bench(independent): freeze population v3 (PHP)

freeze.py, extended for v3 and still reading only git history, file lists and
fix diffs:
- a file the advisory names without a function resolves to the function(s)
  the fix's diff changes at the vulnerable pin (maintainer's decision 2),
  recorded with its basis (advisory-named / resolved-from-fix-diff); a new
  helper inserted at file scope adds no site;
- an inferred fix must change a declared site function, else the case drops;
- a single-language population gets a strict benign proposal (PHP change,
  merges judged with all they bring in, pre-vulnerable history as fallback).

All 15 cases verified, none dropped (pagible and podlove fixes confirmed).
Nine sites in eight cases resolved from diffs; five benign proposals
replaced by hand.

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo

tests/test_independent_freeze.py

@@ -0,0 +1,59 @@
+"""freeze.py resolves an advisory's file-only site to the function the fix changes (population v3, decision 2).
+
+The resolver reads PHP text only; it must not be fooled by braces in strings, comments or inline HTML, and a line
+outside every function is `<global>`."""
+
+from __future__ import annotations
+
+import importlib.util
+from pathlib import Path
+
+SPEC = importlib.util.spec_from_file_location("freeze", Path(__file__).resolve().parents[1] / "benchmarks" / "independent" / "freeze.py")
+freeze = importlib.util.module_from_spec(SPEC)
+SPEC.loader.exec_module(freeze)
+
+PHP = """<html>{ not code }</html>
+<?php
+// a comment with { brace
+class Box
+{
+    public function open($x)
+    {
+        $s = "}{ in a string";
+        return function ($y) { return $y; };
+    }
+
+    abstract protected function shape();
+
+    private static function &close() {
+        /* } */
+        return <<<EOT
+        } heredoc {
+        EOT;
+    }
+}
+$top = 1;
+?>
+<div>{</div>
+<?php function helper() { return '#{'; }
+"""
+
+
+def test_named_functions_and_their_lines() -> None:
+    spans = {name: (first, last) for name, first, last in freeze.php_functions(PHP)}
+    assert spans == {"open": (6, 10), "close": (14, 19), "helper": (24, 24)}
+
+
+def test_a_line_resolves_to_its_innermost_named_function_or_global() -> None:
+    spans = freeze.php_functions(PHP)
+    assert freeze.enclosing(spans, 9) == "open"  # inside the closure: the named function owns it
+    assert freeze.enclosing(spans, 17) == "close"
+    assert freeze.enclosing(spans, 21) == "<global>"
+    assert freeze.enclosing(spans, 1) == "<global>"
+
+
+def test_an_insertion_after_a_closing_brace_is_outside_the_function() -> None:
+    spans = freeze.php_functions(PHP)
+    assert freeze.enclosing(spans, 10) == "open"  # a changed line on the closing brace
+    assert freeze.enclosing(spans, 10, inserted=True) == "<global>"  # new code that follows it
+    assert freeze.enclosing(spans, 8, inserted=True) == "open"