Remove longestMatch in _WithPrefix iterators (#16689)

changelog.md

@@ -46,8 +46,8 @@
 - Added `asyncdispatch.activeDescriptors` that returns the number of currently
   active async event handles/file descriptors.
 
-- ``--gc:orc`` is now 10% faster than previously for common workloads. If
+- `--gc:orc` is now 10% faster than previously for common workloads. If
-  you have trouble with its changed behavior, compile with ``-d:nimOldOrc``.
+  you have trouble with its changed behavior, compile with `-d:nimOldOrc`.
 
 
 - `os.FileInfo` (returned by `getFileInfo`) now contains `blockSize`,
@@ -96,11 +96,10 @@
 with other backends. see #9125. Use `-d:nimLegacyJsRound` for previous behavior.
 - Added `socketstream` module that wraps sockets in the stream interface
 
-
-
-
 - Added `math.signbit`.
 
+- Removed the optional `longestMatch` parameter of the `critbits._WithPrefix` iterators (it never worked reliably)
+
 ## Language changes
 
 - `nimscript` now handles `except Exception as e`.

lib/pure/collections/critbits.nim

@@ -390,8 +390,7 @@ iterator mpairs*[T](c: var CritBitTree[T]): tuple[key: string, val: var T] =
   ## * `pairs iterator <#pairs.i,CritBitTree[T]>`_
   for x in leaves(c.root): yield (x.key, x.val)
 
-proc allprefixedAux[T](c: CritBitTree[T], key: string;
+proc allprefixedAux[T](c: CritBitTree[T], key: string): Node[T] =
-                       longestMatch: bool): Node[T] =
   var p = c.root
   var top = p
   if p != nil:
@@ -401,13 +400,11 @@ proc allprefixedAux[T](c: CritBitTree[T], key: string;
       let dir = (1 + (ch.ord or p.otherBits.ord)) shr 8
       p = p.child[dir]
       if q.byte < key.len: top = p
-    if not longestMatch:
+    for i in 0 ..< key.len:
-      for i in 0 ..< key.len:
+      if i >= p.key.len or p.key[i] != key[i]: return
-        if i >= p.key.len or p.key[i] != key[i]: return
     result = top
 
-iterator keysWithPrefix*[T](c: CritBitTree[T], prefix: string;
+iterator keysWithPrefix*[T](c: CritBitTree[T], prefix: string): string =
-                            longestMatch = false): string =
   ## Yields all keys starting with `prefix`.
   runnableExamples:
     from sequtils import toSeq
@@ -415,11 +412,10 @@ iterator keysWithPrefix*[T](c: CritBitTree[T], prefix: string;
     let c = {"key1": 42, "key2": 43}.toCritBitTree
     doAssert toSeq(c.keysWithPrefix("key")) == @["key1", "key2"]
 
-  let top = allprefixedAux(c, prefix, longestMatch)
+  let top = allprefixedAux(c, prefix)
   for x in leaves(top): yield x.key
 
-iterator valuesWithPrefix*[T](c: CritBitTree[T], prefix: string;
+iterator valuesWithPrefix*[T](c: CritBitTree[T], prefix: string): T =
-                              longestMatch = false): T =
   ## Yields all values of `c` starting with `prefix` of the
   ## corresponding keys.
   ##
@@ -431,28 +427,25 @@ iterator valuesWithPrefix*[T](c: CritBitTree[T], prefix: string;
     let c = {"key1": 42, "key2": 43}.toCritBitTree
     doAssert toSeq(c.valuesWithPrefix("key")) == @[42, 43]
 
-  let top = allprefixedAux(c, prefix, longestMatch)
+  let top = allprefixedAux(c, prefix)
   for x in leaves(top): yield x.val
 
-iterator mvaluesWithPrefix*[T](c: var CritBitTree[T], prefix: string;
+iterator mvaluesWithPrefix*[T](c: var CritBitTree[T], prefix: string): var T =
-                               longestMatch = false): var T =
   ## Yields all values of `c` starting with `prefix` of the
   ## corresponding keys. The values can be modified.
   ##
   ## **See also:**
   ## * `valuesWithPrefix iterator <#valuesWithPrefix.i,CritBitTree[T],string>`_
-  let top = allprefixedAux(c, prefix, longestMatch)
+  let top = allprefixedAux(c, prefix)
   for x in leaves(top): yield x.val
 
-iterator itemsWithPrefix*[T](c: CritBitTree[T], prefix: string;
+iterator itemsWithPrefix*[T](c: CritBitTree[T], prefix: string): string =
-                             longestMatch = false): string =
   ## Alias for `keysWithPrefix <#keysWithPrefix.i,CritBitTree[T],string>`_.
-  let top = allprefixedAux(c, prefix, longestMatch)
+  let top = allprefixedAux(c, prefix)
   for x in leaves(top): yield x.key
 
 iterator pairsWithPrefix*[T](c: CritBitTree[T],
-                             prefix: string;
+                             prefix: string): tuple[key: string, val: T] =
-                             longestMatch = false): tuple[key: string, val: T] =
   ## Yields all (key, value)-pairs of `c` starting with `prefix`.
   ##
   ## **See also:**
@@ -463,18 +456,17 @@ iterator pairsWithPrefix*[T](c: CritBitTree[T],
     let c = {"key1": 42, "key2": 43}.toCritBitTree
     doAssert toSeq(c.pairsWithPrefix("key")) == @[(key: "key1", val: 42), (key: "key2", val: 43)]
 
-  let top = allprefixedAux(c, prefix, longestMatch)
+  let top = allprefixedAux(c, prefix)
   for x in leaves(top): yield (x.key, x.val)
 
 iterator mpairsWithPrefix*[T](c: var CritBitTree[T],
-                              prefix: string;
+                              prefix: string): tuple[key: string, val: var T] =
-                              longestMatch = false): tuple[key: string, val: var T] =
   ## Yields all (key, value)-pairs of `c` starting with `prefix`.
   ## The yielded values can be modified.
   ##
   ## **See also:**
   ## * `pairsWithPrefix iterator <#pairsWithPrefix.i,CritBitTree[T],string>`_
-  let top = allprefixedAux(c, prefix, longestMatch)
+  let top = allprefixedAux(c, prefix)
   for x in leaves(top): yield (x.key, x.val)
 
 func `$`*[T](c: CritBitTree[T]): string =