[stdlib] implement os.path.getsize

Signed-off-by: Artemio Garza Reyna <artemiogr97@gmail.com>

docs/changelog.md

@@ -311,6 +311,9 @@ what we publish.
 - Added `atof()` function which can convert a `String` to a `float64`.
   ([PR #2649](https://github.com/modularml/mojo/pull/2649) by [@fknfilewalker](https://github.com/fknfilewalker))
 
+- Added `os.getsize` function, which gives the size in bytes of a path.
+  ([PR 2626](https://github.com/modularml/mojo/pull/2626) by [@artemiogr97](https://github.com/artemiogr97))
+
 ### 🦋 Changed
 
 - The `let` keyword has been completely removed from the language. We previously

stdlib/src/os/path/__init__.mojo

@@ -11,4 +11,4 @@
 # limitations under the License.
 # ===----------------------------------------------------------------------=== #
 
-from .path import exists, isdir, isfile, islink, lexists
+from .path import exists, isdir, isfile, islink, lexists, getsize

stdlib/src/os/path/path.mojo

@@ -29,6 +29,7 @@ from .._linux_x86 import _lstat as _lstat_linux_x86
 from .._linux_x86 import _stat as _stat_linux_x86
 from .._macos import _lstat as _lstat_macos
 from .._macos import _stat as _stat_macos
+from ..fstat import stat
 
 
 # ===----------------------------------------------------------------------=== #
@@ -250,3 +251,35 @@ fn lexists[pathlike: os.PathLike](path: pathlike) -> Bool:
       Returns True if the path exists or is a broken symbolic link.
     """
     return exists(path.__fspath__())
+
+
+# ===----------------------------------------------------------------------=== #
+# getsize
+# ===----------------------------------------------------------------------=== #
+
+
+fn getsize(path: String) raises -> Int:
+    """Return the size, in bytes, of the specified path.
+
+    Args:
+      path: The path to the file.
+
+    Returns:
+      The size of the path in bytes.
+    """
+    return stat(path).st_size
+
+
+fn getsize[pathlike: os.PathLike](path: pathlike) raises -> Int:
+    """Return the size, in bytes, of the specified path.
+
+    Parameters:
+      pathlike: The a type conforming to the os.PathLike trait.
+
+    Args:
+      path: The path to the file.
+
+    Returns:
+      The size of the path in bytes.
+    """
+    return getsize(path.__fspath__())

stdlib/test/os/path/test_getsize.mojo

@@ -0,0 +1,31 @@
+# ===----------------------------------------------------------------------=== #
+# Copyright (c) 2024, Modular Inc. All rights reserved.
+#
+# Licensed under the Apache License v2.0 with LLVM Exceptions:
+# https://llvm.org/LICENSE.txt
+#
+# 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.
+# ===----------------------------------------------------------------------=== #
+# RUN: %mojo %s
+
+import os
+from os.path import getsize
+from builtin._location import __source_location
+
+from testing import assert_equal, assert_false
+
+
+fn main() raises:
+    alias file_name = "test_file"
+    assert_false(os.path.exists(file_name), "File should not exist")
+    with open(file_name, "w"):
+        pass
+    assert_equal(getsize(file_name), 0)
+    with open(file_name, "w") as my_file:
+        my_file.write("test")
+    assert_equal(getsize(file_name), 4)
+    os.remove(file_name)