[llvm] [Debugify] Add 'error-test' mode for the debugify report script, for CI (PR #147574)

[Djordje Todorovic via llvm-commits]

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@@ -430,9 +478,16 @@ def get_json_chunk(file, start, size):
 # Parse the program arguments.
 def parse_program_args(parser):
     parser.add_argument("file_name", type=str, help="json file to process")
-    parser.add_argument("html_file", type=str, help="html file to output data")
-    parser.add_argument(
-        "-compress", action="store_true", help="create reduced html report"
+    parser.add_argument("--compress", action="store_true", help="create reduced report")
+
+    report_type_group = parser.add_mutually_exclusive_group(required=True)
+    report_type_group.add_argument(
+        "--report-file", type=str, help="output HTML file for the generated report"
+    )
+    report_type_group.add_argument(
+        "--error-test",
+        action="store_true",
+        help="if set, produce terminal-friendly output and return 0 iff the input file is empty or does not exist",
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djtodoro wrote:

Okay, it does make sense.

https://github.com/llvm/llvm-project/pull/147574