feat: add fs_sync package

Author: Young-Flash

fs_sync/blackbox_test.mbt

@@ -0,0 +1,27 @@
+// Copyright 2025 International Digital Economy Academy
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+test "write_and_read" {
+  let path_1 = "./fs_sync/test_1.txt"
+  let path_2 = "./fs_sync/test_2.txt"
+  let content_1 = "Hello, World"
+  let content_2 = "Hello, MoonBit"
+  @fs_sync.write_bytes_to_file!(path_1, content_1.to_bytes())
+  let res_1 = @fs_sync.read_file_to_bytes!(path_1)
+  inspect!(res_1.to_unchecked_string(), content=content_1)
+
+  @fs_sync.write_string_to_file!(path_2, content_2)
+  let res_2 = @fs_sync.read_file_to_string!(path_2)
+  inspect!(res_2, content=content_2)
+}

fs_sync/fs_sync.mbt

@@ -0,0 +1,66 @@
+// Copyright 2025 International Digital Economy Academy
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+///|
+pub type! IOError String derive(Show)
+
+///| Reads the content of a file specified by the given path and returns its
+/// content as `Bytes`
+///
+/// # Parameters
+///
+/// - `path` : The path to the file to be read.
+///
+/// # Returns
+///
+/// - A `Bytes` representing the content of the file.
+pub fn read_file_to_bytes(path: String) -> Bytes! {
+  read_file_to_bytes_internal!(path)
+}
+
+///| Reads the content of a file specified by the given path and returns its
+/// content as `String`.
+///
+/// # Parameters
+///
+/// - `path` : The path to the file to be read.
+/// - `encoding~` : The encoding of the file. Only support `utf8` for now.
+///
+/// # Returns
+///
+/// - A `String` representing the content of the file.
+pub fn read_file_to_string(path: String, encoding~ : String = "utf8") -> String! {
+  read_file_to_string_internal!(path, encoding~)
+}
+
+///| Writes a `Bytes` to a file at the specified path.
+///
+/// # Parameters
+///
+/// - `path` : The path to the file where the bytes will be written.
+/// - `content` : A `Bytes` to be written to the file.
+pub fn write_bytes_to_file(path: String, content: Bytes) -> Unit! {
+  write_bytes_to_file_internal!(path, content)
+}
+
+///| Writes a `String` to a file at the specified path.
+///
+/// # Parameters
+///
+/// - `path` : The path to the file where the string will be written.
+/// - `content` : A `String` to be written to the file.
+/// - `encoding~` : The encoding of the file. Only support `utf8` for now.
+pub fn write_string_to_file(path: String, content: String, encoding~ : String = "utf8") -> Unit! {
+  write_string_to_file_internal!(path, content, encoding~)
+}

fs_sync/fs_sync.mbti

@@ -0,0 +1,19 @@
+package moonbitlang/core/fs_sync
+
+// Values
+fn read_file_to_bytes(String) -> Bytes!
+
+fn read_file_to_string(String, encoding~ : String = ..) -> String!
+
+fn write_bytes_to_file(String, Bytes) -> Unit!
+
+fn write_string_to_file(String, String, encoding~ : String = ..) -> Unit!
+
+// Types and methods
+pub type! IOError String
+impl Show for IOError
+
+// Type aliases
+
+// Traits
+

fs_sync/moon.pkg.json

@@ -0,0 +1,18 @@
+{
+    "import": [
+        "moonbitlang/core/string",
+        "moonbitlang/core/builtin",
+        "moonbitlang/core/array",
+        "moonbitlang/core/bytes"
+    ],
+    "targets": {
+        "fs_sync_wasm.mbt": ["wasm", "wasm-gc"],
+        "fs_sync_js.mbt": ["js"],
+        "fs_sync_native.mbt": ["native"]
+    },
+    "link": {
+        "native": {
+           "cc-flags": "-O2"
+        }
+    }
+}

fs_sync/test_1.txt

@@ -0,0 +1 @@
+Hello, MoonBit

fs_sync/test_2.txt

@@ -0,0 +1,94 @@
+// Copyright 2025 International Digital Economy Academy
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+
+///|
+fn mbt_string_to_utf8_bytes(str : String, is_c_str : Bool) -> Bytes {
+  let res : Array[Byte] = []
+  let len = str.length()
+  let mut i = 0
+  while i < len {
+    let mut c = str[i].to_int()
+    if 0xD800 <= c && c <= 0xDBFF {
+      c -= 0xD800
+      i = i + 1
+      let l = str[i].to_int() - 0xDC00
+      c = (c << 10) + l + 0x10000
+    }
+
+    // stdout accepts UTF-8, so convert the stream to UTF-8 first
+    if c < 0x80 {
+      res.push(c.to_byte())
+    } else if c < 0x800 {
+      res.push((0xc0 + (c >> 6)).to_byte())
+      res.push((0x80 + (c & 0x3f)).to_byte())
+    } else if c < 0x10000 {
+      res.push((0xe0 + (c >> 12)).to_byte())
+      res.push((0x80 + ((c >> 6) & 0x3f)).to_byte())
+      res.push((0x80 + (c & 0x3f)).to_byte())
+    } else {
+      res.push((0xf0 + (c >> 18)).to_byte())
+      res.push((0x80 + ((c >> 12) & 0x3f)).to_byte())
+      res.push((0x80 + ((c >> 6) & 0x3f)).to_byte())
+      res.push((0x80 + (c & 0x3f)).to_byte())
+    }
+    i = i + 1
+  }
+  if is_c_str {
+    res.push((0).to_byte())
+  }
+  Bytes::from_array(res)
+}
+
+fn utf8_bytes_to_mbt_string(bytes : Bytes) -> String {
+  let res : Array[Char] = []
+  let len = bytes.length()
+  let mut i = 0
+  while i < len {
+    let mut c = bytes[i].to_int()
+    if c < 0x80 {
+      res.push(Char::from_int(c))
+      i += 1
+    } else if c < 0xE0 {
+      if i + 1 >= len {
+        break
+      }
+      c = ((c & 0x1F) << 6) | (bytes[i + 1].to_int() & 0x3F)
+      res.push(Char::from_int(c))
+      i += 2
+    } else if c < 0xF0 {
+      if i + 2 >= len {
+        break
+      }
+      c = ((c & 0x0F) << 12) |
+        ((bytes[i + 1].to_int() & 0x3F) << 6) |
+        (bytes[i + 2].to_int() & 0x3F)
+      res.push(Char::from_int(c))
+      i += 3
+    } else {
+      if i + 3 >= len {
+        break
+      }
+      c = ((c & 0x07) << 18) |
+        ((bytes[i + 1].to_int() & 0x3F) << 12) |
+        ((bytes[i + 2].to_int() & 0x3F) << 6) |
+        (bytes[i + 3].to_int() & 0x3F)
+      c -= 0x10000
+      res.push(Char::from_int((c >> 10) + 0xD800))
+      res.push(Char::from_int((c & 0x3FF) + 0xDC00))
+      i += 4
+    }
+  }
+  String::from_array(res)
+}