Do not transform JSX tag names for ES3

src/compiler/transformers/es5.ts

@@ -9,6 +9,20 @@ namespace ts {
      * @param context Context and state information for the transformation.
      */
     export function transformES5(context: TransformationContext) {
+        const compilerOptions = context.getCompilerOptions();
+
+        // enable emit notification only if using --jsx preserve
+        let previousOnEmitNode: (emitContext: EmitContext, node: Node, emitCallback: (emitContext: EmitContext, node: Node) => void) => void;
+        let noSubstitution: boolean[];
+        if (compilerOptions.jsx === JsxEmit.Preserve) {
+            previousOnEmitNode = context.onEmitNode;
+            context.onEmitNode = onEmitNode;
+            context.enableEmitNotification(SyntaxKind.JsxOpeningElement);
+            context.enableEmitNotification(SyntaxKind.JsxClosingElement);
+            context.enableEmitNotification(SyntaxKind.JsxSelfClosingElement);
+            noSubstitution = [];
+        }
+
         const previousOnSubstituteNode = context.onSubstituteNode;
         context.onSubstituteNode = onSubstituteNode;
         context.enableSubstitution(SyntaxKind.PropertyAccessExpression);
@@ -24,13 +38,35 @@ namespace ts {
             return node;
         }
 
+        /**
+         * Called by the printer just before a node is printed.
+         *
+         * @param node The node to be printed.
+         */
+        function onEmitNode(emitContext: EmitContext, node: Node, emitCallback: (emitContext: EmitContext, node: Node) => void) {
+            switch (node.kind) {
+                case SyntaxKind.JsxOpeningElement:
+                case SyntaxKind.JsxClosingElement:
+                case SyntaxKind.JsxSelfClosingElement:
+                    const tagName = (<JsxOpeningElement | JsxClosingElement | JsxSelfClosingElement>node).tagName;
+                    noSubstitution[getOriginalNodeId(tagName)] = true;
+                    break;
+            }
+
+            previousOnEmitNode(emitContext, node, emitCallback);
+        }
+
         /**
          * Hooks node substitutions.
          *
          * @param emitContext The context for the emitter.
          * @param node The node to substitute.
          */
         function onSubstituteNode(emitContext: EmitContext, node: Node) {
+            if (node.id && noSubstitution && noSubstitution[node.id]) {
+                return previousOnSubstituteNode(emitContext, node);
+            }
+
             node = previousOnSubstituteNode(emitContext, node);
             if (isPropertyAccessExpression(node)) {
                 return substitutePropertyAccessExpression(node);

tests/baselines/reference/jsxViaImport.2.js

@@ -0,0 +1,44 @@
+//// [tests/cases/compiler/jsxViaImport.2.tsx] ////
+
+//// [component.d.ts]
+
+declare module JSX {
+  interface ElementAttributesProperty { props; }
+}
+declare module React {
+  class Component<T, U> { }
+}
+declare module "BaseComponent" {
+    export default class extends React.Component<any, {}> {
+    }
+}
+
+//// [consumer.tsx]
+/// <reference path="component.d.ts" />
+import BaseComponent from 'BaseComponent';
+class TestComponent extends React.Component<any, {}> {
+    render() {
+        return <BaseComponent />;
+    }
+}
+
+
+//// [consumer.jsx]
+"use strict";
+var __extends = (this && this.__extends) || function (d, b) {
+    for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p];
+    function __() { this.constructor = d; }
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
+};
+/// <reference path="component.d.ts" />
+var BaseComponent_1 = require("BaseComponent");
+var TestComponent = (function (_super) {
+    __extends(TestComponent, _super);
+    function TestComponent() {
+        return _super.apply(this, arguments) || this;
+    }
+    TestComponent.prototype.render = function () {
+        return <BaseComponent_1.default />;
+    };
+    return TestComponent;
+}(React.Component));

