TypeScriptToLua · Perryvw · Aug 3, 2022 · Jul 28, 2022 · Jul 30, 2022
diff --git a/src/transpilation/resolve.ts b/src/transpilation/resolve.ts
@@ -147,6 +147,16 @@ class ResolutionContext {
         const fileFromPath = this.getFileFromPath(resolvedPath);
         if (fileFromPath) return fileFromPath;
 
+        if (this.options.paths && this.options.baseUrl) {
+            // If no file found yet and paths are present, try to find project file via paths mappings
+            const fileFromPaths = this.tryGetModuleNameFromPaths(
+                dependencyPath,
+                this.options.paths,
+                this.options.baseUrl
+            );
+            if (fileFromPaths) return fileFromPaths;
+        }
+
         // Not a TS file in our project sources, use resolver to check if we can find dependency
         try {
             const resolveResult = resolver.resolveSync({}, fileDirectory, dependencyPath);
@@ -222,6 +232,40 @@ class ResolutionContext {
             }
         }
     }
+
+    // Taken from TS and modified: https://github.com/microsoft/TypeScript/blob/88a1e3a1dd8d2d86e844ff1c16d5f041cebcfdb9/src/compiler/moduleSpecifiers.ts#L562
+    private tryGetModuleNameFromPaths(relativeToBaseUrl: string, paths: ts.MapLike<string[]>, baseUrl: string) {
+        const relativeImport = removeTrailingDirectorySeparator(normalizeSlashes(relativeToBaseUrl));
+        for (const [importPattern, targetPatterns] of Object.entries(paths)) {
+            const pattern = removeFileExtension(normalizeSlashes(importPattern));
+            const indexOfStar = pattern.indexOf("*");
+            if (indexOfStar !== -1) {
+                // Try to match <prefix>*<suffix> to relativeImport
+                const prefix = pattern.substring(0, indexOfStar);
+                const suffix = pattern.substring(indexOfStar + 1);
+                if (
+                    (relativeImport.length >= prefix.length + suffix.length &&
+                        relativeImport.startsWith(prefix) &&
+                        relativeImport.endsWith(suffix)) ||
+                    (!suffix && relativeImport === removeTrailingDirectorySeparator(prefix))
+                ) {
+                    // If import matches <prefix>*<suffix>, extract the matched * path
+                    const matchedStar = relativeImport.substring(prefix.length, relativeImport.length - suffix.length);
+                    // Try to resolve to the target patterns with filled in * pattern
+                    for (const target of targetPatterns) {
+                        const file = this.getFileFromPath(path.join(baseUrl, target.replace("*", matchedStar)));
+                        if (file) return file;
+                    }
+                }
+            } else if (pattern === relativeImport) {
+                // If there is no * pattern, check for exact matches and try those targets
+                for (const target of targetPatterns) {
+                    const file = this.getFileFromPath(path.join(baseUrl, target));
+                    if (file) return file;
+                }
+            }
+        }
+    }
 }
 
 export function resolveDependencies(program: ts.Program, files: ProcessedFile[], emitHost: EmitHost): ResolutionResult {
@@ -340,3 +384,11 @@ function fallbackResolve(required: string, sourceRootDir: string, fileDir: strin
 function luaRequireToPath(requirePath: string): string {
     return requirePath.replace(/\./g, path.sep);
 }
+
+function removeFileExtension(path: string) {
+    return path.includes(".") ? trimExtension(path) : path;
+}
+
+function removeTrailingDirectorySeparator(path: string) {
+    return path.endsWith("/") || path.endsWith("\\") ? path.substring(0, -1) : path;
+}
diff --git a/test/transpile/__snapshots__/module-resolution.spec.ts.snap b/test/transpile/__snapshots__/module-resolution.spec.ts.snap
@@ -0,0 +1,17 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`supports complicated paths configuration 1`] = `
+Array [
+  "/monorepo-complicated/dist/packages/tstl-program/packages/mypackage/src/bar.lua",
+  "/monorepo-complicated/dist/packages/tstl-program/packages/mypackage/src/index.lua",
+  "/monorepo-complicated/dist/packages/tstl-program/packages/myprogram/src/main.lua",
+]
+`;
+
+exports[`supports paths configuration 1`] = `
+Array [
+  "/monorepo-with-paths/myprogram/dist/mypackage/bar.lua",
+  "/monorepo-with-paths/myprogram/dist/mypackage/index.lua",
+  "/monorepo-with-paths/myprogram/dist/myprogram/main.lua",
+]
+`;
diff --git a/test/transpile/module-resolution.spec.ts b/test/transpile/module-resolution.spec.ts
@@ -2,7 +2,8 @@ import * as path from "path";
 import * as tstl from "../../src";
 import * as util from "../util";
 import * as ts from "typescript";
-import { BuildMode, transpileProject } from "../../src";
+import { BuildMode } from "../../src";
+import { normalizeSlashes } from "../../src/utils";
 
