fix(typescript): specify rootDir as absolute path

Also allow non-ts files across src/bin dir, since they are not emitted we don't need the rootdir
calculation to take them into account. This lets the Angular compiler accept .ts sources from
source dir even if the css inputs are generated.

packages/typescript/internal/ts_project.bzl

@@ -76,6 +76,10 @@ def _join(*elements):
         return "/".join(segments)
     return "."
 
+def _is_ts_file(file):
+    ext = file.extension
+    return ext == "js" or ext == "mjs" or ext == "ts" or ext == "tsx" or ext == "json"
+
 def _ts_project_impl(ctx):
     arguments = ctx.actions.args()
     execution_requirements = {}
@@ -89,13 +93,20 @@ def _ts_project_impl(ctx):
         execution_requirements["worker-key-mnemonic"] = "TsProject"
         progress_prefix = "Compiling TypeScript project (worker mode)"
 
-    generated_srcs = False
+    has_generated = None
+    has_source = None
+    root_dir_pre = None
     for src in ctx.files.srcs:
-        if src.is_source:
-            if generated_srcs:
-                fail("srcs cannot be a mix of generated files and source files")
-        else:
-            generated_srcs = True
+        if _is_ts_file(src):
+            if src.is_source:
+                has_source = src.path
+                root_dir_pre = src.root.path
+            else:
+                has_generated = src.path
+                root_dir_pre = ctx.bin_dir.path
+
+    if has_source and has_generated:
+        fail("srcs cannot be a mix of generated files and source files: %s, %s" % (has_generated, has_source))
 
     # Add user specified arguments *before* rule supplied arguments
     arguments.add_all(ctx.attr.args)
@@ -107,7 +118,7 @@ def _ts_project_impl(ctx):
         _join(ctx.bin_dir.path, ctx.label.package, ctx.attr.out_dir),
         "--rootDir",
         _join(
-            ctx.bin_dir.path if generated_srcs else None,
+            root_dir_pre,
             ctx.label.package,
             ctx.attr.root_dir,
         ),