chore: v0.2.1 (#6)

* Change the LevelDbCmakeFlags option case

* Add nimbledeps to ignored files

* Increase version

* Add Nim 2.0.12 to the matrix

* Fixes STD_REGEX issue introduced by gtest/benchmark submodule

* Revert "Fixes STD_REGEX issue introduced by gtest/benchmark submodule"

This reverts commit b4db94d75300f9d638869279ab736571eda632e6.

* Disables building benchmark tests

---------

Co-authored-by: Arnaud <arnaud@status.im>

.github/workflows/main.yml

@@ -8,14 +8,15 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, macOS-latest, windows-latest]
-        nim: [stable, 1.6.18]
+        nim: [stable, 1.6.18, 2.0.12]
     steps:
     - uses: actions/checkout@v2
       with:
         submodules: true
-    - uses: iffy/install-nim@v4
+    - uses: jiro4989/setup-nim-action@v2
       with:
-        version: ${{ matrix.nim }}
+        nim-version: ${{matrix.nim}}
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Build
       run: nimble install -y
     - name: Test

.gitignore

@@ -8,4 +8,5 @@ leveldbtool
 *.html
 *.css
 build
-
+nimbledeps
+*.exe

README.md

@@ -6,6 +6,8 @@ Original nim LevelDB wrapper: [HERE](https://github.com/zielmicha/leveldb.nim)
 
 Replacing of system library dependency with self-contained C/CPP interoperability by (Codex.Storage)[https://codex.storage]
 
+## Usage
+
 Create a database:
 ```Nim
    import leveldbstatic
@@ -49,3 +51,25 @@ Iterate over subset of database content:
 
    db.close()
 ```
+
+## Compiling with optimizations
+
+CMake is used during compilation to determine which of the following optimization options are enabled. You can set the following nim compiler flags to 0 or 1 to override them:
+ - fdatasync from <unistd.h> `--passC:-DHAVE_FDATASYNC=1`
+ - F_FULLSYNC from <fcntl.h> `--passC:-DHAVE_FULLFSYNC=1`
+ - O_CLOEXEC from <fcntl.h> `--passC:-DHAVE_O_CLOEXEC=1`
+ - crc32c from <crc32c/crc32c.h> `--passC:-DHAVE_CRC32C=1`
+ - snappy from <snappy.h> `--passC:-DHAVE_SNAPPY=1`
+ - zstd from <zstd.h> `--passC:-DHAVE_ZSTD=1`
+
+## Updating
+
+When you want to update this library to a new version of LevelDB, follow these steps:
+- Update LevelDB submodule to new version.
+- Run 'build.sh'.
+- Run 'nimble build' and 'nimble test'.
+- Make sure everything's working.
+- Increment version of this library in 'leveldbstatic.nimble'.
+- Commit the changes.
+- Tag the commit with the new version number.
+- Push.

build.sh

@@ -21,7 +21,7 @@ rm -Rf "${sourceDir}/benchmarks"
 rm "${sourceDir}/util/testutil.cc"
 
 # Prelude:
-cat "${root}/leveldb/prelude.nim" > "${output}"
+cat "${root}/leveldbstatic/prelude.nim" > "${output}"
 echo >> "${output}"
 
 # assemble files to be compiled:
@@ -47,10 +47,8 @@ toast \
   --includeDirs="${sourceDir}/helpers/memenv" \
   --includeDirs="${sourceDir}/port" \
   --includeDirs="${sourceDir}/include" \
-  --includeDirs="${buildDir}/include" \
   "${sourceDir}/include/leveldb/c.h" >> "${output}"
 
 sed -i 's/\bpassC\b/passc/g' "${output}"
 sed -i 's/{\.compile\:\ \"\./{\.compile\:\ root\ \&\ \"/g' "${output}"
 sed -i 's/{\.passc\:\ \"-I\./{\.passc\:\ \"-I\"\ \&\ root\ \&\ \"/g' "${output}"
-

