refactor(preg): drop the Vec-returning preg_match_all

The two preg_match_all variants took the same arguments and differed
only in what they returned: a Vec of columns, or the named-and-numbered
PregMatchesAll. The latter is the one all but two call sites already
used, so preg_match_all2 takes over the plain PHP name and the Vec
variant goes away.

Its remaining readers only ever wanted group 0's column, which they now
take through CaptureKey::ByIndex(0); in the formatter this replaces the
array_shift that popped that column off the PREG_PATTERN_ORDER array.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

6 files changed, 20 insertions, 32 deletions

diff --git a/crates/shirabe-class-map-generator/src/php_file_parser.rs b/crates/shirabe-class-map-generator/src/php_file_parser.rs
index 0ed78c7f..7cc96228 100644
--- a/crates/shirabe-class-map-generator/src/php_file_parser.rs
+++ b/crates/shirabe-class-map-generator/src/php_file_parser.rs
@@ -3,7 +3,7 @@
 use crate::php_file_cleaner::PhpFileCleaner;
 use shirabe_php_shim::{
     CaptureKey, PHP_EOL, RuntimeException, file_exists, file_get_contents, function_exists,
-    is_file, is_readable, ltrim, php_strip_whitespace, preg_match_all2, str_replace_array, strrpos,
+    is_file, is_readable, ltrim, php_strip_whitespace, preg_match_all, str_replace_array, strrpos,
     substr, trim,
 };
 use std::sync::OnceLock;
@@ -58,7 +58,7 @@ impl PhpFileParser {
 
         // return early if there is no chance of matching anything in this file
         let pattern = format!("{{\\b(?:class|interface|trait{})\\s}}i", extra_types);
-        let max_matches = preg_match_all2(&pattern, &contents).occurrence_count();
+        let max_matches = preg_match_all(&pattern, &contents).occurrence_count();
         if max_matches == 0 {
             return Ok(vec![]);
         }
@@ -84,7 +84,7 @@ impl PhpFileParser {
         }}ix",
             et = extra_types
         );
-        let matches = preg_match_all2(&pattern2, &contents);
+        let matches = preg_match_all(&pattern2, &contents);
 
         let mut classes = vec![];
         let mut namespace = String::new();
diff --git a/crates/shirabe-php-shim/src/preg.rs b/crates/shirabe-php-shim/src/preg.rs
index d8bdcc10..e84f8463 100644
--- a/crates/shirabe-php-shim/src/preg.rs
+++ b/crates/shirabe-php-shim/src/preg.rs
@@ -175,24 +175,9 @@ pub fn preg_match2<'h>(
     Some(PregMatches::new(caps))
 }
 
-// PREG_PATTERN_ORDER: the outer vec is indexed by capture group, the inner by
-// match occurrence. A non-participating group is reported as None.
-pub fn preg_match_all(pattern: impl PregPattern, subject: &str) -> Vec<Vec<Option<String>>> {
-    let __resolved = pattern.resolve();
-    let (re, _anchored) = __resolved.parts();
-    let group_count = re.captures_len();
-    let mut groups: Vec<Vec<Option<String>>> = vec![Vec::new(); group_count];
-    for caps in re.captures_iter(subject) {
-        for (g, group) in groups.iter_mut().enumerate() {
-            group.push(caps.get(g).map(|m| m.as_str().to_string()));
-        }
-    }
-    groups
-}
-
 // The number of occurrences the caller would get from PHP's return value is the length of any
 // one column, as `PregMatchesAll::occurrence_count` reports it.
-pub fn preg_match_all2(pattern: impl PregPattern, subject: &str) -> PregMatchesAll {
+pub fn preg_match_all(pattern: impl PregPattern, subject: &str) -> PregMatchesAll {
     let __resolved = pattern.resolve();
     let (re, _anchored) = __resolved.parts();
     let group_count = re.captures_len();
@@ -473,9 +458,8 @@ fn translate_php_pattern(pattern: &str) -> anyhow::Result<(String, bool)> {
         .collect();
 
     // PCRE's `A` (PCRE_ANCHORED) modifier requires the match to start exactly at the search offset.
-    // The `regex` crate has no per-search anchoring, so the offset-based callers
-    // (`preg_match2`/`preg_match_all2`) honour it by searching a sub-slice that begins at the offset;
-    // here we only surface the flag.
+    // The `regex` crate has no per-search anchoring, so `preg_match2` honours it by searching a
+    // sub-slice that begins at the offset; here we only surface the flag.
     let anchored = modifiers.contains('A');
 
     let inner = translate_pcre_literals(inner);
diff --git a/crates/shirabe-symfony-console/src/completion/completion_input.rs b/crates/shirabe-symfony-console/src/completion/completion_input.rs
index aafa7c8a..41c15ec5 100644
--- a/crates/shirabe-symfony-console/src/completion/completion_input.rs
+++ b/crates/shirabe-symfony-console/src/completion/completion_input.rs
@@ -3,7 +3,7 @@
 use crate::input::ArgvInput;
 use crate::input::InputDefinition;
 use crate::input::InputOption;
-use shirabe_php_shim::{PhpMixed, php_regex, preg_match_all};
+use shirabe_php_shim::{CaptureKey, PhpMixed, php_regex, preg_match_all};
 
