Derive reserved rune names from rune ID (ordinals#3412)

crates/ordinals/src/rune.rs

@@ -88,8 +88,12 @@ impl Rune {
     self.0 >= Self::RESERVED
   }
 
-  pub fn reserved(n: u128) -> Option<Self> {
-    Some(Rune(Self::RESERVED.checked_add(n)?))
+  pub fn reserved(block: u64, tx: u32) -> Self {
+    Self(
+      Self::RESERVED
+        .checked_add(u128::from(block) << 32 | u128::from(tx))
+        .unwrap(),
+    )
   }
 
   pub fn commitment(self) -> Vec<u8> {
@@ -360,13 +364,14 @@ mod tests {
       "AAAAAAAAAAAAAAAAAAAAAAAAAAA".parse::<Rune>().unwrap().0,
     );
 
-    assert_eq!(Rune::reserved(0), Some(Rune(Rune::RESERVED)));
-    assert_eq!(Rune::reserved(1), Some(Rune(Rune::RESERVED + 1)));
+    assert_eq!(Rune::reserved(0, 0), Rune(Rune::RESERVED));
+    assert_eq!(Rune::reserved(0, 1), Rune(Rune::RESERVED + 1));
+    assert_eq!(Rune::reserved(1, 0), Rune(Rune::RESERVED + (1 << 32)));
+    assert_eq!(Rune::reserved(1, 1), Rune(Rune::RESERVED + (1 << 32) + 1));
     assert_eq!(
-      Rune::reserved(u128::MAX - Rune::RESERVED),
-      Some(Rune(u128::MAX))
+      Rune::reserved(u64::MAX, u32::MAX),
+      Rune(Rune::RESERVED + (u128::from(u64::MAX) << 32 | u128::from(u32::MAX))),
     );
-    assert_eq!(Rune::reserved(u128::MAX - Rune::RESERVED + 1), None);
   }
 
   #[test]

docs/src/runes/specification.md

@@ -276,9 +276,8 @@ runestone is a cenotaph.
 ##### Rune
 
 The `Rune` field contains the name of the rune being etched. If the `Etching`
-flag is set, but the `Rune` field is omitted, a reserved rune name is
-allocated, starting with `AAAAAAAAAAAAAAAAAAAAAAAAAAA` and increasing by one
-with each such reserved rune allocated.
+flag is set but the `Rune` field is omitted, a reserved rune name is
+allocated.
 
 ##### Premine
 
@@ -428,8 +427,19 @@ And so on and so on.
 
 Rune names `AAAAAAAAAAAAAAAAAAAAAAAAAAA` and above are reserved.
 
-`rune` may be omitted, in which case the first unallocated rune name, starting
-at `AAAAAAAAAAAAAAAAAAAAAAAAAAA` and increasing by one each time, is etched.
+If `rune` is omitted a reserved rune name is allocated as follows:
+
+```rust
+fn reserve(block: u64, tx: u32) -> Rune {
+  Rune(
+    6402364363415443603228541259936211926
+    + (u128::from(block) << 32 | u128::from(tx))
+  )
+}
+```
+
+`6402364363415443603228541259936211926` corresponds to the rune name
+`AAAAAAAAAAAAAAAAAAAAAAAAAAA`.
 
 If `rune` is present, it must be unlocked as of the block in which the etching
 appears.

src/index/updater/rune_updater.rs

@@ -308,7 +308,7 @@ impl<'a, 'tx, 'client> RuneUpdater<'a, 'tx, 'client> {
         .statistic_to_count
         .insert(&Statistic::ReservedRunes.into(), reserved_runes + 1)?;
 
-      Rune::reserved(reserved_runes.into()).unwrap()
+      Rune::reserved(self.height.into(), tx_index)
     };
 
     Ok(Some(Etched {

src/runes.rs

@@ -230,7 +230,7 @@ mod tests {
             output: 0,
           }],
           etching: Some(Etching {
-            rune: Some(Rune::reserved(0).unwrap()),
+            rune: Some(Rune::reserved(0, 0)),
             ..default()
           }),
           ..default()
@@ -252,7 +252,7 @@ mod tests {
             output: 0,
           }],
           etching: Some(Etching {
-            rune: Some(Rune(Rune::reserved(0).unwrap().n() - 1)),
+            rune: Some(Rune(Rune::reserved(0, 0).n() - 1)),
             premine: Some(u128::MAX),
             ..default()
           }),
@@ -268,7 +268,7 @@ mod tests {
             block: id.block,
             etching: txid,
             spaced_rune: SpacedRune {
-              rune: Rune(Rune::reserved(0).unwrap().n() - 1),
+              rune: Rune(Rune::reserved(0, 0).n() - 1),
               spacers: 0,
             },
             premine: u128::MAX,
@@ -320,7 +320,7 @@ mod tests {
           block: id0.block,
           etching: txid0,
           spaced_rune: SpacedRune {
-            rune: Rune::reserved(0).unwrap(),
+            rune: Rune::reserved(id0.block, id0.tx),
             spacers: 0,
           },
           premine: u128::MAX,
@@ -372,7 +372,7 @@ mod tests {
             block: id0.block,
             etching: txid0,
             spaced_rune: SpacedRune {
-              rune: Rune::reserved(0).unwrap(),
+              rune: Rune::reserved(id0.block, id0.tx),
               spacers: 0,
             },
             premine: u128::MAX,
@@ -386,7 +386,7 @@ mod tests {
             block: id1.block,
             etching: txid1,
             spaced_rune: SpacedRune {
-              rune: Rune::reserved(1).unwrap(),
+              rune: Rune::reserved(id1.block, id0.tx),
               spacers: 0,
             },
             premine: u128::MAX,
@@ -907,7 +907,7 @@ mod tests {
           block: id.block,
           etching: txid0,
           spaced_rune: SpacedRune {
-            rune: Rune::reserved(0).unwrap(),
+            rune: Rune::reserved(2, 1),
             spacers: 0,
           },
           timestamp: id.block,

tests/wallet/batch_command.rs

@@ -1707,7 +1707,7 @@ fn etch_reserved_rune_error() {
         etching: Some(batch::Etching {
           divisibility: 0,
           rune: SpacedRune {
-            rune: Rune::reserved(0).unwrap(),
+            rune: Rune::reserved(0, 0),
             spacers: 0,
           },
           premine: "1000".parse().unwrap(),