Allow for user controlled or raw regular expression

[emanlove]

The current implementation of the REGEX: match automatically prepend with ^ and postpend $ matching the entire message. This default is good because it reads without needing these symbols. But in some case when we want to use an inline modifier or flag then this throws an exception under Python 3.11 or greater. (Might be an earlier version but my search show this to have changed from a warning to an error with 3.11). Reason is that inline modifiers must be at the beginning of the expression. But with the behind the scenes addition of ^. this prevents this from happening with REGEX:.

To resolve while still keeping the existing usage I was proposing a new match called RAWRE (or RAWREGX or RAWREGEX or the like), for "raw regular expression", which will not include the prepended ^ and postpended $.

Attached is a sample test demonstrating the problem and a proposed solution. In addition to removing the prepend and postpended flags I also removed the re.DOTALL flag allowing the user to use rawre to use whichever flags they choose.

leading_global_flag_error.patch

diff --git a/test/tests.robot b/test/tests.robot
index 35b3fa1..3587a03 100644
--- a/test/tests.robot
+++ b/test/tests.robot
@@ -271,6 +271,7 @@ Expected PASS and log messages with COUNT
     ...    PASS Told ya!!
     ...    LOG 4 COUNT: 2
     ...    LOG 4:2 NONE
+    ...    LOG 3 INFO REGEXP: (?i)Any.*now\.\.\.
     Status    PASS    Told ya!!
     Log    Passing soon!
     Log    Any time now...

raw_re_solution.patch

diff --git a/robotstatuschecker.py b/robotstatuschecker.py
index 2f6acde..5091f9b 100755
--- a/robotstatuschecker.py
+++ b/robotstatuschecker.py
@@ -167,6 +167,10 @@ class BaseChecker:
             pattern = f"^{expected.replace('REGEXP:', '', 1).strip()}$"
             if re.match(pattern, actual, re.DOTALL):
                 return True
+        if expected.startswith("RAWRE:"):
+            pattern = f"{expected.replace('RAWRE:', '', 1).strip()}"
+            if re.match(pattern, actual):
+                return True
         if expected.startswith("GLOB:"):
             pattern = expected.replace("GLOB:", "", 1).strip()
             matcher = Matcher(pattern, caseless=False, spaceless=False)

test_solution.patch

diff --git a/test/tests.robot b/test/tests.robot
index 35b3fa1..21ff448 100644
--- a/test/tests.robot
+++ b/test/tests.robot
@@ -271,6 +271,7 @@ Expected PASS and log messages with COUNT
     ...    PASS Told ya!!
     ...    LOG 4 COUNT: 2
     ...    LOG 4:2 NONE
+    ...    LOG 3 INFO RAWRE: (?si)^Any.*now\.\.\.$
     Status    PASS    Told ya!!
     Log    Passing soon!
     Log    Any time now...

[pekkaklarck]

I'd prefer flags being supported by default. I believe it would be enough to just use newish re.fullmatch and omit ^$ altogether.

[pekkaklarck]

The offending ^ could actually be removed also with re.match, but re.fullmatch would be more explicit.

I don't see cases where the DOTALL mode would cause issues so I'd leave it. I wouldn't add a separate mode to allow disabling it either.

[pekkaklarck]

Notice that although inline flags were supposed to be used in the beginning if the pattern, they were actually supported also elsewhere until Python 3.11. For example, ^(?i)xxx$ worked earlier, but with 3.11+ needs to be written like (?i)^xxx$. In most of the cases, such as in ours, this particular case is easiest to fix by removing ^ and using re.match or re.fullmatch.

[emanlove]

I'm a bit out of my comfort zone and knowledge expertise when it comes to re design and architecture. The one thing I did really like and wanted to keep was that for regular expression one could just write the full expected message and not have to write out the match start and end. So if fullmatch works like that, which I was assuming it did, then I am good with your suggestions.