 describe("basic module resolution", () => {
     const projectPath = path.resolve(__dirname, "module-resolution", "project-with-node-modules");
@@ -236,8 +237,8 @@ describe("module resolution project with dependencies built by tstl library mode
     const projectPath = path.resolve(__dirname, "module-resolution", "project-with-tstl-library-modules");
 
     // First compile dependencies into node_modules. NOTE: Actually writing to disk, very slow
-    transpileProject(path.join(projectPath, "dependency1-ts", "tsconfig.json"));
-    transpileProject(path.join(projectPath, "dependency2-ts", "tsconfig.json"));
+    tstl.transpileProject(path.join(projectPath, "dependency1-ts", "tsconfig.json"));
+    tstl.transpileProject(path.join(projectPath, "dependency2-ts", "tsconfig.json"));
 
     const expectedResult = {
         dependency1IndexResult: "function in dependency 1 index: dependency1OtherFileFunc in dependency1/d1otherfile",
@@ -538,3 +539,54 @@ test("lualib_module with parent directory import (#1307)", () => {
         FEATURE_CONSTANT: 456,
     });
 });
+
+test("supports paths configuration", () => {
+    // Package root
+    const baseProjectPath = path.resolve(__dirname, "module-resolution", "monorepo-with-paths");
+    // myprogram package
+    const projectPath = path.join(baseProjectPath, "myprogram");
+    const projectTsConfig = path.join(projectPath, "tsconfig.json");
+    const mainFile = path.join(projectPath, "main.ts");
+
+    const luaResult = util
+        .testProject(projectTsConfig)
+        .setMainFileName(mainFile)
+        .expectToHaveNoDiagnostics()
+        .getLuaResult();
+
+    expect(snapshotPaths(luaResult.transpiledFiles)).toMatchSnapshot();
+
+    // Bundle to have all files required to execute and check result
+    util.testProject(projectTsConfig)
+        .setMainFileName(mainFile)
+        .setOptions({ luaBundle: "bundle.lua", luaBundleEntry: mainFile })
+        .expectToEqual({ foo: 314, bar: 271 });
+});
+
+test("supports complicated paths configuration", () => {
+    // Package root
+    const baseProjectPath = path.resolve(__dirname, "module-resolution", "monorepo-complicated");
+    // myprogram package
+    const projectPath = path.join(baseProjectPath, "packages", "myprogram");
+    const projectTsConfig = path.join(projectPath, "tsconfig.json");
+    const mainFile = path.join(projectPath, "src", "main.ts");
+
+    const luaResult = util
+        .testProject(projectTsConfig)
+        .setMainFileName(mainFile)
+        .expectToHaveNoDiagnostics()
+        .getLuaResult();
+
+    expect(snapshotPaths(luaResult.transpiledFiles)).toMatchSnapshot();
+
+    // Bundle to have all files required to execute
+    util.testProject(projectTsConfig)
+        .setMainFileName(mainFile)
+        .setOptions({ luaBundle: "bundle.lua", luaBundleEntry: mainFile })
+        .debug()
+        .expectToEqual({ foo: 314, bar: 271 });
+});
+
+function snapshotPaths(files: tstl.TranspiledFile[]) {
+    return files.map(f => normalizeSlashes(f.outPath).split("module-resolution")[1]).sort();
+}
