[gjs/esm/static-imports: 40/52] WIP - implement resolveRelativeResourceOrFile in C++

[Evan Welsh <ewlsh src gnome org>]

commit c3e171ad5df7dde5f0cd27fcaf5c296f2e22f229
Author: Philip Chimento <philip chimento gmail com>
Date:   Fri Dec 11 18:28:34 2020 -0800

    WIP - implement resolveRelativeResourceOrFile in C++

 gjs/global.cpp          |  2 ++
 gjs/internal.cpp        | 39 +++++++++++++++++++++++++++++++++++++++
 gjs/internal.h          |  5 +++++
 lib/.eslintrc.yml       |  1 +
 lib/bootstrap/module.js | 25 ++++---------------------
 5 files changed, 51 insertions(+), 21 deletions(-)
---
diff --git a/gjs/global.cpp b/gjs/global.cpp
index 9e2e1b5a..e4b5b766 100644
--- a/gjs/global.cpp
+++ b/gjs/global.cpp
@@ -273,6 +273,8 @@ class GjsInternalGlobal : GjsBaseGlobal {
         JS_FN("getRegistry", gjs_internal_global_get_registry, 1, 0),
         JS_FN("importSync", gjs_internal_global_import_sync, 1, 0),
         JS_FN("parseURI", gjs_internal_parse_uri, 1, 0),
+        JS_FN("resolveRelativeResourceOrFile",
+              gjs_internal_resolve_relative_resource_or_file, 2, 0),
         JS_FN("setModuleLoadHook", gjs_internal_global_set_module_hook, 3, 0),
         JS_FN("setModuleMetaHook", gjs_internal_global_set_module_meta_hook, 2,
               0),
diff --git a/gjs/internal.cpp b/gjs/internal.cpp
index a62d5bfb..ef7082b2 100644
--- a/gjs/internal.cpp
+++ b/gjs/internal.cpp
@@ -473,3 +473,42 @@ bool gjs_internal_parse_uri(JSContext* cx, unsigned argc, JS::Value* vp) {
     args.rval().setObject(*return_obj);
     return true;
 }
+
+bool gjs_internal_resolve_relative_resource_or_file(JSContext* cx,
+                                                    unsigned argc,
+                                                    JS::Value* vp) {
+    JS::CallArgs args = JS::CallArgsFromVp(argc, vp);
+
+    g_assert(args.length() == 2 && "resolveRelativeResourceOrFile(str, str)");
+    g_assert(args[0].isString() && "resolveRelativeResourceOrFile(str, str)");
+    g_assert(args[1].isString() && "resolveRelativeResourceOrFile(str, str)");
+
+    JS::RootedString string_arg(cx, args[0].toString());
+    JS::UniqueChars uri = JS_EncodeStringToUTF8(cx, string_arg);
+    if (!uri)
+        return false;
+    string_arg = args[1].toString();
+    JS::UniqueChars relative_path = JS_EncodeStringToUTF8(cx, string_arg);
+    if (!relative_path)
+        return false;
+
+    GjsAutoUnref<GFile> module_file = g_file_new_for_uri(uri.get());
+    GjsAutoUnref<GFile> module_parent_file = g_file_get_parent(module_file);
+
+    if (module_parent_file) {
+        GjsAutoUnref<GFile> output = g_file_resolve_relative_path(
+            module_parent_file, relative_path.get());
+        GjsAutoChar output_uri = g_file_get_uri(output);
+
+        JS::ConstUTF8CharsZ uri_chars(output_uri, strlen(output_uri));
+        JS::RootedString retval(cx, JS_NewStringCopyUTF8Z(cx, uri_chars));
+        if (!retval)
+            return false;
+
+        args.rval().setString(retval);
+        return true;
+    }
+
+    args.rval().setNull();
+    return true;
+}
diff --git a/gjs/internal.h b/gjs/internal.h
index e6d1a4a3..f347040c 100644
--- a/gjs/internal.h
+++ b/gjs/internal.h
@@ -39,4 +39,9 @@ bool gjs_internal_global_set_module_resolve_hook(JSContext* cx, unsigned argc,
 GJS_JSAPI_RETURN_CONVENTION
 bool gjs_internal_parse_uri(JSContext* cx, unsigned argc, JS::Value* vp);
 
+GJS_JSAPI_RETURN_CONVENTION
+bool gjs_internal_resolve_relative_resource_or_file(JSContext* cx,
+                                                    unsigned argc,
+                                                    JS::Value* vp);
+
 #endif  // GJS_INTERNAL_H_
diff --git a/lib/.eslintrc.yml b/lib/.eslintrc.yml
index 53cfdf5c..fa5bab05 100644
--- a/lib/.eslintrc.yml
+++ b/lib/.eslintrc.yml
@@ -21,6 +21,7 @@ globals:
   compileModule: readonly
   compileInternalModule: readonly
   parseURI: readonly
+  resolveRelativeResourceOrFile: readonly
   setModuleResolveHook: readonly
   setModuleMetaHook: readonly
   setModuleLoadHook: readonly
diff --git a/lib/bootstrap/module.js b/lib/bootstrap/module.js
index 6b5c5f09..7d6287a6 100644
--- a/lib/bootstrap/module.js
+++ b/lib/bootstrap/module.js
@@ -84,26 +84,6 @@ export function loadResourceOrFile(uri) {
     return loadFileSync(output);
 }
 
-/**
- * Resolves a relative path against a URI.
- *
- * @param {string} uri the base URI
- * @param {string} relativePath the relative path to resolve against the base URI
- * @returns {Uri}
- */
-function resolveRelativeResourceOrFile(uri, relativePath) {
-    let module_file = Gio.File.new_for_uri(uri);
-    let module_parent_file = module_file.get_parent();
-
-    if (module_parent_file) {
-        let output = module_parent_file.resolve_relative_path(relativePath);
-
-        return parseURI(output.get_uri());
-    }
-
-    throw new ImportError('File does not have a valid parent!');
-}
-
 /**
  * Handles resolving and loading URIs.
  *
@@ -170,7 +150,10 @@ export class ModuleLoader {
         parseURI(parentURI);
 
         // Handle relative imports from URI-based modules.
-        return resolveRelativeResourceOrFile(parentURI, relativePath);
+        const relativeURI = resolveRelativeResourceOrFile(parentURI, relativePath);
+        if (!relativeURI)
+            throw new ImportError('File does not have a valid parent!');
+        return parseURI(relativeURI);
     }
 
     /**