feat(vtag): passthrough fast-path skips Roslyn for mirror scripts (A)

2026-06-07 15:26:20 -04:00
parent 3834400f05
commit 08d7477860
5 changed files with 256 additions and 3 deletions
@@ -0,0 +1,29 @@
+namespace ZB.MOM.WW.OtOpcUa.Core.Scripting;
+
+using System.Text.RegularExpressions;
+
+/// <summary>
+/// Classifies the trivial "mirror" VirtualTag script shape <c>return ctx.GetTag("X").Value;</c>,
+/// which can be evaluated by returning the dependency value directly — no Roslyn compilation.
+/// Narrow, exact pattern: any near-miss returns false and falls through to the Roslyn path.
+/// </summary>
+public static partial class PassthroughScript
+{
+    // ^ \s* return \s+ ctx . GetTag ( "X" ) . Value ; \s* $  (whitespace-tolerant around tokens)
+    [GeneratedRegex(@"^\s*return\s+ctx\s*\.\s*GetTag\s*\(\s*""([^""]+)""\s*\)\s*\.\s*Value\s*;\s*$")]
+    private static partial Regex MirrorRegex();
+
+    /// <summary>True if <paramref name="source"/> is the mirror passthrough shape; outputs the referenced tag.</summary>
+    /// <param name="source">The VirtualTag script source to classify.</param>
+    /// <param name="tagRef">On success, the tag reference captured from the mirror shape; otherwise empty.</param>
+    /// <returns><see langword="true"/> if the source is the mirror passthrough shape; otherwise <see langword="false"/>.</returns>
+    public static bool TryMatch(string? source, out string tagRef)
+    {
+        tagRef = string.Empty;
+        if (string.IsNullOrEmpty(source)) return false;
+        var m = MirrorRegex().Match(source);
+        if (!m.Success) return false;
+        tagRef = m.Groups[1].Value;
+        return true;
+    }
+}