <Vec<u8>>::from_hex("00").unwrap(); // zero-length TLV stream
 let decoded: DefaultValueVecStruct = Readable::read(&mut &empty_encoded[..]).unwrap();
 assert_eq!(decoded, DefaultValueVecStruct { items: vec![4, 5, 6] });

 // Empty vec round-trips to empty vec (TLV is always written).
 let empty_vec = DefaultValueVecStruct { items: vec![] };
 let encoded = empty_vec.encode();
 let decoded: DefaultValueVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, DefaultValueVecStruct { items: vec![] });
	}

	#[derive(Debug, PartialEq, Eq)]
	struct LegacyToVecStruct {
 new_items: Vec<u32>,
	}
	impl_writeable_tlv_based!(LegacyToVecStruct, {
 (0, old_item, (legacy, u32, |_| Ok(()),
 |us: &LegacyToVecStruct| us.new_items.first().copied())),
 (1, new_items, (default_value_vec,
 old_item.map(|v| vec![v]).unwrap_or_default())),
	});

	#[test]
	fn test_default_value_vec_with_legacy_fallback() {
 // New format: round-trips via the new TLV.
 let instance = LegacyToVecStruct { new_items: vec![10, 20, 30] };
 let encoded = instance.encode();
 let decoded: LegacyToVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, instance);

 // Old format: only the legacy type-0 field is present, falls back via default expression.
 let old_encoded = <Vec<u8>>::from_hex("0600040000002a").unwrap(); // TLV len 6, type 0, len 4, value 42u32

Comment on lines

+2037
 to 
+2038

@jkczyzjkczyzMar 31, 2026

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nit: can make another struct for this.
 let decoded: LegacyToVecStruct = Readable::read(&mut &old_encoded[..]).unwrap();
 assert_eq!(decoded, LegacyToVecStruct { new_items: vec![42] });
	}

	#[test]
	fn required_vec_with_encoding() {
 // Ensure that serializing a required vec with a specified encoding will survive a ser round
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
util: add default_value_vec for defaults without LengthReadable#4507

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 Merged

TheBlueMatt
merged 1 commit into

from

Apr 1, 2026
 Merged


util: add default_value_vec for defaults without LengthReadable
#4507
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86 changes: 85 additions & 1 deletion
lightning/src/util/ser_macros.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -21,6 +21,9 @@ macro_rules! _encode_tlv {
	($stream: expr, $type: expr, $field: expr, (default_value, $default: expr) $(, $self: ident)?) => {
 $crate::_encode_tlv!($stream, $type, $field, required)
	};
	($stream: expr, $type: expr, $field: expr, (default_value_vec, $default: expr) $(, $self: ident)?) => {
 $crate::_encode_tlv!($stream, $type, $field, required_vec)
	};
	($stream: expr, $type: expr, $field: expr, (static_value, $value: expr) $(, $self: ident)?) => {
 let _ = &$field; // Ensure we "use" the $field
	};
Expand DownExpand Up@@ -200,6 +203,9 @@ macro_rules! _get_varint_length_prefixed_tlv_length {
	($len: expr, $type: expr, $field: expr, (default_value, $default: expr) $(, $self: ident)?) => {
 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required)
	};
	($len: expr, $type: expr, $field: expr, (default_value_vec, $default: expr) $(, $self: ident)?) => {
 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required_vec)
	};
	($len: expr, $type: expr, $field: expr, (static_value, $value: expr) $(, $self: ident)?) => {};
	($len: expr, $type: expr, $field: expr, required $(, $self: ident)?) => {
 BigSize($type).write(&mut $len).expect("No in-memory data may fail to serialize");
Expand DownExpand Up@@ -301,6 +307,15 @@ macro_rules! _check_decoded_tlv_order {
 $field = $default.into();
 }
	}};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 $crate::_check_decoded_tlv_order!(
 $last_seen_type,
 $typ,
 $type,
 $field,
 (default_value, $default)
 );
	}};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (static_value, $value: expr)) => {};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, required) => {{
 // Note that $type may be 0 making the second comparison always false
Expand DownExpand Up@@ -372,6 +387,9 @@ macro_rules! _check_missing_tlv {
 $field = $default.into();
 }
	}};
	($last_seen_type: expr, $type: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 $crate::_check_missing_tlv!($last_seen_type, $type, $field, (default_value, $default));
	}};
	($last_seen_type: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
 $field = $value;
	};
Expand DownExpand Up@@ -440,6 +458,10 @@ macro_rules! _decode_tlv {
	($outer_reader: expr, $reader: expr, $field: ident, (default_value, $default: expr)) => {{
 $crate::_decode_tlv!($outer_reader, $reader, $field, required)
	}};
	($outer_reader: expr, $reader: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::LengthReadable::read_from_fixed_length_buffer(&mut $reader)?;
 $field = $crate::util::ser::RequiredWrapper(Some(f.0));
	}};
	($outer_reader: expr, $reader: expr, $field: ident, (static_value, $value: expr)) => {{
	}};
	($outer_reader: expr, $reader: expr, $field: ident, required) => {{
Expand DownExpand Up@@ -854,6 +876,9 @@ macro_rules! _init_tlv_based_struct_field {
	($field: ident, (default_value, $default: expr)) => {
 $field.0.unwrap()
	};
	($field: ident, (default_value_vec, $default: expr)) => {
 $crate::_init_tlv_based_struct_field!($field, (default_value, $default))
	};
	($field: ident, (static_value, $value: expr)) => {
 $field
	};
Expand DownExpand Up@@ -905,6 +930,9 @@ macro_rules! _init_tlv_field_var {
	($field: ident, (default_value, $default: expr)) => {
 let mut $field = $crate::util::ser::RequiredWrapper(None);
	};
	($field: ident, (default_value_vec, $default: expr)) => {
 $crate::_init_tlv_field_var!($field, (default_value, $default));
	};
	($field: ident, (static_value, $value: expr)) => {
 let $field;
	};
Expand DownExpand Up@@ -1007,6 +1035,9 @@ macro_rules! _decode_and_build {
///
/// If `$fieldty` is `required`, then `$field` is a required field that is not an [`Option`] nor a [`Vec`].
/// If `$fieldty` is `(default_value, $default)`, then `$field` will be set to `$default` if not present.
/// If `$fieldty` is `(default_value_vec, $default)`, then `$field` is a [`Vec`] which will be set to `$default`
/// if not present. Elements are serialized individually without a count prefix (like `required_vec`).
/// The TLV is always written, even if the vec is empty (matching `default_value` behavior).
/// If `$fieldty` is `(static_value, $static)`, then `$field` will be set to `$static`.
/// If `$fieldty` is `option`, then `$field` is optional field.
/// If `$fieldty` is `upgradable_option`, then `$field` is optional and read via [`MaybeReadable`].
Expand All@@ -1019,7 +1050,7 @@ macro_rules! _decode_and_build {
/// `Some`. When reading, an optional field of type `$ty` is read, and after all TLV fields are
/// read, the `$read` closure is called with the `Option<&$ty>` value. The `$read` closure should
/// return a `Result<(), DecodeError>`. Legacy field values can be used in later
/// `default_value` or `static_value` fields by referring to the value by name.
/// `default_value`, `default_value_vec`, or `static_value` fields by referring to the value by name.
/// If `$fieldty` is `(custom, $ty, $read, $write)` then, when writing, the same behavior as
/// `legacy`, above is used. When reading, if a TLV is present, it is read as `$ty` and the
/// `$read` method is called with `Some(decoded_$ty_object)`. If no TLV is present, the field
Expand DownExpand Up@@ -1956,6 +1987,59 @@ mod tests {
 assert_eq!(read, ExpandedField { new_field: (42, 0) });
	}

