JsxTagNameExpression can only be Identifier | ThisExpression, not any PrimaryExpression (microsoft#21555)

* JsxTagNameExpression can only be Identifier | ThisExpression, not any PrimaryExpression

* Use a type similar to PropertyAccessEntityNameExpression

* Fix lint errors

Author: Andy

src/compiler/checker.ts

@@ -16434,16 +16434,7 @@ namespace ts {
          * Returns true iff React would emit this tag name as a string rather than an identifier or qualified name
          */
         function isJsxIntrinsicIdentifier(tagName: JsxTagNameExpression): boolean {
-            // TODO (yuisu): comment
-            switch (tagName.kind) {
-                case SyntaxKind.PropertyAccessExpression:
-                case SyntaxKind.ThisKeyword:
-                    return false;
-                case SyntaxKind.Identifier:
-                    return isIntrinsicJsxName((<Identifier>tagName).escapedText);
-                default:
-                    return Debug.fail();
-            }
+            return tagName.kind === SyntaxKind.Identifier && isIntrinsicJsxName(tagName.escapedText);
         }
 
         function checkJsxAttribute(node: JsxAttribute, checkMode?: CheckMode) {

src/compiler/emitter.ts

@@ -2451,7 +2451,7 @@ namespace ts {
 
         function emitJsxTagName(node: JsxTagNameExpression) {
             if (node.kind === SyntaxKind.Identifier) {
-                emitExpression(<Identifier>node);
+                emitExpression(node);
             }
             else {
                 emit(node);

src/compiler/parser.ts

@@ -4314,9 +4314,9 @@ namespace ts {
             // We can't just simply use parseLeftHandSideExpressionOrHigher because then we will start consider class,function etc as a keyword
             // We only want to consider "this" as a primaryExpression
             let expression: JsxTagNameExpression = token() === SyntaxKind.ThisKeyword ?
-                parseTokenNode<PrimaryExpression>() : parseIdentifierName();
+                parseTokenNode<ThisExpression>() : parseIdentifierName();
             while (parseOptional(SyntaxKind.DotToken)) {
-                const propertyAccess: PropertyAccessExpression = <PropertyAccessExpression>createNode(SyntaxKind.PropertyAccessExpression, expression.pos);
+                const propertyAccess: JsxTagNamePropertyAccess = <JsxTagNamePropertyAccess>createNode(SyntaxKind.PropertyAccessExpression, expression.pos);
                 propertyAccess.expression = expression;
                 propertyAccess.name = parseRightSideOfDot(/*allowIdentifierNames*/ true);
                 expression = finishNode(propertyAccess);
@@ -7886,7 +7886,7 @@ namespace ts {
         }
 
         if (lhs.kind === SyntaxKind.Identifier) {
-            return (<Identifier>lhs).escapedText === (<Identifier>rhs).escapedText;
+            return lhs.escapedText === (<Identifier>rhs).escapedText;
         }
 
         if (lhs.kind === SyntaxKind.ThisKeyword) {

src/compiler/types.ts

@@ -1761,7 +1761,11 @@ namespace ts {
 
     export type JsxAttributeLike = JsxAttribute | JsxSpreadAttribute;
 
-    export type JsxTagNameExpression = PrimaryExpression | PropertyAccessExpression;
+    export type JsxTagNameExpression = Identifier | ThisExpression | JsxTagNamePropertyAccess;
+
+    export interface JsxTagNamePropertyAccess extends PropertyAccessExpression {
+        expression: JsxTagNameExpression;
+    }
 
     export interface JsxAttributes extends ObjectLiteralExpressionBase<JsxAttributeLike> {
         parent: JsxOpeningLikeElement;

tests/baselines/reference/api/tsserverlibrary.d.ts

@@ -1713,7 +1713,10 @@ declare namespace ts {
     }
     type JsxOpeningLikeElement = JsxSelfClosingElement | JsxOpeningElement;
     type JsxAttributeLike = JsxAttribute | JsxSpreadAttribute;
-    type JsxTagNameExpression = PrimaryExpression | PropertyAccessExpression;
+    type JsxTagNameExpression = Identifier | ThisExpression | JsxTagNamePropertyAccess;
+    interface JsxTagNamePropertyAccess extends PropertyAccessExpression {
+        expression: JsxTagNameExpression;
+    }
     interface JsxAttributes extends ObjectLiteralExpressionBase<JsxAttributeLike> {
         parent: JsxOpeningLikeElement;
     }

tests/baselines/reference/api/typescript.d.ts

@@ -1105,7 +1105,10 @@ declare namespace ts {
     }
     type JsxOpeningLikeElement = JsxSelfClosingElement | JsxOpeningElement;
     type JsxAttributeLike = JsxAttribute | JsxSpreadAttribute;
-    type JsxTagNameExpression = PrimaryExpression | PropertyAccessExpression;
+    type JsxTagNameExpression = Identifier | ThisExpression | JsxTagNamePropertyAccess;
+    interface JsxTagNamePropertyAccess extends PropertyAccessExpression {
+        expression: JsxTagNameExpression;
+    }
     interface JsxAttributes extends ObjectLiteralExpressionBase<JsxAttributeLike> {
         parent: JsxOpeningLikeElement;
     }