diff --git a/test/transpile/module-resolution/monorepo-complicated/packages/mypackage/src/bar.ts b/test/transpile/module-resolution/monorepo-complicated/packages/mypackage/src/bar.ts
@@ -0,0 +1 @@
+export const bar = 271;
diff --git a/test/transpile/module-resolution/monorepo-complicated/packages/mypackage/src/index.ts b/test/transpile/module-resolution/monorepo-complicated/packages/mypackage/src/index.ts
@@ -0,0 +1 @@
+export const foo = 314;
diff --git a/test/transpile/module-resolution/monorepo-complicated/packages/mypackage/tsconfig.json b/test/transpile/module-resolution/monorepo-complicated/packages/mypackage/tsconfig.json
@@ -0,0 +1,7 @@
+{
+    "extends": "../../tsconfig.base.json",
+    "compilerOptions": {
+        "outDir": "../../dist/packages/tstl-module"
+    },
+    "include": ["./src/**/*.ts"]
+}
diff --git a/test/transpile/module-resolution/monorepo-complicated/packages/myprogram/src/main.ts b/test/transpile/module-resolution/monorepo-complicated/packages/myprogram/src/main.ts
@@ -0,0 +1,4 @@
+import { foo } from "mypackage";
+import { bar } from "mypackage/bar";
+
+export { foo, bar };
diff --git a/test/transpile/module-resolution/monorepo-complicated/packages/myprogram/tsconfig.json b/test/transpile/module-resolution/monorepo-complicated/packages/myprogram/tsconfig.json
@@ -0,0 +1,7 @@
+{
+    "extends": "../../tsconfig.base.json",
+    "compilerOptions": {
+        "outDir": "../../dist/packages/tstl-program"
+    },
+    "include": ["./src/**/*.ts"]
+}
diff --git a/test/transpile/module-resolution/monorepo-complicated/tsconfig.base.json b/test/transpile/module-resolution/monorepo-complicated/tsconfig.base.json
@@ -0,0 +1,10 @@
+{
+    "compilerOptions": {
+        "rootDir": ".",
+        "baseUrl": ".",
+        "paths": {
+            "mypackage": ["packages/mypackage/src/index.ts"],
+            "mypackage/*": ["packages/mypackage/src/*"]
+        }
+    }
+}
diff --git a/test/transpile/module-resolution/monorepo-with-paths/mypackage/bar.ts b/test/transpile/module-resolution/monorepo-with-paths/mypackage/bar.ts
@@ -0,0 +1 @@
+export const bar = 271;
diff --git a/test/transpile/module-resolution/monorepo-with-paths/mypackage/index.ts b/test/transpile/module-resolution/monorepo-with-paths/mypackage/index.ts
@@ -0,0 +1 @@
+export const foo = 314;
diff --git a/test/transpile/module-resolution/monorepo-with-paths/mypackage/tsconfig.json b/test/transpile/module-resolution/monorepo-with-paths/mypackage/tsconfig.json
@@ -0,0 +1 @@
+{}
diff --git a/test/transpile/module-resolution/monorepo-with-paths/myprogram/main.ts b/test/transpile/module-resolution/monorepo-with-paths/myprogram/main.ts
@@ -0,0 +1,4 @@
+import { foo } from "mypackage";
+import { bar } from "mypackage/bar";
+
+export { foo, bar };
diff --git a/test/transpile/module-resolution/monorepo-with-paths/myprogram/tsconfig.json b/test/transpile/module-resolution/monorepo-with-paths/myprogram/tsconfig.json
@@ -0,0 +1,9 @@
+{
+    "compilerOptions": {
+        "baseUrl": "..",
+        "outDir": "dist",
+        "paths": {
+            "mypackage": ["mypackage"]
+        }
+    }
+}