	#[derive(Debug, PartialEq, Eq)]
	struct DefaultValueVecStruct {
 items: Vec<u32>,
	}
	impl_writeable_tlv_based!(DefaultValueVecStruct, {
 (1, items, (default_value_vec, vec![4, 5, 6])),
	});

	#[test]
	fn test_default_value_vec() {
 // Non-empty vec round-trips correctly.
 let instance = DefaultValueVecStruct { items: vec![1, 2, 3] };
 let encoded = instance.encode();
 let decoded: DefaultValueVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, instance);

 // Empty TLV stream falls back to the default.
 let empty_encoded = <Vec<u8>>::from_hex("00").unwrap(); // zero-length TLV stream
 let decoded: DefaultValueVecStruct = Readable::read(&mut &empty_encoded[..]).unwrap();
 assert_eq!(decoded, DefaultValueVecStruct { items: vec![4, 5, 6] });

 // Empty vec round-trips to empty vec (TLV is always written).
 let empty_vec = DefaultValueVecStruct { items: vec![] };
 let encoded = empty_vec.encode();
 let decoded: DefaultValueVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, DefaultValueVecStruct { items: vec![] });
	}

	#[derive(Debug, PartialEq, Eq)]
	struct LegacyToVecStruct {
 new_items: Vec<u32>,
	}
	impl_writeable_tlv_based!(LegacyToVecStruct, {
 (0, old_item, (legacy, u32, |_| Ok(()),
 |us: &LegacyToVecStruct| us.new_items.first().copied())),
 (1, new_items, (default_value_vec,
 old_item.map(|v| vec![v]).unwrap_or_default())),
	});

	#[test]
	fn test_default_value_vec_with_legacy_fallback() {
 // New format: round-trips via the new TLV.
 let instance = LegacyToVecStruct { new_items: vec![10, 20, 30] };
 let encoded = instance.encode();
 let decoded: LegacyToVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, instance);

 // Old format: only the legacy type-0 field is present, falls back via default expression.
 let old_encoded = <Vec<u8>>::from_hex("0600040000002a").unwrap(); // TLV len 6, type 0, len 4, value 42u32

Comment on lines

+2037
 to 
+2038

@jkczyzjkczyzMar 31, 2026

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nit: can make another struct for this.
 let decoded: LegacyToVecStruct = Readable::read(&mut &old_encoded[..]).unwrap();
 assert_eq!(decoded, LegacyToVecStruct { new_items: vec![42] });
	}

	#[test]
	fn required_vec_with_encoding() {
 // Ensure that serializing a required vec with a specified encoding will survive a ser round
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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util: add default_value_vec for defaults without LengthReadable#4507

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TheBlueMatt
merged 1 commit into

