refactor: normalize root/out/declaration dir in macro (#810)

Author: jbedard

ts/defs.bzl

@@ -338,6 +338,12 @@ def ts_project(
             resolve_json_module = resolve_json_module,
         )
 
+    # Normalize common directory path shortcuts such as None vs "." vs "./"
+    out_dir = _clean_dir_arg(out_dir)
+    root_dir = _clean_dir_arg(root_dir)
+    declaration_dir = _clean_dir_arg(declaration_dir)
+
+    # Inferred paths
     typings_out_dir = declaration_dir if declaration_dir else out_dir
     tsbuildinfo_path = ts_build_info_file if ts_build_info_file else name + ".tsbuildinfo"
 
@@ -527,3 +533,8 @@ def _invoke_custom_transpiler(type_str, transpiler, transpile_target_name, srcs,
         )
     else:
         fail("%s attribute should be a rule/macro or a skylib partial. Got %s" % (type_str, type(transpiler)))
+
+def _clean_dir_arg(p):
+    if not p or p == "." or p == "./":
+        return None
+    return p.removeprefix("./")

ts/private/ts_lib.bzl

@@ -236,7 +236,6 @@ def _is_ts_src(src, allow_js, resolve_json_module, include_typings):
 
 def _to_out_path(f, out_dir, root_dir):
     f = f[f.find(":") + 1:]
-    out_dir = out_dir if out_dir != "." else None
 
     if out_dir and f.startswith(out_dir + "/"):
         return f
@@ -249,8 +248,6 @@ def _to_out_path(f, out_dir, root_dir):
 
 def _to_js_out_paths(srcs, out_dir, root_dir, allow_js, resolve_json_module, ext_map, default_ext):
     outs = []
-    out_dir = _remove_leading_dot_slash(out_dir)
-    root_dir = _remove_leading_dot_slash(root_dir)
     for f in srcs:
         if _is_ts_src(f, allow_js, resolve_json_module, False):
             out = _to_out_path(f, out_dir, root_dir)
@@ -349,9 +346,6 @@ def _declare_outputs(ctx, paths):
         for path in paths
     ]
 
-def _remove_leading_dot_slash(string_path):
-    return string_path.removeprefix("./") if string_path else string_path
-
 lib = struct(
     declare_outputs = _declare_outputs,
     join = _join,

ts/private/ts_project.bzl

@@ -167,7 +167,7 @@ See https://github.com/aspect-build/rules_ts/issues/361 for more details.
     # Add user specified arguments *before* rule supplied arguments
     common_args.extend(ctx.attr.args)
 
-    if (ctx.attr.out_dir and ctx.attr.out_dir != ".") or ctx.attr.root_dir:
+    if ctx.attr.out_dir or ctx.attr.root_dir:
         # TODO: add validation that excludes is non-empty in this case, as passing the --outDir or --declarationDir flag
         # to TypeScript causes it to set a default for excludes such that it won't find our sources that were copied-to-bin.
         # See https://github.com/microsoft/TypeScript/issues/59036 and https://github.com/aspect-build/rules_ts/issues/644

ts/test/mock_transpiler.bzl

@@ -53,7 +53,7 @@ def mock(name, srcs, source_map = False, **kwargs):
         srcs = srcs,
         # Calculate pre-declared outputs so they can be referenced as targets.
         # This is an optional transpiler feature aligning with the default tsc transpiler.
-        js_outs = lib.calculate_js_outs(srcs, ".", ".", False, False, False, False),
-        map_outs = lib.calculate_map_outs(srcs, ".", ".", True, False, False, False) if source_map else [],
+        js_outs = lib.calculate_js_outs(srcs, None, None, False, False, False, False),
+        map_outs = lib.calculate_map_outs(srcs, None, None, True, False, False, False) if source_map else [],
         **kwargs
     )