Fix scaffolding snippets to replace typed text instead of inserting (#307)

languageservice/src/complete-action.test.ts

@@ -553,5 +553,31 @@ runs:
       expect(labels).not.toContain("Composite Action");
       expect(labels).not.toContain("Docker Action");
     });
+
+    it("replaces typed text when selecting scaffolding snippet", async () => {
+      // User typed "compo" and then triggered completion
+      const [doc, position] = createActionDocument(`compo|`);
+      const completions = await complete(doc, position, scaffoldingConfig);
+
+      const compositeSnippet = completions.find(c => c.label === "Composite Action");
+      expect(compositeSnippet).toBeDefined();
+
+      // The textEdit should replace "compo", not insert after it
+      const textEdit = compositeSnippet?.textEdit as {range: {start: {character: number}; end: {character: number}}};
+      expect(textEdit.range.start.character).toBe(0); // Start of "compo"
+      expect(textEdit.range.end.character).toBe(5); // End of "compo"
+    });
+
+    it("handles empty file with no typed text", async () => {
+      const [doc, position] = createActionDocument(`|`);
+      const completions = await complete(doc, position, scaffoldingConfig);
+
+      const compositeSnippet = completions.find(c => c.label === "Composite Action");
+      const textEdit = compositeSnippet?.textEdit as {range: {start: {character: number}; end: {character: number}}};
+
+      // Zero-length range is fine when there's nothing to replace
+      expect(textEdit.range.start.character).toBe(0);
+      expect(textEdit.range.end.character).toBe(0);
+    });
   });
 });

languageservice/src/complete-action.ts

@@ -1,7 +1,7 @@
 import {TemplateToken} from "@actions/workflow-parser/templates/tokens/index";
 import {MappingToken} from "@actions/workflow-parser/templates/tokens/mapping-token";
 import {Position} from "vscode-languageserver-textdocument";
-import {CompletionItem, CompletionItemKind, InsertTextFormat, TextEdit} from "vscode-languageserver-types";
+import {CompletionItem, CompletionItemKind, InsertTextFormat, Range, TextEdit} from "vscode-languageserver-types";
 import {Value} from "./value-providers/config.js";
 