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Apr 1, 2026
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util: add default_value_vec for defaults without LengthReadable
#4507
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86 changes: 85 additions & 1 deletion
lightning/src/util/ser_macros.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -21,6 +21,9 @@ macro_rules! _encode_tlv {
	($stream: expr, $type: expr, $field: expr, (default_value, $default: expr) $(, $self: ident)?) => {
 $crate::_encode_tlv!($stream, $type, $field, required)
	};
	($stream: expr, $type: expr, $field: expr, (default_value_vec, $default: expr) $(, $self: ident)?) => {
 $crate::_encode_tlv!($stream, $type, $field, required_vec)
	};
	($stream: expr, $type: expr, $field: expr, (static_value, $value: expr) $(, $self: ident)?) => {
 let _ = &$field; // Ensure we "use" the $field
	};
Expand DownExpand Up@@ -200,6 +203,9 @@ macro_rules! _get_varint_length_prefixed_tlv_length {
	($len: expr, $type: expr, $field: expr, (default_value, $default: expr) $(, $self: ident)?) => {
 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required)
	};
	($len: expr, $type: expr, $field: expr, (default_value_vec, $default: expr) $(, $self: ident)?) => {
 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required_vec)
	};
	($len: expr, $type: expr, $field: expr, (static_value, $value: expr) $(, $self: ident)?) => {};
	($len: expr, $type: expr, $field: expr, required $(, $self: ident)?) => {
 BigSize($type).write(&mut $len).expect("No in-memory data may fail to serialize");
Expand DownExpand Up@@ -301,6 +307,15 @@ macro_rules! _check_decoded_tlv_order {
 $field = $default.into();
 }
	}};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 $crate::_check_decoded_tlv_order!(
 $last_seen_type,
 $typ,
 $type,
 $field,
 (default_value, $default)
 );
	}};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (static_value, $value: expr)) => {};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, required) => {{
 // Note that $type may be 0 making the second comparison always false
Expand DownExpand Up@@ -372,6 +387,9 @@ macro_rules! _check_missing_tlv {
 $field = $default.into();
 }
	}};
	($last_seen_type: expr, $type: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 $crate::_check_missing_tlv!($last_seen_type, $type, $field, (default_value, $default));
	}};
	($last_seen_type: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
 $field = $value;
	};
Expand DownExpand Up@@ -440,6 +458,10 @@ macro_rules! _decode_tlv {
	($outer_reader: expr, $reader: expr, $field: ident, (default_value, $default: expr)) => {{
 $crate::_decode_tlv!($outer_reader, $reader, $field, required)
	}};
	($outer_reader: expr, $reader: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::LengthReadable::read_from_fixed_length_buffer(&mut $reader)?;
 $field = $crate::util::ser::RequiredWrapper(Some(f.0));
	}};
	($outer_reader: expr, $reader: expr, $field: ident, (static_value, $value: expr)) => {{
	}};
	($outer_reader: expr, $reader: expr, $field: ident, required) => {{
Expand DownExpand Up@@ -854,6 +876,9 @@ macro_rules! _init_tlv_based_struct_field {
	($field: ident, (default_value, $default: expr)) => {
 $field.0.unwrap()
	};
	($field: ident, (default_value_vec, $default: expr)) => {
 $crate::_init_tlv_based_struct_field!($field, (default_value, $default))
	};
	($field: ident, (static_value, $value: expr)) => {
 $field
	};
Expand DownExpand Up@@ -905,6 +930,9 @@ macro_rules! _init_tlv_field_var {
	($field: ident, (default_value, $default: expr)) => {
 let mut $field = $crate::util::ser::RequiredWrapper(None);
	};
	($field: ident, (default_value_vec, $default: expr)) => {
 $crate::_init_tlv_field_var!($field, (default_value, $default));
	};
	($field: ident, (static_value, $value: expr)) => {
 let $field;
	};
Expand DownExpand Up@@ -1007,6 +1035,9 @@ macro_rules! _decode_and_build {
///
/// If `$fieldty` is `required`, then `$field` is a required field that is not an [`Option`] nor a [`Vec`].
/// If `$fieldty` is `(default_value, $default)`, then `$field` will be set to `$default` if not present.
/// If `$fieldty` is `(default_value_vec, $default)`, then `$field` is a [`Vec`] which will be set to `$default`
/// if not present. Elements are serialized individually without a count prefix (like `required_vec`).
/// The TLV is always written, even if the vec is empty (matching `default_value` behavior).
/// If `$fieldty` is `(static_value, $static)`, then `$field` will be set to `$static`.
/// If `$fieldty` is `option`, then `$field` is optional field.
/// If `$fieldty` is `upgradable_option`, then `$field` is optional and read via [`MaybeReadable`].
Expand All@@ -1019,7 +1050,7 @@ macro_rules! _decode_and_build {
/// `Some`. When reading, an optional field of type `$ty` is read, and after all TLV fields are
/// read, the `$read` closure is called with the `Option<&$ty>` value. The `$read` closure should
/// return a `Result<(), DecodeError>`. Legacy field values can be used in later
/// `default_value` or `static_value` fields by referring to the value by name.
/// `default_value`, `default_value_vec`, or `static_value` fields by referring to the value by name.
/// If `$fieldty` is `(custom, $ty, $read, $write)` then, when writing, the same behavior as
/// `legacy`, above is used. When reading, if a TLV is present, it is read as `$ty` and the
/// `$read` method is called with `Some(decoded_$ty_object)`. If no TLV is present, the field
Expand DownExpand Up@@ -1956,6 +1987,59 @@ mod tests {
 assert_eq!(read, ExpandedField { new_field: (42, 0) });
	}

	#[derive(Debug, PartialEq, Eq)]
	struct DefaultValueVecStruct {
 items: Vec<u32>,
	}
	impl_writeable_tlv_based!(DefaultValueVecStruct, {
 (1, items, (default_value_vec, vec![4, 5, 6])),
	});

	#[test]
	fn test_default_value_vec() {
 // Non-empty vec round-trips correctly.
 let instance = DefaultValueVecStruct { items: vec![1, 2, 3] };
 let encoded = instance.encode();
 let decoded: DefaultValueVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, instance);

 // Empty TLV stream falls back to the default.
 let empty_encoded = <Vec<u8>>::from_hex("00").unwrap(); // zero-length TLV stream
 let decoded: DefaultValueVecStruct = Readable::read(&mut &empty_encoded[..]).unwrap();
 assert_eq!(decoded, DefaultValueVecStruct { items: vec![4, 5, 6] });

 // Empty vec round-trips to empty vec (TLV is always written).
 let empty_vec = DefaultValueVecStruct { items: vec![] };
 let encoded = empty_vec.encode();
 let decoded: DefaultValueVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, DefaultValueVecStruct { items: vec![] });
	}

	#[derive(Debug, PartialEq, Eq)]
	struct LegacyToVecStruct {
 new_items: Vec<u32>,
	}
	impl_writeable_tlv_based!(LegacyToVecStruct, {
 (0, old_item, (legacy, u32, |_| Ok(()),
 |us: &LegacyToVecStruct| us.new_items.first().copied())),
 (1, new_items, (default_value_vec,
 old_item.map(|v| vec![v]).unwrap_or_default())),
	});

	#[test]
	fn test_default_value_vec_with_legacy_fallback() {
 // New format: round-trips via the new TLV.
 let instance = LegacyToVecStruct { new_items: vec![10, 20, 30] };
 let encoded = instance.encode();
 let decoded: LegacyToVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, instance);

 // Old format: only the legacy type-0 field is present, falls back via default expression.
 let old_encoded = <Vec<u8>>::from_hex("0600040000002a").unwrap(); // TLV len 6, type 0, len 4, value 42u32

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+2038

@jkczyzjkczyzMar 31, 2026

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nit: can make another struct for this.
 let decoded: LegacyToVecStruct = Readable::read(&mut &old_encoded[..]).unwrap();
 assert_eq!(decoded, LegacyToVecStruct { new_items: vec![42] });
	}

	#[test]
	fn required_vec_with_encoding() {
 // Ensure that serializing a required vec with a specified encoding will survive a ser round
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

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util: add default_value_vec for defaults without LengthReadable#4507

