From 0d469abffc833698e2d9249a5ca1306dba5ecc01 Mon Sep 17 00:00:00 2001
From: Tangent Wantwight <tangent128@gmail.com>
Date: Fri, 4 Aug 2023 15:19:36 -0400
Subject: [PATCH] Rearrange grammar to report text-after-closing-brace errors

---
 notcl.js | 49 ++++++++++++++++++++++++++++---------------------
 1 file changed, 28 insertions(+), 21 deletions(-)

diff --git a/notcl.js b/notcl.js
index a7ed44f..38ee7fb 100644
--- a/notcl.js
+++ b/notcl.js
@@ -14,12 +14,13 @@ var Notcl = (() => {
 
   const PreCommand = AtLeast(0, Choose(InterCommandWhitespace, Comment));
 
-  const PreWordWhitespace = Regex(/[^\S\n;]*/y);
+  const PreWordWhitespace = Regex(/[^\S\n;]+/y).expects("whitespace");
 
-  const BasicWord = Regex(/[^\s;]+/y).map(([word]) => ({ text: word }));
+  const BasicWord = Regex(/(?!\{)[^\s;]+/y)
+    .map(([word]) => ({ text: word }))
+    .expects("BASIC_WORD");
 
   // WIP, need to be able to escape braces correctly
-  // WIP, error if anything after closing brace
 
   /** @type {Peg.Pattern<string>} */
   const Brace = Sequence(
@@ -33,29 +34,35 @@ var Notcl = (() => {
     ),
     Regex(/\}/y).expects("}")
   ).map(([_left, fragments, _right]) => fragments.join(""));
-
-  const Word = Sequence(
-    PreWordWhitespace,
-    Choose(
-      Brace.map((text) => ({ text })),
-      BasicWord
-    )
-  ).map(([_padding, word]) => word);
-
-  const CommandTerminator = Sequence(
-    PreWordWhitespace,
-    Choose(/** @type {Peg.Pattern<unknown>} */ (Regex(/[\n;]/y)), End())
+  const Word = Choose(
+    Brace.map((text) => ({ text })),
+    BasicWord
   );
 
+  const CommandTerminator = Choose(
+    /** @type {Peg.Pattern<unknown>} */ (Regex(/[\n;]/y)).expects(
+      "NEWLINE | ;"
+    ),
+    End()
+  );
   /** @type {Peg.Pattern<Notcl.Command>} */
-  const Command = Sequence(PreCommand, AtLeast(0, Word), CommandTerminator).map(
-    ([_padding, words, _end]) => words
-  );
+  const Command = Choose(
+    CommandTerminator.map(() => []),
+    Sequence(
+      Word,
+      AtLeast(
+        0,
+        Sequence(PreWordWhitespace, Word).map(([_padding, word]) => word)
+      ),
+      Choose(Sequence(PreWordWhitespace, Word), CommandTerminator)
+    ).map(([word, moreWords, _end]) => [word].concat(moreWords))
+  ).expects("COMMAND");
 
   /** @type {Peg.Pattern<Notcl.Script>} */
-  const Script = Sequence(AtLeast(0, Command), End()).map(
-    ([commands, _eof]) => commands
-  );
+  const Script = Sequence(
+    AtLeast(0, Sequence(PreCommand, Command)),
+    Choose(End(), Sequence(PreCommand, Command))
+  ).map(([commands, _eof]) => commands.map(([_padding, command]) => command));
 
   const ERROR_CONTEXT = /(?<=([^\n]{0,50}))([^\n]{0,50})/y;