[messages] Enforce camelCase in messages.yaml files.

Now that the `messages.yaml` files have been converted to consistently
use camelCase for message names, it is no longer necessary for the
logic that consumes `messages.yaml` files to support other case
conventions.

Change-Id: I6a6a69645d6409c12ef409f6b27ae07cc2403557
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/467080
Reviewed-by: Brian Wilkerson <[email protected]>
Commit-Queue: Paul Berry <[email protected]>
Reviewed-by: Konstantin Shcheglov <[email protected]>

Author: stereotype441

pkg/analyzer/test/verify_diagnostics_test.dart

@@ -375,9 +375,8 @@ class DocumentationValidator {
         message.documentation,
       );
       if (docs != null) {
-        codeName =
-            (message.sharedName ?? message.analyzerCode).lowerSnakeCaseName;
-        variableName = message.analyzerCode.lowerSnakeCaseName;
+        codeName = (message.sharedName ?? message.analyzerCode).snakeCaseName;
+        variableName = message.analyzerCode.snakeCaseName;
         if (unverifiedDocs.contains(variableName)) {
           continue;
         }

pkg/analyzer_utilities/lib/analyzer_messages.dart

@@ -196,9 +196,13 @@ List<M> decodeAnalyzerMessagesYaml<M extends AnalyzerMessage>(
         key: keyNode,
         value: diagnosticValue,
         decoder: (messageYaml) {
-          var analyzerCode = DiagnosticCodeName.fromCamelOrSnakeCase(
-            diagnosticName,
-          );
+          if (!diagnosticName.isCamelCase) {
+            throw LocatedError(
+              'Message names should be camelCase',
+              span: keyNode.span,
+            );
+          }
+          var analyzerCode = DiagnosticCodeName.fromCamelCase(diagnosticName);
           return decodeMessage(
             messageYaml,
             analyzerCode: analyzerCode,
@@ -625,7 +629,7 @@ LocatableDiagnostic $withArgumentsName({$withArgumentsParams}) {
     outputConstantHeader(constant);
     constant.writeln('const $staticType $constantName =');
     constant.writeln('$concreteClassName(');
-    var name = (sharedName?.snakeCaseName ?? diagnosticCode).toLowerCase();
+    var name = sharedName?.snakeCaseName ?? diagnosticCode;
     constant.writeln("name: '$name',");
     var maxWidth = 80 - 8 /* indentation */ - 2 /* quotes */ - 1 /* comma */;
     var messageAsCode = convertTemplate(problemMessage);
@@ -652,7 +656,7 @@ LocatableDiagnostic $withArgumentsName({$withArgumentsParams}) {
     if (baseClasses.requiresTypeArgument) {
       constant.writeln('type: ${type.code},');
     }
-    String uniqueName = analyzerCode.snakeCaseName.toLowerCase();
+    String uniqueName = analyzerCode.snakeCaseName;
     constant.writeln("uniqueName: '$uniqueName',");
     if (withArgumentsName != null) {
       constant.writeln('withArguments: $withArgumentsName,');

pkg/analyzer_utilities/lib/messages.dart

@@ -176,11 +176,8 @@ abstract class CfeStyleMessage extends Message {
         var s when s.isCamelCase => DiagnosticCodeName.fromCamelCase(
           messageYaml.keyString,
         ),
-        var s when s.isPascalCase => DiagnosticCodeName.fromPascalCase(
-          messageYaml.keyString,
-        ),
         _ => throw LocatedError(
-          'Front end codes must be camelCase or PascalCase',
+          'Front end codes must be camelCase',
           span: messageYaml.keySpan,
         ),
       },
@@ -239,12 +236,8 @@ class DiagnosticCodeName implements Comparable<DiagnosticCodeName> {
     'linesLongerThan80Chars': 'lines_longer_than_80_chars',
   };
 
-  /// The diagnostic name, as a "snake case" name (words separated by
-  /// underscores).
-  ///
-  /// The name might be lower case or upper case.
-  // TODO(paulberry): change `messages.yaml` to consistently use lower snake
-  // case, and remove [lowerSnakeCaseName].
+  /// The diagnostic name, as a "lower snake case" name (lower case words
+  /// separated by underscores).
   final String snakeCaseName;
 
   /// The diagnostic name, as a "camel case" name (lower case word followed by
@@ -264,38 +257,13 @@ class DiagnosticCodeName implements Comparable<DiagnosticCodeName> {
     }
   }
 