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 Merged

TheBlueMatt
merged 1 commit into

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Apr 1, 2026
 Merged


util: add default_value_vec for defaults without LengthReadable
#4507
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86 changes: 85 additions & 1 deletion
lightning/src/util/ser_macros.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -21,6 +21,9 @@ macro_rules! _encode_tlv {
	($stream: expr, $type: expr, $field: expr, (default_value, $default: expr) $(, $self: ident)?) => {
 $crate::_encode_tlv!($stream, $type, $field, required)
	};
	($stream: expr, $type: expr, $field: expr, (default_value_vec, $default: expr) $(, $self: ident)?) => {
 $crate::_encode_tlv!($stream, $type, $field, required_vec)
	};
	($stream: expr, $type: expr, $field: expr, (static_value, $value: expr) $(, $self: ident)?) => {
 let _ = &$field; // Ensure we "use" the $field
	};
Expand DownExpand Up@@ -200,6 +203,9 @@ macro_rules! _get_varint_length_prefixed_tlv_length {
	($len: expr, $type: expr, $field: expr, (default_value, $default: expr) $(, $self: ident)?) => {
 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required)
	};
	($len: expr, $type: expr, $field: expr, (default_value_vec, $default: expr) $(, $self: ident)?) => {
 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required_vec)
	};
	($len: expr, $type: expr, $field: expr, (static_value, $value: expr) $(, $self: ident)?) => {};
	($len: expr, $type: expr, $field: expr, required $(, $self: ident)?) => {
 BigSize($type).write(&mut $len).expect("No in-memory data may fail to serialize");
Expand DownExpand Up@@ -301,6 +307,15 @@ macro_rules! _check_decoded_tlv_order {
 $field = $default.into();
 }
	}};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 $crate::_check_decoded_tlv_order!(
 $last_seen_type,
 $typ,
 $type,
 $field,
 (default_value, $default)
 );
	}};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (static_value, $value: expr)) => {};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, required) => {{
 // Note that $type may be 0 making the second comparison always false
Expand DownExpand Up@@ -372,6 +387,9 @@ macro_rules! _check_missing_tlv {
 $field = $default.into();
 }
	}};
	($last_seen_type: expr, $type: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 $crate::_check_missing_tlv!($last_seen_type, $type, $field, (default_value, $default));
	}};
	($last_seen_type: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
 $field = $value;
	};
Expand DownExpand Up@@ -440,6 +458,10 @@ macro_rules! _decode_tlv {
	($outer_reader: expr, $reader: expr, $field: ident, (default_value, $default: expr)) => {{
 $crate::_decode_tlv!($outer_reader, $reader, $field, required)
	}};
	($outer_reader: expr, $reader: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::LengthReadable::read_from_fixed_length_buffer(&mut $reader)?;
 $field = $crate::util::ser::RequiredWrapper(Some(f.0));
	}};
	($outer_reader: expr, $reader: expr, $field: ident, (static_value, $value: expr)) => {{
	}};
	($outer_reader: expr, $reader: expr, $field: ident, required) => {{
Expand DownExpand Up@@ -854,6 +876,9 @@ macro_rules! _init_tlv_based_struct_field {
	($field: ident, (default_value, $default: expr)) => {
 $field.0.unwrap()
	};
	($field: ident, (default_value_vec, $default: expr)) => {
 $crate::_init_tlv_based_struct_field!($field, (default_value, $default))
	};
	($field: ident, (static_value, $value: expr)) => {
 $field
	};
Expand DownExpand Up@@ -905,6 +930,9 @@ macro_rules! _init_tlv_field_var {
	($field: ident, (default_value, $default: expr)) => {
 let mut $field = $crate::util::ser::RequiredWrapper(None);
	};
	($field: ident, (default_value_vec, $default: expr)) => {
 $crate::_init_tlv_field_var!($field, (default_value, $default));
	};
	($field: ident, (static_value, $value: expr)) => {
 let $field;
	};
Expand DownExpand Up@@ -1007,6 +1035,9 @@ macro_rules! _decode_and_build {
///
/// If `$fieldty` is `required`, then `$field` is a required field that is not an [`Option`] nor a [`Vec`].
/// If `$fieldty` is `(default_value, $default)`, then `$field` will be set to `$default` if not present.
/// If `$fieldty` is `(default_value_vec, $default)`, then `$field` is a [`Vec`] which will be set to `$default`
/// if not present. Elements are serialized individually without a count prefix (like `required_vec`).
/// The TLV is always written, even if the vec is empty (matching `default_value` behavior).
/// If `$fieldty` is `(static_value, $static)`, then `$field` will be set to `$static`.
/// If `$fieldty` is `option`, then `$field` is optional field.
/// If `$fieldty` is `upgradable_option`, then `$field` is optional and read via [`MaybeReadable`].
Expand All@@ -1019,7 +1050,7 @@ macro_rules! _decode_and_build {
/// `Some`. When reading, an optional field of type `$ty` is read, and after all TLV fields are
/// read, the `$read` closure is called with the `Option<&$ty>` value. The `$read` closure should
/// return a `Result<(), DecodeError>`. Legacy field values can be used in later
/// `default_value` or `static_value` fields by referring to the value by name.
/// `default_value`, `default_value_vec`, or `static_value` fields by referring to the value by name.
/// If `$fieldty` is `(custom, $ty, $read, $write)` then, when writing, the same behavior as
/// `legacy`, above is used. When reading, if a TLV is present, it is read as `$ty` and the
/// `$read` method is called with `Some(decoded_$ty_object)`. If no TLV is present, the field
Expand DownExpand Up@@ -1956,6 +1987,59 @@ mod tests {
 assert_eq!(read, ExpandedField { new_field: (42, 0) });
	}

	#[derive(Debug, PartialEq, Eq)]
	struct DefaultValueVecStruct {
 items: Vec<u32>,
	}
	impl_writeable_tlv_based!(DefaultValueVecStruct, {
 (1, items, (default_value_vec, vec![4, 5, 6])),
	});

	#[test]
	fn test_default_value_vec() {
 // Non-empty vec round-trips correctly.
 let instance = DefaultValueVecStruct { items: vec![1, 2, 3] };
 let encoded = instance.encode();
 let decoded: DefaultValueVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, instance);

 // Empty TLV stream falls back to the default.
 let empty_encoded = <Vec<u8>>::from_hex("00").unwrap(); // zero-length TLV stream
 let decoded: DefaultValueVecStruct = Readable::read(&mut &empty_encoded[..]).unwrap();
 assert_eq!(decoded, DefaultValueVecStruct { items: vec![4, 5, 6] });

 // Empty vec round-trips to empty vec (TLV is always written).
 let empty_vec = DefaultValueVecStruct { items: vec![] };
 let encoded = empty_vec.encode();
 let decoded: DefaultValueVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, DefaultValueVecStruct { items: vec![] });
	}

	#[derive(Debug, PartialEq, Eq)]
	struct LegacyToVecStruct {
 new_items: Vec<u32>,
	}
	impl_writeable_tlv_based!(LegacyToVecStruct, {
 (0, old_item, (legacy, u32, |_| Ok(()),
 |us: &LegacyToVecStruct| us.new_items.first().copied())),
 (1, new_items, (default_value_vec,
 old_item.map(|v| vec![v]).unwrap_or_default())),
	});