tests/baselines/reference/jsxViaImport.2.symbols

@@ -0,0 +1,44 @@
+=== tests/cases/compiler/consumer.tsx ===
+/// <reference path="component.d.ts" />
+import BaseComponent from 'BaseComponent';
+>BaseComponent : Symbol(BaseComponent, Decl(consumer.tsx, 1, 6))
+
+class TestComponent extends React.Component<any, {}> {
+>TestComponent : Symbol(TestComponent, Decl(consumer.tsx, 1, 42))
+>React.Component : Symbol(React.Component, Decl(component.d.ts, 4, 22))
+>React : Symbol(React, Decl(component.d.ts, 3, 1))
+>Component : Symbol(React.Component, Decl(component.d.ts, 4, 22))
+
+    render() {
+>render : Symbol(TestComponent.render, Decl(consumer.tsx, 2, 54))
+
+        return <BaseComponent />;
+>BaseComponent : Symbol(BaseComponent, Decl(consumer.tsx, 1, 6))
+    }
+}
+
+=== tests/cases/compiler/component.d.ts ===
+
+declare module JSX {
+>JSX : Symbol(JSX, Decl(component.d.ts, 0, 0))
+
+  interface ElementAttributesProperty { props; }
+>ElementAttributesProperty : Symbol(ElementAttributesProperty, Decl(component.d.ts, 1, 20))
+>props : Symbol(ElementAttributesProperty.props, Decl(component.d.ts, 2, 39))
+}
+declare module React {
+>React : Symbol(React, Decl(component.d.ts, 3, 1))
+
+  class Component<T, U> { }
+>Component : Symbol(Component, Decl(component.d.ts, 4, 22))
+>T : Symbol(T, Decl(component.d.ts, 5, 18))
+>U : Symbol(U, Decl(component.d.ts, 5, 20))
+}
+declare module "BaseComponent" {
+    export default class extends React.Component<any, {}> {
+>React.Component : Symbol(React.Component, Decl(component.d.ts, 4, 22))
+>React : Symbol(React, Decl(component.d.ts, 3, 1))
+>Component : Symbol(React.Component, Decl(component.d.ts, 4, 22))
+    }
+}
+

tests/baselines/reference/jsxViaImport.2.types

@@ -0,0 +1,45 @@
+=== tests/cases/compiler/consumer.tsx ===
+/// <reference path="component.d.ts" />
+import BaseComponent from 'BaseComponent';
+>BaseComponent : typeof BaseComponent
+
+class TestComponent extends React.Component<any, {}> {
+>TestComponent : TestComponent
+>React.Component : React.Component<any, {}>
+>React : typeof React
+>Component : typeof React.Component
+
+    render() {
+>render : () => any
+
+        return <BaseComponent />;
+><BaseComponent /> : any
+>BaseComponent : typeof BaseComponent
+    }
+}
+
+=== tests/cases/compiler/component.d.ts ===
+
+declare module JSX {
+>JSX : any
+
+  interface ElementAttributesProperty { props; }
+>ElementAttributesProperty : ElementAttributesProperty
+>props : any
+}
+declare module React {
+>React : typeof React
+
+  class Component<T, U> { }
+>Component : Component<T, U>
+>T : T
+>U : U
+}
+declare module "BaseComponent" {
+    export default class extends React.Component<any, {}> {
+>React.Component : React.Component<any, {}>
+>React : typeof React
+>Component : typeof React.Component
+    }
+}
+

tests/cases/compiler/jsxViaImport.2.tsx

@@ -0,0 +1,23 @@
+//@jsx: preserve
+//@module: commonjs
+
+//@filename: component.d.ts
+declare module JSX {
+  interface ElementAttributesProperty { props; }
+}
+declare module React {
+  class Component<T, U> { }
+}
+declare module "BaseComponent" {
+    export default class extends React.Component<any, {}> {
+    }
+}
+
+//@filename: consumer.tsx
+/// <reference path="component.d.ts" />
+import BaseComponent from 'BaseComponent';
+class TestComponent extends React.Component<any, {}> {
+    render() {
+        return <BaseComponent />;
+    }
+}