add --tsconfig-path option for CLI

readme.md

@@ -71,6 +71,7 @@ Outputs the Node.js compact build of `input.js` into `dist/index.js`.
   --license [file]         Adds a file containing licensing information to the output
   --stats-out [file]       Emit webpack stats as json to the specified output file
   --target [es]            ECMAScript target to use for output (default: es2015)
+  --tsconfig-path [file]   Specify tsconfig.json to use for build (default: resolve tsconfig.json from entrypoint)
                            Learn more: https://webpack.js.org/configuration/target
   -d, --debug              Show debug logs
 ```

src/cli.js

@@ -37,6 +37,7 @@ Options:
   --license [file]         Adds a file containing licensing information to the output
   --stats-out [file]       Emit webpack stats as json to the specified output file
   --target [es]            ECMAScript target to use for output (default: es2015)
+  --tsconfig-path [file]   Specify tsconfig.json to use for build (default: resolve tsconfig.json from entrypoint)
                            Learn more: https://webpack.js.org/configuration/target
   -d, --debug              Show debug logs
 `;
@@ -166,7 +167,8 @@ async function runCmd (argv, stdout, stderr) {
       "-t": "--transpile-only",
       "--license": String,
       "--stats-out": String,
-      "--target": String
+      "--target": String,
+      "--tsconfig-path": String
     }, {
       permissive: false,
       argv
@@ -269,7 +271,8 @@ async function runCmd (argv, stdout, stderr) {
           transpileOnly: args["--transpile-only"],
           license: args["--license"],
           quiet,
-          target: args["--target"]
+          target: args["--target"],
+          tsconfigPath: args["--tsconfig-path"]
         }
       );
 

src/index.js

@@ -1,7 +1,7 @@
 const resolve = require("resolve");
 const fs = require("graceful-fs");
 const crypto = require("crypto");
-const { join, dirname, extname, resolve: pathResolve } = require("path");
+const { basename, dirname, extname, isAbsolute, join, resolve: pathResolve } = require("path");
 const webpack = require("webpack");
 const MemoryFS = require("memory-fs");
 const terser = require("terser");
@@ -54,6 +54,7 @@ function ncc (
     transpileOnly = false,
     license = '',
     target,
+    tsconfigPath = undefined,
     production = true,
     // webpack defaults to `module` and `main`, but that's
     // not really what node.js supports, so we reset it
@@ -109,16 +110,25 @@ function ncc (
     existingAssetNames.push(`${filename}.cache${ext}`);
   }
   const resolvePlugins = [];
+
+  let configFileAbsolutePath;
+  if (tsconfigPath !== undefined) {
+    configFileAbsolutePath = isAbsolute(tsconfigPath)
+    ? tsconfigPath
+    : join(process.cwd(), tsconfigPath);
+  } else {
+    configFileAbsolutePath = walkParentDirs({
+      base: process.cwd(),
+      start: dirname(entry),
+      filename: 'tsconfig.json',
+    });
+  }
+
   // add TsconfigPathsPlugin to support `paths` resolution in tsconfig
   // we need to catch here because the plugin will
   // error if there's no tsconfig in the working directory
   let fullTsconfig = {};
   try {
-    const configFileAbsolutePath = walkParentDirs({
-      base: process.cwd(),
-      start: dirname(entry),
-      filename: 'tsconfig.json',
-    });
     fullTsconfig = loadTsconfig(configFileAbsolutePath) || {
       compilerOptions: {}
     };
@@ -358,6 +368,7 @@ function ncc (
             loader: eval('__dirname + "/loaders/ts-loader.js"'),
             options: {
               transpileOnly,