	#[test]
	fn test_default_value_vec_with_legacy_fallback() {
 // New format: round-trips via the new TLV.
 let instance = LegacyToVecStruct { new_items: vec![10, 20, 30] };
 let encoded = instance.encode();
 let decoded: LegacyToVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, instance);

 // Old format: only the legacy type-0 field is present, falls back via default expression.
 let old_encoded = <Vec<u8>>::from_hex("0600040000002a").unwrap(); // TLV len 6, type 0, len 4, value 42u32

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+2038

@jkczyzjkczyzMar 31, 2026

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nit: can make another struct for this.
 let decoded: LegacyToVecStruct = Readable::read(&mut &old_encoded[..]).unwrap();
 assert_eq!(decoded, LegacyToVecStruct { new_items: vec![42] });
	}

	#[test]
	fn required_vec_with_encoding() {
 // Ensure that serializing a required vec with a specified encoding will survive a ser round
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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util: add default_value_vec for defaults without LengthReadable#4507

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util: add default_value_vec for defaults without LengthReadable
#4507
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86 changes: 85 additions & 1 deletion
lightning/src/util/ser_macros.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -21,6 +21,9 @@ macro_rules! _encode_tlv {
	($stream: expr, $type: expr, $field: expr, (default_value, $default: expr) $(, $self: ident)?) => {
 $crate::_encode_tlv!($stream, $type, $field, required)
	};
	($stream: expr, $type: expr, $field: expr, (default_value_vec, $default: expr) $(, $self: ident)?) => {
 $crate::_encode_tlv!($stream, $type, $field, required_vec)
	};
	($stream: expr, $type: expr, $field: expr, (static_value, $value: expr) $(, $self: ident)?) => {
 let _ = &$field; // Ensure we "use" the $field
	};
Expand DownExpand Up@@ -200,6 +203,9 @@ macro_rules! _get_varint_length_prefixed_tlv_length {
	($len: expr, $type: expr, $field: expr, (default_value, $default: expr) $(, $self: ident)?) => {
 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required)
	};
	($len: expr, $type: expr, $field: expr, (default_value_vec, $default: expr) $(, $self: ident)?) => {
 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required_vec)
	};
	($len: expr, $type: expr, $field: expr, (static_value, $value: expr) $(, $self: ident)?) => {};
	($len: expr, $type: expr, $field: expr, required $(, $self: ident)?) => {
 BigSize($type).write(&mut $len).expect("No in-memory data may fail to serialize");
Expand DownExpand Up@@ -301,6 +307,15 @@ macro_rules! _check_decoded_tlv_order {
 $field = $default.into();
 }
	}};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 $crate::_check_decoded_tlv_order!(
 $last_seen_type,
 $typ,
 $type,
 $field,
 (default_value, $default)
 );
	}};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (static_value, $value: expr)) => {};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, required) => {{
 // Note that $type may be 0 making the second comparison always false
Expand DownExpand Up@@ -372,6 +387,9 @@ macro_rules! _check_missing_tlv {
 $field = $default.into();
 }
	}};
	($last_seen_type: expr, $type: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 $crate::_check_missing_tlv!($last_seen_type, $type, $field, (default_value, $default));
	}};
	($last_seen_type: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
 $field = $value;
	};
Expand DownExpand Up@@ -440,6 +458,10 @@ macro_rules! _decode_tlv {
	($outer_reader: expr, $reader: expr, $field: ident, (default_value, $default: expr)) => {{
 $crate::_decode_tlv!($outer_reader, $reader, $field, required)
	}};
	($outer_reader: expr, $reader: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::LengthReadable::read_from_fixed_length_buffer(&mut $reader)?;
 $field = $crate::util::ser::RequiredWrapper(Some(f.0));
	}};
	($outer_reader: expr, $reader: expr, $field: ident, (static_value, $value: expr)) => {{
	}};
	($outer_reader: expr, $reader: expr, $field: ident, required) => {{
Expand DownExpand Up@@ -854,6 +876,9 @@ macro_rules! _init_tlv_based_struct_field {
	($field: ident, (default_value, $default: expr)) => {
 $field.0.unwrap()
	};
	($field: ident, (default_value_vec, $default: expr)) => {
 $crate::_init_tlv_based_struct_field!($field, (default_value, $default))
	};
	($field: ident, (static_value, $value: expr)) => {
 $field
	};
Expand DownExpand Up@@ -905,6 +930,9 @@ macro_rules! _init_tlv_field_var {
	($field: ident, (default_value, $default: expr)) => {
 let mut $field = $crate::util::ser::RequiredWrapper(None);
	};
	($field: ident, (default_value_vec, $default: expr)) => {
 $crate::_init_tlv_field_var!($field, (default_value, $default));
	};
	($field: ident, (static_value, $value: expr)) => {
 let $field;
	};
Expand DownExpand Up@@ -1007,6 +1035,9 @@ macro_rules! _decode_and_build {
///
/// If `$fieldty` is `required`, then `$field` is a required field that is not an [`Option`] nor a [`Vec`].
/// If `$fieldty` is `(default_value, $default)`, then `$field` will be set to `$default` if not present.
/// If `$fieldty` is `(default_value_vec, $default)`, then `$field` is a [`Vec`] which will be set to `$default`
/// if not present. Elements are serialized individually without a count prefix (like `required_vec`).
/// The TLV is always written, even if the vec is empty (matching `default_value` behavior).
/// If `$fieldty` is `(static_value, $static)`, then `$field` will be set to `$static`.
/// If `$fieldty` is `option`, then `$field` is optional field.
/// If `$fieldty` is `upgradable_option`, then `$field` is optional and read via [`MaybeReadable`].
Expand All@@ -1019,7 +1050,7 @@ macro_rules! _decode_and_build {
/// `Some`. When reading, an optional field of type `$ty` is read, and after all TLV fields are
/// read, the `$read` closure is called with the `Option<&$ty>` value. The `$read` closure should
/// return a `Result<(), DecodeError>`. Legacy field values can be used in later
/// `default_value` or `static_value` fields by referring to the value by name.
/// `default_value`, `default_value_vec`, or `static_value` fields by referring to the value by name.
/// If `$fieldty` is `(custom, $ty, $read, $write)` then, when writing, the same behavior as
/// `legacy`, above is used. When reading, if a TLV is present, it is read as `$ty` and the
/// `$read` method is called with `Some(decoded_$ty_object)`. If no TLV is present, the field
Expand DownExpand Up@@ -1956,6 +1987,59 @@ mod tests {
 assert_eq!(read, ExpandedField { new_field: (42, 0) });
	}

