TypeScriptToLua · Perryvw · Feb 17, 2019 · Feb 17, 2019 · Feb 17, 2019 · Feb 17, 2019
diff --git a/src/Compiler.ts b/src/Compiler.ts
@@ -89,8 +89,7 @@ const defaultCompilerOptions: CompilerOptions = {
 };
 
 export function createStringCompilerProgram(
-    input: string, options: CompilerOptions = defaultCompilerOptions): ts.Program {
-
+    input: string, options: CompilerOptions = defaultCompilerOptions, filePath = "file.ts"): ts.Program {
     const compilerHost =  {
         directoryExists: () => true,
         fileExists: (fileName): boolean => true,
@@ -100,8 +99,8 @@ export function createStringCompilerProgram(
         getDirectories: () => [],
         getNewLine: () => "\n",
 
-        getSourceFile: (filename: string, languageVersion) => {
-            if (filename === "file.ts") {
+        getSourceFile: (filename: string) => {
+            if (filename === filePath) {
                 return ts.createSourceFile(filename, input, ts.ScriptTarget.Latest, false);
             }
             if (filename.indexOf(".d.ts") !== -1) {
@@ -126,15 +125,16 @@ export function createStringCompilerProgram(
         // Don't write output
         writeFile: (name, text, writeByteOrderMark) => undefined,
     };
-    return ts.createProgram(["file.ts"], options, compilerHost);
+    return ts.createProgram([filePath], options, compilerHost);
 }
 
 export function transpileString(
     str: string,
     options: CompilerOptions = defaultCompilerOptions,
-    ignoreDiagnostics = false
+    ignoreDiagnostics = false,
+    filePath = "file.ts"
 ): string {
-    const program = createStringCompilerProgram(str, options);
+    const program = createStringCompilerProgram(str, options, filePath);
 
     if (!ignoreDiagnostics) {
         const diagnostics = ts.getPreEmitDiagnostics(program);
@@ -148,7 +148,7 @@ export function transpileString(
 
     const transpiler = new LuaTranspiler(program);
 
-    const result = transpiler.transpileSourceFile(program.getSourceFile("file.ts"));
+    const result = transpiler.transpileSourceFile(program.getSourceFile(filePath));
 
     return result.trim();
 }
diff --git a/src/LuaTransformer.ts b/src/LuaTransformer.ts
@@ -93,27 +93,41 @@ export class LuaTransformer {
     // TODO make all other methods private???
     public transformSourceFile(node: ts.SourceFile): [tstl.Block, Set<LuaLibFeature>] {
         this.setupState();
-        this.pushScope(ScopeType.File, node);
 
         this.currentSourceFile = node;
-        this.isModule = tsHelper.isFileModule(node);
 
-        const statements = this.performHoisting(this.transformStatements(node.statements));
-        this.popScope();
+        let statements: tstl.Statement[] = [];
+        if (node.flags & ts.NodeFlags.JsonFile) {
+            this.isModule = false;
 
-        if (this.isModule) {
-            statements.unshift(
-                tstl.createVariableDeclarationStatement(
-                    tstl.createIdentifier("exports"),
-                    tstl.createBinaryExpression(
+            const statement = node.statements[0];
+            if (!statement || !ts.isExpressionStatement(statement)) {
+                throw TSTLErrors.InvalidJsonFileContent(node);
+            }
+
+            statements.push(tstl.createReturnStatement([this.transformExpression(statement.expression)]));
+        } else {
+            this.pushScope(ScopeType.File, node);
+
+            this.isModule = tsHelper.isFileModule(node);
+            statements = this.performHoisting(this.transformStatements(node.statements));
+
+            this.popScope();
+
+            if (this.isModule) {
+                statements.unshift(
+                    tstl.createVariableDeclarationStatement(
                         tstl.createIdentifier("exports"),
-                        tstl.createTableExpression(),
-                        tstl.SyntaxKind.OrOperator
-                    )));
-            statements.push(
-                tstl.createReturnStatement(
-                    [tstl.createIdentifier("exports")]
-                ));
+                        tstl.createBinaryExpression(
+                            tstl.createIdentifier("exports"),
+                            tstl.createTableExpression(),
+                            tstl.SyntaxKind.OrOperator
+                        )));
+                statements.push(
+                    tstl.createReturnStatement(
+                        [tstl.createIdentifier("exports")]
+                    ));
+            }
         }
 
         return [tstl.createBlock(statements, node), this.luaLibFeatureSet];
@@ -3644,7 +3658,7 @@ export class LuaTransformer {
     }
 
     private pathToLuaRequirePath(filePath: string): string {
-        return filePath.replace(new RegExp("\\\\|\/", "g"), ".");
+        return filePath.replace(new RegExp("\\\\|\/", "g"), ".").replace(/\.json$/, '');
     }
 
     private shouldExportIdentifier(identifier: tstl.Identifier | tstl.Identifier[]): boolean {

diff --git a/src/TSTLErrors.ts b/src/TSTLErrors.ts
@@ -141,4 +141,6 @@ export class TSTLErrors {
             node
         );
     }
+
+    public static InvalidJsonFileContent = (node: ts.Node) => new TranspileError("Invalid JSON file content", node);
 }
diff --git a/test/src/util.ts b/test/src/util.ts
@@ -31,7 +31,7 @@ export function transpileString(str: string, options?: CompilerOptions, ignoreDi
     }
 }
 
-function executeLua(luaStr: string, withLib = true): any {
+export function executeLua(luaStr: string, withLib = true): any {
     if (withLib) {
         luaStr = minimalTestLib + luaStr;
     }

diff --git a/test/unit/json.spec.ts b/test/unit/json.spec.ts
@@ -0,0 +1,27 @@
+import { Expect, Test, TestCase } from "alsatian";
+import { transpileString } from "../../src/Compiler";
+import { TranspileError } from "../../src/TranspileError";
+import * as util from "../src/util";
+
+export class JsonTests {
+    @Test("JSON")
+    @TestCase("0")
+    @TestCase('""')
+    @TestCase("[]")
+    @TestCase('[1, "2", []]')
+    @TestCase('{ "a": "b" }')
+    @TestCase('{ "a": { "b": "c" } }')
+    public json(json: string): void {
+        const lua = transpileString(json, { resolveJsonModule: true, noHeader: true }, false, "file.json")
+            .replace(/^return (.+);$/s, "return JSONStringify($1);");
+
+        const result = util.executeLua(lua);
+        Expect(JSON.parse(result)).toEqual(JSON.parse(json));
+    }
+
+    @Test("Empty JSON")
+    public emptyJson(): void {
+        Expect(() => transpileString("", { resolveJsonModule: true, noHeader: true }, false, "file.json"))
+            .toThrowError(TranspileError, "Invalid JSON file content");
+    }
+}
-Original file line number
+Diff line change
@@ Expand Up / @@ -141,4 +141,6 @@ export class TSTLErrors { @@
                 node
             );
         }
+        public static InvalidJsonFileContent = (node: ts.Node) => new TranspileError("Invalid JSON file content", node);
     }