build/include/port/port_config.h

@@ -1,38 +0,0 @@
-// Copyright 2017 The LevelDB Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file. See the AUTHORS file for names of contributors.
-
-#ifndef STORAGE_LEVELDB_PORT_PORT_CONFIG_H_
-#define STORAGE_LEVELDB_PORT_PORT_CONFIG_H_
-
-// Define to 1 if you have a definition for fdatasync() in <unistd.h>.
-#if !defined(HAVE_FDATASYNC)
-#define HAVE_FDATASYNC 1
-#endif  // !defined(HAVE_FDATASYNC)
-
-// Define to 1 if you have a definition for F_FULLFSYNC in <fcntl.h>.
-#if !defined(HAVE_FULLFSYNC)
-#define HAVE_FULLFSYNC 0
-#endif  // !defined(HAVE_FULLFSYNC)
-
-// Define to 1 if you have a definition for O_CLOEXEC in <fcntl.h>.
-#if !defined(HAVE_O_CLOEXEC)
-#define HAVE_O_CLOEXEC 1
-#endif  // !defined(HAVE_O_CLOEXEC)
-
-// Define to 1 if you have Google CRC32C.
-#if !defined(HAVE_CRC32C)
-#define HAVE_CRC32C 0
-#endif  // !defined(HAVE_CRC32C)
-
-// Define to 1 if you have Google Snappy.
-#if !defined(HAVE_SNAPPY)
-#define HAVE_SNAPPY 0
-#endif  // !defined(HAVE_SNAPPY)
-
-// Define to 1 if you have Zstd.
-#if !defined(HAVE_Zstd)
-#define HAVE_ZSTD 0
-#endif  // !defined(HAVE_ZSTD)
-
-#endif  // STORAGE_LEVELDB_PORT_PORT_CONFIG_H_

leveldbstatic.nim

@@ -76,6 +76,13 @@ type
 
   LevelDbException* = object of CatchableError
 
+  IterNext* = proc(): (string, string) {.gcsafe, closure, raises: [LevelDbException].}
+  IterDispose* = proc() {.gcsafe, closure, raises: [].}
+  LevelDbQueryIter* = ref object
+    finished*: bool
+    next*: IterNext
+    dispose*: IterDispose
+
 const
   version* = block:
     const configFile = "leveldbstatic.nimble"
@@ -406,6 +413,81 @@ iterator iterRange*(self: LevelDb, start, limit: string): (string, string) =
         break
     yield (key, value)
 
+
+proc getIterKey(iterPtr: ptr leveldb_iterator_t): string =
+  var len: csize_t
+  var str: cstring
+
+  str = leveldb_iter_key(iterPtr, addr len)
+  return newString(str, len)
+
+proc getIterValue(iterPtr: ptr leveldb_iterator_t): string =
+  var len: csize_t
+  var str: cstring
+
+  str = leveldb_iter_value(iterPtr, addr len)
+  return newString(str, len)
+
+proc seekToQueryStart(iterPtr: ptr leveldb_iterator_t, prefix: string, skip: int) =
+  if prefix.len > 0:
+    leveldb_iter_seek(iterPtr, prefix, prefix.len.csize_t)
+  else:
+    leveldb_iter_seek_to_first(iterPtr)
+  for i in 0..<skip:
+    leveldb_iter_next(iterPtr)
+
+proc closeIter(iter: LevelDbQueryIter, iterPtr: ptr leveldb_iterator_t) =
+  iter.finished = true
+  leveldb_iter_destroy(iterPtr)
+  
+proc queryIter*(self: LevelDb, prefix: string = "", keysOnly: bool = false, skip: int = 0, limit: int = 0): LevelDbQueryIter = 
+  var iterPtr = leveldb_create_iterator(self.db, self.readOptions)
+
+  seekToQueryStart(iterPtr, prefix, skip)
+
+  var
+    iter = LevelDbQueryIter()
+    remaining = limit
+  let emptyResponse = ("", "")
+
+  proc getNext(): (string, string) {.gcsafe, closure.} =
+    if iter.finished:
+      return emptyResponse
+    
+    if leveldb_iter_valid(iterPtr) == levelDbFalse or (limit > 0 and remaining == 0):
+      iter.closeIter(iterPtr)
+      return emptyResponse
+    if limit > 0:
+      dec remaining
+
+    let
+      keyStr = getIterKey(iterPtr)
+      valueStr = if keysOnly: "" else: getIterValue(iterPtr)
+
+    var err: cstring = nil
+    leveldb_iter_get_error(iterPtr, addr err)
+    checkError(err)
+
+    leveldb_iter_next(iterPtr)
+
+    if prefix.len > 0:
+      if keyStr.startsWith(prefix):
+        return (keyStr, valueStr)
+      else:
+        iter.closeIter(iterPtr)
+        return emptyResponse
+    else:
+      return (keyStr, valueStr)
+  
+  proc dispose() {.gcsafe, closure.} =
+    if not iter.finished:
+      iter.closeIter(iterPtr)
+
+  iter.finished = false
+  iter.next = getNext
+  iter.dispose = dispose
+  return iter
+
 proc removeDb*(name: string) =
   ## Remove the database `name`.
   var err: cstring = nil