	#[derive(Debug, PartialEq, Eq)]
	struct DefaultValueVecStruct {
 items: Vec<u32>,
	}
	impl_writeable_tlv_based!(DefaultValueVecStruct, {
 (1, items, (default_value_vec, vec![4, 5, 6])),
	});

	#[test]
	fn test_default_value_vec() {
 // Non-empty vec round-trips correctly.
 let instance = DefaultValueVecStruct { items: vec![1, 2, 3] };
 let encoded = instance.encode();
 let decoded: DefaultValueVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, instance);

 // Empty TLV stream falls back to the default.
 let empty_encoded = <Vec<u8>>::from_hex("00").unwrap(); // zero-length TLV stream
 let decoded: DefaultValueVecStruct = Readable::read(&mut &empty_encoded[..]).unwrap();
 assert_eq!(decoded, DefaultValueVecStruct { items: vec![4, 5, 6] });

 // Empty vec round-trips to empty vec (TLV is always written).
 let empty_vec = DefaultValueVecStruct { items: vec![] };
 let encoded = empty_vec.encode();
 let decoded: DefaultValueVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, DefaultValueVecStruct { items: vec![] });
	}

	#[derive(Debug, PartialEq, Eq)]
	struct LegacyToVecStruct {
 new_items: Vec<u32>,
	}
	impl_writeable_tlv_based!(LegacyToVecStruct, {
 (0, old_item, (legacy, u32, |_| Ok(()),
 |us: &LegacyToVecStruct| us.new_items.first().copied())),
 (1, new_items, (default_value_vec,
 old_item.map(|v| vec![v]).unwrap_or_default())),
	});

	#[test]
	fn test_default_value_vec_with_legacy_fallback() {
 // New format: round-trips via the new TLV.
 let instance = LegacyToVecStruct { new_items: vec![10, 20, 30] };
 let encoded = instance.encode();
 let decoded: LegacyToVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, instance);

 // Old format: only the legacy type-0 field is present, falls back via default expression.
 let old_encoded = <Vec<u8>>::from_hex("0600040000002a").unwrap(); // TLV len 6, type 0, len 4, value 42u32

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@jkczyzjkczyzMar 31, 2026

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nit: can make another struct for this.
 let decoded: LegacyToVecStruct = Readable::read(&mut &old_encoded[..]).unwrap();
 assert_eq!(decoded, LegacyToVecStruct { new_items: vec![42] });
	}

	#[test]
	fn required_vec_with_encoding() {
 // Ensure that serializing a required vec with a specified encoding will survive a ser round
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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util: add default_value_vec for defaults without LengthReadable#4507

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 Merged

TheBlueMatt
merged 1 commit into

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Apr 1, 2026
 Merged


util: add default_value_vec for defaults without LengthReadable
#4507
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86 changes: 85 additions & 1 deletion
lightning/src/util/ser_macros.rs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -21,6 +21,9 @@ macro_rules! _encode_tlv {
	($stream: expr, $type: expr, $field: expr, (default_value, $default: expr) $(, $self: ident)?) => {
 $crate::_encode_tlv!($stream, $type, $field, required)
	};
	($stream: expr, $type: expr, $field: expr, (default_value_vec, $default: expr) $(, $self: ident)?) => {
 $crate::_encode_tlv!($stream, $type, $field, required_vec)
	};
	($stream: expr, $type: expr, $field: expr, (static_value, $value: expr) $(, $self: ident)?) => {
 let _ = &$field; // Ensure we "use" the $field
	};
Expand DownExpand Up@@ -200,6 +203,9 @@ macro_rules! _get_varint_length_prefixed_tlv_length {
	($len: expr, $type: expr, $field: expr, (default_value, $default: expr) $(, $self: ident)?) => {
 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required)
	};
	($len: expr, $type: expr, $field: expr, (default_value_vec, $default: expr) $(, $self: ident)?) => {
 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required_vec)
	};
	($len: expr, $type: expr, $field: expr, (static_value, $value: expr) $(, $self: ident)?) => {};
	($len: expr, $type: expr, $field: expr, required $(, $self: ident)?) => {
 BigSize($type).write(&mut $len).expect("No in-memory data may fail to serialize");
Expand DownExpand Up@@ -301,6 +307,15 @@ macro_rules! _check_decoded_tlv_order {
 $field = $default.into();
 }
	}};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 $crate::_check_decoded_tlv_order!(
 $last_seen_type,
 $typ,
 $type,
 $field,
 (default_value, $default)
 );
	}};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (static_value, $value: expr)) => {};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, required) => {{
 // Note that $type may be 0 making the second comparison always false
Expand DownExpand Up@@ -372,6 +387,9 @@ macro_rules! _check_missing_tlv {
 $field = $default.into();
 }
	}};
	($last_seen_type: expr, $type: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 $crate::_check_missing_tlv!($last_seen_type, $type, $field, (default_value, $default));
	}};
	($last_seen_type: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
 $field = $value;
	};
Expand DownExpand Up@@ -440,6 +458,10 @@ macro_rules! _decode_tlv {
	($outer_reader: expr, $reader: expr, $field: ident, (default_value, $default: expr)) => {{
 $crate::_decode_tlv!($outer_reader, $reader, $field, required)
	}};
	($outer_reader: expr, $reader: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::LengthReadable::read_from_fixed_length_buffer(&mut $reader)?;
 $field = $crate::util::ser::RequiredWrapper(Some(f.0));
	}};
	($outer_reader: expr, $reader: expr, $field: ident, (static_value, $value: expr)) => {{
	}};
	($outer_reader: expr, $reader: expr, $field: ident, required) => {{
Expand DownExpand Up@@ -854,6 +876,9 @@ macro_rules! _init_tlv_based_struct_field {
	($field: ident, (default_value, $default: expr)) => {
 $field.0.unwrap()
	};
	($field: ident, (default_value_vec, $default: expr)) => {
 $crate::_init_tlv_based_struct_field!($field, (default_value, $default))
	};
	($field: ident, (static_value, $value: expr)) => {
 $field
	};
Expand DownExpand Up@@ -905,6 +930,9 @@ macro_rules! _init_tlv_field_var {
	($field: ident, (default_value, $default: expr)) => {
 let mut $field = $crate::util::ser::RequiredWrapper(None);
	};
	($field: ident, (default_value_vec, $default: expr)) => {
 $crate::_init_tlv_field_var!($field, (default_value, $default));
	};
	($field: ident, (static_value, $value: expr)) => {
 let $field;
	};
Expand DownExpand Up@@ -1007,6 +1035,9 @@ macro_rules! _decode_and_build {
///
/// If `$fieldty` is `required`, then `$field` is a required field that is not an [`Option`] nor a [`Vec`].
/// If `$fieldty` is `(default_value, $default)`, then `$field` will be set to `$default` if not present.
/// If `$fieldty` is `(default_value_vec, $default)`, then `$field` is a [`Vec`] which will be set to `$default`
/// if not present. Elements are serialized individually without a count prefix (like `required_vec`).
/// The TLV is always written, even if the vec is empty (matching `default_value` behavior).
/// If `$fieldty` is `(static_value, $static)`, then `$field` will be set to `$static`.
/// If `$fieldty` is `option`, then `$field` is optional field.
/// If `$fieldty` is `upgradable_option`, then `$field` is optional and read via [`MaybeReadable`].
Expand All@@ -1019,7 +1050,7 @@ macro_rules! _decode_and_build {
/// `Some`. When reading, an optional field of type `$ty` is read, and after all TLV fields are
/// read, the `$read` closure is called with the `Option<&$ty>` value. The `$read` closure should
/// return a `Result<(), DecodeError>`. Legacy field values can be used in later
/// `default_value` or `static_value` fields by referring to the value by name.
/// `default_value`, `default_value_vec`, or `static_value` fields by referring to the value by name.
/// If `$fieldty` is `(custom, $ty, $read, $write)` then, when writing, the same behavior as
/// `legacy`, above is used. When reading, if a TLV is present, it is read as `$ty` and the
/// `$read` method is called with `Some(decoded_$ty_object)`. If no TLV is present, the field
Expand DownExpand Up@@ -1956,6 +1987,59 @@ mod tests {
 assert_eq!(read, ExpandedField { new_field: (42, 0) });
	}

