[PATCH] D64589: [UpdateTestChecks] Emit warning when invalid value for -check-prefix(es) option

[Greg Bedwell via Phabricator via llvm-commits]

gbedwell added a comment.

I've tried the latest update and it seems to work well for me.   The only suggestion I'd make at this stage is optionally adding a message like `(did you mean --check-prefixes?)` if a comma is spotted in the prefix string.

  --check-prefix=FOO,BAR

gives a fairly generic warning message now:

  WARNING: Supplied prefix 'FOO,BAR' is invalid. Prefix must start with a letter and contain only alphanumeric characters, hyphens and underscores.

which I can believe that if I was new to filecheck would probably cause me to spend more time debugging the issue than I'd like.



================
Comment at: utils/UpdateTestChecks/common.py:287
+        if prefixes.count(prefix) > 1:
+          print('WARNING: Supplied prefix \'%s\' is not unique in prefix list.' %
+                (prefix,), file=sys.stderr)
----------------
A very nitpicky and minor style nit, but you can contain single quotes in double quoted strings and double quotes in single quotes strings, so it may be more readable like this as you don't have to escape anything.


```
print('WARNING: Supplied prefix "%s" is not unique in prefix list.'
```

or:

```
print("WARNING: Supplied prefix '%s' is not unique in prefix list."
```



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  https://reviews.llvm.org/D64589/new/

https://reviews.llvm.org/D64589