Change occurrences of % and format() to f-strings

docs/release.rst

@@ -18,6 +18,9 @@ Release notes
 Unreleased
 ----------
 
+* Change occurrences of % and format() to f-strings.
+  By :user:`Dimitri Papadopoulos Orfanos <DimitriPapadopoulos>` :issue:`1423`.
+
 .. _release_2.17.0:
 
 2.17.0

zarr/_storage/absstore.py

@@ -84,7 +84,7 @@ def __init__(
 
             blob_service_kwargs = blob_service_kwargs or {}
             client = ContainerClient(
-                "https://{}.blob.core.windows.net/".format(account_name),
+                f"https://{account_name}.blob.core.windows.net/",
                 container,
                 credential=account_key,
                 **blob_service_kwargs,
@@ -141,7 +141,7 @@ def __getitem__(self, key):
         try:
             return self.client.download_blob(blob_name).readall()
         except ResourceNotFoundError:
-            raise KeyError("Blob %s not found" % blob_name)
+            raise KeyError(f"Blob {blob_name} not found")
 
     def __setitem__(self, key, value):
         value = ensure_bytes(value)
@@ -154,7 +154,7 @@ def __delitem__(self, key):
         try:
             self.client.delete_blob(self._append_path_to_prefix(key))
         except ResourceNotFoundError:
-            raise KeyError("Blob %s not found" % key)
+            raise KeyError(f"Blob {key} not found")
 
     def __eq__(self, other):
         return (

zarr/_storage/store.py

@@ -227,7 +227,7 @@ def _validate_key(self, key: str):
             # TODO: Possibly allow key == ".zmetadata" too if we write a
             #       consolidated metadata spec corresponding to this?
         ):
-            raise ValueError("keys starts with unexpected value: `{}`".format(key))
+            raise ValueError(f"key starts with unexpected value: `{key}`")
 
         if key.endswith("/"):
             raise ValueError("keys may not end in /")

zarr/_storage/v3.py

@@ -569,7 +569,7 @@ def __init__(self, store: StoreLike, metadata_key=meta_root + "consolidated/.zme
         consolidated_format = meta.get("zarr_consolidated_format", None)
         if consolidated_format != 1:
             raise MetadataError(
-                "unsupported zarr consolidated metadata format: %s" % consolidated_format
+                f"unsupported zarr consolidated metadata format: {consolidated_format}"
             )
 
         # decode metadata

zarr/convenience.py

@@ -259,7 +259,7 @@ def save_group(store: StoreLike, *args, zarr_version=None, path=None, **kwargs):
     try:
         grp = _create_group(_store, path=path, overwrite=True, zarr_version=zarr_version)
         for i, arr in enumerate(args):
-            k = "arr_{}".format(i)
+            k = f"arr_{i}"
             grp.create_dataset(k, data=arr, overwrite=True, zarr_version=zarr_version)
         for k, arr in kwargs.items():
             grp.create_dataset(k, data=arr, overwrite=True, zarr_version=zarr_version)
@@ -499,7 +499,7 @@ def __init__(self, log):
             self.log_file = log
         else:
             raise TypeError(
-                "log must be a callable function, file path or " "file-like object, found %r" % log
+                f"log must be a callable function, file path or file-like object, found {log!r}"
             )
 
     def __enter__(self):
@@ -526,9 +526,9 @@ def _log_copy_summary(log, dry_run, n_copied, n_skipped, n_bytes_copied):
         message = "dry run: "
     else:
         message = "all done: "
-    message += "{:,} copied, {:,} skipped".format(n_copied, n_skipped)
+    message += f"{n_copied:,} copied, {n_skipped:,} skipped"
     if not dry_run:
-        message += ", {:,} bytes copied".format(n_bytes_copied)
+        message += f", {n_bytes_copied:,} bytes copied"
     log(message)
 
 
@@ -657,9 +657,7 @@ def copy_store(
     # check if_exists parameter
     valid_if_exists = ["raise", "replace", "skip"]
     if if_exists not in valid_if_exists:
-        raise ValueError(
-            "if_exists must be one of {!r}; found {!r}".format(valid_if_exists, if_exists)
-        )
+        raise ValueError(f"if_exists must be one of {valid_if_exists!r}; found {if_exists!r}")
 
     # setup counting variables
     n_copied = n_skipped = n_bytes_copied = 0
@@ -720,20 +718,20 @@ def copy_store(
             if if_exists != "replace":
                 if dest_key in dest:
                     if if_exists == "raise":
-                        raise CopyError("key {!r} exists in destination".format(dest_key))
+                        raise CopyError(f"key {dest_key!r} exists in destination")
                     elif if_exists == "skip":
                         do_copy = False
 