	#[derive(Debug, PartialEq, Eq)]
	struct DefaultValueVecStruct {
 items: Vec<u32>,
	}
	impl_writeable_tlv_based!(DefaultValueVecStruct, {
 (1, items, (default_value_vec, vec![4, 5, 6])),
	});

	#[test]
	fn test_default_value_vec() {
 // Non-empty vec round-trips correctly.
 let instance = DefaultValueVecStruct { items: vec![1, 2, 3] };
 let encoded = instance.encode();
 let decoded: DefaultValueVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, instance);

 // Empty TLV stream falls back to the default.
 let empty_encoded = <Vec<u8>>::from_hex("00").unwrap(); // zero-length TLV stream
 let decoded: DefaultValueVecStruct = Readable::read(&mut &empty_encoded[..]).unwrap();
 assert_eq!(decoded, DefaultValueVecStruct { items: vec![4, 5, 6] });

 // Empty vec round-trips to empty vec (TLV is always written).
 let empty_vec = DefaultValueVecStruct { items: vec![] };
 let encoded = empty_vec.encode();
 let decoded: DefaultValueVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, DefaultValueVecStruct { items: vec![] });
	}

	#[derive(Debug, PartialEq, Eq)]
	struct LegacyToVecStruct {
 new_items: Vec<u32>,
	}
	impl_writeable_tlv_based!(LegacyToVecStruct, {
 (0, old_item, (legacy, u32, |_| Ok(()),
 |us: &LegacyToVecStruct| us.new_items.first().copied())),
 (1, new_items, (default_value_vec,
 old_item.map(|v| vec![v]).unwrap_or_default())),
	});

	#[test]
	fn test_default_value_vec_with_legacy_fallback() {
 // New format: round-trips via the new TLV.
 let instance = LegacyToVecStruct { new_items: vec![10, 20, 30] };
 let encoded = instance.encode();
 let decoded: LegacyToVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, instance);

 // Old format: only the legacy type-0 field is present, falls back via default expression.
 let old_encoded = <Vec<u8>>::from_hex("0600040000002a").unwrap(); // TLV len 6, type 0, len 4, value 42u32

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@jkczyzjkczyzMar 31, 2026

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nit: can make another struct for this.
 let decoded: LegacyToVecStruct = Readable::read(&mut &old_encoded[..]).unwrap();
 assert_eq!(decoded, LegacyToVecStruct { new_items: vec![42] });
	}

	#[test]
	fn required_vec_with_encoding() {
 // Ensure that serializing a required vec with a specified encoding will survive a ser round
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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util: add default_value_vec for defaults without LengthReadable#4507

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 Merged

TheBlueMatt
merged 1 commit into

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Apr 1, 2026
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util: add default_value_vec for defaults without LengthReadable
#4507
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86 changes: 85 additions & 1 deletion
lightning/src/util/ser_macros.rs

