From dc771fc7adda661fc0aa7f8896dc59fcfdc39051 Mon Sep 17 00:00:00 2001
From: Greg Shuflin <greg@everydayimshuflin.com>
Date: Tue, 23 Apr 2024 02:37:01 -0700
Subject: [PATCH] Working simple tree-sitter grammar

---
 experiments/tree-sitter-test/grammar.js       | 13 +++++++--
 experiments/tree-sitter-test/justfile         |  4 +++
 .../tree-sitter-test/test/corpus/test.txt     | 28 +++++++++++--------
 3 files changed, 31 insertions(+), 14 deletions(-)

diff --git a/experiments/tree-sitter-test/grammar.js b/experiments/tree-sitter-test/grammar.js
index 2de25d1..5fcb29b 100644
--- a/experiments/tree-sitter-test/grammar.js
+++ b/experiments/tree-sitter-test/grammar.js
@@ -9,17 +9,20 @@ module.exports = grammar({
         ),
 
         function_definition: $ => seq(
-            "fn",
+            'fn',
             $.identifier,
             $.parameter_list,
-            optional($._type),
+            field("return_type", optional($._type)),
             $.block,
         ),
         parameter_list: $ => seq("(", /* TODO */ ")"),
 
         block: $ => seq(
             "{",
-            repeat(optional($._statement)),
+            choice(
+                repeat($._statement),
+                "",
+            ),
             "}"
         ),
 
@@ -35,6 +38,10 @@ module.exports = grammar({
         binary: $ => choice(prec.left(2, seq($._expression, "*", $._expression)), prec.left(1, seq($._expression, "+", $._expression))),
 
         _type: $ => "bool",
+        _type: $ => choice(
+            $.primitive_type,
+        ),
+        primitive_type: $ => choice("bool", "int"),
 
         identifier: $ => /[a-z]+/,
     }
diff --git a/experiments/tree-sitter-test/justfile b/experiments/tree-sitter-test/justfile
index 2ca36b2..7904349 100644
--- a/experiments/tree-sitter-test/justfile
+++ b/experiments/tree-sitter-test/justfile
@@ -1,4 +1,8 @@
+_default:
+    just --list
 
 # Test out the grammar
 test-grammar:
+    #!/usr/bin/env bash
+    tree-sitter generate
     tree-sitter test
diff --git a/experiments/tree-sitter-test/test/corpus/test.txt b/experiments/tree-sitter-test/test/corpus/test.txt
index ab26e36..0ef6cff 100644
--- a/experiments/tree-sitter-test/test/corpus/test.txt
+++ b/experiments/tree-sitter-test/test/corpus/test.txt
@@ -4,17 +4,23 @@ Initial test
 fn main() {
 
 }
+----
+(source_file
+    (function_definition
+        (identifier)
+        (parameter_list)
+        (block)
+    )
+)
+
+====
+Another test
+====
+
+fn yolo() bool { }
 
 ----
 
-(source_file)
-
-
-=====
-Another
-====
-
-fn main() bool { }
-
-------
-()
+(source_file
+    (function_definition
+    (identifier) (parameter_list) (primitive_type) (block)))