Removed todo notes

cpp/src/arrow/dataset/scanner.h

@@ -85,7 +85,6 @@ class ARROW_DS_EXPORT ScanTask {
   /// \brief Iterate through sequence of materialized record batches
   /// resulting from the Scan. Execution semantics are encapsulated in the
   /// particular ScanTask implementation
-  // TODO(kszucs): call it execute?
   virtual Result<RecordBatchIterator> Scan() = 0;
 
   virtual ~ScanTask() = default;

python/pyarrow/_dataset.pyx

@@ -59,7 +59,6 @@ cdef class FileFormat:
     cdef wrap(shared_ptr[CFileFormat]& sp):
         cdef FileFormat self
 
-        # TODO(kszucs): either choose type() or name() but consistently
         typ = frombytes(sp.get().name())
         if typ == 'parquet':
             self = ParquetFileFormat.__new__(ParquetFileFormat)
@@ -349,7 +348,6 @@ cdef class DataSource:
             return Expression.wrap(expression)
 
 
-# TODO(kszucs) Rename it to InMemoryDataSource
 cdef class SimpleDataSource(DataSource):
     """An in memory DataSource created from in memory RecordBatches"""
 
@@ -397,7 +395,7 @@ cdef class TreeDataSource(DataSource):
 
 
 cdef class FileSystemDataSource(DataSource):
-    """"""
+    """A DataSource created from a set of files on a particular filesystem"""
 
     cdef:
         CFileSystemDataSource* filesystem_source

python/pyarrow/_fs.pyx

@@ -194,7 +194,6 @@ cdef class FileSystem:
     cdef wrap(shared_ptr[CFileSystem]& sp):
         cdef FileSystem self
 
-        # TODO(kszucs): add S3
         typ = frombytes(sp.get().type())
         if typ == 'local':
             self = LocalFileSystem.__new__(LocalFileSystem)
@@ -202,6 +201,9 @@ cdef class FileSystem:
             self = _MockFileSystem.__new__(_MockFileSystem)
         elif typ == 'subtree':
             self = SubTreeFileSystem.__new__(SubTreeFileSystem)
+        elif typ == 's3':
+            from pyarrow.s3fs import S3FileSystem
+            self = S3FileSystem.__new__(S3FileSystem)
         else:
             raise TypeError('Cannot wrap FileSystem pointer')