From e179cf25405c5c5d4c329d1782d6e74c8e385669 Mon Sep 17 00:00:00 2001
From: davidot <davidot@serenityos.org>
Date: Wed, 29 Dec 2021 12:15:29 +0100
Subject: [PATCH] LibJS: Don't VERIFY that the token after 'import' is one of
 '.' and '('

Although those are the only valid options parse_primary_expression is
sometimes called when only an expression is valid which means it did not
check match_expression and might fail the now removed VERIFY.
---
 Userland/Libraries/LibJS/Parser.cpp            | 14 +++++++++-----
 .../LibJS/Tests/syntax/dynamic-import-usage.js | 18 ++++++++++++++++++
 2 files changed, 27 insertions(+), 5 deletions(-)
 create mode 100644 Userland/Libraries/LibJS/Tests/syntax/dynamic-import-usage.js

diff --git a/Userland/Libraries/LibJS/Parser.cpp b/Userland/Libraries/LibJS/Parser.cpp
index b785892cab..7132713aae 100644
--- a/Userland/Libraries/LibJS/Parser.cpp
+++ b/Userland/Libraries/LibJS/Parser.cpp
@@ -1425,14 +1425,18 @@ Parser::PrimaryExpressionParseResult Parser::parse_primary_expression()
     }
     case TokenType::Import: {
         auto lookahead_token = next_token();
-        VERIFY(lookahead_token.type() == TokenType::Period || lookahead_token.type() == TokenType::ParenOpen);
         if (lookahead_token.type() == TokenType::ParenOpen)
             return { parse_import_call() };
 
-        if (auto import_meta = try_parse_import_meta_expression()) {
-            if (m_program_type != Program::Type::Module)
-                syntax_error("import.meta is only allowed in modules");
-            return { import_meta.release_nonnull() };
+        if (lookahead_token.type() == TokenType::Period) {
+            if (auto import_meta = try_parse_import_meta_expression()) {
+                if (m_program_type != Program::Type::Module)
+                    syntax_error("import.meta is only allowed in modules");
+                return { import_meta.release_nonnull() };
+            }
+        } else {
+            consume();
+            expected("import.meta or import call");
         }
         break;
     }
diff --git a/Userland/Libraries/LibJS/Tests/syntax/dynamic-import-usage.js b/Userland/Libraries/LibJS/Tests/syntax/dynamic-import-usage.js
new file mode 100644
index 0000000000..b396a7c878
--- /dev/null
+++ b/Userland/Libraries/LibJS/Tests/syntax/dynamic-import-usage.js
@@ -0,0 +1,18 @@
+describe("parsing", () => {
+    test("can parse call import call", () => {
+        expect("import('a')").toEval();
+        expect("import('a', )").toEval();
+        expect("import('a', {options: true})").toEval();
+    });
+
+    test("does not crash on unexpected tokens after import", () => {
+        expect("f = import('a')").toEval();
+
+        expect("f= import").not.toEval();
+        expect("f= import;").not.toEval();
+        expect("f= import?").not.toEval();
+        expect("f= import'").not.toEval();
+        expect("f= import 'a'").not.toEval();
+        expect("f= import['a']").not.toEval();
+    });
+});