Replace all raw string comparisons with StringKey, source generator that creates cache keys for all names for Gen7 plugin

Plugins/PkmnLib.Plugin.Gen7.SourceGen/Emit/ConstantClassEmitter.cs

@@ -0,0 +1,73 @@
+using System.Text;
+using PkmnLib.Plugin.Gen7.SourceGen.Parsing;
+
+namespace PkmnLib.Plugin.Gen7.SourceGen.Emit;
+
+/// <summary>
+/// Emits a constants class of <c>public static readonly StringKey</c> fields for a
+/// <see cref="ClassSpec"/>.
+/// </summary>
+public static class ConstantClassEmitter
+{
+    public static string Emit(ClassSpec spec, List<ExtractionDiagnostic> diagnostics)
+    {
+        var sb = new StringBuilder();
+        sb.AppendLine($"// <auto-generated from Data/{spec.SourceFile} by PkmnLib.Plugin.Gen7.SourceGen />");
+        sb.AppendLine("#nullable enable");
+        sb.AppendLine("using PkmnLib.Static.Utils;");
+        sb.AppendLine();
+        sb.AppendLine("namespace PkmnLib.Plugin.Gen7.Common;");
+        sb.AppendLine();
+        sb.AppendLine($"public static class {spec.ClassName}");
+        sb.AppendLine("{");
+        var seen = new Dictionary<string, string>(StringComparer.Ordinal);
+        foreach (var name in spec.Names)
+        {
+            var identifier = Sanitize(name);
+            if (identifier.Length == 0)
+            {
+                diagnostics.Add(new ExtractionDiagnostic("PKMN7G002",
+                    $"Name '{name}' in {spec.ClassName} does not produce a usable identifier and was skipped."));
+                continue;
+            }
+            if (seen.TryGetValue(identifier, out var existing))
+            {
+                diagnostics.Add(new ExtractionDiagnostic("PKMN7G001",
+                    $"Names '{existing}' and '{name}' in {spec.ClassName} both map to identifier '{identifier}'; '{name}' was skipped."));
+                continue;
+            }
+            seen.Add(identifier, name);
+            sb.AppendLine($"    public static readonly StringKey {identifier} = \"{name}\";");
+        }
+        sb.AppendLine("}");
+        return sb.ToString();
+    }
+
+    /// <summary>
+    /// Converts a raw data name to a PascalCase identifier: segments split on <c>_</c>/<c>-</c>
+    /// runs, non-alphanumeric characters stripped, and a leading <c>_</c> added when the result
+    /// would start with a digit.
+    /// </summary>
+    public static string Sanitize(string raw)
+    {
+        var sb = new StringBuilder(raw.Length);
+        var newSegment = true;
+        foreach (var c in raw)
+        {
+            if (c is '_' or '-')
+            {
+                newSegment = true;
+                continue;
+            }
+            if (!char.IsLetterOrDigit(c))
+                continue;
+            sb.Append(newSegment ? char.ToUpperInvariant(c) : c);
+            newSegment = false;
+        }
+        if (sb.Length == 0)
+            return string.Empty;
+        if (char.IsDigit(sb[0]))
+            sb.Insert(0, '_');
+        return sb.ToString();
+    }
+}