-  factory DiagnosticCodeName.fromCamelOrSnakeCase(String value) =>
-      value.isCamelCase
-      ? DiagnosticCodeName.fromCamelCase(value)
-      : DiagnosticCodeName.fromSnakeCase(value);
-
-  factory DiagnosticCodeName.fromPascalCase(String pascalCaseName) {
-    var snakeCaseName = pascalCaseName.toSnakeCase();
-    var camelCaseName = snakeCaseName.toPascalCase();
-    return DiagnosticCodeName._(
-      snakeCaseName: snakeCaseName,
-      camelCaseName: camelCaseName,
-    );
-  }
-
-  DiagnosticCodeName.fromSnakeCase(this.snakeCaseName)
-    : camelCaseName = snakeCaseName.toCamelCase();
-
-  DiagnosticCodeName._({
-    required this.snakeCaseName,
-    required this.camelCaseName,
-  });
-
   /// The string that should be generated into analyzer source code to refer to
   /// this diagnostic code.
   String get analyzerCodeReference => ['diag', camelCaseName].join('.');
 
   @override
   int get hashCode => snakeCaseName.hashCode;
 
-  /// The diagnostic name, converted to lower snake case.
-  String get lowerSnakeCaseName => snakeCaseName.toLowerCase();
-
   /// The diagnostic name, converted to PascalCase.
   String get pascalCaseName => snakeCaseName.toPascalCase();
 
@@ -662,10 +630,17 @@ abstract class Message {
             isRequired: requireProblemMessage,
           ) ??
           [],
-      sharedName = switch (messageYaml.getOptionalString('sharedName')) {
-        var s? => DiagnosticCodeName.fromCamelOrSnakeCase(s),
-        null => null,
-      },
+      sharedName = messageYaml.get(
+        'sharedName',
+        decode: (s) => switch (s) {
+          YamlScalar(:String value) =>
+            value.isCamelCase
+                ? DiagnosticCodeName.fromCamelCase(value)
+                : throw 'Shared names should be camelCase',
+          _ => throw 'Must be a string',
+        },
+        ifAbsent: () => null,
+      ),
       removedIn = messageYaml.getOptionalString('removedIn'),
       previousName = messageYaml.getOptionalString('previousName'),
       parameters = messageYaml.parameters,
@@ -1008,15 +983,11 @@ class SharedMessage extends CfeStyleMessage with MessageWithAnalyzerCode {
     switch (node) {
       case YamlScalar(value: String s):
         switch (s.split('.')) {
-          case [_, var snakeCaseName]
-              when snakeCaseName == snakeCaseName.toUpperCase():
-            return DiagnosticCodeName.fromSnakeCase(snakeCaseName);
           case [var camelCaseName] when camelCaseName.isCamelCase:
             return DiagnosticCodeName.fromCamelCase(camelCaseName);
         }
     }
-    throw 'Analyzer codes must be either camelCase names or must take the form '
-        'ClassName.DIAGNOSTIC_NAME.';
+    throw 'Analyzer codes must be camelCase names.';
   }
 }
 

pkg/linter/tool/messages_info.dart

@@ -13,7 +13,7 @@ const String _messagesFileName = 'pkg/linter/messages.yaml';
 final Map<String, RuleInfo> messagesRuleInfo = () {
   {
     var lintNames = lintMessages
-        .map((m) => m.analyzerCode.lowerSnakeCaseName)
+        .map((m) => m.analyzerCode.snakeCaseName)
         .toList(growable: false);
     var lintCodeKeysSorted = lintNames.sorted();
     for (var i = 0; i < lintNames.length; i++) {
@@ -29,12 +29,12 @@ final Map<String, RuleInfo> messagesRuleInfo = () {
   var builders = <String, _RuleBuilder>{};
   for (var message in lintMessages) {
     var sharedNameString =
-        (message.sharedName ?? message.analyzerCode).lowerSnakeCaseName;
+        (message.sharedName ?? message.analyzerCode).snakeCaseName;
     var rule = builders.putIfAbsent(
       sharedNameString,
       () => _RuleBuilder(sharedNameString),
     );
-    rule.addEntry(message.analyzerCode.lowerSnakeCaseName, message);
+    rule.addEntry(message.analyzerCode.snakeCaseName, message);
   }
 
   return builders.map((key, value) {