leveldbstatic.nimble

@@ -1,6 +1,6 @@
 # Package
 
-version       = "0.1.0"
+version       = "0.2.1"
 author        = "leveldbstatic authors"
 description   = "Statically linked LevelDB wrapper for Nim"
 license       = "MIT"

leveldbstatic/prelude.nim

@@ -1,8 +1,46 @@
 import os
 
-const root = currentSourcePath.parentDir.parentDir
+const
-const envWindows = root/"vendor"/"util"/"env_windows.cc"
+  root = currentSourcePath.parentDir.parentDir
-const envPosix = root/"vendor"/"util"/"env_posix.cc"
+  envWindows = root/"vendor"/"util"/"env_windows.cc"
+  envPosix = root/"vendor"/"util"/"env_posix.cc"
+
+  LevelDbCMakeFlags {.strdefine.} =
+    when defined(macosx):
+      "-DCMAKE_BUILD_TYPE=Release -DLEVELDB_BUILD_BENCHMARKS=OFF"
+    elif defined(windows):
+      "-G\"MSYS Makefiles\" -DCMAKE_BUILD_TYPE=Release -DLEVELDB_BUILD_BENCHMARKS=OFF"
+    else:
+      "-DCMAKE_BUILD_TYPE=Release -DLEVELDB_BUILD_BENCHMARKS=OFF"
+
+  LevelDbCMakeCommonFlags = " -DCMAKE_POLICY_VERSION_MINIMUM=3.31"
+
+  LevelDbDir {.strdefine.} = $(root/"vendor")
+  buildDir = $(root/"build")
+
+proc buildLevelDb() =
+  if fileExists(buildDir/"Makefile"):
+    echo "LevelDB already build. Delete '" & buildDir & "' to force rebuild."
+    return
+
+  echo "Initializing submodule..."
+  discard gorge "git submodule deinit -f \"" & root & "\""
+  discard gorge "git submodule update --init --recursive --checkout \"" & root & "\""
+
+  echo "\nClean dir: \"" & buildDir & "\""
+  discard gorge "rm -rf " & buildDir
+  discard gorge "mkdir -p " & buildDir
+
+  let cmd = "cmake -S \"" & LevelDbDir & "\" -B \"" & buildDir & "\" " & LevelDbCMakeFlags & LevelDbCMakeCommonFlags
+  echo "\nBuilding LevelDB: " & cmd
+  let (output, exitCode) = gorgeEx cmd
+  if exitCode != 0:
+    discard gorge "rm -rf " & buildDir
+    echo output
+    raise (ref Defect)(msg: "Failed to build LevelDB")
+
+static:
+  buildLevelDb()
 
 when defined(windows):
   {.compile: envWindows.}
@@ -13,13 +51,3 @@ when defined(windows):
 when defined(posix):
   {.compile: envPosix.}
   {.passc: "-DLEVELDB_PLATFORM_POSIX".}
-
-
-{.passc: "-DHAVE_FDATASYNC=0".}
-{.passc: "-DHAVE_FULLFSYNC=0".}
-{.passc: "-DHAVE_O_CLOEXEC=0".}
-{.passc: "-DHAVE_CRC32C=0".}
-{.passc: "-DHAVE_SNAPPY=0".}
-{.passc: "-DHAVE_ZSTD=0".}
-{.passc: "-DHAVE_Zstd=0".}
-

