indent using list start position

Author: saschanaz

src/services/formatting/smartIndenter.ts

@@ -130,7 +130,10 @@ namespace ts.formatting {
                 }
 
                 // check if current node is a list item - if yes, take indentation from it
-                let actualIndentation = getActualIndentationForListItem(current, sourceFile, options);
+                // do not consider parent-child line sharing yet:
+                // function foo(a
+                //    | preceding node 'a' does share line with its parent but indentation is expected
+                const actualIndentation = getActualIndentationForListItem(current, sourceFile, options, /*listIndentsChild*/ true);
                 if (actualIndentation !== Value.Unknown) {
                     return actualIndentation;
                 }
@@ -171,22 +174,20 @@ namespace ts.formatting {
                     useActualIndentation = start < ignoreActualIndentationRange.pos || start > ignoreActualIndentationRange.end;
                 }
 
-                if (useActualIndentation) {
-                    // check if current node is a list item - if yes, take indentation from it
-                    const actualIndentation = getActualIndentationForListItem(current, sourceFile, options);
-                    if (actualIndentation !== Value.Unknown) {
-                        return actualIndentation + indentationDelta;
-                    }
-                }
-
                 const containingListOrParentStart = getContainingListOrParentStart(parent, current, sourceFile);
                 const parentAndChildShareLine =
                     containingListOrParentStart.line === currentStart.line ||
                     childStartsOnTheSameLineWithElseInIfStatement(parent, current, currentStart.line, sourceFile);
 
                 if (useActualIndentation) {
+                    // check if current node is a list item - if yes, take indentation from it
+                    let actualIndentation = getActualIndentationForListItem(current, sourceFile, options, !parentAndChildShareLine);
+                    if (actualIndentation !== Value.Unknown) {
+                        return actualIndentation + indentationDelta;
+                    }
+
                     // try to fetch actual indentation for current node from source text
-                    let actualIndentation = getActualIndentationForNode(current, parent, currentStart, parentAndChildShareLine, sourceFile, options);
+                    actualIndentation = getActualIndentationForNode(current, parent, currentStart, parentAndChildShareLine, sourceFile, options);
                     if (actualIndentation !== Value.Unknown) {
                         return actualIndentation + indentationDelta;
                     }
@@ -407,13 +408,21 @@ namespace ts.formatting {
             return findColumnForFirstNonWhitespaceCharacterInLine(sourceFile.getLineAndCharacterOfPosition(list.pos), sourceFile, options);
         }
 
-        function getActualIndentationForListItem(node: Node, sourceFile: SourceFile, options: EditorSettings): number {
+        function getActualIndentationForListItem(node: Node, sourceFile: SourceFile, options: EditorSettings, listIndentsChild: boolean): number {
+            if (node.parent && node.parent.kind === SyntaxKind.VariableDeclarationList) {
+                // VariableDeclarationList has no wrapping tokens
+                return Value.Unknown;
+            }
             const containingList = getContainingList(node, sourceFile);
             if (containingList) {
                 const index = containingList.indexOf(node);
                 if (index !== -1) {
-                    return deriveActualIndentationFromList(containingList, index, sourceFile, options);
+                    const result = deriveActualIndentationFromList(containingList, index, sourceFile, options);
+                    if (result !== Value.Unknown) {
+                        return result;
+                    }
                 }
+                return getActualIndentationForListStartLine(containingList, sourceFile, options) + (listIndentsChild ? options.indentSize : 0);
             }
             return Value.Unknown;
         }