refactor(pcre): treat regex compile failure as fatal in shim

The preg_* shim helpers wrapped their results in Option/Result solely to
signal a regex that failed to compile. Composer never feeds a pattern
that fails at runtime, so such a failure is a programming error: panic
instead and drop the Option/Result wrappers, updating all callers.

preg_replace_callback keeps its Result return type since the callback
itself is fallible. preg_match_groups is removed in favor of preg_match
at its sole call site.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

1 files changed, 4 insertions, 7 deletions

diff --git a/crates/shirabe-semver/src/version_parser.rs b/crates/shirabe-semver/src/version_parser.rs
index bbd359e..bb4656c 100644
--- a/crates/shirabe-semver/src/version_parser.rs
+++ b/crates/shirabe-semver/src/version_parser.rs
@@ -25,7 +25,7 @@ pub struct VersionParser;
 
 impl VersionParser {
     pub fn parse_stability(version: &str) -> String {
-        let version = php::preg_replace("{#.+$}", "", version).unwrap_or_default();
+        let version = php::preg_replace("{#.+$}", "", version);
 
         if version.starts_with("dev-") || version.ends_with("-dev") {
             return "dev".to_string();
@@ -143,8 +143,7 @@ impl VersionParser {
                 MODIFIER_REGEX
             );
             if php::preg_match(&datetime_pattern, &version, &mut matches) > 0 {
-                version = php::preg_replace("{\\D}", ".", matches[1].as_deref().unwrap_or(""))
-                    .unwrap_or_default();
+                version = php::preg_replace("{\\D}", ".", matches[1].as_deref().unwrap_or(""));
                 index = Some(2);
             }
         }
@@ -297,8 +296,7 @@ impl VersionParser {
     pub fn parse_constraints(&self, constraints: &str) -> anyhow::Result<AnyConstraint> {
         let pretty_constraint = constraints.to_string();
 
-        let or_constraints = php::preg_split("{\\s*\\|\\|?\\s*}", &php::trim(constraints, None))
-            .ok_or_else(|| anyhow::anyhow!("Failed to preg_split string: {}", constraints))?;
+        let or_constraints = php::preg_split("{\\s*\\|\\|?\\s*}", &php::trim(constraints, None));
 
         let mut or_groups: Vec<AnyConstraint> = Vec::new();
 
@@ -306,8 +304,7 @@ impl VersionParser {
             let and_constraints = php::preg_split(
                 "{(?<!^|as|[=>< ,]) *(?<!-)[, ](?!-) *(?!,|as|$)}",
                 or_constraint,
-            )
-            .ok_or_else(|| anyhow::anyhow!("Failed to preg_split string: {}", or_constraint))?;
+            );
 
             let constraint_objects: Vec<AnyConstraint> = if and_constraints.len() > 1 {
                 let mut objs: Vec<AnyConstraint> = Vec::new();