leveldbstatic/raw.nim

@@ -1,8 +1,46 @@
 import os
 
-const root = currentSourcePath.parentDir.parentDir
+const
-const envWindows = root/"vendor"/"util"/"env_windows.cc"
+  root = currentSourcePath.parentDir.parentDir
-const envPosix = root/"vendor"/"util"/"env_posix.cc"
+  envWindows = root/"vendor"/"util"/"env_windows.cc"
+  envPosix = root/"vendor"/"util"/"env_posix.cc"
+
+  LevelDbCMakeFlags {.strdefine.} =
+    when defined(macosx):
+      "-DCMAKE_BUILD_TYPE=Release -DLEVELDB_BUILD_BENCHMARKS=OFF"
+    elif defined(windows):
+      "-G\"MSYS Makefiles\" -DCMAKE_BUILD_TYPE=Release -DLEVELDB_BUILD_BENCHMARKS=OFF"
+    else:
+      "-DCMAKE_BUILD_TYPE=Release -DLEVELDB_BUILD_BENCHMARKS=OFF"
+
+  LevelDbCMakeCommonFlags = " -DCMAKE_POLICY_VERSION_MINIMUM=3.31"
+
+  LevelDbDir {.strdefine.} = $(root/"vendor")
+  buildDir = $(root/"build")
+
+proc buildLevelDb() =
+  if fileExists(buildDir/"Makefile"):
+    echo "LevelDB already build. Delete '" & buildDir & "' to force rebuild."
+    return
+
+  echo "Initializing submodule..."
+  discard gorge "git submodule deinit -f \"" & root & "\""
+  discard gorge "git submodule update --init --recursive --checkout \"" & root & "\""
+
+  echo "\nClean dir: \"" & buildDir & "\""
+  discard gorge "rm -rf " & buildDir
+  discard gorge "mkdir -p " & buildDir
+
+  let cmd = "cmake -S \"" & LevelDbDir & "\" -B \"" & buildDir & "\" " & LevelDbCMakeFlags & LevelDbCMakeCommonFlags
+  echo "\nBuilding LevelDB: " & cmd
+  let (output, exitCode) = gorgeEx cmd
+  if exitCode != 0:
+    discard gorge "rm -rf " & buildDir
+    echo output
+    raise (ref Defect)(msg: "Failed to build LevelDB")
+
+static:
+  buildLevelDb()
 
 when defined(windows):
   {.compile: envWindows.}
@@ -14,19 +52,9 @@ when defined(posix):
   {.compile: envPosix.}
   {.passc: "-DLEVELDB_PLATFORM_POSIX".}
 
-
+# Generated @ 2024-12-09T16:35:09+01:00
-{.passc: "-DHAVE_FDATASYNC=0".}
-{.passc: "-DHAVE_FULLFSYNC=0".}
-{.passc: "-DHAVE_O_CLOEXEC=0".}
-{.passc: "-DHAVE_CRC32C=0".}
-{.passc: "-DHAVE_SNAPPY=0".}
-{.passc: "-DHAVE_ZSTD=0".}
-{.passc: "-DHAVE_Zstd=0".}
-
-
-# Generated @ 2024-05-13T12:00:58+02:00
 # Command line:
-#   /home/ben/.nimble/pkgs/nimterop-0.6.13/nimterop/toast --compile=./vendor/db/log_writer.cc --compile=./vendor/db/db_impl.cc --compile=./vendor/db/db_iter.cc --compile=./vendor/db/dumpfile.cc --compile=./vendor/db/c.cc --compile=./vendor/db/builder.cc --compile=./vendor/db/filename.cc --compile=./vendor/db/write_batch.cc --compile=./vendor/db/table_cache.cc --compile=./vendor/db/version_edit.cc --compile=./vendor/db/dbformat.cc --compile=./vendor/db/log_reader.cc --compile=./vendor/db/memtable.cc --compile=./vendor/db/version_set.cc --compile=./vendor/db/repair.cc --compile=./vendor/table/block.cc --compile=./vendor/table/two_level_iterator.cc --compile=./vendor/table/table_builder.cc --compile=./vendor/table/iterator.cc --compile=./vendor/table/block_builder.cc --compile=./vendor/table/merger.cc --compile=./vendor/table/format.cc --compile=./vendor/table/filter_block.cc --compile=./vendor/table/table.cc --compile=./vendor/util/hash.cc --compile=./vendor/util/arena.cc --compile=./vendor/util/options.cc --compile=./vendor/util/histogram.cc --compile=./vendor/util/crc32c.cc --compile=./vendor/util/env.cc --compile=./vendor/util/filter_policy.cc --compile=./vendor/util/bloom.cc --compile=./vendor/util/logging.cc --compile=./vendor/util/coding.cc --compile=./vendor/util/status.cc --compile=./vendor/util/cache.cc --compile=./vendor/util/comparator.cc --compile=./vendor/helpers/memenv/memenv.cc --pnim --preprocess --noHeader --includeDirs=./vendor --includeDirs=./vendor/helpers --includeDirs=./vendor/helpers/memenv --includeDirs=./vendor/port --includeDirs=./vendor/include --includeDirs=./build/include ./vendor/include/leveldb/c.h
+#   /home/arnaud/.nimble/pkgs2/nimterop-0.6.13-a93246b2ad5531db11e51de7b2d188c42d95576a/nimterop/toast --compile=./vendor/util/bloom.cc --compile=./vendor/util/arena.cc --compile=./vendor/util/env.cc --compile=./vendor/util/filter_policy.cc --compile=./vendor/util/histogram.cc --compile=./vendor/util/hash.cc --compile=./vendor/util/comparator.cc --compile=./vendor/util/options.cc --compile=./vendor/util/logging.cc --compile=./vendor/util/status.cc --compile=./vendor/util/coding.cc --compile=./vendor/util/cache.cc --compile=./vendor/util/crc32c.cc --compile=./vendor/table/table.cc --compile=./vendor/table/format.cc --compile=./vendor/table/table_builder.cc --compile=./vendor/table/block_builder.cc --compile=./vendor/table/merger.cc --compile=./vendor/table/block.cc --compile=./vendor/table/filter_block.cc --compile=./vendor/table/iterator.cc --compile=./vendor/table/two_level_iterator.cc --compile=./vendor/helpers/memenv/memenv.cc --compile=./vendor/db/filename.cc --compile=./vendor/db/dbformat.cc --compile=./vendor/db/c.cc --compile=./vendor/db/memtable.cc --compile=./vendor/db/version_set.cc --compile=./vendor/db/repair.cc --compile=./vendor/db/builder.cc --compile=./vendor/db/write_batch.cc --compile=./vendor/db/version_edit.cc --compile=./vendor/db/dumpfile.cc --compile=./vendor/db/db_impl.cc --compile=./vendor/db/log_reader.cc --compile=./vendor/db/table_cache.cc --compile=./vendor/db/db_iter.cc --compile=./vendor/db/log_writer.cc --pnim --preprocess --noHeader --includeDirs=./vendor --includeDirs=./vendor/helpers --includeDirs=./vendor/helpers/memenv --includeDirs=./vendor/port --includeDirs=./vendor/include ./vendor/include/leveldb/c.h
 
