Remove DOTALL flag from parse_wp_config() regexes

[pwtyler]

Summary

Fixes #63 — concatenation expressions like $x = 'foo' . $bar; caused parse_wp_config() to match across statement boundaries, making exists(), get_value(), and other methods fail to find entries that followed.

Root cause

The old quoted-string patterns ('.*?[^\\]' / ".*?[^\\]") with the /s (DOTALL) flag could match from the opening quote of one statement all the way into a subsequent statement when the value wasn't a simple quoted string (e.g. contained concatenation operators).

How the regex works now

The value-matching portion of each regex uses three alternation branches, tried left to right:

1. Empty strings — '' or "" (literal empty values)
2. Quoted strings via unrolled loop — '[^'\\]*(?:\\[\s\S][^'\\]*)*' (and the double-quote equivalent)
   • [^'\\]* matches any run of characters that aren't a quote or backslash (including newlines — so multiline string values work)
   • (?:\\[\s\S][^'\\]*)* matches escape sequences: a backslash followed by any character (including newline), then another run of non-quote/non-backslash characters. Repeats zero or more times.
   • This pattern is self-terminating — it stops exactly at the closing quote and cannot cross statement boundaries, which is the key property that fixes the original bug.
3. Raw fallback — [\s\S]*? matches everything else (function calls, arrays, ternaries, concatenation expressions) lazily up to the closing ) or ;. Uses [\s\S] instead of . so multiline raw expressions (e.g. multi-line array defines) still match without the /s flag.

The /s (DOTALL) flag is removed entirely. Newline matching is handled explicitly: [\s\S] where needed, and [^'\\]/[^"\\] character classes which inherently match newlines.

What's tested

The ConcatenationTest covers:

• Concatenation expressions and entries after them (the original bug)
• Multiline string values and entries after them
• Multiline raw expressions (array defines, multi-line concatenation)
• Backslash-newline inside quoted strings
• get_value() correctness for all edge cases (captured value groups)
• update() on a multiline entry with post-update readback

[github-actions]

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[gemini-code-assist]

Code Review

This pull request modifies the regex patterns in WPConfigTransformer.php by removing the global /s (DOTALL) flag to prevent over-matching on complex expressions like string concatenations. It also adds a new test suite and fixture to verify the parsing of variables and constants in these cases. A review comment points out that this change causes a regression for string values containing literal newlines and suggests using inline (?s:...) flags within the quoted string segments to maintain support for multiline values without the global over-matching issue.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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[swissspidy]

Thanks for the PR! I'll take a closer look after the weekend.

[Copilot]

Pull request overview

This PR adjusts WPConfigTransformer::parse_wp_config() regex parsing to avoid consuming subsequent assignments when a value contains non-literal expressions (notably concatenation), and adds regression coverage for that scenario (Fixes #63).

Changes:

• Updated constant/variable matching regexes to remove the DOTALL (s) flag and replaced the quoted-string alternations with unrolled-loop patterns.
• Added a new wp-config fixture exercising concatenation and multiline string literals.
• Added a PHPUnit test validating exists()/get_value() behavior for variables/constants following concatenation and multiline strings, and updated PHPCS exclusions for the new fixture.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 4 comments.

File	Description
src/WPConfigTransformer.php	Updates regex parsing to avoid cross-statement consumption and improve quoted-string matching.
tests/fixtures/wp-config-concat.php	New fixture with concatenation and multiline string literal cases.
tests/ConcatenationTest.php	New regression tests ensuring later variables/constants are still discoverable.
phpcs.xml.dist	Excludes the new fixture from PHPCS scanning.

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[pwtyler]

@swissspidy, addressed Copilot's feedback with additional test cases included.

I am by no means a regex expert, so my confidence is mostly in trying to ID edge test cases— if there's anything else you might think to add as coverage let me know.