 /**
@@ -320,7 +320,8 @@ export function filterActionRunsCompletions(values: Value[], path: TemplateToken
 export function getActionScaffoldingSnippets(
   root: TemplateToken | undefined,
   path: TemplateToken[],
-  position: Position
+  position: Position,
+  replaceRange?: Range
 ): CompletionItem[] {
   // Get the runs mapping from the root, if it exists
   let runsMapping: MappingToken | undefined;
@@ -354,21 +355,24 @@ export function getActionScaffoldingSnippets(
         "Scaffold a Node.js action\n\n[Documentation](https://docs.github.com/en/actions/sharing-automations/creating-actions/creating-a-javascript-action)",
         ACTION_SNIPPET_NODEJS_USING,
         position,
-        "0_nodejs"
+        "0_nodejs",
+        replaceRange
       ),
       createSnippetCompletion(
         "Composite Action",
         "Scaffold a composite action\n\n[Documentation](https://docs.github.com/en/actions/sharing-automations/creating-actions/creating-a-composite-action)",
         ACTION_SNIPPET_COMPOSITE_USING,
         position,
-        "1_composite"
+        "1_composite",
+        replaceRange
       ),
       createSnippetCompletion(
         "Docker Action",
         "Scaffold a Docker action\n\n[Documentation](https://docs.github.com/en/actions/sharing-automations/creating-actions/creating-a-docker-container-action)",
         ACTION_SNIPPET_DOCKER_USING,
         position,
-        "2_docker"
+        "2_docker",
+        replaceRange
       )
     ];
   }
@@ -399,21 +403,24 @@ export function getActionScaffoldingSnippets(
         "Scaffold a Node.js action\n\n[Documentation](https://docs.github.com/en/actions/sharing-automations/creating-actions/creating-a-javascript-action)",
         ACTION_SNIPPET_NODEJS_RUNS,
         position,
-        "1_nodejs"
+        "1_nodejs",
+        replaceRange
       ),
       createSnippetCompletion(
         "Composite Action",
         "Scaffold a composite action\n\n[Documentation](https://docs.github.com/en/actions/sharing-automations/creating-actions/creating-a-composite-action)",
         ACTION_SNIPPET_COMPOSITE_RUNS,
         position,
-        "2_composite"
+        "2_composite",
+        replaceRange
       ),
       createSnippetCompletion(
         "Docker Action",
         "Scaffold a Docker action\n\n[Documentation](https://docs.github.com/en/actions/sharing-automations/creating-actions/creating-a-docker-container-action)",
         ACTION_SNIPPET_DOCKER_RUNS,
         position,
-        "3_docker"
+        "3_docker",
+        replaceRange
       )
     ];
   }
@@ -425,21 +432,24 @@ export function getActionScaffoldingSnippets(
       "Scaffold a complete Node.js action\n\n[Documentation](https://docs.github.com/en/actions/sharing-automations/creating-actions/creating-a-javascript-action)",
       ACTION_SNIPPET_NODEJS_FULL,
       position,
-      "1_nodejs"
+      "1_nodejs",
+      replaceRange
     ),
     createSnippetCompletion(
       "Composite Action",
       "Scaffold a complete composite action\n\n[Documentation](https://docs.github.com/en/actions/sharing-automations/creating-actions/creating-a-composite-action)",
       ACTION_SNIPPET_COMPOSITE_FULL,
       position,
-      "2_composite"
+      "2_composite",
+      replaceRange
     ),
     createSnippetCompletion(
       "Docker Action",
       "Scaffold a complete Docker action\n\n[Documentation](https://docs.github.com/en/actions/sharing-automations/creating-actions/creating-a-docker-container-action)",
       ACTION_SNIPPET_DOCKER_FULL,
       position,
-      "3_docker"
+      "3_docker",
+      replaceRange
     )
   ];
 }
@@ -452,8 +462,12 @@ function createSnippetCompletion(
   description: string,
   snippetText: string,
   position: Position,
-  sortText: string
+  sortText: string,
+  replaceRange?: Range
 ): CompletionItem {
+  // Use replace if we have a range, otherwise insert at position
+  const textEdit = replaceRange ? TextEdit.replace(replaceRange, snippetText) : TextEdit.insert(position, snippetText);
+
   return {
     label,
     kind: CompletionItemKind.Snippet,
@@ -463,6 +477,6 @@ function createSnippetCompletion(
     },
     insertTextFormat: InsertTextFormat.Snippet,
     sortText,
-    textEdit: TextEdit.insert(position, snippetText)
+    textEdit
   };
 }

languageservice/src/complete.ts

@@ -158,12 +158,6 @@ export async function complete(
   const escapeHatches = getEscapeHatchCompletions(token, keyToken, indentString, newPos, schema);
   values.push(...escapeHatches);
 
-  // Get action scaffolding snippets if applicable
-  let actionSnippets: CompletionItem[] = [];
-  if (isAction && config?.featureFlags?.isEnabled("actionScaffoldingSnippets")) {
-    actionSnippets = getActionScaffoldingSnippets(parsedTemplate.value, path, position);
-  }
-
   // Figure out what text to replace when the user picks a completion.
   // For example, if they typed `runs-|` and pick `runs-on`, we need to replace `runs-`.
   let replaceRange: Range | undefined;
@@ -191,6 +185,12 @@ export async function complete(
     }
   }
 
+  // Get action scaffolding snippets if applicable
+  let actionSnippets: CompletionItem[] = [];
+  if (isAction && config?.featureFlags?.isEnabled("actionScaffoldingSnippets")) {
+    actionSnippets = getActionScaffoldingSnippets(parsedTemplate.value, path, position, replaceRange);
+  }
+
   // Convert values to LSP CompletionItems
   const completionItems = values.map(value => {
     const newText = value.insertText || value.label;