From e265929f90b6c961466f96679d222c01b1d53bbf Mon Sep 17 00:00:00 2001
From: Daumantas Kavolis <daumantas.kavolis@sensmetry.com>
Date: Wed, 25 Oct 2023 10:19:03 +0300
Subject: [PATCH 1/3] Fix `goto_previous_sibling` with padded first children

---
 cli/src/tests/tree_test.rs | 30 ++++++++++++++++++++++++++++++
 lib/src/tree_cursor.c      |  6 +++++-
 2 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/cli/src/tests/tree_test.rs b/cli/src/tests/tree_test.rs
index c63b588b..161f65e9 100644
--- a/cli/src/tests/tree_test.rs
+++ b/cli/src/tests/tree_test.rs
@@ -376,6 +376,36 @@ fn test_tree_cursor() {
     assert_eq!(copy.node().kind(), "struct_item");
 }
 
+#[test]
+fn test_tree_cursor_previous_sibling() {
+    let mut parser = Parser::new();
+    parser.set_language(get_language("rust")).unwrap();
+
+    let text = "
+    // Hi there
+    // This is fun!
+    // Another one!
+";
+    let tree = parser.parse(text, None).unwrap();
+
+    let mut cursor = tree.walk();
+    assert_eq!(cursor.node().kind(), "source_file");
+
+    assert!(cursor.goto_last_child());
+    assert_eq!(cursor.node().kind(), "line_comment");
+    assert_eq!(cursor.node().utf8_text(text.as_bytes()).unwrap(), "// Another one!");
+
+    assert!(cursor.goto_previous_sibling());
+    assert_eq!(cursor.node().kind(), "line_comment");
+    assert_eq!(cursor.node().utf8_text(text.as_bytes()).unwrap(), "// This is fun!");
+
+    assert!(cursor.goto_previous_sibling());
+    assert_eq!(cursor.node().kind(), "line_comment");
+    assert_eq!(cursor.node().utf8_text(text.as_bytes()).unwrap(), "// Hi there");
+
+    assert!(!cursor.goto_previous_sibling());
+}
+
 #[test]
 fn test_tree_cursor_fields() {
     let mut parser = Parser::new();
diff --git a/lib/src/tree_cursor.c b/lib/src/tree_cursor.c
index 25eca482..f08b9692 100644
--- a/lib/src/tree_cursor.c
+++ b/lib/src/tree_cursor.c
@@ -377,7 +377,11 @@ TreeCursorStep ts_tree_cursor_goto_previous_sibling_internal(TSTreeCursor *_self
   position = parent->position;
   uint32_t child_index = array_back(&self->stack)->child_index;
   const Subtree *children = ts_subtree_children((*(parent->subtree)));
-  for (uint32_t i = 0; i < child_index; ++i) {
+
+  // skip first child padding since its position should match the position of the parent
+  if (child_index > 0)
+    position = length_add(position, ts_subtree_size(children[0]));
+  for (uint32_t i = 1; i < child_index; ++i) {
     position = length_add(position, ts_subtree_total_size(children[i]));
   }
   if (child_index > 0)

From e26e23fd0e6baad6b5285ba1d990142b1f0ff1aa Mon Sep 17 00:00:00 2001
From: Daumantas Kavolis <daumantas.kavolis@sensmetry.com>
Date: Wed, 25 Oct 2023 10:24:35 +0300
Subject: [PATCH 2/3] Fix formatting

---
 cli/src/tests/tree_test.rs | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/cli/src/tests/tree_test.rs b/cli/src/tests/tree_test.rs
index 161f65e9..f3792138 100644
--- a/cli/src/tests/tree_test.rs
+++ b/cli/src/tests/tree_test.rs
@@ -393,15 +393,24 @@ fn test_tree_cursor_previous_sibling() {
 
     assert!(cursor.goto_last_child());
     assert_eq!(cursor.node().kind(), "line_comment");
-    assert_eq!(cursor.node().utf8_text(text.as_bytes()).unwrap(), "// Another one!");
+    assert_eq!(
+        cursor.node().utf8_text(text.as_bytes()).unwrap(),
+        "// Another one!"
+    );
 
     assert!(cursor.goto_previous_sibling());
     assert_eq!(cursor.node().kind(), "line_comment");
-    assert_eq!(cursor.node().utf8_text(text.as_bytes()).unwrap(), "// This is fun!");
+    assert_eq!(
+        cursor.node().utf8_text(text.as_bytes()).unwrap(),
+        "// This is fun!"
+    );
 
     assert!(cursor.goto_previous_sibling());
     assert_eq!(cursor.node().kind(), "line_comment");
-    assert_eq!(cursor.node().utf8_text(text.as_bytes()).unwrap(), "// Hi there");
+    assert_eq!(
+        cursor.node().utf8_text(text.as_bytes()).unwrap(),
+        "// Hi there"
+    );
 
     assert!(!cursor.goto_previous_sibling());
 }

From 143ed959c9a4d591538413b59b935fdba1066a5c Mon Sep 17 00:00:00 2001
From: Daumantas Kavolis <daumantas.kavolis@sensmetry.com>
Date: Wed, 25 Oct 2023 10:47:55 +0300
Subject: [PATCH 3/3] Use single if block

---
 lib/src/tree_cursor.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/lib/src/tree_cursor.c b/lib/src/tree_cursor.c
index f08b9692..63d22c8b 100644
--- a/lib/src/tree_cursor.c
+++ b/lib/src/tree_cursor.c
@@ -378,14 +378,14 @@ TreeCursorStep ts_tree_cursor_goto_previous_sibling_internal(TSTreeCursor *_self
   uint32_t child_index = array_back(&self->stack)->child_index;
   const Subtree *children = ts_subtree_children((*(parent->subtree)));
 
-  // skip first child padding since its position should match the position of the parent
-  if (child_index > 0)
+  if (child_index > 0) {
+    // skip first child padding since its position should match the position of the parent
     position = length_add(position, ts_subtree_size(children[0]));
-  for (uint32_t i = 1; i < child_index; ++i) {
-    position = length_add(position, ts_subtree_total_size(children[i]));
-  }
-  if (child_index > 0)
+    for (uint32_t i = 1; i < child_index; ++i) {
+      position = length_add(position, ts_subtree_total_size(children[i]));
+    }
     position = length_add(position, ts_subtree_padding(children[child_index]));
+  }
 
   array_back(&self->stack)->position = position;