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Original file line numberDiff line numberDiff line change
Expand Up@@ -21,6 +21,9 @@ macro_rules! _encode_tlv {
	($stream: expr, $type: expr, $field: expr, (default_value, $default: expr) $(, $self: ident)?) => {
 $crate::_encode_tlv!($stream, $type, $field, required)
	};
	($stream: expr, $type: expr, $field: expr, (default_value_vec, $default: expr) $(, $self: ident)?) => {
 $crate::_encode_tlv!($stream, $type, $field, required_vec)
	};
	($stream: expr, $type: expr, $field: expr, (static_value, $value: expr) $(, $self: ident)?) => {
 let _ = &$field; // Ensure we "use" the $field
	};
Expand DownExpand Up@@ -200,6 +203,9 @@ macro_rules! _get_varint_length_prefixed_tlv_length {
	($len: expr, $type: expr, $field: expr, (default_value, $default: expr) $(, $self: ident)?) => {
 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required)
	};
	($len: expr, $type: expr, $field: expr, (default_value_vec, $default: expr) $(, $self: ident)?) => {
 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required_vec)
	};
	($len: expr, $type: expr, $field: expr, (static_value, $value: expr) $(, $self: ident)?) => {};
	($len: expr, $type: expr, $field: expr, required $(, $self: ident)?) => {
 BigSize($type).write(&mut $len).expect("No in-memory data may fail to serialize");
Expand DownExpand Up@@ -301,6 +307,15 @@ macro_rules! _check_decoded_tlv_order {
 $field = $default.into();
 }
	}};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 $crate::_check_decoded_tlv_order!(
 $last_seen_type,
 $typ,
 $type,
 $field,
 (default_value, $default)
 );
	}};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (static_value, $value: expr)) => {};
	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, required) => {{
 // Note that $type may be 0 making the second comparison always false
Expand DownExpand Up@@ -372,6 +387,9 @@ macro_rules! _check_missing_tlv {
 $field = $default.into();
 }
	}};
	($last_seen_type: expr, $type: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 $crate::_check_missing_tlv!($last_seen_type, $type, $field, (default_value, $default));
	}};
	($last_seen_type: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
 $field = $value;
	};
Expand DownExpand Up@@ -440,6 +458,10 @@ macro_rules! _decode_tlv {
	($outer_reader: expr, $reader: expr, $field: ident, (default_value, $default: expr)) => {{
 $crate::_decode_tlv!($outer_reader, $reader, $field, required)
	}};
	($outer_reader: expr, $reader: expr, $field: ident, (default_value_vec, $default: expr)) => {{
 let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::LengthReadable::read_from_fixed_length_buffer(&mut $reader)?;
 $field = $crate::util::ser::RequiredWrapper(Some(f.0));
	}};
	($outer_reader: expr, $reader: expr, $field: ident, (static_value, $value: expr)) => {{
	}};
	($outer_reader: expr, $reader: expr, $field: ident, required) => {{
Expand DownExpand Up@@ -854,6 +876,9 @@ macro_rules! _init_tlv_based_struct_field {
	($field: ident, (default_value, $default: expr)) => {
 $field.0.unwrap()
	};
	($field: ident, (default_value_vec, $default: expr)) => {
 $crate::_init_tlv_based_struct_field!($field, (default_value, $default))
	};
	($field: ident, (static_value, $value: expr)) => {
 $field
	};
Expand DownExpand Up@@ -905,6 +930,9 @@ macro_rules! _init_tlv_field_var {
	($field: ident, (default_value, $default: expr)) => {
 let mut $field = $crate::util::ser::RequiredWrapper(None);
	};
	($field: ident, (default_value_vec, $default: expr)) => {
 $crate::_init_tlv_field_var!($field, (default_value, $default));
	};
	($field: ident, (static_value, $value: expr)) => {
 let $field;
	};
Expand DownExpand Up@@ -1007,6 +1035,9 @@ macro_rules! _decode_and_build {
///
/// If `$fieldty` is `required`, then `$field` is a required field that is not an [`Option`] nor a [`Vec`].
/// If `$fieldty` is `(default_value, $default)`, then `$field` will be set to `$default` if not present.
/// If `$fieldty` is `(default_value_vec, $default)`, then `$field` is a [`Vec`] which will be set to `$default`
/// if not present. Elements are serialized individually without a count prefix (like `required_vec`).
/// The TLV is always written, even if the vec is empty (matching `default_value` behavior).
/// If `$fieldty` is `(static_value, $static)`, then `$field` will be set to `$static`.
/// If `$fieldty` is `option`, then `$field` is optional field.
/// If `$fieldty` is `upgradable_option`, then `$field` is optional and read via [`MaybeReadable`].
Expand All@@ -1019,7 +1050,7 @@ macro_rules! _decode_and_build {
/// `Some`. When reading, an optional field of type `$ty` is read, and after all TLV fields are
/// read, the `$read` closure is called with the `Option<&$ty>` value. The `$read` closure should
/// return a `Result<(), DecodeError>`. Legacy field values can be used in later
/// `default_value` or `static_value` fields by referring to the value by name.
/// `default_value`, `default_value_vec`, or `static_value` fields by referring to the value by name.
/// If `$fieldty` is `(custom, $ty, $read, $write)` then, when writing, the same behavior as
/// `legacy`, above is used. When reading, if a TLV is present, it is read as `$ty` and the
/// `$read` method is called with `Some(decoded_$ty_object)`. If no TLV is present, the field
Expand DownExpand Up@@ -1956,6 +1987,59 @@ mod tests {
 assert_eq!(read, ExpandedField { new_field: (42, 0) });
	}

	#[derive(Debug, PartialEq, Eq)]
	struct DefaultValueVecStruct {
 items: Vec<u32>,
	}
	impl_writeable_tlv_based!(DefaultValueVecStruct, {
 (1, items, (default_value_vec, vec![4, 5, 6])),
	});

	#[test]
	fn test_default_value_vec() {
 // Non-empty vec round-trips correctly.
 let instance = DefaultValueVecStruct { items: vec![1, 2, 3] };
 let encoded = instance.encode();
 let decoded: DefaultValueVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, instance);

 // Empty TLV stream falls back to the default.
 let empty_encoded = <Vec<u8>>::from_hex("00").unwrap(); // zero-length TLV stream
 let decoded: DefaultValueVecStruct = Readable::read(&mut &empty_encoded[..]).unwrap();
 assert_eq!(decoded, DefaultValueVecStruct { items: vec![4, 5, 6] });

 // Empty vec round-trips to empty vec (TLV is always written).
 let empty_vec = DefaultValueVecStruct { items: vec![] };
 let encoded = empty_vec.encode();
 let decoded: DefaultValueVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, DefaultValueVecStruct { items: vec![] });
	}

	#[derive(Debug, PartialEq, Eq)]
	struct LegacyToVecStruct {
 new_items: Vec<u32>,
	}
	impl_writeable_tlv_based!(LegacyToVecStruct, {
 (0, old_item, (legacy, u32, |_| Ok(()),
 |us: &LegacyToVecStruct| us.new_items.first().copied())),
 (1, new_items, (default_value_vec,
 old_item.map(|v| vec![v]).unwrap_or_default())),
	});

	#[test]
	fn test_default_value_vec_with_legacy_fallback() {
 // New format: round-trips via the new TLV.
 let instance = LegacyToVecStruct { new_items: vec![10, 20, 30] };
 let encoded = instance.encode();
 let decoded: LegacyToVecStruct = Readable::read(&mut &encoded[..]).unwrap();
 assert_eq!(decoded, instance);

 // Old format: only the legacy type-0 field is present, falls back via default expression.
 let old_encoded = <Vec<u8>>::from_hex("0600040000002a").unwrap(); // TLV len 6, type 0, len 4, value 42u32

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+2037
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+2038

@jkczyzjkczyzMar 31, 2026

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nit: can make another struct for this.
 let decoded: LegacyToVecStruct = Readable::read(&mut &old_encoded[..]).unwrap();
 assert_eq!(decoded, LegacyToVecStruct { new_items: vec![42] });
	}

	#[test]
	fn required_vec_with_encoding() {
 // Ensure that serializing a required vec with a specified encoding will survive a ser round
Expand Down
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