Initial check in - Support other JSX factories Issue #3788

- added jsxNamespace compile option
- when jsx mode is "react", jsxNamespace optionally specifies the emit namespace for React calls, eg "--jsxNamespace MyDOMLib" will emit calls as MyDOMLib.createElement (instead of React.createElement)
- symbol specified by jsxNamespace must be present, else compile error is generated (same handling as is done for React symbol when no jsxNamespace is specified)

Author: Rowan Wyborn

src/compiler/checker.ts

@@ -8491,13 +8491,14 @@ namespace ts {
             checkGrammarJsxElement(node);
             checkJsxPreconditions(node);
 
-            // If we're compiling under --jsx react, the symbol 'React' should
+            // If we're compiling under --jsx react, the JSX namespace symbol should
             // be marked as 'used' so we don't incorrectly elide its import. And if there
-            // is no 'React' symbol in scope, we should issue an error.
+            // is no JSX namespace symbol in scope, we should issue an error.
             if (compilerOptions.jsx === JsxEmit.React) {
-                const reactSym = resolveName(node.tagName, "React", SymbolFlags.Value, Diagnostics.Cannot_find_name_0, "React");
-                if (reactSym) {
-                    getSymbolLinks(reactSym).referenced = true;
+                const jsxNamespace = compilerOptions.jsxNamespace ? compilerOptions.jsxNamespace : "React";
+                const jsxSym = resolveName(node.tagName, jsxNamespace, SymbolFlags.Value, Diagnostics.Cannot_find_name_0, jsxNamespace);
+                if (jsxSym) {
+                    getSymbolLinks(jsxSym).referenced = true;
                 }
             }
 

src/compiler/commandLineParser.ts

@@ -54,6 +54,11 @@ namespace ts {
             description: Diagnostics.Specify_JSX_code_generation_Colon_preserve_or_react,
             error: Diagnostics.Argument_for_jsx_must_be_preserve_or_react
         },
+        {
+            name: "jsxNamespace",
+            type: "string",
+            description: Diagnostics.Specify_JSX_emit_namespace_when_JSX_code_generation_mode_is_react
+        },
         {
             name: "listFiles",
             type: "boolean",

src/compiler/diagnosticMessages.json

@@ -2389,6 +2389,10 @@
         "category": "Message",
         "code": 6083
     },
+    "Specify JSX emit namespace when JSX code generation mode is 'react'": {
+        "category": "Message",
+        "code": 6084    
+    },
 
     "Variable '{0}' implicitly has an '{1}' type.": {
         "category": "Error",

src/compiler/emitter.ts

@@ -1192,7 +1192,7 @@ var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, Promi
 
                 function emitJsxElement(openingNode: JsxOpeningLikeElement, children?: JsxChild[]) {
                     const syntheticReactRef = <Identifier>createSynthesizedNode(SyntaxKind.Identifier);
-                    syntheticReactRef.text = "React";
+                    syntheticReactRef.text = compilerOptions.jsxNamespace ? compilerOptions.jsxNamespace : "React";
                     syntheticReactRef.parent = openingNode;
 
                     // Call React.createElement(tag, ...

src/compiler/types.ts

@@ -2382,6 +2382,7 @@ namespace ts {
         inlineSourceMap?: boolean;
         inlineSources?: boolean;
         jsx?: JsxEmit;
+        jsxNamespace? : string;        
         listFiles?: boolean;
         locale?: string;
         mapRoot?: string;