From 2527da37c616dd02c818b8d099f823a8ae063da1 Mon Sep 17 00:00:00 2001
From: Ryan Cavanaugh <RyanCavanaugh@users.noreply.github.com>
Date: Mon, 2 Jul 2018 14:15:44 -0700
Subject: [PATCH] Handle JSON extension correctly

---
 src/compiler/tsbuild.ts | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/compiler/tsbuild.ts b/src/compiler/tsbuild.ts
index fd677941079..45587447962 100644
--- a/src/compiler/tsbuild.ts
+++ b/src/compiler/tsbuild.ts
@@ -291,19 +291,20 @@ namespace ts {
     function getOutputJavaScriptFileName(inputFileName: string, configFile: ParsedCommandLine) {
         const relativePath = getRelativePathFromDirectory(rootDirOfOptions(configFile.options, configFile.options.configFilePath!), inputFileName, /*ignoreCase*/ true);
         const outputPath = resolvePath(configFile.options.outDir || getDirectoryPath(configFile.options.configFilePath!), relativePath);
-        return changeExtension(outputPath, (fileExtensionIs(inputFileName, Extension.Tsx) && configFile.options.jsx === JsxEmit.Preserve) ? Extension.Jsx : Extension.Js);
+        const newExtension = fileExtensionIs(inputFileName, Extension.Json) ? Extension.Json :
+                             fileExtensionIs(inputFileName, Extension.Tsx) && configFile.options.jsx === JsxEmit.Preserve ? Extension.Jsx : Extension.Js;
+        return changeExtension(outputPath, newExtension);
     }
 
-    const extensionsWithNoOutput: ReadonlyArray<string> = [Extension.Dts, Extension.Json];
     function getOutputFileNames(inputFileName: string, configFile: ParsedCommandLine): ReadonlyArray<string> {
         // outFile is handled elsewhere; .d.ts files don't generate outputs
-        if (configFile.options.outFile || configFile.options.out || fileExtensionIsOneOf(inputFileName, extensionsWithNoOutput)) {
+        if (configFile.options.outFile || configFile.options.out || fileExtensionIs(inputFileName, Extension.Dts)) {
             return emptyArray;
         }
 
         const outputs: string[] = [];
         outputs.push(getOutputJavaScriptFileName(inputFileName, configFile));
-        if (configFile.options.declaration) {
+        if (configFile.options.declaration && !fileExtensionIs(inputFileName, Extension.Json)) {
             const dts = getOutputDeclarationFileName(inputFileName, configFile);
             outputs.push(dts);
             if (configFile.options.declarationMap) {