 {.push hint[ConvFromXtoItselfNotNeeded]: off.}
 import macros
@@ -79,45 +107,44 @@ macro defineEnum(typ: untyped): untyped =
 {.passc: "-I" & root & "/vendor/helpers/memenv".}
 {.passc: "-I" & root & "/vendor/port".}
 {.passc: "-I" & root & "/vendor/include".}
-{.passc: "-I" & root & "/build/include".}
+{.compile: root & "/vendor/util/bloom.cc".}
-{.compile: root & "/vendor/db/log_writer.cc".}
+{.compile: root & "/vendor/util/arena.cc".}
-{.compile: root & "/vendor/db/db_impl.cc".}
+{.compile: root & "/vendor/util/env.cc".}
-{.compile: root & "/vendor/db/db_iter.cc".}
+{.compile: root & "/vendor/util/filter_policy.cc".}
-{.compile: root & "/vendor/db/dumpfile.cc".}
+{.compile: root & "/vendor/util/histogram.cc".}
-{.compile: root & "/vendor/db/c.cc".}
+{.compile: root & "/vendor/util/hash.cc".}
-{.compile: root & "/vendor/db/builder.cc".}
+{.compile: root & "/vendor/util/comparator.cc".}
+{.compile: root & "/vendor/util/options.cc".}
+{.compile: root & "/vendor/util/logging.cc".}
+{.compile: root & "/vendor/util/status.cc".}
+{.compile: root & "/vendor/util/coding.cc".}
+{.compile: root & "/vendor/util/cache.cc".}
+{.compile: root & "/vendor/util/crc32c.cc".}
+{.compile: root & "/vendor/table/table.cc".}
+{.compile: root & "/vendor/table/format.cc".}
+{.compile: root & "/vendor/table/table_builder.cc".}
+{.compile: root & "/vendor/table/block_builder.cc".}
+{.compile: root & "/vendor/table/merger.cc".}
+{.compile: root & "/vendor/table/block.cc".}
+{.compile: root & "/vendor/table/filter_block.cc".}
+{.compile: root & "/vendor/table/iterator.cc".}
+{.compile: root & "/vendor/table/two_level_iterator.cc".}
+{.compile: root & "/vendor/helpers/memenv/memenv.cc".}
 {.compile: root & "/vendor/db/filename.cc".}
-{.compile: root & "/vendor/db/write_batch.cc".}
-{.compile: root & "/vendor/db/table_cache.cc".}
-{.compile: root & "/vendor/db/version_edit.cc".}
 {.compile: root & "/vendor/db/dbformat.cc".}
-{.compile: root & "/vendor/db/log_reader.cc".}
+{.compile: root & "/vendor/db/c.cc".}
 {.compile: root & "/vendor/db/memtable.cc".}
 {.compile: root & "/vendor/db/version_set.cc".}
 {.compile: root & "/vendor/db/repair.cc".}
-{.compile: root & "/vendor/table/block.cc".}
+{.compile: root & "/vendor/db/builder.cc".}
-{.compile: root & "/vendor/table/two_level_iterator.cc".}
+{.compile: root & "/vendor/db/write_batch.cc".}
-{.compile: root & "/vendor/table/table_builder.cc".}
+{.compile: root & "/vendor/db/version_edit.cc".}
-{.compile: root & "/vendor/table/iterator.cc".}
+{.compile: root & "/vendor/db/dumpfile.cc".}
-{.compile: root & "/vendor/table/block_builder.cc".}
+{.compile: root & "/vendor/db/db_impl.cc".}
-{.compile: root & "/vendor/table/merger.cc".}
+{.compile: root & "/vendor/db/log_reader.cc".}
-{.compile: root & "/vendor/table/format.cc".}
+{.compile: root & "/vendor/db/table_cache.cc".}
-{.compile: root & "/vendor/table/filter_block.cc".}
+{.compile: root & "/vendor/db/db_iter.cc".}
-{.compile: root & "/vendor/table/table.cc".}
+{.compile: root & "/vendor/db/log_writer.cc".}
-{.compile: root & "/vendor/util/hash.cc".}
-{.compile: root & "/vendor/util/arena.cc".}
-{.compile: root & "/vendor/util/options.cc".}
-{.compile: root & "/vendor/util/histogram.cc".}
-{.compile: root & "/vendor/util/crc32c.cc".}
-{.compile: root & "/vendor/util/env.cc".}
-{.compile: root & "/vendor/util/filter_policy.cc".}
-{.compile: root & "/vendor/util/bloom.cc".}
-{.compile: root & "/vendor/util/logging.cc".}
-{.compile: root & "/vendor/util/coding.cc".}
-{.compile: root & "/vendor/util/status.cc".}
-{.compile: root & "/vendor/util/cache.cc".}
-{.compile: root & "/vendor/util/comparator.cc".}
-{.compile: root & "/vendor/helpers/memenv/memenv.cc".}
 defineEnum(Enum_ch1)
 const
   leveldb_no_compression* = (0).cint