 /// An input specialized for shell completion.
 ///
@@ -35,7 +35,9 @@ impl CompletionInput {
         );
 
         Self::from_tokens(
-            tokens[0]
+            tokens
+                .get(&CaptureKey::ByIndex(0))
+                .expect("group 0 is always present")
                 .iter()
                 .map(|token| {
                     token
diff --git a/crates/shirabe-symfony-console/src/formatter/output_formatter.rs b/crates/shirabe-symfony-console/src/formatter/output_formatter.rs
index 256fade1..f4c55573 100644
--- a/crates/shirabe-symfony-console/src/formatter/output_formatter.rs
+++ b/crates/shirabe-symfony-console/src/formatter/output_formatter.rs
@@ -135,12 +135,14 @@ impl OutputFormatter {
                 let url = preg_replace(php_regex!("{\\\\([<>])}"), "$1", &r#match[1]);
                 style.set_href(&url);
             } else if r#match[0] == "options" {
-                let mut options = preg_match_all(
+                let options = preg_match_all(
                     php_regex!("([^,;]+)"),
                     &shirabe_php_shim::strtolower(&r#match[1]),
                 );
-                let options = shirabe_php_shim::array_shift(&mut options).unwrap_or_default();
-                for option in &options {
+                let options = options
+                    .get(&CaptureKey::ByIndex(0))
+                    .expect("group 0 is always present");
+                for option in options {
                     style.set_option(
                         option
                             .as_deref()
diff --git a/crates/shirabe/src/command/init_command.rs b/crates/shirabe/src/command/init_command.rs
index 96bdc58d..b316e4fe 100644
--- a/crates/shirabe/src/command/init_command.rs
+++ b/crates/shirabe/src/command/init_command.rs
@@ -24,7 +24,7 @@ use shirabe_php_shim::{
     CaptureKey, FILE_IGNORE_NEW_LINES, InvalidArgumentException, PHP_EOL, PHP_SERVER, PhpMixed,
     array_flip_strings, array_intersect_key, array_map, basename, empty, explode, file,
     file_exists, file_get_contents, file_put_contents, get_current_user, impl_php_class, implode,
-    is_dir, is_string, php_regex, preg_match_all2, preg_match2, preg_quote, preg_replace, realpath,
+    is_dir, is_string, php_regex, preg_match_all, preg_match2, preg_quote, preg_replace, realpath,
     str_replace, strpos, strtolower, trim, ucwords,
 };
 use shirabe_spdx_licenses::SpdxLicenses;
@@ -168,7 +168,7 @@ impl InitCommand {
         ) == 0
         {
             *self.git_config.borrow_mut() = Some(IndexMap::new());
-            let m = preg_match_all2(php_regex!(r"{^([^=]+)=(.*)$}m"), &output);
+            let m = preg_match_all(php_regex!(r"{^([^=]+)=(.*)$}m"), &output);
             if m.occurrence_count() > 0 {
                 let keys: Vec<Option<String>> =
                     m.get(&CaptureKey::ByIndex(1)).cloned().unwrap_or_default();
diff --git a/crates/shirabe/src/downloader/git_downloader.rs b/crates/shirabe/src/downloader/git_downloader.rs
index d3dea453..6e79576d 100644
--- a/crates/shirabe/src/downloader/git_downloader.rs
+++ b/crates/shirabe/src/downloader/git_downloader.rs
@@ -19,7 +19,7 @@ use crate::util::Url;
 use indexmap::IndexMap;
 use shirabe_php_shim::{
     CaptureKey, CmpOp, PhpMixed, RuntimeException, array_map, basename, dirname, impl_php_class,
-    implode, in_array_strict, is_dir, php_regex, preg_match_all2, preg_match2, preg_quote,
+    implode, in_array_strict, is_dir, php_regex, preg_match_all, preg_match2, preg_quote,
     preg_replace, preg_split, realpath, rtrim, strlen, strpos, substr, trim, version_compare,
 };
 
@@ -100,7 +100,7 @@ impl GitDownloader {
         };
         let head_ref = head_match.get(1).unwrap_or_default().to_string();
 
-        let branches_match = preg_match_all2(
+        let branches_match = preg_match_all(
             format!("{{^{} refs/heads/(.+)$}}mi", preg_quote(&head_ref, None)),
             &refs,
         );
@@ -127,7 +127,7 @@ impl GitDownloader {
 
             // try to find matching branch names in remote repos
             for candidate in &candidate_branches {
-                let m = preg_match_all2(
+                let m = preg_match_all(
                     format!(
                         "{{^[a-f0-9]+ refs/remotes/((?:[^/]+)/{})$}}mi",
                         preg_quote(candidate, None)