Add diagnostic for unexpected second identifier

Author: kimdv

Sources/SwiftParserDiagnostics/ParseDiagnosticsGenerator.swift

@@ -810,6 +810,24 @@ public class ParseDiagnosticsGenerator: SyntaxAnyVisitor {
     return .visitChildren
   }
 
+    public override func visit(_ node: PatternBindingSyntax) -> SyntaxVisitorContinueKind {
+        if shouldSkip(node) {
+            return .skipChildren
+        }
+
+        if let unexpected = (node.pattern.as(TuplePatternSyntax.self)?.unexpectedBetweenElementsAndRightParen),
+            let previousToken = node.previousToken(viewMode: .sourceAccurate) {
+            addDiagnostic(unexpected, SpaceSeparatedIdentifiersError(firstToken: previousToken, additionalTokens: []))
+        }
+
+        if let unexpected = node.typeAnnotation?.type, node.typeAnnotation?.colon.hasError == true,
+           let previousToken = node.previousToken(viewMode: .sourceAccurate) {
+            addDiagnostic(unexpected, SpaceSeparatedIdentifiersError(firstToken: previousToken, additionalTokens: []))
+        }
+
+        return .visitChildren
+    }
+
   public override func visit(_ node: PrecedenceGroupAssignmentSyntax) -> SyntaxVisitorContinueKind {
     if shouldSkip(node) {
       return .skipChildren

Tests/SwiftParserTest/translated/RecoveryTests.swift

@@ -814,8 +814,9 @@ final class RecoveryTests: XCTestCase {
       diagnostics: [
         DiagnosticSpec(locationMarker: "1️⃣", message: "found an unexpected second identifier in struct"),
         DiagnosticSpec(locationMarker: "2️⃣", message: "expected ':' in type annotation"),
-        DiagnosticSpec(locationMarker: "3️⃣", message: #"unexpected code ': Int = ""' before function"#),
         // TODO: (good first issue) Old parser expected error on line 4: found an unexpected second identifier in variable declaration; is there an accidental break?
+        DiagnosticSpec(locationMarker: "3️⃣", message: "found an unexpected second identifier in variable declaration; is there an accidental break?"),
+        DiagnosticSpec(locationMarker: "3️⃣", message: #"unexpected code ': Int = ""' before function"#),
         DiagnosticSpec(locationMarker: "4️⃣", message: "expected ':' in type annotation"),
       ]
     )
@@ -828,7 +829,7 @@ final class RecoveryTests: XCTestCase {
       """,
       diagnostics: [
         // TODO: (good first issue) Old parser expected error on line 1: found an unexpected second identifier in constant declaration; is there an accidental break?
-        DiagnosticSpec(message: "unexpected code 'hij, foobar' in tuple pattern")
+        DiagnosticSpec(message: "found an unexpected second identifier in constant declaration; is there an accidental break?")
       ]
     )
   }