tests/test.nim

@@ -21,7 +21,10 @@ proc execNimble(args: varargs[string]): tuple[output: string, exitCode: int] =
   quotedArgs.insert("-y")
   quotedArgs.insert("--nimbleDir:" & tmpNimbleDir)
   quotedArgs.insert("nimble")
-  quotedArgs = quotedArgs.map(proc (x: string): string = "\"" & x & "\"")
+  quotedArgs = quotedArgs.map(
+    proc(x: string): string =
+      "\"" & x & "\""
+  )
 
   let cmd = quotedArgs.join(" ")
   result = execCmdEx(cmd)
@@ -33,7 +36,10 @@ proc execTool(args: varargs[string]): tuple[output: string, exitCode: int] =
   quotedArgs.insert(tmpDbDir)
   quotedArgs.insert("--database")
   quotedArgs.insert(findExe(tmpNimbleDir / "bin" / "leveldbtool"))
-  quotedArgs = quotedArgs.map(proc (x: string): string = "\"" & x & "\"")
+  quotedArgs = quotedArgs.map(
+    proc(x: string): string =
+      "\"" & x & "\""
+  )
 
   if not dirExists(tmpDbDir):
     createDir(tmpDbDir)
@@ -44,7 +50,6 @@ proc execTool(args: varargs[string]): tuple[output: string, exitCode: int] =
   checkpoint(result.output)
 
 suite "leveldb":
-
   setup:
     let env = leveldb_create_default_env()
     let dbName = $(leveldb_env_get_test_directory(env))
@@ -97,33 +102,27 @@ suite "leveldb":
 
   test "iter reverse":
     initData(db)
-    check(toSeq(db.iter(reverse = true)) ==
+    check(toSeq(db.iter(reverse = true)) == @[("bb", "3"), ("ba", "2"), ("aa", "1")])
-          @[("bb", "3"), ("ba", "2"), ("aa", "1")])
 