             # take action
             if do_copy:
-                log("copy {}".format(descr))
+                log(f"copy {descr}")
                 if not dry_run:
                     data = source[source_key]
                     n_bytes_copied += buffer_size(data)
                     dest[dest_key] = data
                 n_copied += 1
             else:
-                log("skip {}".format(descr))
+                log(f"skip {descr}")
                 n_skipped += 1
 
         # log a final message with a summary of what happened
@@ -744,7 +742,7 @@ def copy_store(
 
 def _check_dest_is_group(dest):
     if not hasattr(dest, "create_dataset"):
-        raise ValueError("dest must be a group, got {!r}".format(dest))
+        raise ValueError(f"dest must be a group, got {dest!r}")
 
 
 def copy(
@@ -910,11 +908,9 @@ def _copy(log, source, dest, name, root, shallow, without_attrs, if_exists, dry_
     # check if_exists parameter
     valid_if_exists = ["raise", "replace", "skip", "skip_initialized"]
     if if_exists not in valid_if_exists:
-        raise ValueError(
-            "if_exists must be one of {!r}; found {!r}".format(valid_if_exists, if_exists)
-        )
+        raise ValueError(f"if_exists must be one of {valid_if_exists!r}; found {if_exists!r}")
     if dest_h5py and if_exists == "skip_initialized":
-        raise ValueError("{!r} can only be used when copying to zarr".format(if_exists))
+        raise ValueError(f"{if_exists!r} can only be used when copying to zarr")
 
     # determine name to copy to
     if name is None:
@@ -934,9 +930,7 @@ def _copy(log, source, dest, name, root, shallow, without_attrs, if_exists, dry_
         exists = dest is not None and name in dest
         if exists:
             if if_exists == "raise":
-                raise CopyError(
-                    "an object {!r} already exists in destination " "{!r}".format(name, dest.name)
-                )
+                raise CopyError(f"an object {name!r} already exists in destination {dest.name!r}")
             elif if_exists == "skip":
                 do_copy = False
             elif if_exists == "skip_initialized":
@@ -947,7 +941,7 @@ def _copy(log, source, dest, name, root, shallow, without_attrs, if_exists, dry_
         # take action
         if do_copy:
             # log a message about what we're going to do
-            log("copy {} {} {}".format(source.name, source.shape, source.dtype))
+            log(f"copy {source.name} {source.shape} {source.dtype}")
 
             if not dry_run:
                 # clear the way
@@ -1015,7 +1009,7 @@ def _copy(log, source, dest, name, root, shallow, without_attrs, if_exists, dry_
             n_copied += 1
 
         else:
-            log("skip {} {} {}".format(source.name, source.shape, source.dtype))
+            log(f"skip {source.name} {source.shape} {source.dtype}")
             n_skipped += 1
 
     elif root or not shallow:
@@ -1026,16 +1020,14 @@ def _copy(log, source, dest, name, root, shallow, without_attrs, if_exists, dry_
         exists_array = dest is not None and name in dest and hasattr(dest[name], "shape")
         if exists_array:
             if if_exists == "raise":
-                raise CopyError(
-                    "an array {!r} already exists in destination " "{!r}".format(name, dest.name)
-                )
+                raise CopyError(f"an array {name!r} already exists in destination {dest.name!r}")
             elif if_exists == "skip":
                 do_copy = False
 
         # take action
         if do_copy:
             # log action
-            log("copy {}".format(source.name))
+            log(f"copy {source.name}")
 
             if not dry_run:
                 # clear the way
@@ -1078,7 +1070,7 @@ def _copy(log, source, dest, name, root, shallow, without_attrs, if_exists, dry_
             n_copied += 1
 
         else:
-            log("skip {}".format(source.name))
+            log(f"skip {source.name}")
             n_skipped += 1
 
     return n_copied, n_skipped, n_bytes_copied
@@ -1327,7 +1319,7 @@ def open_consolidated(store: StoreLike, metadata_key=".zmetadata", mode="r+", **
         store, storage_options=kwargs.get("storage_options"), mode=mode, zarr_version=zarr_version
     )
     if mode not in {"r", "r+"}:
-        raise ValueError("invalid mode, expected either 'r' or 'r+'; found {!r}".format(mode))
+        raise ValueError(f"invalid mode, expected either 'r' or 'r+'; found {mode!r}")
 
     path = kwargs.pop("path", None)
     if store._store_version == 2:

zarr/core.py

@@ -2396,11 +2396,11 @@ def _encode_chunk(self, chunk):
 
     def __repr__(self):
         t = type(self)
-        r = "<{}.{}".format(t.__module__, t.__name__)
+        r = f"<{t.__module__}.{t.__name__}"
         if self.name:
-            r += " %r" % self.name
-        r += " %s" % str(self.shape)
-        r += " %s" % self.dtype
+            r += f" {self.name!r}"
+        r += f" {str(self.shape)}"
+        r += f" {self.dtype}"
         if self._read_only:
             r += " read-only"
         r += ">"
@@ -2436,11 +2436,11 @@ def info_items(self):
 
     def _info_items_nosync(self):
         def typestr(o):
-            return "{}.{}".format(type(o).__module__, type(o).__name__)
+            return f"{type(o).__module__}.{type(o).__name__}"
 
         def bytestr(n):
             if n > 2**10:
-                return "{} ({})".format(n, human_readable_size(n))
+                return f"{n} ({human_readable_size(n)})"
             else:
                 return str(n)
 
