ci(run-tests): fix data JSON checker error reporting

Fixes a problem with the CI data JSON checker that was not reporting
proper error code when checking multiple files.

run-tests.sh

@@ -36,7 +36,7 @@ data_dois() {
 }
 
 data_json() {
-    find . -name "*.json" -exec ./scripts/clean_json_file.py --check {} \;
+    find . -name "*.json" -exec ./scripts/clean_json_file.py --check {} \+
 }
 
 data_licenses() {

scripts/clean_json_file.py

@@ -1,9 +1,10 @@
 #!/usr/bin/env python3
 
-"""Clean JSON file.
+"""
+Clean JSON files.
 
-Cleans JSON file so as to fix indentation, order fields, and remove trailing
-whitespace.
+Clean one or more JSON files so as to fix indentation, order fields, and remove
+trailing whitespace.
 """
 
 import json
@@ -13,46 +14,49 @@
 
 
 @click.command()
-@click.argument("filename", type=click.Path(exists=True))
+@click.argument(
+    "filenames", metavar="[FILENAME] ...", type=click.Path(exists=True), nargs=-1
+)
 @click.option(
     "--check",
     is_flag=True,
     default=False,
     help="Don't write the file back, only check whether the file is well formatted.",
 )
-def clean_json_file(filename, check):  # noqa: D301
-    """Clean JSON file.
-
-    Clean JSON file so as to fix indentation, order fields, and remove trailing
-    whitespace.
+def clean_json_file(filenames, check):  # noqa: D301
+    """
+    Clean JSON files.
 
-    \b
-    :param filename: The file name to be reformatted.
-    :param check: Do not modify file, only check whether it is well formatted.
-    :type filename: str
-    :type check: bool
+    Clean one or more JSON files so as to fix indentation, order fields, and
+    remove trailing whitespace.
     """
-    with open(filename, "r") as fdesc:
-        old_content = fdesc.read()
-        records = json.loads(old_content)
-        new_content = (
-            json.dumps(
-                records,
-                indent=2,
-                sort_keys=True,
-                ensure_ascii=False,
-                separators=(",", ": "),
+    problematic_files = []
+    for filename in list(set(filenames)):
+        with open(filename, "r") as fdesc:
+            old_content = fdesc.read()
+            records = json.loads(old_content)
+            new_content = (
+                json.dumps(
+                    records,
+                    indent=2,
+                    sort_keys=True,
+                    ensure_ascii=False,
+                    separators=(",", ": "),
+                )
+                + "\n"
             )
-            + "\n"
-        )
 
-    if old_content != new_content:
-        if check:
+        if old_content != new_content:
+            if check:
+                problematic_files.append(filename)
+            else:
+                with open(filename, "w") as fdesc:
+                    fdesc.write(new_content)
+
+    if check and problematic_files:
+        for filename in problematic_files:
             print(f"[ERROR] File {filename} is badly formatted.")
-            sys.exit(1)
-        else:
-            with open(filename, "w") as fdesc:
-                fdesc.write(new_content)
+        sys.exit(1)
 
 
 if __name__ == "__main__":