   test "iter seek":
     initData(db)
-    check(toSeq(db.iter(seek = "ab")) ==
+    check(toSeq(db.iter(seek = "ab")) == @[("ba", "2"), ("bb", "3")])
-          @[("ba", "2"), ("bb", "3")])
 
   test "iter seek reverse":
     initData(db)
-    check(toSeq(db.iter(seek = "ab", reverse = true)) ==
+    check(toSeq(db.iter(seek = "ab", reverse = true)) == @[("ba", "2"), ("aa", "1")])
-          @[("ba", "2"), ("aa", "1")])
 
   test "iter prefix":
     initData(db)
-    check(toSeq(db.iterPrefix(prefix = "b")) ==
+    check(toSeq(db.iterPrefix(prefix = "b")) == @[("ba", "2"), ("bb", "3")])
-          @[("ba", "2"), ("bb", "3")])
 
   test "iter range":
     initData(db)
-    check(toSeq(db.iterRange(start = "a", limit = "ba")) ==
+    check(toSeq(db.iterRange(start = "a", limit = "ba")) == @[("aa", "1"), ("ba", "2")])
-          @[("aa", "1"), ("ba", "2")])
 
   test "iter range reverse":
     initData(db)
-    check(toSeq(db.iterRange(start = "bb", limit = "b")) ==
+    check(toSeq(db.iterRange(start = "bb", limit = "b")) == @[("bb", "3"), ("ba", "2")])
-          @[("bb", "3"), ("ba", "2")])
 
   test "iter with 0x00":
     db.put("\0z1", "\0ff")
@@ -201,21 +200,265 @@ suite "leveldb":
   test "no compress":
     db.close()
     let nc = leveldb.open(dbName, compressionType = ctNoCompression)
-    defer: nc.close()
+    defer:
+      nc.close()
     nc.put("a", "1")
     check(toSeq(nc.iter()) == @[("a", "1")])
 
-suite "package":
+suite "leveldb queryIter":
+  setup:
+    let env = leveldb_create_default_env()
+    let dbName = $(leveldb_env_get_test_directory(env))
+    let db = leveldb.open(dbName)
+    let
+      k1 = "k1"
+      k2 = "k2"
+      k3 = "l3"
+      v1 = "v1"
+      v2 = "v2"
+      v3 = "v3"
+      empty = ("", "")
 
