From cd4d64b8c70940e350e320130e233adebf3ed56b Mon Sep 17 00:00:00 2001
From: Remy Suen <remy.suen@docker.com>
Date: Tue, 10 Jun 2025 14:08:16 -0400
Subject: [PATCH] Fix offset calculation issue when calculating Compose
 suggestions

Signed-off-by: Remy Suen <remy.suen@docker.com>
---
 CHANGELOG.md                        |  8 ++++++++
 internal/compose/completion.go      |  5 +++++
 internal/compose/completion_test.go | 14 ++++++++++++++
 3 files changed, 27 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 125f4c0..ccbd193 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,14 @@
 
 All notable changes to the Docker Language Server will be documented in this file.
 
+## [Unreleased]
+
+### Fixed
+
+- Compose
+  - textDocument/completion
+    - fix error case triggered by using code completion before the first node ([#314](https://github.com/docker/docker-language-server/issues/314))
+
 ## [0.11.0] - 2025-06-10
 
 ### Added
diff --git a/internal/compose/completion.go b/internal/compose/completion.go
index 8ad9361..0784533 100644
--- a/internal/compose/completion.go
+++ b/internal/compose/completion.go
@@ -206,6 +206,9 @@ func Completion(ctx context.Context, params *protocol.CompletionParams, manager
 	character := int(params.Position.Character) + 1
 	path := constructCompletionNodePath(file, line)
 	if len(path) == 0 {
+		if topLevelNodeOffset != -1 && params.Position.Character != uint32(topLevelNodeOffset) {
+			return nil, nil
+		}
 		return &protocol.CompletionList{Items: createTopLevelItems()}, nil
 	} else if len(path) == 1 {
 		return nil, nil
@@ -570,6 +573,8 @@ func NodeStructure(line int, rootNodes []*ast.MappingValueNode) []*ast.MappingVa
 			candidate = node
 		} else if node.GetToken().Position.Line == line {
 			return []*ast.MappingValueNode{node}
+		} else if candidate == nil {
+			return []*ast.MappingValueNode{}
 		} else {
 			break
 		}
diff --git a/internal/compose/completion_test.go b/internal/compose/completion_test.go
index 95765f4..778ff62 100644
--- a/internal/compose/completion_test.go
+++ b/internal/compose/completion_test.go
@@ -2559,6 +2559,20 @@ services:
 			character: 0,
 			list:      nil,
 		},
+		{
+			name:      "completion is on a line before the first node and after it positionally",
+			content:   " \nservices:",
+			line:      0,
+			character: 1,
+			list:      nil,
+		},
+		{
+			name:      "completion is on a line before the first node and before it positionally",
+			content:   " \n  services:",
+			line:      0,
+			character: 1,
+			list:      nil,
+		},
 	}
 
 	composeFileURI := fmt.Sprintf("file:///%v", strings.TrimPrefix(filepath.ToSlash(filepath.Join(os.TempDir(), "compose.yaml")), "/"))