@@ -2451,7 +2451,7 @@ def bytestr(n):
             items += [("Name", self.name)]
         items += [
             ("Type", typestr(self)),
-            ("Data type", "%s" % self.dtype),
+            ("Data type", str(self.dtype)),
             ("Shape", str(self.shape)),
             ("Chunk shape", str(self.chunks)),
             ("Order", self.order),
@@ -2461,7 +2461,7 @@ def bytestr(n):
         # filters
         if self.filters:
             for i, f in enumerate(self.filters):
-                items += [("Filter [%s]" % i, repr(f))]
+                items += [(f"Filter [{i}]", repr(f))]
 
         # compressor
         items += [("Compressor", repr(self.compressor))]
@@ -2478,9 +2478,9 @@ def bytestr(n):
         if self.nbytes_stored > 0:
             items += [
                 ("No. bytes stored", bytestr(self.nbytes_stored)),
-                ("Storage ratio", "%.1f" % (self.nbytes / self.nbytes_stored)),
+                ("Storage ratio", f"{self.nbytes / self.nbytes_stored:.1f}"),
             ]
-        items += [("Chunks initialized", "{}/{}".format(self.nchunks_initialized, self.nchunks))]
+        items += [("Chunks initialized", f"{self.nchunks_initialized}/{self.nchunks}")]
 
         return items
 

zarr/creation.py

@@ -287,7 +287,7 @@ def _kwargs_compat(compressor, fill_value, kwargs):
             compressor = compression
 
         else:
-            raise ValueError("bad value for compression: %r" % compression)
+            raise ValueError(f"bad value for compression: {compression!r}")
 
     # handle 'fillvalue'
     if "fillvalue" in kwargs:
@@ -297,7 +297,7 @@ def _kwargs_compat(compressor, fill_value, kwargs):
 
     # ignore other keyword arguments
     for k in kwargs:
-        warn("ignoring keyword argument %r" % k)
+        warn(f"ignoring keyword argument {k!r}")
 
     return compressor, fill_value
 

zarr/errors.py

@@ -67,9 +67,7 @@ def __init__(self):
 
 
 def err_too_many_indices(selection, shape):
-    raise IndexError(
-        "too many indices for array; expected {}, got {}".format(len(shape), len(selection))
-    )
+    raise IndexError(f"too many indices for array; expected {len(shape)}, got {len(selection)}")
 
 
 class VindexInvalidSelectionError(_BaseZarrIndexError):

zarr/hierarchy.py

@@ -340,9 +340,9 @@ def __len__(self):
 
     def __repr__(self):
         t = type(self)
-        r = "<{}.{}".format(t.__module__, t.__name__)
+        r = f"<{t.__module__}.{t.__name__}"
         if self.name:
-            r += " %r" % self.name
+            r += f" {self.name!r}"
         if self._read_only:
             r += " read-only"
         r += ">"
@@ -358,7 +358,7 @@ def __exit__(self, exc_type, exc_val, exc_tb):
 
     def info_items(self):
         def typestr(o):
-            return "{}.{}".format(type(o).__module__, type(o).__name__)
+            return f"{type(o).__module__}.{type(o).__name__}"
 
         items = []
 
@@ -1157,17 +1157,15 @@ def _require_dataset_nosync(self, name, shape, dtype=None, exact=False, **kwargs
             shape = normalize_shape(shape)
             if shape != a.shape:
                 raise TypeError(
-                    "shape do not match existing array; expected {}, got {}".format(a.shape, shape)
+                    f"shape do not match existing array; expected {a.shape}, got {shape}"
                 )
             dtype = np.dtype(dtype)
             if exact:
                 if dtype != a.dtype:
-                    raise TypeError(
-                        "dtypes do not match exactly; expected {}, got {}".format(a.dtype, dtype)
-                    )
+                    raise TypeError(f"dtypes do not match exactly; expected {a.dtype}, got {dtype}")
             else:
                 if not np.can_cast(dtype, a.dtype):
-                    raise TypeError("dtypes ({}, {}) cannot be safely cast".format(dtype, a.dtype))
+                    raise TypeError(f"dtypes ({dtype}, {a.dtype}) cannot be safely cast")
             return a
 
         else: