Added tests, and fixed implementation

 - Still missing refactor, but its getting somewhere.

src/providers/codeAction/swapListItemCodeAction.ts

@@ -14,7 +14,6 @@ import {
 } from "../codeActionProvider";
 import { ICodeActionParams } from "../paramsExtensions";
 
-// Handle adding annotation to let expr declaration
 const refactorName = "swap_listitem";
 const moveListItemUpActionName = "swap_listitem_up";
 const moveListItemDownActionName = "swap_listitem_down";
@@ -25,14 +24,17 @@ CodeActionProvider.registerRefactorAction(refactorName, {
       params.range.start,
     );
 
+    const isListValid = isInValidList(nodeAtPosition);
+    if (!isListValid) return [];
+
     const canMoveNext = getTargetNodes(nodeAtPosition, "next");
     const canMovePrev = getTargetNodes(nodeAtPosition, "previous");
 
     const codeActions: IRefactorCodeAction[] = [];
 
     if (canMovePrev) {
       codeActions.push({
-        title: "Move List item Up",
+        title: "Move list item up",
         kind: CodeActionKind.RefactorRewrite + ".movelistitem.up",
         data: {
           actionName: moveListItemUpActionName,
@@ -45,7 +47,7 @@ CodeActionProvider.registerRefactorAction(refactorName, {
 
     if (canMoveNext) {
       codeActions.push({
-        title: "Move List item Down",
+        title: "Move list item down",
         kind: CodeActionKind.RefactorRewrite + ".movelistitem.down",
         data: {
           actionName: moveListItemDownActionName,
@@ -105,21 +107,41 @@ function getEdits(
 
   const nodeToMove = targets.nodeToMove;
   const nodeToSwapWith = targets.nodeToSwapWith;
-  const nodeToMoveText = nodeToMove.text;
-  const nodeToSwapText = nodeToSwapWith.text;
 
+  const start = findListItemBoundNode(nodeToMove, "previous");
+  const end = findListItemBoundNode(nodeToMove, "next");
+  const start2 = findListItemBoundNode(nodeToSwapWith, "previous");
+  const end2 = findListItemBoundNode(nodeToSwapWith, "next");
+
+  if (!(start && end && start2 && end2)) return [];
+
+  // let nodeToMoveText = "";
+  // nodes1.forEach((x) => (nodeToMoveText += x.text));
+
+  // let nodeToSwapText = "";
+  // nodes2.forEach((x) => (nodeToSwapText += x.text));
+
+  const nodeToMoveText = params.sourceFile.tree.rootNode.text.substring(
+    start.endIndex,
+    end.startIndex,
+  );
+
+  const nodeToSwapText = params.sourceFile.tree.rootNode.text.substring(
+    start2.endIndex,
+    end2.startIndex,
+  );
   const startPosition = PositionUtil.FROM_TS_POSITION(
-    nodeToMove.startPosition,
+    start?.endPosition,
   ).toVSPosition();
   const endPosition = PositionUtil.FROM_TS_POSITION(
-    nodeToMove.endPosition,
+    end.startPosition,
   ).toVSPosition();
 
   const startPosition2 = PositionUtil.FROM_TS_POSITION(
-    nodeToSwapWith.startPosition,
+    start2.endPosition,
   ).toVSPosition();
   const endPosition2 = PositionUtil.FROM_TS_POSITION(
-    nodeToSwapWith.endPosition,
+    end2.startPosition,
   ).toVSPosition();
 
   return [
@@ -143,11 +165,12 @@ function findSiblingSemanticListNode(
 
   let target = iterate(node);
   while (
-    (target?.type == "," ||
-      target?.type == "line_comment" ||
-      target?.type == "[" ||
-      target?.type == "]") &&
-    target != null
+    target != null &&
+    (target.type == "," ||
+      target.type == "line_comment" ||
+      target.type == "block_comment" ||
+      target.type == "[" ||
+      target.type == "]")
   ) {
     if (target.type == "[" || target.type == "]") return null;
     target = iterate(target);
@@ -159,3 +182,35 @@ function findSiblingSemanticListNode(
     return isNext ? inputNode.nextSibling : inputNode.previousSibling;
   }
 }
+
+function isInValidList(node: SyntaxNode): boolean {
+  const list = TreeUtils.findParentOfType("list_expr", node);
+  if (!list) return false;
+
+  const listText = list.text.trim();
+  return listText.startsWith("[") && listText.endsWith("]");
+}
+
+// Find the next list item bound node ('[' or ',' or ']')
+function findListItemBoundNode(
+  node: SyntaxNode,
+  direction: "previous" | "next",
+): SyntaxNode | null {
+  const isNext = direction == "next";
+
+  let target = iterate(node);
+  while (
+    target != null &&
+    target.type != "," &&
+    target.type != "[" &&
+    target.type != "]"
+  ) {
+    target = iterate(target);
+  }
+
+  return target;
+
+  function iterate(inputNode: SyntaxNode): SyntaxNode | null {
+    return isNext ? inputNode.nextSibling : inputNode.previousSibling;
+  }
+}

test/codeActionTests/swapListItemCodeAction.test.ts

@@ -1,7 +1,7 @@
 import { testCodeAction } from "./codeActionTestBase";
 
 describe("swap list item code action", () => {
-  it("should swap item aa with bb", async () => {
+  it("should swap item aa with bb in horizontal list", async () => {
     const source = `
 --@ Test.elm
 module Test exposing (..)
@@ -23,8 +23,242 @@ func =
 
     await testCodeAction(
       source,
-      [{ title: "Move List item Down" }],
+      [{ title: "Move list item down" }],
       expectedSource,
     );
   });
-})
+
+  it("should swap item aa with bb in vertical list", async () => {
+    const source = `
+--@ Test.elm
+module Test exposing (..)
+
+func =
+    [ "aa"
+    --^
+    , "bb"
+    , "cc" 
+    ]
+
+`;
+
+    const expectedSource = `
+--@ Test.elm
+module Test exposing (..)
+
+func =
+    [ "bb"
+    , "aa" 
+    , "cc" 
+    ]
+
+`;
+
+    await testCodeAction(
+      source,
+      [{ title: "Move list item down" }],
+      expectedSource,
+    );
+  });
+  it("should swap item aa with bb in non-standard formatted list", async () => {
+    const source = `
+--@ Test.elm
+module Test exposing (..)
+
+func =
+    [ "a", "bbb",
+    --^
+      "cc"
+    ]
+
+`;
+
+    const expectedSource = `
+--@ Test.elm
+module Test exposing (..)
+
+func =
+    [ "bbb", "a",
+      "cc" 
+    ]
+
+`;
+
+    await testCodeAction(
+      source,
+      [{ title: "Move list item down" }],
+      expectedSource,
+    );
+  });
+
+  it("should swap item aa with bb in vertical list upwards", async () => {
+    const source = `
+--@ Test.elm
+module Test exposing (..)
+
+func =
+    [ -- Comment
+      let 
+        a = 1 
+      in 
+      "aa"
+    , "bb"
+    --^
+    , "cc" 
+    ]
+
+`;
+
+    const expectedSource = `
+--@ Test.elm
+module Test exposing (..)
+
+func =
+    [ "bb"
+    , -- Comment
+      let 
+        a = 1 
+      in 
+      "aa" 
+    , "cc" 
+    ]
+
+`;
+
+    await testCodeAction(
+      source,
+      [{ title: "Move list item up" }],
+      expectedSource,
+    );
+  });
+
+  it("should move comment along with item in vertical list", async () => {
+    const source = `
+--@ Test.elm
+module Test exposing (..)
+
+func =
+    [ -- CommentAA
+      "aa"
+     --^
+    , "bb"
+    ]
+
+`;
+
+    const expectedSource = `
+--@ Test.elm
+module Test exposing (..)
+
+func =
+    [ "bb"
+    , -- CommentAA
+      "aa" 
+    ]
+
+`;
+
+    await testCodeAction(
+      source,
+      [{ title: "Move list item down" }],
+      expectedSource,
+    );
+  });
+
+  it("should move block_comment along with item in vertical list", async () => {
+    const source = `
+--@ Test.elm
+module Test exposing (..)
+
+func =
+    [ {-| CommentAA
+      -}
+      "aa"
+     --^
+    , "bb"
+    ]
+
+`;
+
+    const expectedSource = `
+--@ Test.elm
+module Test exposing (..)
+
+func =
+    [ "bb"
+    , {-| CommentAA
+      -}
+      "aa"
+    ]
+
+`;
+
+    await testCodeAction(
+      source,
+      [{ title: "Move list item down" }],
+      expectedSource,
+    );
+  });
+
+  it("should NOT move comment in preceding item along with item in vertical list", async () => {
+    const source = `
+--@ Test.elm
+module Test exposing (..)
+
+func =
+    [ "aa"
+     --^
+     
+      -- "bb"
+    , "bb"
+    ]
+
+`;
+
+    const expectedSource = `
+--@ Test.elm
+module Test exposing (..)
+
+func =
+    [ "bb"
+    , "aa"
+
+      -- "bb"
+    ]
+
+`;
+
+    await testCodeAction(
+      source,
+      [{ title: "Move list item down" }],
+      expectedSource,
+    );
+  });
+
+  it("should not handle unfinished lists?", async () => {
+    const source = `
+--@ Test.elm
+module Test exposing (..)
+
+func =
+    ([ "aa"
+     --^
+     , "bb"
+    )
+
+`;
+
+    const expectedSource = `
+--@ Test.elm
+module Test exposing (..)
+
+func =
+    ([ "bb"
+     , "aa"    
+    )
+
+`;
+
+    // await testCodeAction(source, [], expectedSource);
+  });
+});