+    db.put(k1, v1)
+    db.put(k2, v2)
+    db.put(k3, v3)
+
+  teardown:
+    db.close()
+    removeDb(dbName)
+
+  test "iterates all keys and values":
+    let iter = db.queryIter()
+    check:
+      not iter.finished
+      iter.next() == (k1, v1)
+      not iter.finished
+      iter.next() == (k2, v2)
+      not iter.finished
+      iter.next() == (k3, v3)
+      not iter.finished
+      iter.next() == empty
+      iter.finished
+
+  test "iterate until disposed":
+    let iter = db.queryIter()
+    check:
+      not iter.finished
+      iter.next() == (k1, v1)
+      not iter.finished
+      iter.next() == (k2, v2)
+      not iter.finished
+
+    iter.dispose()
+
+    check:
+      iter.finished
+      iter.next() == empty
+      iter.finished
+
+  test "skip":
+    let iter = db.queryIter(skip = 1)
+    check:
+      not iter.finished
+      iter.next() == (k2, v2)
+      not iter.finished
+      iter.next() == (k3, v3)
+      not iter.finished
+      iter.next() == empty
+      iter.finished
+
+  test "limit":
+    let iter = db.queryIter(limit = 2)
+    check:
+      not iter.finished
+      iter.next() == (k1, v1)
+      not iter.finished
+      iter.next() == (k2, v2)
+      not iter.finished
+      iter.next() == empty
+      iter.finished
+
+  test "iterates only keys":
+    let iter = db.queryIter(keysOnly = true)
+    check:
+      not iter.finished
+      iter.next() == (k1, "")
+      not iter.finished
+      iter.next() == (k2, "")
+      not iter.finished
+      iter.next() == (k3, "")
+      not iter.finished
+      iter.next() == empty
+      iter.finished
+
+  test "iterates only 'k', both keys and values":
+    let iter = db.queryIter(prefix = "k")
+    check:
+      not iter.finished
+      iter.next() == (k1, v1)
+      not iter.finished
+      iter.next() == (k2, v2)
+      not iter.finished
+      iter.next() == empty
+      iter.finished
+
+  test "iterates only 'k', skip":
+    let iter = db.queryIter(prefix = "k", skip = 1)
+    check:
+      not iter.finished
+      iter.next() == (k2, v2)
+      not iter.finished
+      iter.next() == empty
+      iter.finished
+
+  test "iterate only 'k', limit":
+    let iter = db.queryIter(prefix = "k", limit = 1)
+    check:
+      not iter.finished
+      iter.next() == (k1, v1)
+      not iter.finished
+      iter.next() == empty
+      iter.finished
+
+  test "iterates only 'k', only keys":
+    let iter = db.queryIter(prefix = "k", keysOnly = true)
+    check:
+      not iter.finished
+      iter.next() == (k1, "")
+      not iter.finished
+      iter.next() == (k2, "")
+      not iter.finished
+      iter.next() == empty
+      iter.finished
+
+  test "concurrent iterators - 1":
+    let
+      iter1 = db.queryIter()
+      iter2 = db.queryIter()
+
+    check:
+      # 1, then 2
+      not iter1.finished
+      iter1.next() == (k1, v1)
+
+      not iter2.finished
+      iter2.next() == (k1, v1)
+
+      # 1, 1, then 2, 2
+      not iter1.finished
+      iter1.next() == (k2, v2)
+      not iter1.finished
+      iter1.next() == (k3, v3)
+
+      not iter2.finished
+      iter2.next() == (k2, v2)
+      not iter2.finished
+      iter2.next() == (k3, v3)
+
+      # finish 1, then finish 2
+      not iter1.finished
+      iter1.next() == empty
+
+      not iter2.finished
+      iter2.next() == empty
+
+      iter1.finished
+      iter2.finished
+
+  test "concurrent iterators - 2":
+    let
+      iter1 = db.queryIter()
+      iter2 = db.queryIter()
+
+    check:
+      # 1, then 2
+      not iter1.finished
+      iter1.next() == (k1, v1)
+
+      not iter2.finished
+      iter2.next() == (k1, v1)
+
+      # finish 1
+      not iter1.finished
+      iter1.next() == (k2, v2)
+      not iter1.finished
+      iter1.next() == (k3, v3)
+      not iter1.finished
+      iter1.next() == empty
+      iter1.finished
+
+      # finish 2
+      not iter2.finished
+      iter2.next() == (k2, v2)
+      not iter2.finished
+      iter2.next() == (k3, v3)
+      not iter2.finished
+      iter2.next() == empty
+      iter2.finished
+
+  test "concurrent iterators - dispose":
+    let
+      iter1 = db.queryIter()
+      iter2 = db.queryIter()
+
+    check:
+      # 1, then 2
+      not iter1.finished
+      iter1.next() == (k1, v1)
+
+      not iter2.finished
+      iter2.next() == (k1, v1)
+
+    # dispose 1
+    iter1.dispose()
+
+    check:
+      iter1.finished
+      iter1.next() == empty
+      iter1.finished
+
+      # finish 2
+      not iter2.finished
+      iter2.next() == (k2, v2)
+      not iter2.finished
+      iter2.next() == (k3, v3)
+      not iter2.finished
+      iter2.next() == empty
+      iter2.finished
+
+  test "modify while iterating":
+    let iter = db.queryIter()
+
+    check:
+      not iter.finished
+      iter.next() == (k1, v1)
+      not iter.finished
+      iter.next() == (k2, v2)
+
+    # insert
+    let
+      k4 = "k4"
+      v4 = "v4"
+    db.put(k4, v4)
+
+    check:
+      not iter.finished
+      iter.next() == (k3, v3)
+      not iter.finished
+      iter.next() == empty
+      iter.finished
+
+suite "package":
   setup:
     removeDir(tmpDir)
 
   test "import as package":
     let (output, exitCode) = execNimble("install")
     check exitCode == QuitSuccess
-    check output.contains("leveldbstatic installed successfully.")
+    check output.contains("leveldbstatic installed successfully.") or
+      output.contains("LevelDB already build")
 
-    cd "tests"/"packagetest":
+    cd "tests" / "packagetest":
       var (output, exitCode) = execNimble("build")
       check exitCode == QuitSuccess
       check output.contains("Building")
@@ -226,7 +469,6 @@ suite "package":
       check output.contains("leveldb works.")
 
 suite "tool":
-
   setup:
     removeDir(tmpDir)