From 635ff858102ce2e6ccd67738fa02b634af0f698e Mon Sep 17 00:00:00 2001
From: Vasilios Pantazopoulos <vasilios@fullstory.com>
Date: Tue, 16 Aug 2022 17:51:40 -0400
Subject: [PATCH] fix: `ts_project` fail if `root_dir` used deep in source tree

---
 nodejs/private/ts_lib.bzl                                     | 2 +-
 .../typescript/test/ts_project/rootdir_with_value/BUILD.bazel | 1 +
 .../ts_project/rootdir_with_value/subdir/deep/subdir/b.ts     | 1 +
 .../typescript/test/ts_project/rootdir_with_value/verify.js   | 4 ++++
 4 files changed, 7 insertions(+), 1 deletion(-)
 create mode 100644 packages/typescript/test/ts_project/rootdir_with_value/subdir/deep/subdir/b.ts

diff --git a/nodejs/private/ts_lib.bzl b/nodejs/private/ts_lib.bzl
index 329acff22e..32817b19cf 100644
--- a/nodejs/private/ts_lib.bzl
+++ b/nodejs/private/ts_lib.bzl
@@ -169,7 +169,7 @@ def _out_paths(srcs, out_dir, root_dir, allow_js, ext_map):
     outs = []
     for f in srcs:
         if _is_ts_src(f, allow_js):
-            out = _join(out_dir, f[:f.rindex(".")].replace(rootdir_replace_pattern, "") + _replace_ext(f, ext_map))
+            out = _join(out_dir, f[:f.rindex(".")].replace(rootdir_replace_pattern, "", 1) + _replace_ext(f, ext_map))
 
             # Don't declare outputs that collide with inputs
             # for example, a.js -> a.js
diff --git a/packages/typescript/test/ts_project/rootdir_with_value/BUILD.bazel b/packages/typescript/test/ts_project/rootdir_with_value/BUILD.bazel
index 972c7bf1c2..d14db037be 100644
--- a/packages/typescript/test/ts_project/rootdir_with_value/BUILD.bazel
+++ b/packages/typescript/test/ts_project/rootdir_with_value/BUILD.bazel
@@ -5,6 +5,7 @@ load("//packages/typescript:index.bzl", "ts_project")
 SRCS = [
     "subdir/a.ts",
     "subdir/file.json",
+    "subdir/deep/subdir/b.ts",
 ]
 
 ts_project(
diff --git a/packages/typescript/test/ts_project/rootdir_with_value/subdir/deep/subdir/b.ts b/packages/typescript/test/ts_project/rootdir_with_value/subdir/deep/subdir/b.ts
new file mode 100644
index 0000000000..2b5157dcdd
--- /dev/null
+++ b/packages/typescript/test/ts_project/rootdir_with_value/subdir/deep/subdir/b.ts
@@ -0,0 +1 @@
+export const a: string = 'so many folders...';
diff --git a/packages/typescript/test/ts_project/rootdir_with_value/verify.js b/packages/typescript/test/ts_project/rootdir_with_value/verify.js
index 3ac11b00c9..002cf90b60 100644
--- a/packages/typescript/test/ts_project/rootdir_with_value/verify.js
+++ b/packages/typescript/test/ts_project/rootdir_with_value/verify.js
@@ -2,3 +2,7 @@ const assert = require('assert');
 
 const files = process.argv.slice(2);
 assert.ok(files.some(f => f.endsWith('rootdir_with_value/a.js')), 'Missing a.js');
+
+// Test that the only the top-level matching "rootdir" is removed.
+// NOTE: This should never fail directly, as the bug being fixed is a build-time error.
+assert.ok(files.some(f => f.endsWith('rootdir_with_value/deep/subdir/b.js')), 'Missing b.js');